Description:FIELD
The present disclosure relates to a hydrothermal liquefaction process for conversion of a feed to an oil and a system thereof.
DEFINITION
As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicates otherwise.
Feed: The term “feed” refers to any microbial biomass and any organic waste such as municipal solid waste (MSW), agri-residue or forest waste, vegetable-fruit waste, effluent treatment plant (ETP) sludge, sewage treatment plant (STP) sludge, pulp and paper industrial waste, municipal organic waste, industrial hydrocarbon waste, lignin biomass, woody biomass, wheat straw, rice straw, and the like.
Hydrothermal liquefaction: The term “hydrothermal liquefaction” refers to hydrolysis and degradation of macromolecules present in a feed by means of water at its near super-critical temperature and pressure condition (or sub-critical conditions) with or without catalyst.
Charring: The term “charring” refers to a process that results in the deposition of salts and char on the equipment due to thermal shock and/or burning to the feed during hydrothermal liquefaction when operated at near super-critical condition of water, for example at 373 °C and 220 bars.
Stage-wise manner: The term “stage-wise manner” refers to the use of two or more operational units such as shear thinning unit, heat exchanger, pressurization unit, depressurization unit, reactors, and the like in series or in parallel. A combination of two types of operational units can also be used in a stage-wise manner.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
Hydrothermal Liquefaction (HTL) in the present context refers to conversion of feed to oil and aqueous effluent with or without catalyst. HTL commonly involves feed-preparation, feed-conditioning, pressurization, heating, reaction, separation and aqueous treatment sections. Majority of the equipment used for HTL including feed processing equipment is commonly known. However, HTL is commonly conducted at near super-critical conditions of water which may result in deposition of salts and char on the equipment due to thermal shock to the feed. The charring leads to a pressure drop within the system and which in turn reduces the run time of the system. Further, there is always a demand to improve the yield and quality of the oil.
Therefore, there is felt a need to develop a hydrothermal liquefaction process for conversion of a feed to oil that overcomes the above-mentioned limitations or provide at least a useful alternative.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows.
It is an object of the present disclosure is to ameliorate one or more problems of the background or to at least provide a useful alternative.
An object of the present disclosure is to provide hydrothermal liquefaction process for conversion of a feed to oil with reduced charring.
Another object of the present disclosure is to provide a hydrothermal liquefaction system for conversion of a feed to oil with reduced charring.
Still another object of the present disclosure is to provide a hydrothermal liquefaction system for conversion of a feed to oil that include an arrangement for feed preparation.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure provides to a hydrothermal liquefaction process for conversion of a feed to oil with reduced charring and a system thereof.
In an aspect the present disclosure provides a hydrothermal liquefaction process for conversion of a feed to oil. The process comprises the following steps:
In a first step, a feed is homogenized in a stage-wise manner in at least one shear thinning unit to obtain a homogenized feed having a predetermined solid content, a predetermined particle size and a predetermined viscosity.
In a second step, the homogenized feed is pressurized in at least one pressurizing unit and heated in at least one heat exchanger in a stage-wise manner to obtain a pressurized and heated slurry having a first predetermined pressure and a first predetermined temperature.
In a third step, the pressurized and heated slurry is reacted in at least one reactor at a first predetermined pressure, at a first predetermined temperature for a predetermined time period to obtain a reaction mixture containing a solid phase, a liquid phase, and a gaseous phase.
In a fourth step, the solid phase is selectively separated in at least one solid separation unit, and the gaseous phase is separated in at least one gas-liquid separation unit from the reaction mixture to obtain a separated solid phase, a separated gaseous phase, and a separated liquid phase consisting of an oil phase and an aqueous phase.
In a fifth step, the separated liquid phase is fed to at least one liquid-liquid separation unit at a second predetermined temperature, at a second predetermined pressure to obtain a separated oil phase and a separated aqueous phase. At least a portion of the separated aqueous phase is recycled to first step for homogenizing the feed. The separated oil phase is the desired oil.
In an embodiment, in the fourth step, the solid phase is separated from the reaction mixture before the reaction mixture is cooled in at least one heat exchanger to a third predetermined temperature (step (a)), is depressurized in at least one depressurization unit to a third predetermined temperature (step (b)), and is degasified in the gas-liquid separation unit at a fourth predetermined pressure and at a fourth predetermined temperature (step (c)), to obtain the separated solid phase, the separated gaseous phase, and the separated liquid phase. The separated liquid phase consists of the oil phase and the aqueous phase.
In another embodiment, in the fourth step, the solid phase is separated from the reaction mixture after the reaction mixture is cooled in at least one heat exchanger to the third predetermined temperature (step (a)), depressurized in at least one depressurization unit to the third predetermined pressure (step (b)), and degasified in a gas-liquid separation unit at the fourth predetermined pressure and at the fourth predetermined temperature (step (c)), to obtain the separated solid phase, the separated gaseous phase, and the separated liquid phase. The separated liquid phase consists of the oil phase and the aqueous phase.
In still another embodiment, in the second step, the homogenized feed is pre-heated in the heat exchanger to a temperature in the range of 30 oC to 200 oC followed by further heating in another heat exchanger to the first predetermined temperature of 250 oC to 373 oC in a stage-wise manner.
In yet another embodiment, in the second step, the homogenized feed is pre-pressurized in a pressuring unit to a pressure in the range of 0.5 bar to 20 bar and pre-heated in a heat exchanger to a temperature in the range of 30 oC to 200 oC, followed by further pressurizing the homogenized feed in another pressurizing unit to the first predetermined pressure in the range of 150 bar to 250 bar and further heating in another heat exchanger to the first predetermined temperature of 250 oC to 373 oC in a stage-wise manner.
In still another embodiment, a heat dissipated during step (a) of cooling in the at least one heat exchanger is transferred to a pressurized slurry of the second step to heat the pressurized slurry.
In yet another embodiment, a pressure recovered during step (b) of depressurization in the at least one depressurization unit is applied for pressurizing the homogenized feed of the second step by using a pressure recovery unit.
In still another embodiment, prior to the fifth step, the separated liquid phase is further cooled in the at least one heat exchanger to a temperature in the range of 30 oC to 90 oC and transferred to the at least one liquid-liquid separation unit to obtain the separated oil phase and the separated aqueous phase.
In yet another embodiment, the feed is prepared from a material selected from at least one of an algal biomass, and an organic waste. The organic waste is at least one selected from the group consisting of a municipal solid waste, an agri-residue, a forest waste, a vegetable-fruit waste, an effluent treatment (ETP) waste, a sewage treatment (STP) waste, a pulp and paper industrial waste, a municipal organic waste, and an industrial hydrocarbon waste.
In still another embodiment, the predetermined solid content of the homogenized feed is in the range of 5 mass% to 35 mass%; the predetermined particle size of the homogenized feed is less than 200 micron; the predetermined viscosity of the homogenized feed is in the range of 5 cP to 95,000 cP; the first predetermined pressure in the second step is in the range of 150 bar to 250 bar; the first predetermined temperature in the second step is in the range of 250 oC to 373 oC; the predetermined time period in the third step is in the range of 5 minutes to 60 minutes; the second predetermined temperature in the at least one liquid-liquid separation unit in the fifth step is in the range of 50 oC to 90 oC; and the second predetermined pressure in the at least one liquid-liquid separation unit of the fifth step is in the range of 1 bar to 5 bar.
In yet another embodiment, the third predetermined temperature in the at least one heat exchanger of step (a) is in the range of 70 oC to 350 oC; the third predetermined pressure in the at least one depressurization unit of step (b) is in the range of 0.5 bar to 20 bar; the fourth predetermined temperature in the gas-liquid separation unit of step (c) is in the range of 70 oC to 220 oC; and the fourth predetermined pressure in the gas-liquid separation unit of step (c) is in the range of 0.5 bar to 20 bar.
In another aspect, the present disclosure provides a hydrothermal liquefaction system for the conversion of a feed to oil. The system comprises at least one shear thinning unit configured to receive the feed from at least one feed storage unit and further configured to homogenize the feed in a stage-wise manner to obtain a homogenized feed; at least one pressurization unit in direct fluid communication with at least one heat exchanger, the at least one pressurization unit is configured to pressurize and heat the homogenized feed to a predetermined temperature and a predetermined pressure in a stage-wise manner; at least one reactor configured to receive a heated and pressurized feed, at the predetermined temperature and the predetermined pressure, from the at least one heat exchanger to obtain a reaction mixture containing a solid phase, a liquid phase and a gaseous phase; at least one solid separation unit and the at least one gas-liquid separation unit are disposed downstream to the at least one reactor and are configured to separate the solid phase, the gaseous phase, and the liquid phase consisting of an oil phase and an aqueous phase; at least one liquid-liquid separation unit is disposed downstream to the at least one gas-liquid separation unit and configured to receive the liquid phase and separate the liquid phase into the oil phase and the aqueous phase; and the at least one effluent storage unit configured to store the aqueous phase received from the at least one liquid-liquid separation unit and further configured to recycle the aqueous phase to the at least one feed storage unit.
In an embodiment, at least one solid separation unit is selectively either disposed upstream to at least one heat exchanger, at least one depressurization unit, and at least one gas-liquid separation unit; or is disposed downstream to at least one heat exchanger, the depressurization unit, and the at least one gas-liquid separation unit.
In another embodiment, the feed storage unit is configured to optionally receive at least a portion of the homogenized feed from the at least one shear thinning unit; and a water tank is configured to supply water to the at least one pressurization unit.
In still another embodiment, the at least one heat exchanger is configured to pre-heat the homogenized feed to a temperature in the range of 30 oC to 200 oC; and the at least one heat exchanger is in direct fluid communication with another at least one heat exchanger, the another at least one heat exchanger is configured to further heat the homogenized feed to the predetermined temperature in the range of 250 oC to 373 oC in a stage-wise manner.
In yet another embodiment, the at least one pressurization unit is in fluid communication with at least one heat exchanger to increase pressure and temperature of the homogenized feed to a pressure of 0.5 bar to 20 bar, and to a temperature of 30 oC to 200 oC in a staged manner; wherein the at least one heat exchanger is in fluid communication with at least one pressurization unit to increase the pressure of the homogenized feed to a pressure in the range of 150 bar to 250 bar, and the at least one pressurization unit is in fluid communication with the at least one heat exchanger to heat the homogenized feed to a temperature in the range of 250 oC to 373 oC.
In still another embodiment, the at least one solid separation unit is disposed upstream to the at least one heat exchanger, the at least one depressurization unit and at least one gas-liquid separation unit; wherein the at least one solid separation unit is in direct fluid communication with the at least one reactor and is configured to receive the reaction mixture at the predetermined temperature in the range of 250 oC to 373 oC at the predetermined pressure in the range of 150 bar to 250 bar to separate the solid phase and a fluid phase containing the gaseous phase and the liquid phase. The at least one heat exchanger is configured to receive the fluid phase containing the liquid phase and the gaseous phase from the at least one solid separation unit and further configured to cool the fluid phase containing said liquid phase and said gaseous phase to a temperature in the range of 70 oC to 350 oC; the depressurization unit is configured to receive the fluid phase from the at least one heat exchanger and is further configured to depressurize the fluid phase to a pressure in the range of 0.5 bar to 20 bar. The gas-liquid separation unit is configured to receive the cooled and depressurized fluid phase from the at least one depressurization unit, and is further configured to separate the fluid phase into the gaseous phase and the liquid phase, wherein the gas-liquid separation unit supplies a stream of separated liquid phase to the liquid-liquid separation unit. The separated solid phase from the at least one solid separation unit is collected in a blow down pot.
In yet another embodiment, the at least one solid separation unit is disposed downstream to the at least one heat exchanger, the at least one depressurization unit, and the at least one gas-liquid separation unit; wherein the at least one heat exchanger is configured to cool the reaction mixture to a temperature in the range of 90 oC to 350 oC; the at least one depressurization unit is configured to receive the cooled reaction mixture from the heat exchanger and further configured to depressurize the cooled reaction mixture to a pressure in the range of 0.5 bar to 20 bar. The gas-liquid separation unit is configured to (i) receive the reaction mixture from the at least one depressurization unit; and (ii) supply a middle stream containing the liquid phase to the liquid-liquid separation unit. The at least one solid separation unit is configured to receive a bottom stream containing the solid phase and a portion of the liquid phase from the gas liquid separation unit.
In the embodiment, the at least one solid separation unit is configured to separate the solid phase and the portion of liquid phase from the bottom stream; and further configured to supply the separated portion of liquid phase to the middle stream; wherein the solid phase from the at least one solid separation unit is collected in another blow down pot.
In still another embodiment, the oil phase from the at least one liquid-liquid separation unit is supplied to at least one oil storage unit; wherein the oil phase is the desired oil.
In yet another embodiment, the system further comprises at least one heat exchanger disposed downstream to the at least one solid separation unit and gas-liquid separation unit, the at least one heat exchanger is configured to cool the middle stream containing the liquid phase and the separated portion of the liquid phase to a temperature in the range of 30 oC to 90 oC.
In still another embodiment, the feed is prepared from a material selected from at least one of an algal biomass, and an organic waste; wherein the at least one organic waste is selected from the group consisting of a municipal solid waste, an agri-residue, a forest waste, a vegetable-fruit waste, an effluent treatment (ETP) waste, a sewage treatment (STP) waste, a pulp and paper industrial waste, a municipal organic waste, and an industrial hydrocarbon waste.
In yet another embodiment, the at least one reactor is selected from a continuous stirred tank reactor (CSTR), a plug flow reactor (PFR), and an ebullated bed reactor (EBR).
In still another embodiment, the at least one pressurization unit is selected from the group consisting of a high pressure pump and a booster pump.
In yet another embodiment, the at least one heat exchanger is selected from the group consisting of a shell and tube heat exchanger, a double pipe heat exchanger, a fired heater, a vessel heater, a tube and tube contact type heat exchanger, a mixing chamber, an air cooler and a water cooler.
In still another embodiment, the at least one depressurization unit is selected from the group consisting of a flash drum, a control valve, a tapered pipe, a constant pressure drop element, and pressure recovery turbine.
In yet another embodiment, the depressurization unit is in fluid communication with a depressurization unit to form a pressure recovery train.
In still another embodiment, the solid separation unit is selected from the group consisting of a candle filter, a hydro-cyclone, a drum separator, a centrifuge, a sintered candle filter, a bag filter, a drum filter and a press filter.
In yet another embodiment, the gas liquid separation unit is selected from the group consisting of a horizontal gas-liquid separator and a vertical gas-liquid separator.
In still another embodiment, the at least two liquid-liquid separation unit is selected from the group consisting of a gravity separator, a centrifuge, a coalescer, and a chemical separation unit.
The present disclosure further provides a hydrothermal liquefaction system for conversion of the feed to the oil to reduce charring, wherein the feed is prepared in an arrangement comprising: a sorting and separation station, a shredding and separation station, a shredding and grinding station, and a homogenizer. The system is configured to convert a plurality of feed to the homogenized feed having the predetermined particle size of less than 200 microns.
In an embodiment, the sorting and separation station is configured to receive and segregate a municipal solid waste. The shredding and separation station is configured to receive the segregated municipal solid waste from the sorting and separation station and an agri-residue or forest waste to further segregate, shred and compress the waste. The shredding and grinding station is configured to receive the segregated and shredded waste from the shredding and separation station and a vegetable-fruit waste to further reduce the size of the waste; and the homogenizer is configured to receive the waste from the shredding and grinding station and a sludge at least one selected from effluent treatment (ETP) and sewage treatment (STP) to homogenize the waste.
In another embodiment, the sorting and separation station comprises at least one unit selected from a magnetic separation unit, an eddy current separation unit and an air density separation unit; the shredding and separation station comprises a unit at least one selected from a magnetic separation unit, an eddy current separation unit, an air density separation, a dry waste shredding unit, and a wet waste shredding unit. The shredding and grinding station comprises at least one unit selected from a dry waste shredding unit, a wet waste shredding unit and a chipping unit.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
The present disclosure will now be described with the help of the accompanying drawing, in which:
Figure 1 illustrates a schematic diagram of a hydrothermal liquefaction (HTL) system (100) in accordance with an embodiment of the present disclosure;
Figure 2 illustrates a schematic diagram of the HTL system (200) in accordance with another embodiment of the present disclosure;
Figure 3 illustrates a schematic diagram of the HTL system (100’) in accordance with still another embodiment of the present disclosure;
Figure 4 illustrates a schematic diagram of the HTL system (200’) in accordance with yet another embodiment of the present disclosure;
Figure 5 illustrate a schematic diagram of the HTL system (200”) in accordance with still another embodiment of the present disclosure; and
Figure 6 illustrates a schematic diagram of the HTL system having feed processing arrangement (300) in accordance with the present disclosure.
LIST OF REFERENCE NUMERALS
Reference no. Reference
100, 200, 100’, 200’, 200” System for conversion of feed
101 Feed storage unit
102, 103 Shear thinning unit
104 Water tank
105, 105’ Pressurization unit
105A, 114, Depressurization unit
106, 107 Heat exchanger
113, 113’ Heat exchanger (cooling unit)
108, 109 Reactor
110, 112, 201, Solid separation unit
111, 202 Blow-down pot
115 Gas-liquid separation unit
116, 119 Liquid-liquid separation unit
117, 120 Effluent water pump
118, 122 Oil mixture pump
121 Effluent storage
123 Oil storage unit
300 Hydrothermal liquefaction system having feed preparation arrangement
302 Sorting and separation station
304 Shredder and separation station
306 Baler
308 Shredder and grinder station
310 Homogenizer
312 Municipality solid waste (MSW)
314 Agri-residue/forest waste
316 Refuse-derived Fuel (RDF)
318 Effluent treatment plant (ETP)/sewage treatment plant (STP) sludge
320 Vegetable waste/food waste
322 Prepared feed

DETAILED DESCRIPTION
The present disclosure relates to a hydrothermal liquefaction process for conversion of a feed to oil with reduced charring and a system thereof.
Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details, are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, elements, components, and/or groups thereof.
As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed elements.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
Hydrothermal Liquefaction (HTL) in the present context refers to conversion of feed to oil and aqueous effluent with or without catalyst. HTL commonly involves feed-preparation, feed-conditioning, pressurization, heating, reaction, separation and aqueous treatment sections. Majority of the equipment used for HTL including feed processing equipment is commonly known. However, HTL is commonly conducted at near super-critical conditions of water which may result in deposition of salts and char on the equipment due to thermal shock to the feed. The charring leads to a pressure drop within the system and which in turn reduces the run time of the system. Further, there is always a demand to improve the oil yield and quality.
Referring to figures 1-5, figure 1 and figure 2 represent separate embodiments for the hydrothermal liquefaction systems (100, 200) for the conversion of a feed to oil in accordance with the present disclosure. Figure 3 represents an embodiment for system 100. Figure 4 represents an embodiment for system 200. Figure 5 represents another embodiment for system 200.
In an aspect, the present disclosure provides a hydrothermal liquefaction process for conversion of a feed to oil. The process comprises the following steps, which are described below with the help of the Figures 1-5.
In a first step, a feed is homogenized in a stage-wise manner in at least one shear thinning unit (102, 103) to obtain a homogenized feed having a predetermined solid content, a predetermined particle size and a predetermined viscosity.
In accordance with the embodiments of the present disclosure, the predetermined solid content of the homogenized feed is in the range of 5 mass% to 35 mass%. In an exemplary embodiment, the predetermined solid content of the homogenized feed is 10 mass%. In another exemplary embodiment, the predetermined solid content of the homogenized feed is 20 mass%. In still another exemplary embodiment, the predetermined solid content of the homogenized feed is 15 mass%.
In accordance with the embodiments of the present disclosure, the predetermined particle size of the homogenized feed of less than 200 microns. In an embodiment, the predetermined particle size of the homogenized feed is <100 microns. In another embodiment, the particle size of the homogenized feed is less than 50 microns.
In accordance with the embodiments of the present disclosure, the predetermined viscosity of the homogenized feed is in the range of 5 cP to 95,000 cP. In an exemplary embodiment, the predetermined viscosity is 10 cP, when the solid content is 10 mass% and homogenized at a shear thinning rate of 1500 s-1. In another exemplary embodiment, the predetermined viscosity is 20 cP, when the solid content is 15% and homogenized at a shear rate of 1500 s-1. In still another exemplary embodiment, the predetermined viscosity is 85,000 cP, when the solid content is 24% and homogenized at a shear rate of 10 s-1.
The system of the present disclosure works at higher viscosities as long as the feed is flowable. The viscosity value varies as per the type of the feed, so a maximum viscosity value of the homogenized feed cannot be significant.
In accordance with the embodiments of the present disclosure, the shear rate in the shear thinning unit (102, 103) is in the range of 0.05 s-1 to 1600 s-1. In an exemplary embodiment, the shear rate in the shear thinning unit (102, 103) is 0.07 s-1. In another exemplary embodiment, the shear rate in the shear thinning unit (102, 103) is 100 s-1. In still another exemplary embodiment, the shear rate in the shear thinning unit (102, 103) is 1000 s-1. In yet another exemplary embodiment, the shear rate in the shear thinning unit (102, 103) is 1500 s-1.
In a second step, the homogenized feed is pressurized in at least one pressurizing unit (105, 105’) followed by heating in at least one heat exchanger (106, 107) in a stage-wise manner to obtain a pressurized and heated slurry having a first predetermined pressure and a first predetermined temperature.
In accordance with the embodiments of the present disclosure, the first predetermined pressure is in the range of 150 bar to 250 bar. In the exemplary embodiments, the first predetermined pressure is 190 bar.
In accordance with the embodiments of the present disclosure, the first predetermined temperature is in the range of 250 oC to 373 oC. In an exemplary embodiment, the first predetermined temperature is 315 oC. In another exemplary embodiment, the first predetermined temperature is 330 oC. In still another exemplary embodiment, the first predetermined temperature is 340 oC. In yet another exemplary embodiment, the first predetermined temperature is 350 oC. In still another exemplary embodiment, the first predetermined temperature is 325 oC.
In an embodiment, in the second step as illustrated in the Figures 1 and 2, the homogenized feed is pre-heated in the heat exchanger (106) to a temperature in the range of 30 oC to 200 oC followed by further heating in the heat exchanger (107) to the first predetermined temperature in the range of 250 oC to 373 oC in a stage-wise manner.
The pre-heating temperature of the homogenized feed is in the range of 30 oC to 200 oC depends on the type and moisture content of the feed. When the moisture content in the homogenized feed is low, the feed tends to have high viscosity. A higher temperature is required to reduce the viscosity of the homogenized feed to facilitate free flow of the feed. The feed having low moisture content such as food waste, municipality solid waste (MSW), and the like requires extensive feed preparation and the feed temperature entering the heat exchanger (106) is on the higher side, which are further pre-heated up to 200 oC in the heat exchanger (106). In some cases, the step of homogenization itself increases the feed temperature. In case of 10% algae slurry, wherein no extensive feed preparation is required, the feed enters the heat exchanger (106) at ~30 oC and is heated up to 200 oC.
In another embodiment, in the second step as illustrated in Figures 3-5, the homogenized feed is pre-pressurized in the pressurizing unit (105) to a pressure in the range of 0.5 bar to 20 bar and pre-heated in the heat exchanger (106) to a temperature in the range of 30 oC to 200 oC, followed by further pressurizing the homogenized feed in the pressurizing unit (105’) to the first predetermined pressure in the range of 150 bar to 250 bar and further heating in the heat exchanger (107) to the first predetermined temperature of 250 oC to 373 oC in a stage-wise manner.
In a third step, the pressurized and heated slurry is reacted in at least one reactor (108, 109) at the first predetermined pressure, at the first predetermined temperature for a predetermined time period to obtain a reaction mixture containing a solid phase, a liquid phase, and a gaseous phase.
In accordance with the present disclosure, the predetermined time period in the third step is in the range of 5 minutes to 60 minutes. In an exemplary embodiment, the predetermined time period is 30 minutes. In another exemplary embodiment, the predetermined time period is 20 minutes. In still another exemplary embodiment, the predetermined time period is 40 minutes.
In a fourth step, the solid phase is selectively separated in at least one solid separation unit (110, 112, 201), and the gaseous phase is separated in at least one gas-liquid separation unit (115) from the reaction mixture to obtain a separated solid phase, a separated gaseous phase, and a separated liquid phase. The separated liquid phase consists of an oil phase and an aqueous phase.
In an embodiment, in the fourth step as illustrated in Figures 1 and 3, the solid phase is separated in the solid separation unit (110, 112) from the reaction mixture before (a fluid phase of) the reaction mixture is cooled in at least one heat exchanger (106, 113, 113’) to a third predetermined temperature (step (a)), depressurized in at least one depressurization unit (114, 105A) to a third predetermined pressure (step (b)), and degasified in the gas-liquid separation unit (115) at a fourth predetermined pressure and at a fourth predetermined temperature (step (c)), to obtain the separated solid phase, the separated gaseous phase, and the separated liquid phase. The separated liquid phase consists of the oil phase and the aqueous phase.
In another embodiment, in the fourth step as illustrated in Figures 2, 4 and 5, the solid phase is separated in the solid separation unit (201) from the reaction mixture after the reaction mixture is cooled in at least one heat exchanger (106, 113) to the third predetermined temperature (step (a)), is depressurized in at least one depressurization unit (114, 105A) to the third predetermined pressure (step (b)), and is degasified in a gas-liquid separation unit (115) at the fourth predetermined pressure and at the fourth predetermined temperature (step (c)), to obtain the separated solid phase, the separated gaseous phase, and the separated liquid phase. The separated liquid phase consists of the oil phase and the aqueous phase.
In accordance with the embodiments of the present disclosure, the third predetermined temperature in the at least one heat exchanger (106, 113) of step (a) is in the range of 70 oC to 350 oC. In an exemplary embodiment, the third predetermined temperature is 90 oC. In another exemplary embodiment, the third predetermined temperature is 210 oC.
In accordance with the embodiments of the present disclosure, the third predetermined pressure in the at least one depressurization unit (114, 105A) of step (b) is in the range of 0.5 bar to 20 bar. In the exemplary embodiment, the third predetermined pressure is 18 bar, when the solid separation is done in solid separation unit (201). In another exemplary embodiment, the third predetermined pressure is 1 bar, when the solid separation is done is solid separation units (110, 112).
In accordance with the embodiments of the present disclosure, the fourth predetermined temperature in the gas-liquid separation unit (115) of step (c) is in the range of 70 oC to 220 oC. In an exemplary embodiment, the fourth predetermined temperature in the gas-liquid separation unit (115) of step (c) is 80 oC. In another exemplary embodiment, the fourth predetermined temperature in the gas-liquid separation unit (115) is 200 oC. In an embodiment, the fourth predetermined temperature in the gas-liquid separation unit (115) is 120 oC.
In accordance with the embodiments of the present disclosure, the fourth predetermined pressure in the gas-liquid separation unit (115) of step (c) is in the range of 0.5 bar to 20 bar. In an exemplary embodiment, the fourth predetermined pressure in the gas-liquid separation unit (115) of step (c) is 1 bar. In another exemplary embodiment, the fourth predetermined pressure in the gas-liquid separation unit (115) is 18 bar. In an embodiment, the fourth predetermined pressure in the gas-liquid separation unit (115) is 1.5 bar.
In a fifth step, the separated liquid phase is fed to at least one liquid-liquid separation unit (116, 119) at a second predetermined temperature, at a second predetermined pressure to obtain a separated oil phase and a separated aqueous phase.
At least a portion of the separated aqueous phase is recycled to the first step for homogenizing the feed, wherein the separated oil phase is the desired oil.
In accordance with the embodiments of the present disclosure, the second predetermined temperature in the at least one liquid-liquid separation unit (116, 119) in the fifth step is in the range of 50 oC to 90 oC. In an exemplary embodiment, the second predetermined temperature in the at least one liquid-liquid separation unit (116, 119) in the fifth step is 80 oC
In accordance with the embodiments of the present disclosure, the second predetermined pressure in the at least one liquid-liquid separation unit (116, 119) of the fifth step is in the range of 1 bar to 5 bar. In accordance with an embodiment, the second predetermined pressure in the at least one liquid-liquid separation unit (116, 119) of the fifth step is 2 bar.
In accordance with the embodiments of the present disclosure, a heat dissipated during step (a) of cooling in the at least one heat exchanger (106, 113) is transferred to a pressurized slurry of the second step to heat the pressurized slurry.
In accordance with the embodiments of the present disclosure, a pressure recovered during step (b) of depressurization in the at least one depressurization unit (114, 105A) is applied for pressurizing the homogenized feed of the second step by using a pressure recovery unit.
In accordance the embodiments of the present disclosure, prior to the fifth step as illustrated in Figure 5, the separated liquid phase is further cooled in the at least one heat exchanger (113’) to a temperature in the range of 30 oC to 90 oC and transferred to the at least one liquid-liquid separation unit (116, 119) to obtain the separated oil phase and the separated aqueous phase. In an exemplary embodiment, the separated liquid phase is further cooled in the at least one heat exchanger (113’) to a temperature of 40 oC and transferred to the at least one liquid-liquid separation unit (116, 119) to obtain the separated oil phase and the separated aqueous phase.
In accordance the embodiments of the present disclosure, the feed is prepared from a material selected from at least one of an algal biomass and an organic waste. The organic waste is at least one selected from the group consisting of a municipal solid waste, an agri-residue, a forest waste, a vegetable-fruit waste, an effluent treatment (ETP) waste, a sewage treatment (STP) waste, a pulp and paper industrial waste, a municipal organic waste, and an industrial hydrocarbon waste.
In another aspect, the present disclosure provides a hydrothermal liquefaction system (100, 200, 100’, 200’ and 200”) for the conversion of a feed to an oil. The hydrothermal liquefaction system (100, 200, 100’, 200’ and 200”) for the conversion of a feed to oil is described in detail using the Figures 1-6.
At least one shear thinning unit (102, 103) is configured to receive a feed from at least one feed storage unit (101) and further configured to homogenize the feed in a stage-wise manner to obtain a homogenized feed.
In accordance the embodiments of the present disclosure, the feed is prepared from a material selected from at least one of an algal biomass and an organic waste. The organic waste is at least one selected from the group consisting of a municipal solid waste, an agri-residue, a forest waste, a vegetable-fruit waste, an effluent treatment (ETP) waste, a sewage treatment (STP) waste, a pulp and paper industrial waste, a municipal organic waste, and an industrial hydrocarbon waste.
In an embodiment, the feed storage unit (101) is configured to receive at least a portion of the homogenized feed from the at least one shear thinning unit (102, 103), and a water tank (104) is configured to supply water to the at least one pressurization unit (105).
The shear thinning unit (102, 103) has at least one shear thinning pump that help reduce viscosity and homogenize the feed by circulating it back to the feed storage unit (101), which makes the feed easily pumpable.
At least one pressurization unit (105, 105’) is in direct fluid communication with at least one heat exchanger (106, 107). The at least one pressurization unit (105, 105’) and at least one heat exchanger (106, 107) are configured to pressurize and heat the homogenized feed to a predetermined temperature and a predetermined pressure in a stage-wise manner.
In accordance with the embodiments of the present disclosure, the at least one pressurization unit (105, 105’) is selected from the group consisting of a high pressure pump and a booster pump, which is either centrifugal or positive displacement type of pumps. In an embodiment, the pressurization unit (105) is a high pressure pump.
In an embodiment, as illustrated in Figures 1 and 2, the at least one heat exchanger (106) is configured to pre-heat the homogenized feed to a temperature in the range of 30 oC to 200 oC. The at least one heat exchanger (107) is in direct fluid communication with the at least one heat exchanger (107), the at least one heat exchanger (107) is configured to further heat the homogenized feed to the predetermined temperature in the range of 250 oC to 373 oC in a stage-wise manner.
The at least two heat exchanger (106, 107) are staged to minimize the salt deposition and reduce the charring effect of the feed due to sudden rise in the temperature of the feed. The staged heating helps in reducing the thermal shock faced by feed slurry in the heat exchanger, thus reducing the charring inside the heat exchangers.
In another embodiment, as illustrated in Figures 3-5, the at least one pressurization unit (105) is in fluid communication with at least one heat exchanger (106) to increase pressure and temperature of the homogenized feed to a pressure of 0.5 bar to 20 bar, and to a temperature of 30 oC to 200 oC in a staged manner; wherein the at least one heat exchanger (106) is in fluid communication with at least one pressurization unit (105’) to increase the pressure of the homogenized feed to a pressure in the range of 150 bar to 250 bar, and the at least one pressurization unit (105’) is in fluid communication with the at least one heat exchanger (107) to heat the homogenized feed to a temperature of 250 oC to 373 oC.
In accordance with the embodiments of the present disclosure, the at least one heat exchanger (106, 107, 113, 113’) that are utilized for this purpose including and not limited to a shell and tube heat exchanger, a double pipe heat exchanger, a fired heater, a vessel heater, a tube and tube contact type heat exchanger, a mixing chamber, an air cooler and a water cooler. The mixing chamber allows mixing of the feed with high temperature water/effluent stream and the like.
In accordance with the embodiments of the present disclosure, the heat exchanger (106) can act as a heater for the feed and a cooler for the product stream.
In accordance with the present disclosure, the heat exchangers (106, 107) provides heat to the homogenized feed which can be done by using one of the steam, thermal fluid, fired heater, molten salt, HTL oil, Electrical heaters and the like. Heating is done with the help of single heat exchanger or by putting a series of heat exchangers which may or may not vary in the make/type of heat exchanger.
At least one reactor (108, 109) configured to receive a heated and pressurized feed, at the predetermined temperature and the predetermined pressure, from the at least one heat exchanger (107) to obtain a reaction mixture containing a solid phase, a liquid phase and a gaseous phase.
In accordance with the embodiments of the present disclosure, the at least one reactor (108, 109) is selected from a continuous stirred tank reactor (CSTR), a plug flow reactor (PFR), and an ebullated bed reactor (EBR). In an exemplary embodiment, the reactor is a CSTR reactor. In another exemplary embodiment, the reactor is a combination of CSTR and PFR.
Different configuration of different type of reactor including CSTR and PFR helps to optimize residence time of the reaction leading to best yield/conversion of biomass to oil. Also, selection between either one of CSTR or PFR depends on the economic feasibility i.e. whichever has lower cost for the particular scale of operation.
The reactors are utilized either as stand-alone reactor or in series or in parallel to each other. At elevated pressure and temperatures, the viscosity and dielectric constant of water decreases, whereas the ionic product increases significantly. In addition to bio-crude and bio-char, other products of HTL are CO2 rich non-condensable gases with varying contents of H2, CH4 and CO depending on type of biomass and reaction conditions, and an aqueous phase with soluble organics, mostly in the form of alcohols, acids and phenols are generated. Further, the product characteristics and yields in HTL largely depends on operating parameters such as biomass type, biomass-to-water ratio, temperature, pressure, residence time in the reactor, and the presence or absence of catalyst.
At least one solid separation unit (110, 112, 201) and the at least one gas-liquid separation unit (115) is disposed downstream to the at least one reactor (108, 109) and are configured to separate the solid phase, the gaseous phase, and the liquid phase. The liquid phase consists of an oil phase and an aqueous phase. The at least one solid separation unit (110, 112, 201) is selectively either disposed upstream to at least one heat exchanger (106, 113, 113’), at least one depressurization unit (114, 105A), and at least one gas-liquid separation unit (115); or is disposed downstream to the at least one heat exchanger (106, 113), the depressurization unit (114, 105A), and the at least one gas-liquid separation unit (115).
In an embodiment, as illustrated in Figures 1 and 3, at least one solid separation unit (110, 112) is disposed upstream to the at least one heat exchanger (106, 113, 113’), the at least one depressurization unit (114, 105A), and the at least one gas-liquid separation unit (115). The at least one solid separation unit (110, 112) is in direct fluid communication with the at least one reactor (108, 109) and is configured to receive the reaction mixture at the predetermined temperature in the range of 250 oC to 373 oC at the predetermined pressure in the range of 150 bar to 250 bar to separate the solid phase and a fluid phase containing the gaseous phase and the liquid phase. The at least one heat exchanger (106, 113) is configured to receive the fluid phase containing the liquid phase and the gaseous phase from the at least one solid separation unit (110, 112) and further configured to cool the fluid phase containing the liquid phase and the gaseous phase to a temperature in the range of 70 oC to 350 oC. The depressurization unit (114, 105A) is configured to receive the fluid phase from the at least one heat exchanger (113) and is further configured to depressurize the fluid phase to a pressure in the range of 0.5 bar to 20 bar. The gas-liquid separation unit (115) is configured to receive the cooled and depressurized fluid phase from the at least one depressurization unit (104), and is further configured to separate the fluid phase into the gaseous phase and the liquid phase, wherein the gas-liquid separation unit (115) supplies a stream of separated liquid phase to the liquid-liquid separation unit (116). The separated solid phase from the at least one solid separation unit (110, 112) is collected in a blow down pot (111).
In another embodiment, as illustrated in Figure 2, at least one solid separation unit (201) is disposed downstream to at least one heat exchanger (106, 113), the at least one depressurization unit (114, 105A), and the at least one gas-liquid separation unit (115). The at least one heat exchanger (106, 113) is configured to cool the reaction mixture to a temperature in the range of 90 oC to 350 oC; and the at least one depressurization unit (114) is configured to receive the cool reaction mixture from the heat exchanger (113) and further configured to depressurize the cool reaction mixture to a pressure in the range of 0.5 bar to 20 bar. The gas-liquid separation unit (115) is configured to: (i) receive the reaction mixture from the at least one depressurization unit (114), (ii) separate the reaction mixture into a top stream containing the gaseous phase, a middle stream containing the liquid phase, and a bottom stream containing the solid phase and a portion of the liquid phase, and (iii) supply the middle stream containing the liquid phase to the liquid-liquid separation unit (116). The at least one solid separation unit (201) is configured to receive the bottom stream containing solid phase and the portion of the liquid phase from the gas-liquid separation unit (115). The at least one solid separation unit (201) is configured to separate the solid phase and the portion of liquid phase from the bottom stream, and further configured to supply the separated portion of liquid phase to the liquid-liquid separation unit (116). The solid phase from the at least one solid separation unit (201) is collected in a blow down pot (202).
The system (200, 200’ and 200”) wherein the solid separation unit (201) is disposed downstream to the heat exchanger (106), the heat exchanger (113) and the depressurization unit (114) and is operated at lower pressure which in turn reduce the operating cost of the system. These systems are employed in large scale plant where depressurization unit (114) can handle solid particles because of larger line sizes.
At least one liquid-liquid separation unit (116, 119) is disposed downstream to the at least one gas-liquid separation unit (115) and is configured to receive the liquid phase and separate the liquid phase into the oil phase and the aqueous phase.
As illustrated in Figures 1-5, the liquid-liquid separation units (116) separate the oil phase and the aqueous phase based on the sedimentary property/specific gravity of the fluids. Residual water from the separated oil is removed based on the electrochemical precipitation principle or equivalent principle by using another liquid-liquid separation unit (119).
As illustrated in Figures 1-5, at least one effluent storage unit (121) is configured to store the aqueous phase received from the at least one liquid-liquid separation unit (116, 119) and further configured to recycle the aqueous phase to the at least one feed storage unit (101). The oil phase from the at least one liquid-liquid separation unit (116, 119) is supplied to at least one oil storage unit (123). The oil phase is the desired oil.
Viscosity reduction is generally obtained through shear thinning system. Recycling of aqueous phase effluent or adding of additional water also impacts the overall viscosity as well as the solid concentration, which enhances the flowability or pumpability of the feed for transportation in pipes.
The aqueous phase effluent having total organic carbon (TOC) in range of 5000 ppm to 50000 ppm and is rich in hydrocarbon content and its recirculation/recycle results into increase in oil yield up to 30%.
Recycling of the aqueous phase effluent reduces the impact of char and/or salt deposition in the system. Recycling of the aqueous phase effluent reduces the charring of the feed biomass and increase oil quality. The aqueous phase effluent is stored in the effluent storage unit for further treatment to recover the nutrients. The effluent with or without treatment is recycled to feed storage unit (101) to enhance oil yield, to reduce fouling and charring of the feed, to manage biomass or waste slurry required solid loading. Reduced settling/charring of the biomass slurry results into better performance of the system in accordance with the present disclosure. The charring resistivity of the system of the present disclosure is attributed to small amount of hydrocarbons present in the recycled aqueous phase effluent that forms a thin lubricating layer across the heat exchangers. Recycling of effluent develop a protective layer on the system surface thus reducing the char deposition tendency.
The aqueous effluent contains soluble polar organics such as carboxylic acids, alcohols, ketones and the like which helps solubilizing biomass components during recycling. Often these small molecules catalyze the hydrolysis of solid biopolymers such as carbohydrates, proteins and the like that are present in the feed and help in further dehydration reactions. This catalytic effect reduces the charring and coking tendencies due to increased reaction kinetics, which ultimately results in an increase in the product yield.
In an embodiment, the system, as shown in Figure 5, further comprises at least one heat exchanger (113’) disposed downstream to the at least one solid separation unit (201) and gas-liquid separation unit (115) configured to cool the middle stream containing the liquid phase and the separated portion of liquid phase to a temperature in the range of 30 oC to 90 oC. In an exemplary embodiment, the middle stream containing the liquid phase and the portion of liquid phase is cooled to a temperature of 40 oC in the heat exchanger (113’).
In accordance with the embodiments of the present disclosure, the at least one depressurization unit (114, 105A) is selected from the group consisting of a flash drum, a control valve, a tapered pipe, a constant pressure drop element, and a pressure recovery turbine. In an embodiment, as illustrated in Figures 3-5, the depressurization unit (105) is in fluid communication with a depressurization unit (105A) to form a pressure recovery train.
The depressurization unit (105A) of a pressure recovery train helps in recovering about 60 to 80% of a total pressure energy, thereby positively impacting the economics of the project. The pressure recovery train employs series of equipment including rotatory equipment through which a pressurized stream is passed. The pressurized stream gets de-pressurized while transferring the power to the rotary equipment which in turns supply the generated power back to the pressurization unit (105). This reduces the energy expenditure of the plant.
In accordance with the embodiments of the present disclosure, the solid separation unit (110, 112, 201) is selected from the group consisting of a candle filter, a hydro-cyclone, a drum separator, a centrifuge, a sintered candle filter, a bag filter, a drum filter and a press filter.
In accordance with the embodiments of the present disclosure, the gas liquid separation unit (115) is selected from the group consisting of a horizontal gas-liquid separator and a vertical gas-liquid separator.
In accordance with the embodiments of the present disclosure, the at least two liquid-liquid separation unit (116, 119) is selected from the group consisting of a gravity separator, a centrifuge, a coalescer, and a chemical separation unit.
Though the desired total residence time (predetermined time period) required for the reaction is 10 minutes to 60 minutes at the predetermined temperature and the predetermined pressure. Individual reactor by-pass arrangements or combination of above mentioned reactors in series/parallel provides residence time flexibility for optimizing yields. The reactor is externally heated with heating tapes/steam tracing/ electrical tracing and insulated to compensate heat loss to maintain the feed at a temperature in the range of 250 oC to 373 oC.
Solid phase separation after cooling and depressurization reduces pressure fluctuations and disturbances during the continuous operations. It reduces the total solid load on solid separation equipment and also provides ease of solid removal without disturbing the operating condition. It involves two or more solid separators that are candle filters, hydro-cyclone, drum separator and the like. In case of candle filter, the solid phase from each candle housing is back flushed in a particular time interval such that only one out of many candle filter housing is offline at a time. The back flushed solid phase goes to an additional candle filter (solid filter) where the solid is collected. Once the solid filter receives solid from number of process candle filters, then blow down is taken thus the operating condition of the system remains un-affected. The solid phase is separated by using candle filters in precipitation vessel by taking periodic blowdowns.
The multiple parallel filters are used for solid separation. Each filter is washed periodically by implementing a backwash sequence using pressurized filter outlet stream / water. The washed stream is to be collected in a blowdown pot. This system ensures that entire process is not disturbed during cleaning cycle of filters.
Solid phase separation after cooling and depressurization (temperature < 250 oC) in solid separation unit (201) helps in elimination of severe condition as faced during hot conditions and also provides more options in terms of type of equipment that are utilized such as sintered candle filter, centrifuges, bag filter, drum filter, hydro-cyclone, press filter and the like. For cold separation, reactor outlet is cooled prior to sending it to the solid separation unit which is done by series of recovery exchanger or with the help of air cooler or water cooler as per the utility available at site.
The multi-staged liquid-liquid separation helps in better separation of oil at both high and low pressure conditions. This is achieved with one or more gravity separation equipment or by using one or more coalesce or using them in combination.
Aqueous oil separation is done at both high pressure and low pressure depending on feed and product characteristics.
The solids are formed due to precipitation at sub-critical condition of water. Therefore, velocity of the solids above settling velocity needs to be maintained in the reactor.
The heat exchanger (106) is the backbone of the system and helps in operational expenditure (OPEX) reduction. It focuses to heat the process slurry from ambient condition to temperature of around 30 oC to 250 oC with the help of heat recovery from reactor product streams. As the heat of the reactor outlet stream is used for heating process slurry using the heat exchanger (106), thus the reactor (108, 109) outlet stream is cooled subsequently and is ready for de-pressurization and separation operations such as solid separation, gas-liquid separation, liquid-liquid separation the like.
The depressurization is done in stage-wise manner by employing multiple flash drums in series or combination of flash drums or using single/series of control valves or using tapered pipe or constant pressure drop element or with the help of pressure recovery turbine.
The gas-liquid separation by a gravity separator is multi-staged by using a horizontal or a vertical vessel, or multiple centrifuges or multiple chemical separation units for solvent extraction.
The liquid-liquid separation unit (116, 119) can form emulsion and thus needs to be segregated at the temperature range of 50 oC to 90 oC.
The oil storage unit (123) is provided with heat tracing and nitrogen blanketing. The oil so obtained is utilized by heat exchanger.
Referring to figure 6, the present disclosure further provides a hydrothermal liquefaction system (300) for conversion of the feed to the oil to reduce charring, wherein the feed is prepared in an arrangement comprising: a sorting and separation station (302), a shredding and separation station (304), a shredding and grinding station (308), and a homogenizer (310). The system (300) is configured to convert a plurality of the feeds to the homogenized feed having the predetermined particle size of less than 200 microns.
The system (300) minimizes the equipment required for preparation of the feed. The plurality of feed can be processed in the same set of equipment of the system (300).
In accordance with the embodiments of the present disclosure, the sorting and separation station (302) is configured to receive and segregate a municipal solid waste (MSW) (312).
In accordance with the embodiments of the present disclosure, the sorting and separation station (302) comprises a unit at least one selected from a magnetic separation unit, an eddy current separation unit and an air density separation unit.
MSW consists of the wastes such as papers, plastics, metals, non-metals, glass, soil, plant and tree waste, food waste and the like. HTL ready feed must be organic in nature with maximum 15 mass% inorganic content, which is usually ash.
MSW is collected either in closed bags or in loose condition based on the source of collection. Large size objects (both recyclable and non-recyclable) are removed at first manual sorting station at the upstream of bag opener. Closed MSW bags and other loosened MSW passes through bag opener to cut open the closed bags and disperse the MSW for further manual sorting and separation of recyclables at the second manual sorting station. The sorted MSW is fed to the magnetic separator followed by eddy current separator to remove ferrous and non-ferrous metals respectively.
In accordance with the embodiments of the present disclosure, the shredding and separation station (304) is configured to receive the segregated municipal solid waste from the sorting and separation station (302) and an agri-residue or forest waste (314) to further segregate, shred and compress the waste. The compression of the waste is performed in a baler (306).
In accordance with the embodiments of the present disclosure, the shredding and separation station (304) comprises a unit at least one selected from a magnetic separation unit, an eddy current separation unit, an air density separation unit, a dry waste shredding unit, and a wet waste shredding unit.
In accordance the embodiments of the present disclosure, the shredding and grinding station (308) is configured to receive the segregated and shredded waste from shredding and separation station (304) and a vegetable-fruit waste (320) to further reduce the size of the waste.
The metal/non-metal segregated waste is fed to the main shredder to reduce waste particle size below 10 cm. The shredded waste passes through air density separator which segregates the biodegradable and non-biodegradable content. The biodegradable portion (mostly organics) is further processed into secondary wet waste shredder for further size reduction (preferably below 5 cm) followed by grinding of waste through two stage grinders in the presence of HTL aqueous phase at a temperature in the range of 70 °C to 80 °C.
Feed (biomass or waste feedstock) is received at the plant battery limit. Large size feed stock such as lignin waste, segregated municipal waste, kitchen waste, vegetable waste and the like is fed to the shredder using conveyor belt where the waste feed is cut down into the size less than 5 cm to 8 cm. The shredded feed along with other smaller size wet feeds such as STP/ETP sludge, pulp and paper industrial waste, wet animal manure and the like is then fed to the grinder which undergoes further size reduction in the presence of recycled HTL aqueous or process water received at a temperature in the range of 20 °C to 90°C. The grinder’s output slurry particle size is not more than 100 microns.
In accordance with the embodiments of the present disclosure, the homogenizer (310) is configured to receive the waste from the shredding and grinding station (308) and a sludge (318) at least one selected from effluent treatment (ETP) and sewage treatment (STP) to homogenize the waste.
Concentration of grinded slurry is further reduced in the homogenizing or storage tank (310) to desired value in the range of 5 wt% to 30 wt% with addition of HTL aqueous or process water. Homogenizing tank utilizes agitator/mixer and closed loop circulation from positive displacement pump and inline homogenizer/ shear thinning pump for viscosity reduction and proper homogenization of biomass or waste slurry. Finally, the homogenized feed is sent to the feed storage tank (101).
The grinded waste slurry is processed through an inline homogenizer (310) consisting of a tank with anchor type mixer, a gear pump and a homogenizer pump to reduce the slurry viscosity and make it flowable and pumpable with or without the addition of HTL aqueous phase at a temperature in the range of 70 °C to 80 °C as shown in Figure 6. The discharge stream of homogenizer pump is divided into two streams: one stream going back to the homogenizer tank as recirculation and the second stream goes to the HTL system of the present disclosure.
The non-biodegradable wastes are collected through air density separator in shredding and separation station (304) are compressed in Baler machine (306) to make Refuse-derived Fuel (RDF) (316). Baler machine is a type of equipment utilized for size reduction of feed. The Baler machine is utilized mainly for agri-residue type of feed.
When the moisture content in the feed is low, the viscosity of the feed is usually high, the temperature of the feed can be increased by mixing steam/hot water to facilitate homogenizing in the homogenizer (310) of the feed preparation system (300). The homogenizing action itself also increases the temperature of feed, in some cases, the homogenization can increase the temperature of the feed in the range of 80 oC to 100 oC. The feed at temperature in the range of 80 oC to 100 oC then enter the HTL system (100, 200), which is further heated in the heat exchangers (106, 107). In accordance with the embodiments of the present disclosure, the shredding and grinding station (308) comprises a unit at least one selected from a dry waste shredding unit, a wet waste shredding unit, and a chipping unit.
When a conventional process or system has high charring, there is a high pressure drop across the heat exchangers. The occurrence of charring lead to choking of the heat exchanger tubes and process/system was able to run only for a limited time. The reduced charring in the present process/system is realized from the reduction in pressure drop across heat exchangers (106, 107). This reduction in the pressure drop led to significant improvement in the run time of the system.
The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
The present disclosure is further illustrated herein below with the help of the following experiments. The experiments used herein are intended merely to facilitate an understanding of the ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the experiments should not be construed as limiting the scope of embodiments herein. These laboratory scale experiments can be scaled up to industrial/commercial scale and the results obtained can be extrapolated to industrial/commercial scale.

EXPERIMENTAL DETAILS
Example 1
HTL feed was prepared using an algae powder such that the feed has a total solid concentration of 10% by weight. The slurry was fed to feed tank where it was stirred on a continuous basis. The feed tank outlet was connected to high pressure pump through which the slurry was pressurized to the required pressure of ~190 bar. Pressurized slurry was then passed through series of heat exchangers where the slurry temperature was increased in a stage wise manner from ambient condition to 315 oC. The heated slurry was then sent to series of CSTR type reactors where 30 minutes of residence time was given to the slurry. The product stream is then sent to high temperature (310 oC) and pressure (190 bar) for solid separation scheme the solids/hydrochar was separated from the gases, oil, aqueous and water portion by using the solid separation units (110, 112). The remaining fluids were then depressurized to 1 bar pressure and cooled down to 80 oC using an air cooler (temperature and pressure in gas-liquid separation unit (115)). Once depressurized and cooled the product mixture was sent to the gas-liquid separator where the gases taken off and the liquid stream was sent to oil-liquid separator to obtain separated oil and aqueous components dissolved with water. The trial was continued for around 27 hours. Total of 210 kg of algal powder was consumed giving a total of 51 kg of the oil.
It was observed that there was no significant pressure drop across the system, which indicated there was no significant charring of the feed during the process. There was longer runtime of the system/process as compared to the conventional system/process. For example, there was increase in run time by over 5 times as compared to conventional process/system for algal powder feed.
Examples 2-3
Trials were conducted on other feeds like algae, and ETP-STP sludge in the similar scheme as given in example 1 that also includes slurry preparation using aqueous effluent stream recycle of the HTL system of the present disclosure. Trials details are provided in the table given in Table 1.
Table 1 – Feed processed in Pilot system
Ex. No Feed material Solid concentration Reaction Temperature Reaction Pressure Feed utilized Oil produced
% (w/w) oC Bar Kg Litre
2 Algae 10 325 180-200 2380 73
3 ETP and STP sludge 10 330 180-200 390 3.25

It was observed that there was no significant pressure drop across the system, which indicated there was no significant charring of the feed during the process. There was longer runtime of the system/process as compared to the conventional system/process.
Examples 4-8
Other feeds such as kitchen and food waste,) pulp and paper industrial waste, forest residue, vegetable waste, and wheat straw were tested upon a different scheme (small pilot unit) with feed preparation system followed by feed tank and high pressure unit to achieve the desired reaction pressure of ~190 bar. The temperature here was developed using two heat exchangers in series to achieve the temperature of 330 oC to 350 oC. From the heat exchanger the slurry went to reaction system PFR and CSTR each in parallel and in series combinations. After the reaction solid was separated in solid separation unit (110, 112) at high temperature (330 oC) and pressure conditions (180-200 bar) followed by cooling and pressure let down to 80 oC and 1 bar before the product stream was sent for gas-liquid separation and liquid-liquid separation. Trials details are provided in the table 2.
Table 2 – Feed processed in Small Pilot system
Sr. No. Feed Solid concentration Reaction Temperature Reaction Pressure Feed utilized Oil produced
% wt/wt oC Bar Kg Litre
4 Kitchen and food waste 16 330 180-200 12.5 0.6
5 Pulp and paper industrial waste 10 340 180-200 4 0.1
6 Forest residue 20 350 180-200 833 83
7 Vegetable waste 20 350 180-200 833 70
8 Wheat straw 20 350 180-220 833 70

It was observed that there was no significant pressure drop across the system, which indicated there was no significant charring of the feed during the process. There was longer runtime of the system/process as compared to the conventional system/process.
Examples 9-12
More feeds such as municipal organics waste, kraft lignin biomass, rice straw, and sawdust with varying solid concentrations were tested on the system with temperature and pressure of 300 oC to 350 oC and 180 bar to 210 bar respectively. Each feed was tested with variation of residence time from 20-40 minutes. The product stream separation was carried out at low temperature pressure condition (200 oC, 18 bar) by using the solid separation unit (201). As wheat straw was similar as that of rice straw thus the results obtained from rice straw trials were extended for wheat straw also. Trials details are provided in the table 3.
Table 3 – Feed processed in batch scale system
Ex. No. Feed Solid concentration Reaction Temperature Reaction Pressure Feed utilized oil produced No. of Experiments
% (w/w) oC Bar Kg Litre Count
9 Municipal organic waste 10-21 350 180-200 4.5 0.3 17
10 Kraft Lignin biomass 15 350 180-200 0.3 0.02 8
11 Rice straw 10 350 180-200 0.43 0.13 8
12 Sawdust 15 350 180-201 1.4 0.9 12

It was observed that there was no significant pressure drop across the system, which indicated there was no significant charring of the feed during the process. There was longer runtime of the system/process as compared to the conventional system/process.
Example 13
HTL slurry was prepared using food waste such that the slurry has a total solid concentration of 20% by weight. The slurry was treated at a temperature of 315 oC and pressure of 190 bar. The required residence time of around 25 minutes to 35 minutes was provided in the reactor. The product stream was then cooled and a depressurized to a temperature of 200 oC and pressure up to 18 bar. The gas-liquid separation unit (115) was operated at a temperature of 200 oC and a pressure of 18 bar. Solids were then separated from the product stream at 200 oC and 18 bar by using the solid separation unit (201). oil and aqueous were further cooled to 40 oC and depressurized to 1 bar. Finally, oil and aqueous were separated to collect oil. Trials details are provided in the table 4.
Table 4
Ex. No. Feed Solid concentration Reaction Temperature Reaction Pressure Feed utilized Oil produced
% (w/w) oC Bar Kg L
13 Food waste 20 315 190 4.3 0.28

It was observed that there was no significant pressure drop across the system, which indicated there was no significant charring of the feed during the process. There was longer runtime of the system/process as compared to the conventional system/process.
Example 14
Shear thinning experiments were conducted with varying algal slurry concentration from 10 % (solid by wt.) to 24% using lab setup.
(a) For 10% slurry, at T=30 °C, as the shear rate is increased from 0.07 s-1 to 1500 s-1, viscosity decreases from 700 cP to 10 cP.
(b) For 15% slurry, at T=30°C, viscosity decreases from 400 cP to 330 cP in 10 min. when constant shear rate 0.07 s-1 is applied. At constant shear rate of 1500 s-1, the viscosity almost remains constant at 20 cP
(c) For 24% slurry, at T=30°C, As the shear rate is increased from 0.07 s-1 to 10 s-1, viscosity decreases from 90,000 cP to 85000 cP. Due to spill out of sample from viscometer, shear rate was increased up to 10 s-1 only. Further details are provided in Table 5:
Table 5
Effect of shear rate on algal feed Viscosity (cP)
Step-1 Shear rate(s-1) (0.07 to 1500)
0.07 10 100 500 1000 1500
10% feed slurry 700 15 7 6 9 10
15% feed slurry 1000 60 30 25 21 21
24% feed slurry 90,000 85,000
Step-2 Time (min) [Shear rate =1500 s-1]
0 2 4 6 8 10
10% feed slurry Viscosity constant at 10 cP
15% feed slurry Viscosity constant at 20 cP
24% feed slurry Viscosity almost constant at 85000 cP at the shear rate of 10s-1
Step-3 Shear Rate(s-1) (1500 to 0.07)
1500 1000 500 100 10 0.07
10% feed slurry 10 8 6 7 12 235
15% feed slurry 20 20 20 25 50 980
24% feed slurry 85,000 8,300,000

TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including, but is not limited to, the realization of
a hydrothermal liquefaction process for conversion of a feed to oil that
? provides end-to-end process;
? reduces the thermal shock faced by biomass;
? protects fluctuation in operating parameters; and
? has reduced fouling and charring;
and
a hydrothermal liquefaction system (100, 200) for conversion of a feed to oil that
? helps in improvement of the run-time of the HTL;
? increases the quality and yield of oil;
? system works with the existing equipment;
? provides end-to-end system configuration;
? reduces the thermal shock faced by biomass by using staged heating/pressurization;
? protects fluctuation in operating parameters by staged solid separation;
? reduces fouling and charring in the heat exchangers/cooling units;
? processes multiple feed simultaneously; and
? reduces the number of equipment required for the feed preparation, thereby reducing the OPEX.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or are common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation. , Claims:WE CLAIM:
1. A hydrothermal liquefaction process for conversion of a feed to oil, said process comprising the following steps:
(i) homogenizing said feed in a stage-wise manner in at least one shear thinning unit (102, 103) to obtain a homogenized feed having a predetermined solid content, a predetermined particle size and a predetermined viscosity;
(ii) pressurizing said homogenized feed in at least one pressurizing unit (105, 105’) followed by heating in at least one heat exchanger (106, 107) in a stage-wise manner to obtain a pressurized and heated slurry having a first predetermined pressure and a first predetermined temperature;
(iii) reacting said pressurized and heated slurry in at least one reactor (108, 109) at said first predetermined pressure, at said first predetermined temperature for a predetermined time period to obtain a reaction mixture containing a solid phase, a liquid phase and a gaseous phase;
(iv) selectively separating said solid phase in at least one solid separation unit (110, 112, 201), and said gaseous phase in at least one gas-liquid separation unit (115) from said reaction mixture to obtain a separated solid phase, a separated gaseous phase, and a separated liquid phase; wherein said separated liquid phase consists of an oil phase and an aqueous phase; and
(v) feeding said separated liquid phase to at least one liquid-liquid separation unit (116, 119) at a second predetermined temperature, at a second predetermined pressure to obtain a separated oil phase and a separated aqueous phase.
wherein at least a portion of said separated aqueous phase is recycled to step (i) for homogenizing said feed, and wherein said separated oil phase is said oil.
2. The process as claimed in claim 1, wherein in step (iv) said solid phase is separated in said solid separation unit (110, 112) from said reaction mixture before
a) cooling said reaction mixture in at least one heat exchanger (106, 113, 113’) to a third predetermined temperature,
b) depressurizing in at least one depressurization unit (114, 105A) to a third predetermined temperature, and
c) degasifying in said gas-liquid separation unit (115) at a fourth predetermined pressure and at a fourth predetermined temperature;
to obtain said separated solid phase, said separated gaseous phase, and said separated liquid phase consisting of said oil phase and said aqueous phase.
3. The process as claimed in claim 1, wherein in step (iv) said solid phase is separated in said solid separation unit (201) from said reaction mixture after
a) cooling said reaction mixture in at least one heat exchanger (106, 113) to said third predetermined temperature,
b) depressurizing in at least one depressurization unit (114, 105A) to said third predetermined pressure, and
c) degasifying in said gas-liquid separation unit (115) at said fourth predetermined pressure and at said fourth predetermined temperature,
to obtain said separated solid phase, said separated gaseous phase, and said separated liquid phase consisting of said oil phase and said aqueous phase.
4. The process as claimed in claim 1, wherein in step (ii) said homogenized feed is pre-heated in said heat exchanger (106) to a temperature in the range of 30 oC to 200 oC followed by heating in said heat exchanger (107) to said first predetermined temperature in the range of 250 oC to 373 oC.
5. The process as claimed in claim 1, wherein in step (ii) said homogenized feed is pre-pressurized in said pressurizing unit (105) to a pressure in the range of 0.5 bar to 20 bar and pre-heated in said heat exchanger (106) to a temperature in the range of 30 oC to 200 oC, followed by further pressurizing said homogenized feed in said pressurizing unit (105’) to said first predetermined pressure in the range of 150 bar to 250 bar and further heating in said heat exchanger (107) to said first predetermined temperature in the range of 250 oC to 373 oC.
6. The process as claimed in claims 1-3, wherein a heat dissipated during step (a) of claims 2 or 3 of cooling in said at least one heat exchanger (106, 113) is transferred to a pressurized slurry of step (ii) of claim 1 to heat the pressurized slurry.
7. The process as claimed in claims 1-3, wherein a pressure recovered during step (b) of claims 2 or 3 of depressurization in said at least one depressurization unit (114, 105A) is applied for pressurizing said homogenized feed of step (ii) of claim 1 by using a pressure recovery unit.
8. The process as claimed in claim 1, wherein prior to step (v), said separated liquid phase is further cooled in said at least one heat exchanger (113’) to a temperature in the range of 30 oC to 90 oC and transferred to said at least one liquid-liquid separation unit (116, 119) to obtain said separated oil phase and said separated aqueous phase.
9. The process as claimed in claim 1, wherein said feed is prepared from a material selected from at least one of an algal biomass, and an organic waste; wherein said organic waste is at least one selected from the group consisting of a municipal solid waste, an agri-residue, a forest waste, a vegetable-fruit waste, an effluent treatment (ETP) waste, a sewage treatment (STP) waste, a pulp and paper industrial waste, a municipal organic waste, and an industrial hydrocarbon waste.
10. The process as claimed in claim 1, wherein
• said predetermined solid content of said homogenized feed is in the range of 5 mass% to 35 mass%;
• said predetermined particle size of said homogenized feed is less than 200 micron;
• said predetermined viscosity of said homogenized feed is in the range of 5 cP to 95,000 cP;
• said first predetermined pressure in step (ii) is in the range of 150 bar to 250 bar;
• said first predetermined temperature in step (ii) is in the range of 250 oC to 373 oC;
• said predetermined time period in step (iii) is in the range of 5 minutes to 60 minutes;
• said second predetermined temperature in said at least one liquid-liquid separation unit (116, 119) in step (v) is in the range of 50 oC to 90 oC; and
• said second predetermined pressure in said at least one liquid-liquid separation unit (116, 119) of step (v) is in the range of 1 bar to 5 bar.
11. The process as claimed in claims 2 or 3, wherein
• said third predetermined temperature in said at least one heat exchanger (106, 113) of step (a) is in the range of 70 oC to 350 oC;
• said third predetermined pressure in said at least one depressurization unit (114, 105A) of step (b) is in the range of 0.5 bar to 20 bar;
• said fourth predetermined temperature in said gas-liquid separation unit (115) of step (c) is in the range of 70 oC to 220 oC; and
• said fourth predetermined pressure in said gas-liquid separation unit (115) of step (c) is in the range of 0.5 bar to 20 bar.
12. A hydrothermal liquefaction system (100, 200) for conversion of a feed to oil, said system comprises:
A. at least one shear thinning unit (102, 103) configured to receive said feed from at least one feed storage unit (101) and further configured to homogenize said feed in a stage-wise manner to obtain a homogenized feed;
B. at least one pressurization unit (105, 105’) in direct fluid communication with at least one heat exchanger (106, 107), said at least one pressurization unit (105, 105’) is configured to pressurize and heat said homogenized feed to a predetermined temperature and a predetermined pressure in a stage-wise manner;
C. at least one reactor (108, 109) configured to receive a heated and pressurized feed, at said predetermined temperature and at said predetermined pressure, from said at least one heat exchanger (107) to obtain a reaction mixture containing a solid phase, a liquid phase and a gaseous phase;
D. at least one solid separation unit (110, 112, 201) and at least one gas-liquid separation unit (115) are disposed downstream to said at least one reactor (108, 109) and are configured to separate said solid phase, said gaseous phase, and said liquid phase consisting of an oil phase and an aqueous phase;
E. at least one liquid-liquid separation unit (116, 119) is disposed downstream to said at least one gas-liquid separation unit (115) and is configured to receive said liquid phase and separate said liquid phase into said oil phase and said aqueous phase; and
F. at least one effluent storage unit (121) configured to store said aqueous phase received from said at least one liquid-liquid separation unit (116, 119) and further configured to recycle said aqueous phase to said at least one feed storage unit (101).
13. The system as claimed in claim 12, wherein said at least one solid separation unit (110, 112, 201) is selectively either
• disposed upstream to at least one heat exchanger (106, 113, 113’), at least one depressurization unit (114, 105A), and at least one gas-liquid separation unit (115);
or
• disposed downstream to the at least one heat exchanger (106, 113), said depressurization unit (114, 105A), and said at least one gas-liquid separation unit (115).
14. The system as claimed in claim 12, wherein said feed storage unit (101) is configured to receive at least a portion of said homogenized feed from said at least one shear thinning unit (102, 103); and a water tank (104) is configured to supply water to said at least one pressurization unit (105).
15. The system as claimed in claim 12, wherein said at least one heat exchanger (106) is configured to pre-heat said homogenized feed to a temperature in the range of 30 oC to 200 oC; said at least one heat exchanger (106) is in direct fluid communication with said at least one heat exchanger (107), said at least one heat exchanger (107) is configured to further heat said homogenized feed to said predetermined temperature in the range of 250 oC to 373 oC in a stage-wise manner.
16. The system as claimed in claim 12, wherein said at least one pressurization unit (105) is in fluid communication with at least one heat exchanger (106) to increase pressure and temperature of said homogenized feed to a pressure in the range of 0.5 bar to 20 bar, and to a temperature in the range of 30 oC to 200 oC in a staged manner; wherein said at least one heat exchanger (106) is in fluid communication with at least one pressurization unit (105’) to increase the pressure of said homogenized feed to a pressure in the range of 150 bar to 250 bar, and said at least one pressurization unit (105’) is in fluid communication with said at least one heat exchanger (107) to heat said homogenized feed to a temperature in the range of 250 oC to 373oC.
17. The system as claimed in claims 12 and 13, wherein said at least one solid separation unit (110, 112) is disposed upstream to said at least one heat exchanger (106, 113), said at least one depressurization unit (114, 105A) and said at least one gas-liquid separation unit (115), wherein
• said at least one solid separation unit (110, 112) is in direct fluid communication with said at least one reactor (108, 109) and is configured to receive said reaction mixture at said predetermined temperature in the range of 250 oC to 373 oC at said predetermined pressure in the range of 150 bar to 250 bar to separate said solid phase and a fluid phase containing said gaseous phase and said liquid phase;
• said at least one heat exchanger (106, 113) is configured to receive said fluid phase containing said liquid phase and said gaseous phase from said at least one solid separation unit (110, 112) and further configured to cool said fluid phase containing said liquid phase and said gaseous phase to a temperature in the range of 70 oC to 350 oC;
• said depressurization unit (114, 105A) is configured to receive said fluid phase from said at least one heat exchanger (113) and is further configured to depressurize said fluid phase to a pressure in the range of 0.5 bar to 20 bar;
• said gas-liquid separation unit (115) is configured to receive the cooled and depressurized fluid phase from said at least one depressurization unit (104), and is further configured to separate said fluid phase into said gaseous phase and said liquid phase, wherein said gas-liquid separation unit (115) supplies a stream of separated liquid phase to said liquid-liquid separation unit (116);
• said separated solid phase from said at least one solid separation unit (110, 112) is collected in a blow down pot (111).
18. The system as claimed in claims 12 and 13, wherein said at least one solid separation unit (201) is disposed downstream to said at least one heat exchanger (106, 113), said at least one depressurisation unit (114, 105A), and said at least one gas-liquid separation unit (115), wherein
• said at least one heat exchanger (106, 113) is configured to cool said reaction mixture to a temperature in the range of 90 oC to 350 oC;
• said at least one depressurization unit (114, 105A) is configured to receive the cooled reaction mixture from said heat exchanger (113) and further configured to depressurize said cooled reaction mixture to a pressure in the range of 0.5 bar to 20 bar;
• said gas-liquid separation unit (115) is configured to
i. receive said reaction mixture from said at least one depressurization unit (114); and
ii. supply a middle stream containing said liquid phase to said liquid-liquid separation unit (116); and
• said at least one solid separation unit (201) is configured to receive a bottom stream containing said solid phase and a portion of said liquid phase from said gas liquid separation unit (115).
19. The system as claimed in claims 12, 13 and 18, wherein said at least one solid separation unit (201) is configured to separate said solid phase and said portion of liquid phase from said bottom stream, and further configured to supply the separated portion of the liquid phase to said middle stream; wherein said solid phase from said at least one solid separation unit (201) is collected in a blow down pot (202).
20. The system as claimed in claim 12, wherein said oil phase from said at least one liquid-liquid separation unit (116, 119) is supplied to at least one oil storage unit (123); wherein said oil phase is said oil.
21. The system as claimed in claims 12-13 and 18-19, wherein said system further comprises at least one heat exchanger (113’) disposed downstream to said at least one solid separation unit (201) and said gas-liquid separation unit (115), said at least one heat exchanger (113’) is configured to cool said middle stream containing said liquid phase and said separated portion of liquid phase to a temperature in the range of 30 oC to 90 oC.
22. The system as claimed in claim 12, wherein said feed is prepared from a material selected from at least one of an algal biomass and an organic waste; wherein said at least one organic waste is selected from the group consisting of a municipal solid waste, an agri-residue, a forest waste, a vegetable-fruit waste, an effluent treatment (ETP) waste, a sewage treatment (STP) waste, a pulp and paper industrial waste, a municipal organic waste, and an industrial hydrocarbon waste.
23. The system as claimed in claim 12, wherein said at least one reactor (108, 109) is selected from a continuous stirred tank reactor (CSTR), a plug flow reactor (PFR), and an ebullated bed reactor (EBR).
24. The system as claimed in claim 12, wherein said at least one pressurization unit (105, 105’) is selected from the group consisting of a high pressure pump and a booster pump.
25. The system as claimed in claims 12 and 13, wherein said at least one heat exchanger (106, 107, 113, 113’) is selected from the group consisting of a shell and tube heat exchanger, a double pipe heat exchanger, a fired heater, a vessel heater, a tube and tube contact type heat exchanger, a mixing chamber, an air cooler and a water cooler.
26. The system as claimed in claim 13, wherein said at least one depressurization unit (114, 105A) is selected from the group consisting of a flash drum, a control valve, a tapered pipe, a constant pressure drop element, and a pressure recovery turbine; and said depressurization unit (105) is in fluid communication with a depressurization unit (105A) to form a pressure recovery train.
27. The system as claimed in claim 12, wherein said solid separation unit (110, 112, 201) is selected from the group consisting of a candle filter, a hydro-cyclone, a drum separator, a centrifuge, a sintered candle filter, a bag filter, a drum filter and a press filter.
28. The system as claimed in claim 12, wherein said gas-liquid separation unit (115) is selected from the group consisting of a horizontal gas-liquid separator and a vertical gas-liquid separator.
29. The system as claimed in claim 12, wherein said at least one liquid-liquid separation unit (116, 119) is selected from the group consisting of a gravity separator, a centrifuge, a coalescer, and a chemical separation unit.
30. The hydrothermal liquefaction system (300) for conversion of said feed to said oil as claimed in claims 12 and 13, wherein said feed is prepared in an arrangement comprising a sorting and separation station (302), a shredding and separation station (304), a shredding and grinding station (308), and a homogenizer (310); said system (300) is configured to convert a plurality of the feed to the homogenized feed having a predetermined particle size less than 200 microns.
31. The system as claimed in claim 30, wherein
• said sorting and separation station (302) is configured to receive and segregate a municipal solid waste (312);
• said shredding and separation station (304) is configured to receive the segregated municipal solid waste from said sorting and separation station (302) and an agri-residue or forest waste (314) to further segregate, shred and compress the waste;
• said shredding and grinding station (308) is configured to receive the segregated and shredded waste from said shredding and separation station (304) and a vegetable-fruit waste (320) to further reduce the size of the waste; and
• said homogenizer (310) is configured to receive the waste from said shredding and grinding station (308) and a sludge (318) at least one selected from effluent treatment (ETP) and sewage treatment (STP) to homogenize the waste.
32. The system as claimed in claim 30, wherein
• said sorting and separation station (302) comprises a unit at least one selected from a magnetic separation unit, an eddy current separation unit, and an air density separation unit;
• said shredding and separation station (304) comprises a unit at least one selected from a magnetic separation unit, an eddy current separation unit, an air density separation unit, a dry waste shredding unit, and a wet waste shredding unit; and
• said shredding and grinding station (308) comprises a unit at least one selected from a dry waste shredding unit, a wet waste shredding unit and a chipping unit.

Dated this 19th day of January, 2024

_______________________________
MOHAN RAJKUMAR DEWAN, IN/PA – 25
of R.K. DEWAN & CO.
Authorized Agent of Applicant

TO,
THE CONTROLLER OF PATENTS
THE PATENT OFFICE, AT MUMBAI