SYSTEMS AND PROCESSES FOR TREATMENT OF SOLUTIONS
BACKGROUND
[0001] This invention relates generally to systems and processes for treatment
of solutions. More particularly, the invention relates to systems and processes for
treatment of aqueous saline solutions using miscible organic solvents.
[0002] In industrial processes, large amounts of solutions, such as saline
solutions are produced. Generally, such aqueous saline solutions are not suitable for
direct consumption in domestic or industrial applications. In view of the limited
eligible water sources and protection of environment, some treatment processes, such
as de-ionization and desaltification for treatment of wastewater, seawater or brackish
water, become options to produce eligible water.
[0003] In current applications, various treatment processes, such as
distillation, vaporization and chemical precipitation are employed for treatment of
solutions. However, such processes can suffer from low efficiency and/or highenergy
consumption, for example, for directly treating high saline solutions, such as
fracturing water, which may prohibit them from being widely implemented.
[0004] Therefore, there is a need for new and improved systems and methods
for treatment of aqueous saline solutions, such as fracturing water.
BRIEF DESCRIPTION
[0005] A treatment system is provided in accordance with one embodiment of
the invention. The treatment system comprises a precipitation unit and a recovery
unit. The precipitation unit is configured to treat a solution using one or more
miscible organic solvents to produce a mixture of precipitate solids and a liquid. The
recovery unit is in fluid communication with the precipitation unit and configured to
facilitate separating the liquid at least into an organic phase liquid and an aqueous
phase liquid comprising a portion of the one or more miscible organic solvents. The
treatment system further comprises a purification unit comprising one or more
membrane devices in fluid communication with the recovery unit and configured to
separate at least a portion of the one or more miscible organic solvents in the aqueous
phase liquid from the aqueous phase liquid.
[0006] A treatment system is provided in accordance with another
embodiment of the invention. The treatment system comprises a precipitation unit
and a recovery unit. The precipitation unit is configured to treat a solution using one
or more miscible organic solvents to produce a mixture of precipitate solids and a
liquid. The recovery unit is in fluid communication with the precipitation unit and
configured to facilitate separating the liquid at least into an organic phase liquid and
an aqueous phase liquid comprising a portion of the one or more miscible organic
solvents. The treatment system further comprises a removal device comprising an
ionization source and a purification unit in fluid communication with the recovery
unit. The ionization source is configured to provide one or more ionization materials
to ionize at least a portion of the one or more organic solvents in the aqueous phase
liquid. The removal device is configured to receive the aqueous phase liquid to
separate at least a portion of the one or more ionized miscible organic solvents from
the aqueous phase liquid.
[0007] Another aspect of the invention further comprises a treatment process.
The treatment process comprises treating a solution using one or more miscible
organic solvents to produce a mixture of precipitate solids and a liquid, separating the
liquid at least into an organic phase liquid and an aqueous phase liquid comprising a
portion of the one or more miscible organic solvents, and introducing the aqueous
liquid into one or more of one or more membrane devices and one or more ion
removal devices to separate at least a portion of the one or more miscible organic
solvents in the aqueous phase liquid from the aqueous phase liquid.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The above and other aspects, features, and advantages of the present
disclosure will become more apparent in light of the subsequent detailed description
when taken in conjunction with the accompanying drawings in which:
[0009] FIG. 1 is a schematic diagram of a treatment system for treating
solutions in accordance with one embodiment of the invention; and
[0010] FIG. 2 is a schematic flow chart of a treatment process in accordance
with one embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0011] Embodiments of the present disclosure are described herein with
reference to the accompanying drawings. In the subsequent description, well-known
functions or constructions are not described in detail to avoid obscuring the disclosure
in unnecessary detail. As used herein, the singular forms "a," "an" and "the" include
plural referents unless the context clearly dictates otherwise.
[0012] FIG. 1 is a schematic diagram of a treatment system 10 for treating a
solution 17. In non-limiting examples, the solution 17 may comprise any saline
solution or water. In some applications, the saline solution may comprise, but not
limited to, any liquid having a salt content of at least about 2000 ppm of total
dissolved salts (TDS). In other applications, the saline solution may comprise, but not
limited to, any liquid having a salt content larger than about 10,000 ppm TDS. In one
non-limiting example, the saline water comprises fracturing water.
[0013] In embodiments of the invention, the treatment system 10 is configured
to perform the treatment, such as precipitation of salt species in the solution 17 via
using one or more miscible organic solvents to reduce concentrations of the salt
species to produce product water. It should be noted that the miscible organic solvent
is not limited to any particular miscible organic solvent, and may be selected based on
different applications.
[0014] In some applications, the miscible organic solvent may comprise amine.
In one example, the amine has the formula (a):
Alternatively, the miscible organic solvent may have the formula (b):
In the formulas (a) and (b), wherein Rl, R2 and R3 may be same or different and may
be independently selected from the group consisting of saturated or unsaturated,
branched or unbranched, substituted or unsubstituted, linear or cyclic CI-CI 4
hydrocarbons including or not including heteroatoms.
[0015] In some examples, one or more of Rl, R2 and R3 may comprise
methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, 2-methylhexyl, octyl, benzyl and
phenyl. The miscible organic solvent may include isopropylamine, propylamine,
acetone, methanol, ethanol, acetonitrile, diisopropylamine, tetrahydrofuran, dioxane,
tetrahydropyrimidine (THP), N-methyltetrahydropyrimidine (MTHP) and
combinations thereof. In one example, the miscible organic solvent comprises
diisopropylamine.
[0016] Additionally, non-limiting examples of the salt species in the solution
17 include salts selected from the group consisting of halides of sodium, calcium,
barium, strontium, and radium, bicarbonates of sodium, potassium, magnesium,
calcium, barium, strontium, and radium, silicates of sodium, potassium, magnesium,
and radium, selenites, selenates, selenides of sodium, potassium, magnesium, calcium,
barium, strontium, and radium, selenide salts selected from the group consisting of
phosphorous sub-selenide, phosphorous monoselenide, phosphorous tri-selenide, and
phosphorous penta-selenide, selenium halide salts selected from the group consisting
of selenium mono-chloride, selenium tetra-chloride, selenium mono-bromide, and
selenium tetra-bromide, phosphates of sodium, potassium, magnesium, calcium,
barium, strontium, and radium, boron salts of sodium, potassium, magnesium,
calcium, barium, strontium, and radium, sulfate salts of sodium, potassium and
radium, carbonate salts of sodium, potassium and magnesium, and combinations
thereof.
[0017] As illustrated in FIG. 1, the treatment system 10 comprises a
precipitation unit 11, a solid-liquid separation unit 12, a recovery unit 13 and a
purification unit 14. The precipitation unit 11 comprises an organic solvent source 15
and a precipitation device 16. In some embodiments, the organic solvent source 15 is
configured to provide the miscible organic solvent. The precipitation device 16 may
comprise a vessel and is configured to accommodate the solution 17 from a solution
source (not shown) and the miscible organic solvent from the organic solvent source
15. The solution 17 and the miscible organic solvent may be mixed with each other
within the precipitation device 16, so that one or more of the salt species in the
solution 17 precipitate to form a mixture of precipitate solids 1 and a liquid 19.
[0018] The solid-liquid separation unit 12 is in fluid communication with the
precipitation unit 1 1 for receiving and separating the precipitate solids 18 and a
portion of the liquid 19. The solid-liquid separation unit 12 is not limited to any
particular device suitable for separation of the precipitate solids 18 and the portion of
the liquid 19. Non-limiting examples of the solid-liquid separation unit 12 include
one or more hydrocyclones, one or more centrifuges, one or more filter presses, one
or more cartridge filters, one or more vacuum filtration devices, and one or more
microfiltration devices.
[0019] In some applications, the solid-liquid separation unit 12 may comprise
one or more hydrocyclones serially connected to each other. When the mixture of the
precipitate solids 18 and the portion of the liquid 19 from the precipitation unit 1 1 is
introduced into the solid-liquid separation unit 12, the precipitate solids 18 may be
removed from the portion of the liquid 19.
[0020] For the arrangement illustrated in FIG. 1, the recovery unit 13 is in
fluid communication with and receives the liquid 19 from the solid-liquid separation
unit 12 and an upper portion (not labeled) of the precipitation device 16. The
recovery unit 13 is configured to facilitate separation of the liquid 19, for example, to
separate a liquid with different phases.
[0021] In some examples, the recovery unit 13 may comprise a vessel, in
which the separation of the liquid 19 occurs. For example, the liquid 1 is heated and
at least separated into an aqueous phase liquid 20 and an organic phase liquid 2 1 in
the recovery unit 13. In other examples, the recovery unit 13 may comprise one or
more membrane distillation devices for separation, so that the organic phase liquid 2 1
is separated from the aqueous phase liquid 20 and recovered. In some applications,
the recovered miscible organic solvent may be reintroduced into the precipitation
device 16 for facilitating the precipitation of the salt species in other solutions.
[0022] In certain applications, after the separation in the recovery unit 13, a
portion of the miscible organic solvent is removed from the liquid 19. A certain
amount of residual miscible organic solvent may still remain in the aqueous phase
liquid 20. Accordingly, the aqueous phase liquid 20 from the recovery unit 1 may be
introduced into the purification unit 14 for the separation of at least a portion of the
residual miscible organic solvent from the aqueous phase liquid 20.
[0023] In the illustrated example, the purification unit 14 comprises a removal
device 23. The removal device 23 may comprise any devices suitable for the
separation of the residual miscible organic solvent from the aqueous phase liquid 20.
In some examples, the removal device 23 may comprise one or more membrane
devices employing one or more membranes to remove the residual organic solvent.
Non-limiting examples of the one or more membrane devices may comprise one or
more of one or more reverse osmosis devices, one or more nanofiltration devices, and
one or more membrane distillation devices.
[0024] Thus, a fluid 22 comprising at least a portion of the residual organic
solvent may be removed from the aqueous phase liquid 20, and a product liquid 24
may be produced. Alternatively, the removal device 23 may comprise one or more
ion removal devices including, but not limited to one or more ion exchange resins,
one or more reverse osmosis devices, one or more electrodialysis reversal devices,
one or more membrane distillation devices, and one or more supercapacitor
desalination devices.
[0025] In certain applications, the purification unit 14 may further comprise
an ionization source 25 disposed upstream from and in fluid communication with the
removal device 23 for providing one or more ionization materials to ionize the
residual miscible organic solvent in the aqueous phase fluid 20. In non-limiting
examples, the one or more ionization materials may comprise one or more pH
adjustment materials. As a result, before the separation of the residual organic solvent
in the removal device 23, the one or more pH adjustment materials may be introduced
to adjust the pH values of the aqueous phase liquid 20 so as to ionize at least a portion
of the residual organic solvent for facilitating the separation.
[0026] In some examples, the pH values of the aqueous phase liquid 20 may
be reduced. The one or more pH adjustment materials may comprise one or more
acids. Non-limiting examples of the one or more acids may comprise hydrochloric
acids, sulphuric acids and other suitable acids. In certain applications, the removed
residual miscible organic solvent may also be reintroduced into the precipitation unit
11.
[0027] Accordingly, due to the miscible organic solvents and the pH
adjustment materials, the salt species and the miscible organic solvents may be
removed from the solutions 17 respectively, so that the product liquid 24 is produced
with high efficiency and low energy consumption.
[0028] For the arrangement illustrated in FIG. 1, in some embodiments, the
treatment system 10 may comprise a pretreatment unit 26 disposed upstream from and
in fluid communication with the precipitation device 16. In some examples, the
pretreatment unit 26 may comprise a vessel and accommodate one or more
pretreatment materials. When the solution 1 is introduced into the pretreatment unit
26, the one or more pretreatment materials in the pretreatment unit 26 may mix with
the solution 17 to reduce the concentration of one or more ion species before the
solution 17 is introduced into the precipitation unit 11. Additionally, a pretreatment
source (not shown) may be provided separately from and provide the one or more
pretreatment materials into the pretreatment unit 26.
[0029] In some embodiments, the one or more pretreatment materials may not
be limited to any particular pretreatment materials, and may be selected based on
different ion species in the solution 17. For example, the one or more pretreatment
materials comprise one or more soluble materials having sulfate radical anions, for
example sulphuric acid, so as to remove cations, such as barium cations and/or
selenium cations in the solution 17 in the form of precipitates.
[0030] In certain applications, the treatment system 10 may further comprise
one or more heat-exchanging apparatuses 27 disposed between the pretreatment unit
26 and the precipitation unit 11, between the solid-liquid separation unit 12 and the
recovery unit 13, and/or between the recovery unit 13 and the purification unit 14 for
thermal exchange. In some applications, the recovery unit 13 may be integrated with
a heat-exchanging apparatus including, but not limited to a heater.
[0031] It should be noted that the arrangement shown in FIG. 1 is merely
illustrative. For the illustrated embodiment, the precipitation device 16 and the solidliquid
separation unit 12 are provided separately. Alternatively, the precipitation
device 16 and the solid-liquid separation unit 13 may be integrated to act as one
element for performing the precipitation and the separation.
[0032] In other examples, the pretreatment unit 26 and/or the solid-liquid
separation unit 12 may not be employed. The solution 17 may be directly introduced
into the precipitation unit 11, so that the liquid 19 at the upper portion of the
precipitation device 16 may be introduced into the recovery unit 13 after the salt
species precipitate to settle down at a lower portion of the precipitation device 16.
[0033] FIG. 2 is a schematic flow chart of a treatment process 30. As
illustrated in FIGS. 1-2, during the treatment process, in step 31, a certain amount of
the solution 17 and a certain amount of the pretreatment material are introduced into
the pretreatment unit 26 to remove one or more ion species. In step 32, the solutions
17 are then delivered into the precipitation unit 11. A certain amount of the miscible
organic solvent from the organic solvent source 15 are also introduced into the
precipitation device 16 to mix with the solution 17, so that one or more salt species
precipitate from the solutions 17 due to their lower solubility in the miscible organic
solvent and form the mixture of the precipitate solids 1 and the liquid 19.
[0034] In step 33, the precipitate solids 18 and a portion of the liquid 1 is
introduced into the solid-liquid separation unit 1 for separation. In step 34, after the
separation of the precipitate solids 18 from the portion of the liquid 19, the liquid 19
from the precipitation unit 11 and the solid-liquid separation unit 12 is introduced into
the recovery unit 13. In non-limiting examples, the liquid 19 may be heated to a
higher temperature, so that the miscible organic solvent 2 1 is separated from the
liquid 19 within the recovery unit 13 in the form of layers of the organic phase liquid
2 1 and the aqueous phase liquid 20.
[0035] Subsequently, in step 35, the aqueous phase liquid 20 is introduced
into the purification unit 14 for separation of the residual miscible organic solvent 22
from the aqueous phase liquid 20. In one non-limiting example, a certain amount of
the pH adjustment material may be mixed with and adjust the pH values of the
aqueous phase liquid 20 from the recovery unit 13 so as to ionize the residual miscible
organic solvent 22, so that the residual miscible organic solvent 22 is separated and
recovered after passing through the purification unit 14. In non-limiting examples,
the adjusted pH values of the aqueous phase liquid 20 may be about 4-5.
[0036] In some applications, the separated miscible organic solvent 2 1 in step
34 and/or the recovered residual miscible organic solvents 22 in step 35 may be
reintroduced into the precipitation device 16. In other applications, one or more heat
exchanging steps may be employed before the precipitation step 32, the solid-liquid
separation step 33, the liquid-liquid separation step 34 and/or the recovery step 35.
[0037] In non-limiting examples, prior to the precipitation step 32, the
solutions 17 may be cooled, for example, to about 0°C for the subsequent
precipitation step 32. The liquid-liquid separation step 34 may be performed at a
higher temperature, such as about 70°C. Prior to the step 35, the aqueous phase liquid
20 from the recovery unit 13 may also be cooled, for example, to about 25°C for the
recovery step 35. Additionally, in certain applications, the pretreatment step 3 1
and/or the solid-liquid separation step 33 may not be employed.
[0038] Accordingly, in embodiments of the invention, due to the presence of
the miscible organic solvent in the solution, the salt species may be removed with
lower cost and higher efficiency. In addition, the residual miscible organic solvent
may be readily removed with lower energy consumption via adjustment of the pH
values of the aqueous phase liquid so as to produce the product liquid.
[0039] While the disclosure has been illustrated and described in typical
embodiments, it is not intended to be limited to the details shown, since various
modifications and substitutions can be made without departing in any way from the
spirit of the present disclosure. As such, further modifications and equivalents of the
disclosure herein disclosed may occur to persons skilled in the art using no more than
routine experimentation, and all such modifications and equivalents are believed to be
through the spirit and scope of the disclosure as defined by the subsequent claims.
WHAT IS CLAIMED IS:
1. A treatment system, comprising:
a precipitation unit configured to treat a solution using one or more miscible
organic solvents to produce a mixture of precipitate solids and a liquid;
a recovery unit in fluid communication with the precipitation unit and
configured to facilitate separating the liquid at least into an organic phase liquid and
an aqueous phase liquid comprising a portion of the one or more miscible organic
solvents; and
a purification unit comprising one or more membrane devices in fluid
communication with the recovery unit and configured to separate at least a portion of
the one or more miscible organic solvents in the aqueous phase liquid from the
aqueous phase liquid.
2. The treatment system of claim 1, wherein the solution comprise a
saline solution.
3. The treatment system of claim 1, wherein the precipitation unit
comprises an organic solvent source and a precipitation device in fluid
communication with the organic solvent source, and wherein the organic solvent
source is configured to provide the one or more miscible organic solvents into the
precipitation device, and the precipitation device is configured to accommodate the
one or more miscible organic solvents and the solution for the precipitation of the
precipitate solids.
4. The treatment system of claim 1, wherein the one or more membrane
devices comprises one or more of one or more reverse osmosis devices, one or more
nanofiltration devices, and one or more membrane distillation devices.
5. The treatment system of claim 4, wherein the one or more membrane
devices comprise the one or more reverse osmosis devices.
6. The treatment system of claim 1, wherein the purification unit further
comprises an ionization source configured to provide one or more ionization materials
to ionize at least a portion of the one or more organic solvents in the aqueous phase
liquid so that at least a portion of the one or more ionized organic solvents are
removed using the one or more membrane devices.
7. The treatment system of claim 6, wherein the ionization source
comprises a pH adjustment source configured to provide one or more pH adjustment
materials to adjust pH values of the aqueous phase liquid so as to ionize at least the
portion of the one or more residual miscible organic solvents.
8. The treatment system of claim 1, further comprising a pretreatment
unit disposed upstream from and in fluid communication with the precipitation unit,
and configured to remove one or more ion species in the solution.
9. The treatment system of claim 1, further comprising a solid-liquid
separation unit in fluid communication with the precipitation unit and the recovery
unit for separation of the precipitation solids and the liquid.
10. The treatment system of claim 1, further comprising a plurality of heatexchanging
devices at least disposed between the precipitation unit and the recovery
unit and between the recovery unit and the purification unit.
11. A treatment system, comprising:
a precipitation unit configured to treat an solution using one or more miscible
organic solvents to produce a mixture of precipitate solids and a liquid;
a recovery unit in fluid communication with the precipitation unit and
configured to facilitate separating the liquid at least into an organic phase liquid and
an aqueous phase liquid comprising a portion of the one or more miscible organic
solvents; and
a purification unit comprising an ionization source and a removal device in
fluid communication with the recovery unit, wherein the ionization source is
configured to provide one or more ionization materials to ionize at least a portion of
the one or more organic solvents in the aqueous phase liquid, and the removal device
is configured to receive the aqueous phase liquid to separate at least a portion of the
one or more ionized residual miscible organic solvents from the aqueous phase liquid.
12. The treatment system of claim 11, wherein the precipitation unit
comprises an organic solvent source and a precipitation device in fluid
communication with the organic solvent source, and wherein the organic solvent
source is configured to provide the one or more miscible organic solvents into the
precipitation device, and the precipitation device is configured to accommodate the
one or more miscible organic solvents and the solution for the precipitation of the
precipitate solids.
13. The treatment system of claim 11, wherein the one or more miscible
organic solvents comprises one or more of isopropylamine, propylamine, acetone,
methanol, ethanol, acetonitrile, diisopropylamine, tetrahydrofuran,
tetrahydropyrimidine, N-methyltetrahydropyrimidine and dioxane.
14. The treatment system of claim 11, wherein the removal device
comprises one or more ion removal devices, and wherein the one or more ion removal
devices comprises one or more of one or more reverse osmosis devices, one or more
electrodialysis reversal devices, one or more ion exchange resins, one or more
membrane distillation devices, and one or more supercapacitor desalination devices.
15. The treatment system of claim 14, wherein the one or more ion
removal devices comprises one or more of the one or more reverse osmosis devices
and the one or more membrane distillation devices.
16. The treatment system of claim 11, wherein the ionization source
comprises a pH adjustment source configured to provide one or more pH adjustment
materials to adjust pH values of the aqueous phase liquid so as to ionize at least the
portion of the one or more organic solvents residual in the aqueous phase liquid.
17. The treatment system of claim 16, wherein one or more pH adjustment
materials comprise one or more of hydrochloric acid and sulphuric acid.
18. The treatment system of claim , further comprising a pretreatment
unit disposed upstream from and in fluid communication with the precipitation unit,
and configured to precipitate one or more ion species in the solution.
19. The treatment system of claim 11, further comprising a plurality of
heat-exchanging devices at least disposed between the precipitation unit and the
recovery unit and between the recovery unit and the purification unit.
20. The treatment system of claim 11, wherein the solution comprises
fracturing water.
2 1. A treatment process, comprising:
treating a solution using one or more miscible organic solvents to produce a
mixture of precipitate solids and a liquid;
separating the liquid at least into an organic phase liquid and an aqueous phase
liquid comprising a portion of the one or more miscible organic solvents; and
introducing the aqueous liquid into one or more of one or more membrane
devices and one or more ion removal devices to separate at least a portion of the one
or more miscible organic solvents in the aqueous phase liquid from the aqueous phase
liquid.
22. The treatment process of claim 21, wherein the one or more miscible
organic solvents comprises one or more of isopropylamine, propylamine, acetone,
methanol, ethanol, acetonitrile, diisopropylamine, tetrahydrofuran
tetrahydropyrimidine, N-methyltetrahydropyrimidine and dioxane.
23. The treatment process of claim 21, further comprising introducing one
or more ionization materials into the aqueous liquid to ionize at least a portion of the
one or more miscible organic solvents in the aqueous liquid so that at least a portion
of the one or more ionized organic solvents are removed using the one or more of one
or more membrane devices and one or more ion removal devices.
24. The treatment process of claim 23, wherein the one or more ionization
materials comprise one or more pH adjustment materials to adjust pH values of the
aqueous phase liquid so as to ionize at least the portion of the one or more organic
solvents in the aqueous phase liquid.
25. The treatment process of claim 24, wherein the one or more pH
adjustment materials comprise one or more of hydrochloric acid and sulphuric acid.
26. The treatment process of claim 21, wherein one or more of one or more
reverse osmosis devices, one or more electrodialysis reversal devices, one or more
membrane distillation devices, one or more nanofiltration devices, one or more ion
exchange resins, and one or more supercapacitor desalination devices are employed to
separate at least the portion of the one or more miscible organic solvents residual in
the aqueous phase liquid from the aqueous phase liquid.
27. The treatment process of claim 21, further pretreating the solution to
reduce concentrations of one or more ion species in the solution before the solution is
treated using the one or more miscible organic solvents.