DESC:APPARATUS AND METHOD FOR CONVERTING
SEWAGE TREATMENT PLANT AND DISTILLERY SPENT WASH SLUDGE TO CHARCOAL
PRIORITY CLAIM
[0001] This invention claims priority to provisional application 202211023704 filed 22.04.2022 titled as “Apparatus and method for converting mixed municipal solid waste to charred fuel pellets / briquettes” AND application number 202211023710 also filed 22.04.2022 titled “Apparatus and method for converting sewage treatment plant (STP) sludge to charred fuel pellets/briquettes” and incorporated by reference as if fully set forth herein.
FIELD OF INVENTION
[0002] This invention relates to the field of waste disposal. In particular, this invention relates to the field of waste sludge disposal, including disposal of sludge generated from sewage treatment plant sludge (STP), Distillery Spent Wash (DSW) and Municipal Solid Waste (MSW), refuse derived fuel (RDF), biomass, discarded tires, and sewage sludge etc. Bio coal, Charcoal, Pellets or Briquettes which may be produced as solid fuel according to the present invention may be used alongside coal as alternative fuel sources.
BACKGROUND
[0003] In today’s world of consistently increasing population and resultant increase in municipal waste, municipalities across the globe are constrained to find effective solutions to manage and control municipal solid waste (MSW), Distilled Spent Wash (DSW), and resultant sludge from sewage treatment plants (STPs) etc. Particularly in India, the exponential increase in population has not only resulted in multifold increase in STP, DSW or MSW sludge generation and the associated handling & disposal problems, but also at the same time constrained our available resources and infrastructure. The accelerated rate of population growth has caught the city planners unaware and fairly outpaced their efforts, leaving much to be desired. As a result of their unpreparedness, the municipal bodies in their
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quest to tackle the above issues, have been forced to adopt reactionary & an ad hoc based approach. This has further complicated the problems.
[0004]The rapid increase in STP, DSW or MSW sludge generation has now forced the municipalities to realize that “Dump at Landfills” approach needs to be changed at the earliest. Besides engulfing premium and scarce land resource, the landfill sites have become major cause of environmental concern. In their pursuit for having better STP, DSW or MSW sludge handling and disposal solutions, different municipalities with insufficient studies and without giving much thought to future environmental requirements, have haphazardly adopted different technologies as Waste Management Solutions.
[0005]Under the existing arrangement, resultant STP, DSW or MSW sludge is collected, sun-dried, transported and dumped at a landfill site, resulting in pollution and other environmental concerns. Moreover, additional landfill sites are required from time to time for managing the wastes.
[0006]Among various waste management methods being adopted by different agencies, the methods of power generation through incineration, composting and manufacture of RDF (Refuse Derived Fuel) have gained popularity in today’s world. However, due to ever increasing environmental challenges and with emission standards being consistently revised, new challenges are being faced by the municipalities in operating such waste management plants. Particularly the incineration-based units with high emission levels and toxic contents are being identified as generous contributors to air pollution.
[0007]Another method for sludge management is incinerating it with the help of external fuel (gas and/or solid fuel), resulting in residual ash and further ash disposal issues. This method also contributes in high emissions of toxic contents into the air and cause serious air pollution. With the emission standards consistently becoming more stringent day by day, this method poses a formidable challenge for the municipalities in operating such waste management plants.
[0008]Yet another method involves composting of the sludge generated from STP, MSW or DSW into organic fertilizers. However, such process of composting requires minimum of 20-25 days, and considerably high land area which is very
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scarce in cities and thus not so feasible to work around with. Further, the presence of heavy metals in the final composted result limits the use as fertilizers.
[0009]Similar is the problem with Distillery Spent Wash, the unwanted highly polluting residual liquid waste generated during alcohol production. Despite standards imposed on effluent quality, untreated or partially treated effluent very often finds access to watercourses. The distillery wastewater with its characteristic unpleasant odour poses a serious threat to the water quality in several regions around the globe. The ever-increasing generation of distillery spent wash on the one hand and stringent legislative regulations of its disposal on the other has stimulated the need for developing new technologies to process this effluent efficiently and economically.
[0010]Clearly, the existing waste management system is proving to be inadequate, and rapid urbanization and growth of new townships have added to the already existing inadequacies. As a result, the municipalities across the globe are now being forced to scout for alternative and more environment friendly Waste Management Technology.
[0011]In short, there is no complete green and clean Solid Waste Management Solution that ensures zero landfill requirements with minimal pollution effectively.
[0012] There is thus a need to develop and introduce an automated and green technology for direct conversion of the waste to torrefied charred output which can be used in thermal power plants along with coal.
DRAWBACKS IN PRIOR ART
[0013] Torrefaction may be generally described as a mild form of pyrolysis at temperatures typically ranging between 200 to 400 degrees Celsius. During a typical torrefaction process, the properties of the input mass may change to obtain a much better fuel quality for later combustion as fuel in boilers and furnaces for production of energy. The conventional torrefaction systems are applicable to such conventional feedstocks like biomass, wood, coal etc in batches. No such torrefaction system has ever been applied for such highly moisturized feedstock like STP, DSW or MSW sludge having moisture content as high as 80%. The
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inventor hereof has identified following drawbacks or problems in the conventional sludge management system.
[0014] None of the existing STP, DSW or MSW Sludge Management System applies Torrefaction Methods or Processes.
[0015] None of the existing STP, DSW or MSW Sludge Management System has optional/alternative use of Municipal Solid Waste (MSW) as heat source.
[0016] None of the Prior Art Torrefaction Methods or Processes provide solution for Distillery Spent Wash Sludge. None of the existing STP, DSW, or MSW Sludge Torrefaction Systems or Method or Processes or Apparatus is operating continuously 24 X 7, 365 days. None of the existing systems / processes utilizes Rotary Kiln type Reactor for Torrefaction of STP, DSW, or MSW sludge to ensure high capacities of up to 350 tons of sludge inputs per day.
[0017] None of the existing STP, DSW or MSW Sludge Management System or Method or Process or Apparatus functions in such a manner that the entire process as a whole from input to output works closely linked and integrated in a closed loop system and seems to be happening in almost completely automated sequences.
[0018] None of the existing STP, DSW or MSW Sludge Management Systems or Method or Apparatus possesses Continuous Feed and Discharge System to/from the Reactor. None of the existing STP, DSW or MSW Sludge Management System or Process or Method utilizes Air Pre-Heater and Waste Heat Recovery System for energy efficiency. None of the existing STP, DSW or MSW Sludge Management System or Process or Method can selectively vary such operational parameters like (i) retention/dwell time of the feedstock inside the reactor, (ii) process heat requirement by changing the FD Fan RPM thereby increasing or reducing combustion air flow, (iii) Process Heat requirements by increasing or reducing solid fuel feed rate into the Combustion Furnace, (iv) feed rate of material inside reactor by changing speed of the Feed System Drive Motor.
[0019] The above mentioned shortcomings, disadvantages and problems are addressed herein, as detailed below.
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SUMMARY
[0020]Accordingly, it is an object of the present invention to provide complete solution for the complete sludge generated from a STP, comprising both combustible and non-combustible fractions, to ensure zero landfill.
[0021]Another object of the invention is to provide a system that creates commercially salable product like charcoal from the waste which can be utilized alongside coal in power plants, thereby earning revenue from the process.
[0022]Another object of the invention is to provide a system that has option/alternative to use Municipal Solid Waste (MSW) as primary source of energy to meet captive heat requirements. This option drastically reduces operating cost, since there would not be any expenditure towards purchase of solid/liquid/gaseous fuel to meet process heat requirements.
[0023]Another object of the invention is to provide a solution for distillery Spent Wash Sludge. Another object of the invention is to provide a STP, DSW or MSW Sludge Management System or Method or Process or Apparatus which can operate continuously 24 X 7, of 365 days. Yet another object of the invention is to provide a STP / Distillery Spent Wash Sludge Management System or Process or Method which utilizes Air Pre-Heater and Waste Heat Recovery System for energy efficiency.
[0024]Another object of the invention is to provide a STP, DSW or MSW Sludge Management System or Process or Method which utilizes Rotary Kiln type Reactor for Torrefaction of STP, DSW or MSW sludge that can efficiently handle wide range of capacities from 10 to as high as 350 tons per day from a single reactor.
[0025] Another object of the invention is to provide a STP, DSW or MSW Sludge Management System or Process or Method which functions in such a manner that the entire process as a whole from input to output works closely linked and integrated in a closed loop system and seems to be happening in almost completely automated sequences.
[0026]Another object of the invention is to provide a STP, DSW or MSW Sludge Management System or Process or Method which possesses Continuous Feed and Discharge System to/from the Reactor.
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[0027]Yet another object of the invention is to provide a STP, DSW or MSW Sludge Management System or Process or Method which can selectively vary such operational parameters like (i) retention/dwell time of the feedstock inside the reactor, (ii) process heat requirement by changing the FD Fan RPM thereby increasing or reducing combustion air flow, (iii) Process Heat requirements by increasing or reducing solid fuel feed rate into the Combustion Furnace, (iv) feed rate of material inside reactor by changing speed of the Feed System Drive Motor.
[0028]These and other objects, features, and advantage of this invention will become apparent from the following detailed description.
BRIEF DESCRIPTION OF DRAWINGS
[0029]A more detailed understanding may be had from the following description, given by way of example in conjunction with the accompanying drawings wherein:
[0030] FIG. 1 is a schematic Flow Diagram of a STP, DSW or MSW Sludge Torrefaction System developed for conversion of sewage treatment plant sludge to charred fuel pellets/briquettes;
[0031] FIG. 2 is an Isometric View of the STP, DSW or MSW Sludge Torrefaction System;
[0032] FIG. 3 is a Rear View of the STP, DSW or MSW Sludge Torrefaction System shown in FIG. 2;
[0033]FIG. 4 is a Front Elevational View of the STP, DSW or MSW Sludge Torrefaction System shown in FIG. 2;
[0034]FIG. 5 is a Side Elevational View of the STP, DSW or MSW Sludge Torrefaction System shown in FIG. 2; and
[0035]FIG. 6 is Top Plan View of the STP, DSW or MSW Sludge Torrefaction System shown in FIG.2.
DETAILED DESCRIPTION
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[0036] Embodiments are described herein that describe a system for construction for the various elements of the invented process. The sub-assemblies/components of the invented processes described hereunder are as marked in the Figure 1.
[0037]Details of the processes of FIG. 1: The Continuous Feed System sub-process is shown as 101 in FIG. 1. A completely automated Continuous Feed System (101) comprises a flared steel inverted pyramid that connects by flange to the Rotary Kiln type Reactor inlet seal. It comprises a material infeed hopper (101), Ram/Screw Feed System (102) and VFD Drive Geared Motor (103). The hopper delivers material into the Screw/Ram Feed System which positively pushes the material into throat of the Reactor. The infeed-airlocks are mounted on top of the unit to prevent ambient air from leaking into the System.
[0038] Depending on the quality and quantity of the feedstock either Ram or Screw Feed System is selected. For low density and high moisture content feedstock Ram Feed System is preferred; and for viscous material Screw Feed System is opted. The VFD drive geared motor (103) ensures controlled feed into the Rotary Reactor, which can be varied as per requirement. The Rotary Kiln Type Reactor sub-process is shown as 104 in FIG. 1. It is designed to operate at mid to high temperatures and with low levels of ambient air infiltration, very similar to a Rotary Kiln in Cement industries. The Rotary Reactor is jacketed by another vessel (105) which provides indirect heat to the material inside for torrefaction.
[0039] The reaction is a thermal decomposition of a portion of the material within the Reactor without combustion of the material. The goal is to decompose hemi-cellulose without decomposing lignin or cellulose. There is a net energy loss that is recovered from the resulting off-gas (Torr Gas) which is combusted in the Combustion Furnace (110) providing energy for both the Torrefaction Reaction and Drying/Preheating of the feedstock. The degree of energy provided by the Torr-gas is entirely dependent on the ratio of hemi- cellulose, lignin and cellulose in the species of material being processed, and on the operating temperature and dwell time within the system. Higher operating temperatures and longer dwell result in more thermal decomposition which provides higher energy density and more
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available energy from Torr-gas but also results in a higher mass-loss of the material being processed.
[0040] The Rotary Reactor (104) is a fabricated steel drum mounted horizontally connected to the Inlet System at one end, and the Discharge System (106) at the other. It rotates around its horizontal axis running on integral steel tires and two pairs of trunnions that are mounted on the civil foundations. The drum contains a series of fixed flights. As material enters the rotating drum the flights scoop up the material and shower it across the width of the drum. Concentric inner flights catch the showering material as it falls, splitting the flow and re-showering the material. Hot gas is pulled through the drum by the Tor Gas Fan (112) and provides a kinetic energy that moves the showering material forward through the drum. Residence time of the material in the drum can be controlled by a combination of VFD controlled Geared Motor Drive rotation speed and ID Fan draft. This action also classifies material by size and density and has the effect of keeping larger pieces in the drum longer. Fans are blown through quickly, the end result being an even torrefaction of everything that passes through the drum. The showering material in the drum is an evenly dispersed resistive force to the gas; it heats and sinks the energy in the gas and helps blend the gas as it travels through the drum.
[0041] The construction of the drum is modular. Sections are designed to enable easy transport to site and are bolted together on site. The tires are stress relieved and machined weldments and have a flange and web profile for maximum strength. The trunnions are oversized nodular iron castings that are slightly softer than the tires and are therefore designed to take damage before the (more expensive) tire. The tires are mounted externally and are bolted between drum sections. This creates a balanced beam thus minimizing stresses otherwise induced by extended spans. The drum itself is a light weight, high strength concept. This is important to keep stress between the tires and trunnions at manageable levels without the use of exotic metallurgy. The strength comes from the use of channels and angles (bent the hard way) and welded to the outside of the drum shell. This keeps the shell round which adds significantly to the overall strength of the assembly. The complete structure is so rigid it can be mounted to
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the trunnions and, once correctly leveled, requires no counter-roller devices to maintain tracking. It is designed for the most extreme operating conditions.
[0042] The drum drive is by roller chain or a similar gear and pinion like system that wraps around the drum, close to the infeed end tire and running on sprocket teeth welded to the drum. The chain or the pinion is driven by VFD Drive Geared Electric Motor and gearbox and is constantly lubricated.
[0043] The External Jacket (105) around the Rotary Reactor being of Steel construction with strengthening ribs and stiffeners is refractory insulated from inside. High temperature Flue Gas from the combustion chamber (110) enters the jacket from multiple entry points, and after transferring the heat to the rotary reactor and in turn to the feedstock inside it, the flue gas exits the jacket through Air Pre-Heater (109) and ID Fan (114) to the Stack (111) and into the atmosphere. Thus, the purpose of the External Jacket is to ensure indirect transfer of heat from the heat source to the feedstock inside the reactor.
[0044] The Discharge System sub-process block 106 in FIG. 1. is a hopper / cyclone arrangement which gives a compact footprint, minimizes structural steel and reduces pressure drop when compared to more conventional arrangements. The system comprises the following: Discharge Chute, ID Fan, Control Dampers, Cooling Screw.
[0045] Torrefied material and spent gas exit the drum into a chute. This is an expansion chamber that decelerates the gas allowing the material to drop out of the gas stream. There is a deflector plate that is angled down within the chute that further helps channel material to the bottom into a material screw that traverses the base of the chute. The output material discharges into a direct water injection cooling screw, in which the material finally exits the system through an airlock.
[0046] Spent gas exits the top of the chute in a duct and sucked by the Tor Gas Fan (112). The fan is a utility grade centrifugal fan. From there it is directed to the Combustion Chamber (110). Torrefied Material from the cyclone separator is collected in a material screw and airlocks in a similar arrangement to the drop box, and finally discharged into the cooling screw. The material is subsequently
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sent through hoppers (107) for sale after material densification in briquetting machines.
[0047]The Product Storage System is shown as block 107 in FIG. 1. Material output from the Discharge System (106) is temporarily stored in an overhead hopper made of steel plates and supported on steel structure. Heavy duty hydraulic machines are installed to densify the charred carbonized output to briquettes/pellets. The high capacity hydraulically operated machines can convert 1.0 – 2.0 tons of output material into pellets/briquettes for ease of handling, transportation and storage. From here the material is pneumatically conveyed in measured quantities to the combustion chamber (110) to meet process heat requirements. The balance material can be sold in open market or to power plants.
[0048] The MSW Torrefaction System is shown as block 108 in FIG. 1. This system can be optionally/alternatively used to process Municipal Solid Waste (MSW) to charcoal, which in turn can be used as primary source of fuel in the combustion chamber to meet captive heat requirements. This drastically reduces the fuel cost to NIL, since MSW can be easily made available from the local municipality free of cost. The MSW Torrefaction System being similar to the Sludge Torrefaction System, but much smaller in terms of capacities and heat requirements. Typically, a 100 TPD STP/DSW Sludge Torrefaction System would require a 25 TPD input capacity MSW Torrifier.
[0049]In the MSW Torrefaction System, a Segregating and Shredding System is provided for just before the Continuous Feed System (101). This system segregates inerts like metals, glass, ceramics, stones, earth etc out of the process and subsequently shreds the remaining material to sizes 100 – 200 mm before feeding to the Rotary Reactor. The system essentially comprises of a) Heavy Duty Shredder to size the input unsegregated MSW to size 100 – 200 mm; b) Magnetic Separator to remove ferrous metals; c) Eddy Current Separator to remove non-ferrous metals from the system; d) Ballistic separator to remove other inerts like glass, ceramics, stones, sand, earth etc.
[0050]Air Pre-Heater block is also shown as sub-block 109 in FIG. 1. This is a part of the Heat Recovery System that utilizes waste heat from the flue gas into the atmosphere to pre heat the combustion air required to burn the fuel in the
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Combustion Furnace, which in turn results in 10 – 15% reduction in fuel consumption. The tubular construction Air Pre-Heater allows hot flue gas from the Reactor pass through the tubes and combustion air from the atmosphere to the Combustion Furnace is passed across the tubes through a FD Fan to help air get pre heated.
[0051] Flue Gas entering the Air Pre-Heater will be on the tube side, whereas the combustion air will be multiple pass on the shell side. Finned tube will ensure more surface area, resulting in higher rate of heat transfer from flue gas to air. Higher air temperature will result in proportionate reduction in fuel required for combustion, thus resulting in improved thermal efficiency of the system.
[0052] The Combustion Furnace is shown as block 110 in FIG. 1. The Combustion Furnace System can be run using a combination of fuels or Torr-gas. The system initially starts with external fuel support. Thereafter it utilizes the charred output as the primary fuel and the Torr-gas (spent gas) generated in the reactor from volatile matters used as a supplementary fuel. The Torr-gas is a by-product of the Torrefaction Process within the Rotary Reactor.
[0053] The System includes Combustion Furnace complete with refractory lined combustion chamber and FD Fan. There is a soft refractory lined carbon steel housing (combustion chamber) with air- nozzles that introduce combustion air tangentially creating a cyclonic effect in the chamber. The chamber is sized for complete combustion to minimize sparks from the system. The combustion air is controlled by individual dampers with electro- mechanical actuators to enable system tuning.
[0054] A Tor Gas Fan is shown as block 112 in FIG. 1. An Induced Draft (ID) centrifugal Fan is installed to create a negative draft inside the discharge system (106), which ensures a flow path for the volatile gases and water vapours formed inside the reactor to the combustion chamber, where this mixture of gases is combusted to gain useful heat, thereby enhancing thermal efficiency of the system by 10-15%. VFD system ensures wide range of fan speed, which can be accordingly varied to maintain fixed draft within the Discharge System.
[0055] The FD Fan is shown as block 113 in FIG. 1. Purpose of this centrifugal Forced Draft (FD) Fan is to transfer desired quantity of air from the atmosphere
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across the Air Pre-Heater (109) into the Combustion Furnace (110). The VFD fitted Drive Motor of the Fan facilitates wide range of air flow into the system, which accordingly regulates the process heat requirements.
[0056]The ID Fan is shown as block 114 in FIG. 1. This centrifugal Induced Draft (ID) Fan installed before the Stack ensures smooth flow of flue gas from the External Jacket (105) and across Air Pre-Heater (109) into the chimney and then to the atmosphere.
[0057]The following table demonstrates improved efficiency and output of the present system over conventional systems:
DESCRIPTION
UNIT
TORREFACTION
CONVENTIONAL SYSTEMS
INCINERATION
SOLAR DRYING
COMPOSTING
Assumed Input
Tons per Day
100
100
100
100
Input Moisture
%
80
80
80
80
Fuel Type
Type
MSW/Solid/Liquid/Gas
Solid/Liquid/Gas
Solar
NA
Energy Input
Gcal/Day
90
90
Solar
NIL
Energy Input Cost
Rs. Lakh/Day
6.0
(NIL for MSW)
6.0
NIL
NIL
Output
Type
Charcoal
Ash
“Class A” Solid
Compost
Output Calorific Value
Kcal/Kg
2200 – 2500
NIL
NIL
NA
Output Quantity
Tons per Day
16
10
20
10
Output Energy
Gcal/Day
35 - 40
NIL
NIL
NA
Output Revenue
Rs. Lakh/Day
0.7 – 1.0
NIL
NIL
Processing Time
Minutes/days
45 minutes
30 minutes
6 days
15 – 30 days
Land Requirement
M2
350
500
17000
50000
Weather Effect
Independent
Independent
Dependent
Dependent
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[0058]Benefits of the described system are listed but not limited to the following. The advantages listed below are only indicative in nature and provided as examples only:
a)The method or process or apparatus provides complete end to endsolution of producing charcoal from STP / Distillery Sludge whichcan be used as a solid fuel in thermal power plant boilers.
b)Unlike any other System or Method or Process or Apparatus, outputfrom this system or process can be sold as fuel to thermal powerproducing companies, which in turn generates revenues.
c)The Rotary Kiln type Reactor facilitates continuous 24X7 operations,which enables higher STP / Distillery Spent Wash Sludge handlingcapacities ranging from 10 to 350 tons of input sludge per day andrequire considerably lesser land area.
d)Efficient Waste Heat Recovery System comprising Torr Gasutilization and flue gas heat recovery in Air Pre-Heater drasticallyimprove the thermal efficiency of the system, as a result of which thefuel requirement is reduced by 10-15% as demonstrated in the abovetable.
e)Optional/alternative use of MSW as primary source of fuel to meetcaptive heat requirements. This drastically reduces the energy costfor plant operation to NIL.
f)Zero landfill requirement for STP is achieved apart from it being acleaner, healthier and greener process.
g)This system also provides a Scalability and futuristic approach tothe existing STP solutions which is completely automated and aclosed loop system.
[0059]The process described above can selectively vary on such process parameters on real time basis like retention/dwell time of the feedstock inside the reactor, degree of process heat required for the process etc. just by selectively changing such operating parameters like rotational speed of the reactor, FD Fan RPM, fuel feed rate to the Combustion Furnace and Feed System Drive Motor speed. All these result in (i) consistent and higher quality of the end product, (ii)
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efficient use of input energy, (iii) emissions lower than that prescribed under Solid Waste Management Rules, 2016.
[0060]While many embodiments of the present invention relating to the STP / Distillery Spent Wash Sludge Management System or Process or Method have been illustrated, it will be appreciated by those skilled in the art that modifications of the invention may occur however, the invention should be construed to include everything within the scope of the disclosure without departing from the invention in its broader aspects. ,CLAIMS:CLAIMS
We claim:
1.A system for converting Sewage Treatment Plant (STP) or Distillery SpentWash (DSW) Sludge or Municipal Solid Waste (MSW) to charred fueloutput, comprising:
a continuous feed system (101), a Rotary Kiln Type Reactor, a Rotary Reactor (104), an External Jacket (105), a Discharge System (106), a briquetting system (107), an Air Pre-Heater (109), a combustion furnace (110), a Tor Gas Fan (112), a Forced Draft (FD) Fan (113), an Induced Draft (ID) Fan (114),
wherein the continuous feed system (101) further comprises either ram feed or screw feed (102), depending on the feedstock quality, a flared steel inverted pyramid that connects by flange to a Rotary Kiln type Reactor inlet seal, a material infeed hopper (101), and VFD Drive Geared Motor (103);
wherein input sludge is continuously fed into the system through the continuous feed system (101) which goes through the Rotary Reactor (104) and exits as torrefied material and spent gas after torrefaction,
wherein the Discharge System (106) continuously discharges solid charred output from the bottom into a water-cooled Screw Conveyor where it is charred into charcoals by Briquetting Machines (107), and allows hot spent gases to exit from the top into a Combustion Chamber (110) through Tor Gas Fan (112), and
wherein infeed-airlocks are mounted on top of the unit to prevent ambient air from leaking into the System.
2.The system of claim 1, wherein the VFD drive geared motor (103) controlsfeed into the Rotary Reactor.
3.The system of claim 1, wherein the Rotary Reactor is jacketed by anothervessel (105) which provides indirect heat to the material inside fortorrefaction.
4.The system of claim 1, wherein the Rotary Reactor (104) is a fabricated steeldrum mounted horizontally connected to the Inlet System at one end, andDischarge System (106) at the other and reactor (104) rotates around itshorizontal axis running on integral steel tires and two pairs of trunnionsmounted on civil foundations, and the drum (104) is modular inconstruction and has sections to transport to site and be bolted; and furtherthe tires are stress relieved, have a flange and web profile for maximumstrength.
5.The system of claim 4, wherein the drum contains a series of fixed flights toscoop up material entering into the drum and shower it across the width ofthe drum.
6.The system of claim 4, wherein the drum has concentric inner flights tocatch showering material as it falls, splitting the flow and re-showering thematerial.
7.The system of claim 4 wherein hot gas is pulled through the drum (104) bythe Tor Gas Fan (112) and provides kinetic energy that moves theshowering material forward through the drum.
8.The system of claim 4, wherein the trunnions are oversized nodular ironcastings that are slightly softer than the tires and wherein the tires aremounted externally and are bolted between drum sections.
9.The system of claim 4, wherein the drum drive is a by-roller chain or asimilar gear and pinion like system that wraps around the drum, close tothe infeed end tire and running on sprocket teeth welded to the drum, andwherein the chain or the pinion is driven by VFD Drive Geared ElectricMotor (103).
10.The system of claim 1, wherein the External Jacket (105) around the RotaryReactor is of Steel construction and is refractory insulated from inside,wherein high temperature flue gas from combustion chamber (110) entersthe jacket from multiple entry points, and after transferring the heat to therotary reactor and in turn to the feedstock inside it, the flue gas exits thejacket through Air Pre-Heater (109) and ID Fan (114) to the Stack (111)and into the atmosphere.
11.The system of claim 1 wherein the Discharge System (106) is a hopper /cyclone arrangement and includes Discharge Chute, ID Fan, ControlDampers, Cooling Screw.