KR101526299B1 - Plant-foward osmosis hybrid desalination system and method - Google Patents

Abstract

The present invention relates to a method and a system of plant-forward osmosis hybrid desalination and, more specifically, a method and a system of plant-forward osmosis hybrid desalination, which are allowed to introduce a switchable polarity solution as a draw solution wherein the property of the switchable polarity solution can be changed into hydrophilic property or hydrophobic property if carbon dioxide is provided or not and accordingly design an optimal process, thereby improving efficiency of collecting the draw solution or manufacturing fresh water and reducing operation expenditure (OPEX) including energy consumption.

Description

PLANT-FOWARD OSMOSIS HYBRID DESALINATION SYSTEM AND METHOD <br> <br> <br> Patents - stay tuned to the technology PLANT-FOWARD OSMOSIS HYBRID DESALINATION SYSTEM AND METHOD

The present invention is a plant-forward osmosis hybrid desalination system and to a method, and more particularly plants from the (thermal power stations, industrial plants, fuel cell, etc.) when supplied to the heat and carbon dioxide (CO ₂₎ the process efficiency and the carbon dioxide capture efficiency To an improved hybrid positive osmosis system.

About 97% of the earth's water is seawater, which is the largest in the amount of water, but its salinity is too high to be used for domestic water or industrial water. "Desalination" of seawater has been attracting attention in order to compensate for the lack of surface water in the current situation where the water shortage is getting worse.

Desalination is a series of desalination processes that remove an adequate amount of salt to convert salty seawater into fresh water for drinking and other purposes. It is divided into fresh water, brackish water and sea water according to the concentration of salt dissolved in water.

Since the seawater contains a large amount of salty water, it is necessary to remove the salt to a certain level or more as described above in order to use it as a drinking water. Such seawater desalination methods include a membrane distillation (MD) process and a reverse osmosis membrane Recently, a Forward Osmosis technique, in which fresh water and a diluted induction solution are brought into contact with a draw solution containing seawater through an osmotic membrane, It is attracting attention.

On the other hand, exhaust gases emitted from plant facilities such as thermal power plants, industrial plants, and fuel cells contain a large amount of carbon dioxide, which affects global warming and atmospheric change, adversely affecting the environment. Accordingly, various methods have been proposed to remove the carbon dioxide contained in the exhaust gas discharged from a plant using fossil fuel as an energy source.

As a conventional technique for separating carbon dioxide from exhaust gas discharged from a plant facility, Korean Patent Laid-Open No. 10-2009-0038623 ("Carbon dioxide recovery apparatus using ammonia water and carbon dioxide recovery method using same", published on April 21, 2009) . This document discloses a method of recovering carbon dioxide in a flue gas using ammonia water. A method of exclusively supplying flue gas to the cathode of the fuel cell and separately isolating carbon dioxide in the gas discharged from the anode is disclosed. However, there is a problem that the carbon dioxide separator needs to be separately installed in the plant, which not only lowers the plant power generation efficiency but also causes an increase in the initial installation cost.

Accordingly, the applicant of the present invention collects carbon dioxide from the exhaust gas discharged from the plant through the Korea Patent No. 10-1174281 ("Fresh water and fresh water capture system using flue gas, And more particularly, to a method of hybridization, which comprises a separation unit for separating an induction solution by receiving thermal energy from a plant, a purification unit including a carbon dioxide capture unit for collecting carbon dioxide from the exhaust gas of the plant, Hybrid system has been proposed. However, this technology is limited to pyrolysis or volatile ammonia-based induced solute (specifically, ammonium bicarbonate), and water has to be additionally supplied from the outside.

In addition, the applicant of the present invention has proposed a system in which the system proposed in Korean Patent No. 10-1352521 ("Freshwater Sampling System ", published on Apr. 10, 2014) And a fuel cell device that receives power and produces electric power.

On the other hand, in Korean Patent No. 10-1245264 ("Carbon dioxide capture method including positive salt water-desalination method and positive osmosis-carbon dioxide capture hybrid system", published on March 23, 2013) And a fresh water separating unit heated to a temperature ranging from 89 to 99 ° C. The plant-positive osmosis hybrid system has been proposed.

However, all of the above-mentioned prior arts use pyrolysis and volatile substances such as ammonium bicarbonate as an inducing solute. Therefore, when water is separated from the diluted ammonium bicarbonate solution and the induction solute is recovered, the control of the heating process is not easy, There is a problem that piping is clogged due to the generation of salt, so that it is difficult to control the temperature of the piping, and there is a disadvantage that the energy consumption is high. Therefore, it is required to develop a hybrid system that links the plant and the forward osmosis process more efficiently.

Korean Patent Laid-Open No. 10-2009-0038623 ("Carbon dioxide recovery apparatus using ammonia water and carbon dioxide recovery method using the same", published on April 21, 2009) Korean Patent No. 10-1174281 ("Freshwater and CO2 capture link system using flue gas", disclosed on Aug. 9, 2012) Korean Registered Patent No. 10-1352521 ("Freshwater Sampling System", published on Apr. 10, 2014) Korean Patent No. 10-1245264 ("Carbon dioxide capture method including positive osmosis brine-desalination method and positive osmosis-carbon dioxide capture hybrid system", published on Mar. 13, 2013)

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and an object of the present invention is to provide a method of introducing a switchable polarity solution, which is hydrophilic / hydrophobic depending on whether carbon dioxide is supplied, The present invention is to provide a plant-positive osmosis hybrid desalination system and a desalination method by which the efficiency of fresh water or induction solution can be improved and the operation cost (OPEX) including energy consumption can be reduced.

In order to achieve the above-mentioned object, according to an embodiment of the present invention, there is provided a plant-positive osmosis hybrid system comprising a flue gas containing carbon dioxide from a plant 10 and desalination of seawater by a forward osmosis A desalination system, comprising: a carbon dioxide contact portion (20) for supplying the exhaust gas from the plant (10) and contacting the solution with a draw solution to convert the polarity of the induction solution into hydrophilic; A positive osmotic unit 30 for supplying the induction solution converted from the carbon dioxide contact portion 20 to the one side of the osmosis membrane 31 and supplying seawater to the other side and discharging the concentrated seawater and the diluted induction solution; By converting the polarity of the inductive solution to hydrophobic by separating the carbon dioxide in the diluted inductive solution supplied from the positive osmotic unit 30 using the thermal energy supplied from the plant 10, And a carbon dioxide separation unit 40 for liquid-liquid phase separation of water. And an induction solution recovery unit (50) for extracting the phase-separated induction solution converted into a hydrophobic state, supplying the extracted solution to the carbon dioxide contact unit (20), and discharging final production water, wherein the induction solution And is a switchable pollution solution that changes its properties according to hydrophilicity / hydrophobicity. The present invention provides a plant-positive osmosis hybrid desalination system.

At this time, the variable polarity solution may be a solution in which a tertiary amine (NR ₃ ) is added to tetrahydrofuran, and the tertiary amine is preferably tertiary amino alcohols , And the third amino alcohol is at least one or more selected from the group consisting of dimethyl ethanolamine and N-methyldiethanolamine.

(HRSG) that generates steam using the heat energy supplied from the plant 10 and supplies the generated steam to the carbon dioxide separation unit 40.

The induction solution recovery unit 50 may further include a liquid separator 51 for primarily separating the induction solution that has been converted into the hydrophobic property and phase separated; And a membrane separator 52 for secondarily separating the residual inducing solution and discharging the final produced water, and the membrane separator 52 is preferably a reverse osmosis unit.

Before the exhaust gas discharged from the plant 10 is supplied to the carbon dioxide contact portion 20, the exhaust gas and another hydrogen (H ₂ ) are supplied to the fuel cell 61 to generate electric power and to discharge the mixed gas Wherein the fuel cell (61) comprises a cathode electrode in which carbon dioxide in the exhaust gas is converted into carbonate ion, and hydrogen supplied separately from the carbonate ion to produce electric power, The fuel cell 61 is a molten carbonate fuel cell (MCFC), and the fuel cell unit 60 uses the thermal energy in the mixed gas. (HRSG) for generating steam and supplying it to the carbon dioxide separation unit 40. The steam generator (HRSG)

The fuel cell unit 60 may further include a gas-liquid separator 62 for extracting carbon dioxide from the mixed gas and supplying the carbon dioxide to the carbon dioxide contacting unit 20, And a catalytic oxidizer (63) provided upstream of the gas-liquid separator (62) for removing substances other than carbon dioxide and water in the mixed gas.

According to another aspect of the present invention, there is provided a method for desalination of seawater by a forward osmosis method, comprising: supplying an exhaust gas containing carbon dioxide from a plant (10) In the osmotic hybrid desalination method, the flue gas is supplied from the plant (10) through the carbon dioxide contact portion (20) and brought into contact with the induction solution to convert the polarity of the induction solution into hydrophilic, A carbon dioxide collecting step (S10) of supplying the carbon dioxide to one side of the regular osmosis membrane (31); A positive osmosis step (S20) of supplying seawater to the other side of the osmosis membrane (31) to discharge the concentrated seawater and the diluted induction solution through the osmosis unit (30); By separating the carbon dioxide from the diluted induction solution discharged from the osmosis unit 30 by using the thermal energy supplied from the plant 10 through the carbon dioxide separation unit 40, the polarity of the induction solution is made hydrophobic A carbon dioxide separation step (S30) of converting the inductive solution and water into liquid-liquid phase by conversion; And an induction solution recovery step (S40) for extracting the phase-separated induction solution converted into a hydrophobic state through the induction solution recovery part (50), supplying the extracted solution to the carbon dioxide contact part (20) , And the induction solution is a switchable pollution solution which is changed in hydrophilicity / hydrophobicity depending on whether carbon dioxide is supplied or not.

At this time, the derivatized solution recovery step (S40) includes a first recovery step (S41) for primarily separating the phase-separated induction solution converted into the hydrophobic state through the liquid separator (51); And a second recovery step (S42) of separating the residual induction solution through a membrane separator (52) composed of a reverse osmosis unit and discharging the final product water.

The fuel cell passing step S 1 is a fuel cell passing step S 1 in which the exhaust gas and the additional hydrogen (H ₂ ) are supplied to the fuel cell 61 to generate electric power and discharge the mixed gas before the carbon dioxide capture step S 10 (S2) for removing substances other than carbon dioxide and water from the mixed gas after the fuel cell passing step (S1) and before the carbon dioxide collecting step (S10); And a gas-liquid separating step (S3) of extracting carbon dioxide in the catalytically-oxidized gas mixture through a gas-liquid separation process and supplying the extracted gas to the carbon dioxide contacting part (20).

It is preferable that the variable polarity solution is a solution in which tertiary amine (NR ₃ ) is added to tetrahydrofuran.

As described above, the plant-fixed osmosis hybrid desalination system and method of the present invention can be applied to a positive osmosis system in which a switching polarity solution whose properties change depending on whether carbon dioxide is supplied or not is hydrophilic / hydrophobic, By integrating plant facilities into optimized processes, it is possible to significantly improve the efficiency of the desalination process and inductive solution recovery process, reduce energy consumption, process operation cost, and capture and utilize carbon dioxide in the flue gas of the plant. .

1 is a process schematic diagram of a plant-fixed osmosis hybrid desalination system according to a first embodiment of the present invention.
2 is a process schematic diagram of a plant-fixed osmosis hybrid desalination system according to a second embodiment of the present invention.
3 is a process schematic diagram of a plant-fixed osmosis hybrid desalination system according to a third embodiment of the present invention.
4 is a process flow diagram of the plant-fixed osmosis hybrid desalination method of the present invention.
5 is a schematic diagram showing the basic principle of an induction solution used in accordance with a preferred embodiment of the present invention.
6 is a graph showing the results of experiments on the suitability of an inductive solution used according to a preferred embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. Prior to the description, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and should be construed in accordance with the technical concept of the present invention.

Throughout this specification, when a member is &quot; on &quot; another member, this includes not only when the member is in contact with another member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as "including" an element, it is understood that it may include other elements as well, without departing from the other elements unless specifically stated otherwise.

The terms "first "," second ", and the like are intended to distinguish one element from another, and the scope of the right should not be limited by these terms. For example, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

In each step, the identification code is used for convenience of explanation, and the identification code does not describe the order of the steps, and each step may be performed differently from the stated order unless clearly specified in the context. have. That is, each of the steps may be performed in the same order as described, or may be performed substantially concurrently or in the reverse order.

The present invention provides a plant-positive osmosis hybrid desalination system for receiving seawater from a plant (10) and desalting the seawater in a FO method by receiving thermal energy from a flue gas containing carbon dioxide. The system of the present invention comprises a plant 10, a carbon dioxide contact unit 20, a normal osmosis unit 30, a carbon dioxide separation unit 40 and an inductive solution recovery unit 50, (Hereinafter referred to as " SPS ") in which the properties change depending on the presence or absence of hydrophobicity and hydrophobicity. 1 to 3, a process flow diagram of the plant-forward osmosis hybrid desalination system of the present invention is shown in Fig. 4 Respectively.

The key technical features of the present invention are as follows: (1) Instead of a substance such as ammonium bicarbonate (NH4HCO3) which is a pyrolysis / volatile substance which has conventionally been used in a normal osmosis process, an induction solution is replaced by SPS, (OPEX) can be saved by saving the energy that is easily and costly. ② In connection with plant facilities such as thermal power plants and fuel cells, CO2 and heat energy can be collected and optimized through this process. So that it is possible to smoothly perform the continuous osmosis process and to reduce the amount of carbon dioxide emissions, thereby being eco-friendly.

The term "plant" used throughout the present specification is a concept encompassing facilities such as thermal power plants and industrial plants, and further includes other power plant facilities such as fuel cell power plants.

The exhaust gas discharged from the plant 10 usually contains 4 to 12 wt% of carbon dioxide. If it is discharged without removing carbon dioxide, it becomes a cause of global warming phenomenon, and related regulations are being strengthened all over the world.

The exhaust gas discharged from the plant 10 may be directly supplied to the system of the present invention. However, the discharged exhaust gas may be pretreated in order to prevent failure of the system equipment and ensure a certain level of service life.

The carbon dioxide contacting portion 20 serves to convert the polarity of the induction solution into a hydrophilic state by contacting the exhaust gas discharged from the plant 10 with a draw solution to thereby collect the carbon dioxide, .

The induction solution is one of the factors that plays a key role in the cleansing process. It is a medium that plays a role of drawing fresh water from raw water because the salt concentration is higher than that of raw water such as seawater, , It is common to discharge the final product water from the diluted induction solution, collect the concentrated induction solution, and put it into the process again. Improving the performance of such an inducing solution, more specifically, ease of concentration control, ease of purchase, recovery and ease of separation from fresh water is a key key to the development of the cleansing technology.

The present invention uses a Switchable Polarity Solution (SPS), which varies in hydrophilicity / hydrophobicity depending on whether carbon dioxide is supplied as an inducing solution. More specifically, when carbon dioxide is brought into contact with the water, the water is changed into hydrophilic property to be injected into the osmosis unit to generate osmotic pressure according to the concentration difference, thereby to draw fresh water from the raw water. When the carbon dioxide is separated in the future, The SPS is easily recovered through the liquid-liquid phase separation from the diluted SPS discharged from the forward osmosis facility.

Although various types of variable polarity solutions (SPS) having such properties can be used, it is preferable to use a solution in which a tertiary amine (NR ₃ ) is added to tetrahydrofuran (THF) .

Referring to FIG. 5, in a state where THF, an organic solvent having high polarity and well mixed with water, is uniformly mixed with water, a switchable additive is added and carbon dioxide is injected to adjust the ionic strength of the solution And the phase is separated into a salt-containing water portion and a THF portion.

More specifically, when carbon dioxide is injected into a solution which does not exhibit ionicity at all, a charged species is formed to have a high ionic property. After the injection of nitrogen or air or the removal of carbon dioxide by heating, And recovered to a low-state ionic property. The reaction formula at this time is shown in the following chemical formula (1).

The present invention uses a tertiary amine as the variable polarity additive. Amines are known to be particularly effective at capturing carbon dioxide. At this time, in the case of the first amine and the second amine, since the carbamate is formed by reaction with carbon dioxide, it is difficult to convert the ionic property by heating or nitrogen / air injection, It can be used as an effective additive because it can recover the ionic property relatively easily and efficiently with no hydrogen bond-donating ability.

Various types of tertiary amines may be employed as the additive, but it is preferred to use tertiary amino alcohols, more preferably dimethylamino ethanol (2- (dimethylamino) ethanol) and N- At least one selected from the group consisting of N-methyldiethanolamine is preferably used. When the carbon dioxide is injected, the compounds form a trialkylammonium hydrogen carbonate salt and show high ionicity. When the nitrogen or the air is injected or heated, the compounds are efficiently converted into the first low ionic state Because it can restore it.

Experimental data relating to this is shown in Fig. When carbon dioxide is injected into a solution of a mixture of tertiary amino alcohol and water at a volume ratio of 1: 1 at 25 ° C, the conductivity (from about 0 mS / cm to about 22 mS / cm (TDS 13,200 to 16,400 ppm) conductivity was increased and sparging of nitrogen into the solution at 85 ° C resulted in a drop of less than 3 mS / Cm after 20 minutes. (About 1 mS / cm = 600-700 ppm). Thus, it can be confirmed that the solution has a remarkable effect on the efficiency of recovery of the inductive solution in the forward osmosis process.

The inductive solution converted into hydrophilic in the carbon dioxide contact portion 20 is supplied to one side region of the osmosis membrane 31 provided in the osmosis unit 30, and seawater as raw water is supplied to the other region, ) Is performed. At this time, the type and physical properties of the osmosis membrane 31 constituting the osmosis unit 30, the size and operating conditions of the osmosis unit 30 can be adjusted as necessary.

The seawater is concentrated and discharged while the forward osmosis step (S20) is performed in the osmosis unit (30), and the inducing solution is diluted by the fresh water absorbed from the seawater. The diluted induction solution is transferred to the carbon dioxide separation unit 40 at the downstream stage, and the carbon dioxide separation step S30 is performed.

The carbon dioxide separation unit 40 separates the gaseous carbon dioxide from the diluted induction solution, thereby performing the function of separating the liquid induction solution and the water in the liquid state in which the polarity is converted into the hydrophobic state. At this time, heat can be applied, or air or nitrogen can be supplied to separate carbon dioxide. In the case where heat is applied, separate heat energy can be supplied. However, waste heat generated in the plant 10 and heat in the exhaust gas are recovered and recycled desirable. In addition, when indirectly supplying the thermal energy supplied from the plant 10 but not indirectly, it may further include an arrangement recovery steam generator (HRSG) for generating steam and supplying it to the carbon dioxide separation unit 40.

The separated gaseous carbon dioxide may be supplied to the carbon dioxide contact portion 20 but may be separately stored and processed. The separated liquid portion is transferred to the induction solution recovery portion 50 at the subsequent stage, .

The induction solution recovery unit 50 converts the hydrophobic solution to liquid-liquid phase separation, collects the induction solution, supplies the recovered solution to the carbon dioxide contact unit 20, and discharges the final production water.

The derivatized solution recovery step S40 includes a primary collection step S41 for primarily extracting and separating the inductive solution portion in the two-phase liquid by using the liquid separator 51, (S42) of separating and removing the inducing solution remaining in the water by using a membrane and discharging the final product water. At this time, various types of membrane separation devices may be employed as the membrane separator 52, but it is preferable to use a reverse osmosis unit, considering the required degree of the final production water.

The hydrophobic inductive solution recovered through the induction solution recovery unit 50 is recovered by the carbon dioxide contact unit 20 and performs the carbon dioxide capture step S10 to complete the entire process cycle.

Hereinafter, embodiments of the plant-positive osmosis hybrid desalination system and method of the present invention will be described. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents. shall.

&Lt; Embodiment 1 > Plant-linked systems>

A process flow diagram of a desalination system according to a first embodiment of the present invention is shown in Fig. The carbon dioxide contacting portion 20 supplied with the flue gas from the plant, the osmosis unit 30, the carbon dioxide separating portion 40, the liquid separator 51, and the membrane separator 52, which are the most basic concept, And a waste heat recovery steam generator for recovering heat energy from the plant and supplying it to the carbon dioxide separation unit 40. [

&Lt; Embodiment 2 > Plant - Fuel Cell Linkage System>

A process flow diagram of a desalination system according to a second embodiment of the present invention is shown in FIG. The present embodiment is an embodiment in which the fuel cell system is further incorporated into the first embodiment. The fuel cell unit 60 is provided in an intermediate stream of a plant facility and a forward osmosis facility. The fuel cell unit 60 is supplied with the flue gas discharged from the plant 10 to produce electric power, discharges the flue gas, And the waste heat discharged therefrom is also recovered through the batch recovery steam generator and supplied to the carbon dioxide separation unit 40. In the system,

More specifically, a fuel cell 61 having a cathode electrode and an anode electrode is included, so that carbon dioxide in the exhaust gas discharged from the plant 10 is separated from carbonate ions (CO ₃ ^{2 -} ), And a fuel such as hydrogen (H ₂ ) other than the converted carbonate ion is supplied to generate power at the anode electrode, and then the mixed gas is discharged to the downstream end to perform the fuel cell passing step S 1 .

By additionally combining the fuel cell unit 60, additional power can be produced, thereby improving the overall process efficiency and being more environmentally friendly.

2, Stream 1 is a flow of the mixed gas discharged from the fuel cell 61 and is composed of 46 wt% of water (H ₂ O), 41 wt% of carbon dioxide, 4 wt% of hydrogen, 8 wt% of carbon monoxide, ₄ ) 0.4 wt% and other 0.6 wt%. Therefore, in order to extract carbon dioxide from the mixed gas and supply it to the carbon dioxide contacting portion 20 at the downstream end, a gas-liquid separating step (S3) through the gas-liquid separator 62 is required.

In this case, before carrying out the gas-liquid separation step (S3), it is preferable to carry out a catalytic oxidation step (S2) through a catalytic oxidizer (63) as a pretreatment process for removing other fuel materials except for carbon dioxide and water, It is preferable to proceed the separation step S3 more effectively.

In FIG. 2, Stream 2 has a composition of 32 wt% of water, 67 wt% of carbon dioxide and 1 wt% of other materials, except for water and other fuel materials except carbon dioxide while passing through the catalytic oxidizer 63. Stream 3 Liquid separator 62, the carbon dioxide is extracted to have a composition of 98 wt% or more of carbon dioxide. At this time, if necessary, some carbon dioxide may be separately stored and stored, and then only the remaining carbon dioxide may be supplied to the carbon dioxide contact portion 20.

&Lt; Third Embodiment. Plant - Fuel cell-linked recycling system>

A process flow diagram of a desalination system according to a third embodiment of the present invention is shown in Fig. In this embodiment, in the second embodiment, the catalytic oxidizer 63 is not provided and the fuel material is supplied to the carbon dioxide contacting portion 20 at the downstream end in a state containing the fuel material, so that a part of the gas discharged from the carbon dioxide contacting portion 20 Is recycled and supplied to the fuel cell 61. A part of the discharged gas may also be supplied to the fuel cell of another system.

3, Stream 4 is a mixed gas stream discharged from the fuel cell 61 and contains 46 wt% of water, 41 wt% of carbon dioxide, 4 wt% of hydrogen, 8 wt% of carbon monoxide, 0.4 wt% of methane gas, Stream 5 is a stream supplied to the carbon dioxide contacting portion 20 by performing gas-liquid separation directly without catalytic oxidation and containing 76 wt% of carbon dioxide, 7 wt% of hydrogen, 15 wt% of carbon monoxide, 1 wt% of methane gas, and 1 wt% %.

As a result, the exhaust gas is supplied to the carbon dioxide contacting portion 20 in a state in which the residual fuel material is contained, and the fuel materials except for the carbon dioxide are discharged from the carbon dioxide contacting portion 20. In Fig. 3, stream 6 contains fuel materials such as carbon monoxide, hydrogen, and methane gas in this flow.

As a result, residual fuel gas can be recycled without catalytic oxidation, thereby improving process operation efficiency and energy efficiency.

The present invention is not limited to the above-described specific embodiment and description, and various changes and modifications may be made by those skilled in the art without departing from the scope of the present invention as claimed in the claims. And such modifications are within the scope of protection of the present invention.

10: Plant
20: Carbon dioxide contact
30: osmosis unit
31: The osmosis membrane
40: carbon dioxide separation unit
50: induction solution recovery unit
51: liquid separator
52: membrane separator
60: Fuel cell section
61: Fuel cell
62: gas-liquid separator
63: Catalytic Oxidizer

Claims (13)

A plant-septum hybrid desalination system for receiving seawater from a plant (10) and desalination of seawater by a forward osmosis method,
A carbon dioxide contact portion 20 for supplying the exhaust gas from the plant 10 and contacting the solution with a draw solution to convert the polarity of the inductive solution to a hydrophilic state;
A positive osmotic unit 30 for supplying the induction solution converted from the carbon dioxide contact portion 20 to the one side of the osmosis membrane 31 and supplying seawater to the other side and discharging the concentrated seawater and the diluted induction solution;
By converting the polarity of the inductive solution to hydrophobic by separating the carbon dioxide in the diluted inductive solution supplied from the positive osmotic unit 30 using the thermal energy supplied from the plant 10, And a carbon dioxide separation unit 40 for liquid-liquid phase separation of water. And
An induction solution recovery unit 50 for extracting the phase-separated induction solution converted into a hydrophobic state, supplying the extracted solution to the carbon dioxide contact unit 20, and discharging final production water;
/ RTI &gt;
Wherein the induction solution is a Switchable Polarity Solution which is changed in hydrophilicity / hydrophobicity depending on whether carbon dioxide is supplied or not. The method according to claim 1,
Wherein the variable-polarity solution is a solution in which a tertiary amine (NR ₃ ) is added to tetrahydrofuran. 3. The method of claim 2,
Wherein the tertiary amine is a tertiary amino alcohol (Tertiary amino alcohols). The method of claim 3,
Wherein the third amino alcohol is at least one selected from the group consisting of dimethyl ethanolamine and N-methyldiethanolamine. The method according to claim 1,
The induced solution recovery unit (50)
A liquid separator (51) for primarily separating the phase-separated induction solution converted into the hydrophobic property; And
A membrane separator (52) for secondarily separating the residual inducing solution through the reverse osmosis unit and discharging the final product water;
Wherein the plant-to-osmosis hybrid desalination system comprises: The method according to claim 1,
Before the exhaust gas discharged from the plant 10 is supplied to the carbon dioxide contact portion 20, the exhaust gas and another hydrogen (H ₂ ) are supplied to the fuel cell 61 to generate electric power and to discharge the mixed gas And a fuel cell unit (60)
The fuel cell 61 includes a cathode electrode in which carbon dioxide in the exhaust gas is converted into carbonate ion and an anode electrode that generates electricity by reacting with hydrogen supplied separately from the carbonate ion and discharges the mixed gas Plant - a positive osmosis hybrid desalination system. The method according to claim 6,
The fuel cell unit 60 further includes an arrangement recovery steam generator (HRSG) that generates steam using thermal energy in the mixed gas and supplies the generated steam to the carbon dioxide separation unit 40 Plant - a positive osmosis hybrid desalination system. The method according to claim 6,
Further comprising a gas-liquid separator (62) for extracting carbon dioxide in the mixed gas and supplying the extracted carbon dioxide to the carbon dioxide contacting part (20). 9. The method of claim 8,
The fuel cell unit (60) further includes a catalytic oxidizer (63) provided on the upstream side of the gas-liquid separator (62) for removing substances other than carbon dioxide and water in the mixed gas. A positive osmosis hybrid desalination system. A plant-desalination hybrid desalination method for desalination of seawater by a forward osmosis method by receiving thermal energy from an exhaust gas containing carbon dioxide from a plant (10)
Permeable membrane 31 of the positive osmosis unit 30 after converting the polarity of the inductive solution into hydrophilic by supplying the exhaust gas from the plant 10 through the carbon dioxide contacting part 20 and bringing the exhaust gas into contact with the induction solution, A carbon dioxide collecting step (S10) of supplying carbon dioxide to one side;
A positive osmosis step (S20) of supplying seawater to the other side of the osmosis membrane (31) to discharge the concentrated seawater and the diluted induction solution through the osmosis unit (30);
By separating the carbon dioxide from the diluted induction solution discharged from the osmosis unit 30 by using the thermal energy supplied from the plant 10 through the carbon dioxide separation unit 40, the polarity of the induction solution is made hydrophobic A carbon dioxide separation step (S30) of converting the inductive solution and water into liquid-liquid phase by conversion; And
An induction solution recovery step (S40) for extracting the phase-separated induction solution converted into a hydrophobic state through the induction solution recovery unit (50), supplying the extracted solution to the carbon dioxide contact unit (20), and discharging final production water;
/ RTI &gt;
Wherein the induction solution is a Switchable Polarity Solution which is changed in hydrophilicity / hydrophobicity according to whether carbon dioxide is supplied or not. 11. The method of claim 10,
The induced solution recovery step (S40)
A primary collection step (S41) for primarily separating the phase-separated induction solution converted into the hydrophobic state through the liquid separator (51); And
A second recovery step (S42) of separating the remaining induction solution through a membrane separator (52) composed of a reverse osmosis unit to discharge the final product water;
Wherein the plant-to-osmotic hybrid desalination method comprises: 11. The method of claim 10,
Before the carbon dioxide capture step (S10)
It is that the exhaust gas and a separate hydrogen (H ₂₎ to the fuel cell 61 is supplied to generate electricity via a fuel cell and for discharging a mixture gas phase (S1);
Further comprising the steps of: 13. The method of claim 12,
After the fuel cell passing step (S1), before the carbon dioxide capture step (S10)
A catalytic oxidation step (S2) for removing substances other than carbon dioxide and water from the mixed gas; And
A gas-liquid separation step (S3) of extracting carbon dioxide in a catalytically oxidized gas mixture through a gas-liquid separation process and supplying the carbon dioxide to the carbon dioxide contact part (20);
Further comprising the steps of:

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