KR20120114182A - A seawater electrolysi and fuel cell complex system - Google Patents

Abstract

PURPOSE: Seawater electrolysis and a fuel cell hybrid system are provided to discharge hydrogen gas with high purity without installing a hydrogen filter. CONSTITUTION: Seawater electrolysis and a fuel cell hybrid system(100) comprise a seawater electrolysis unit(110), a seawater supply unit(120), a gas-liquid separator(130), a sodium hypochlorite storage tank(140), a moisture removing unit(150), a gas purifier(160), and a fuel cell(170). The seawater supply unit supplies seawater to the seawater electrolysis unit. The gas-liquid separator separates the electrolyzed water into the liquid and gas. The sodium hypochlorite storage tank holds a sodium hypochlorite solution separated from the gas-liquid separator. The moisture removing unit removes the moisture separated from the gas-liquid separator. The gas purifier refines the hydrogen gas with high purity from the gas without moisture. The fuel cell generates electricity by the hydrogen gas supplied from the gas purifier.

Description

Seawater electrolysis and fuel cell complex system {A SEAWATER ELECTROLYSI AND FUEL CELL COMPLEX SYSTEM}

The seawater electrolysis and fuel cell composite system of the present invention relates to a seawater electrolysis facility and a fuel cell system utilizing by-product hydrogen generated at the cathode of such seawater electrolysis facility.

If the seawater used as the cooling water system of a power plant is just introduced, the flow of microbes in the facility or the growth of algae or shellfish in the seawater may block the flow path in the pipe and seriously interfere with the flow of seawater in the system.

In addition, the seawater desalination plant or ballast water treatment requires sterilization and disinfection of microorganisms.

This problem can be overcome by installing an electrolyzer on the seawater stream of the desired system to electrolyze the seawater to produce sodium hypochlorite from the seawater and supply it to the seawater. In general, seawater electrolysis equipment removes suspended particles having large particles through a filter means and supplies them to the membrane-free electrolytic cell, and supplies DC power to the anode and cathode installed in the membrane-free electrolytic cell. A facility to produce sodium hypochlorite (NaOCl) from the components.

In more detail, first, when seawater flows into the membrane-free electrolyzer and DC power is supplied to the electrode, seawater having NaCl component of seawater is oxidized to Cl ₂ by Cl ⁻ ions at the anode as shown in Scheme 1.

At this time, water is decomposed in the cathode as in Scheme 2 to generate OH ^- ions and hydrogen gas.

Chlorine gas generated at the anode and NaOH produced at the cathode produce sodium hypochlorite (NaOCl) by the reaction of Scheme 4 in bulk. In this case, O ₂ is generated by Cl ₂ gas due to side reactions in which water is decomposed, as in Equation 5, which has a correlation with chlorine generation efficiency of the electrolytic facility.

[Reaction Scheme 1]

2Cl ^- → Cl ₂ + 2e ^-

Scheme 2

^{_{2H 2 O + 2e - → H}} 2 + 2OH -

Scheme 3

Na ^{+ +} OH ^- → NaOH

Scheme 4

2NaOH + Cl ₂ → NaClO + NaCl + H ₂ O

Scheme 5

_{2H 2 O → O 2 + 4H} + + 4e -

In such electrolytic installations, the treatment of hydrogen with the explosive risk occurring at the cathode is very important.

On the other hand, as a conventional example, a membrane-free electrolytic cell system for seawater electrolysis was used. That is, the sea water is introduced into the bottom of the non-diaphragm-type electrolytic cell composed of a series of stages, undergoes an electrolytic reaction in the electrolytic cell, and is discharged through the upper discharge part of the electrolytic cell. In this case, at least one pair of positive and negative electrodes (not shown) are installed inside the electrolytic cell, and a DC power is supplied by the rectifier between the electrodes to generate sodium hypochlorite.

The above-mentioned by-product gas generated through the electrolytic process is introduced into the final sodium hypochlorite storage tank via a pipe, and diluted in a sodium hypochlorite storage tank through dilution means such as a brower to be discharged to the atmosphere.

However, this conventional technology has a problem that by-product hydrogen that can be utilized as an energy source is discharged to the atmosphere causing resource loss.

In addition, there is a problem inherent in the risk of explosion at all times by the hydrogen released into the atmosphere.

The present invention has been made to solve the above problems, by recycling the by-product hydrogen generated from seawater electrolysis to perform power production through a fuel cell and to supply it to the power of seawater electrolysis, or to produce power as a power supply source The aim is to provide an improved seawater electrolysis and fuel cell composite system for use.

Seawater electrolysis and fuel cell composite system of the present invention for achieving the above object, the seawater electrolysis unit for electrolyzing the introduced seawater; A seawater supply unit for supplying seawater to the seawater electrolysis unit; A gas-liquid separator for separating the electrolyzed water electrolyzed in the seawater electrolytic unit into a liquid and a gas; A sodium hypochlorite storage tank for storing the sodium hypochlorite solution separated in the gas-liquid separator; A water removal unit for removing water contained in the gas component separated by the gas-liquid separator; A gas purifier for purifying hydrogen gas of high purity from the gas from which water is removed from the water removing unit; And a fuel cell for producing electric power using hydrogen gas supplied through the gas purifier.

Here, the seawater electrolytic unit, having a seawater inlet and an electrolytic water outlet, a membrane-free electrolytic cell having a positive electrode and a negative electrode therein; And a power supply unit for supplying DC power to each of the anode and the cathode.

In addition, a seawater electrolytic and fuel cell composite system according to another aspect of the present invention for achieving the above object, the seawater electrolytic unit for electrolyzing the incoming seawater; A seawater supply unit for supplying seawater to the seawater electrolysis unit; A gas-liquid separator for separating the electrolyzed water electrolyzed in the seawater electrolytic unit into a liquid and a gas; Sodium hypochlorite storage tank for storing the sodium hypochlorite solution generated in the seawater electrolysis unit; A water removal unit for removing water contained in the gas component separated by the gas-liquid separator; And a fuel cell for producing electric power by using hydrogen gas supplied through the gas-liquid separator.

Here, the seawater electrolytic unit, the diaphragm electrolytic cell divided into a cathode chamber and a cathode chamber by a diaphragm installed therein; And a power supply unit for supplying DC power to the anode chamber and the cathode chamber of the diaphragm electrolyzer, wherein each of the anode chamber and the cathode chamber has a seawater inlet port and an electrolytic water outlet port.

In addition, the cathode electrolytic water supply line for connecting the electrolytic water outlet of the cathode chamber and the gas-liquid separator; An anode electrolytic water discharge line connecting the electrolyte discharge port of the anode chamber and the sodium hypochlorite storage tank; And a cathode electrolytic water supply line connecting the liquid outlet port of the gas-liquid separator and the anode electrolytic water discharge line to supply the separated liquid to the sodium hypochlorite storage tank. And a gas supply line connected to the gas outlet of the gas-liquid separator, in which the water removal unit and the fuel cell are sequentially installed.

In addition, the cathode electrolytic water supply line for connecting the electrolytic water outlet of the cathode chamber and the gas-liquid separator; An anode electrolytic water discharge line connecting the electrolyte discharge port of the anode chamber and the sodium hypochlorite storage tank; And a cathode electrolytic water supply line connecting the liquid outlet port of the gas-liquid separator and the anode electrolytic water discharge line to supply the separated sodium bicarbonate solution to the sodium hypochlorite storage tank; A gas supply line connected to a gas outlet of the gas-liquid separator, in which the water removal unit and the fuel cell are installed in sequence; And a circulation supply unit which circulates and supplies a part of the aqueous sodium hydrogen carbonate solution separated by the gas-liquid separator to the cathode chamber.

The seawater supply unit may include a first seawater supply line for supplying seawater to the anode chamber; A first pump installed at the first sea water supply line; A filter unit installed in the first sea water supply line; A second seawater supply line for supplying seawater to the cathode chamber; And a second pump installed in the second seawater supply line, wherein the circulation supply unit is connected to the second seawater supply line.

In addition, the cathode electrolytic water supply line for connecting the electrolytic water outlet of the cathode chamber and the gas-liquid separator; An anode electrolytic water discharge line connecting the electrolyte discharge port of the anode chamber and the sodium hypochlorite storage tank; And a circulation supply unit configured to circulate and supply the aqueous sodium bicarbonate solution discharged from the liquid discharge port of the gas-liquid separator to each of the cathode chamber and the anode chamber. And a gas supply line connected to the gas outlet of the gas-liquid separator, in which the water removal unit and the fuel cell are sequentially installed.

In addition, the seawater supplied to the cathode chamber through the second seawater supply line is preferably 1 ~ 10% sodium chloride solution.

In addition, the moisture removal unit is preferably any one selected from a water removal filter, a water removal absorbent, a low temperature condensation unit.

In addition, the fuel cell is preferably a polymer electrolyte fuel cell.

In addition, the production concentration of the sodium hypochlorite solution is preferably in the range of 500 ~ 6,000ppm.

In addition, the gas-liquid separator, it is preferable that the cyclone-type gas-liquid separator.

In addition, the diaphragm may include a microporous diaphragm capable of moving an ion selective membrane or a cation as a cathode and an anion as an anode without any other ion selectivity.

In addition, the sodium hydroxide aqueous solution supplied to the cathode chamber through the circulation supply unit is preferably 1 ~ 30% of the total amount discharged from the gas-liquid separator.

According to the seawater electrolysis and fuel cell composite system of the present invention, power can be produced by utilizing hydrogen generated in seawater electrolysis, and thus resources can be recycled.

In addition, the present invention can solve the explosion risk of hydrogen, one of the biggest problems in the seawater electrolysis facility through the recycling of resources.

In addition, the present invention has the advantage that it can utilize the resources discarded by producing the power by supplying the discarded hydrogen as a raw material to the energy source of the fuel cell which is one of the renewable energy.

Brief Description of the Drawings Fig. 1 is a block diagram of a seawater electrolytic facility and a fuel cell hybrid system according to a first embodiment of the present invention.
Figure 2 is a process diagram of the seawater electrolysis facility and fuel cell composite system according to a second embodiment of the present invention.
Figure 3 is a process diagram of the seawater electrolysis facility and fuel cell composite system according to a third embodiment of the present invention.
Figure 4 is a process diagram of the seawater electrolysis facility and fuel cell composite system according to a fourth embodiment of the present invention.

Hereinafter, a seawater electrolytic and fuel cell composite system according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2, the seawater electrolysis and fuel cell composite system 100 according to the first embodiment of the present invention, the seawater electrolysis unit 110, seawater supply unit 120, gas-liquid separator 130, and A sodium chlorate reservoir 140, a water removal unit 150, a gas purifier 160, and a fuel cell 170 are provided.

The seawater electrolytic unit 110 includes only an electroless tank 111 and a power supply 113. The diaphragm electrolyzer 111 has a seawater inlet 111a and an electrolyzed water outlet 111b, and is provided with an anode and a cathode not shown therein. Therefore, when a DC current is supplied from the power supply 113 to the anode and the cathode in the membrane-free electrolyzer 111, each of the anode and the cathode electrolyzes the introduced seawater to generate decomposed water. That is, as described above through Reaction Schemes 1 to 5, sodium hypochlorite is generated by the electrolysis of seawater in the membrane-free electrolyzer 111, and oxygen, chlorine and hydrogen gas are generated due to side reactions.

Here, the power supply unit 113 is configured to include a rectifier for converting and supplying alternating current to direct current. The electrolytic water outlet 111b is supplied to the gas-liquid separator 130 by the electrolytic water supply line 118.

In addition, the diaphragm electrolyzer 110 may have a structure in which mesh or plate-shaped electrodes are alternately arranged in an electrolytic cell of a substantially rectangular parallelepiped, and in addition to the configuration of a cylindrical electrolytic cell in which cylindrical electrodes having different circumferences are arranged on concentric circles. May have As described above, it is to be understood that the non-diaphragm electrolyzer 110 may have various shapes and structures.

The seawater supply unit 120 includes a supply pump 122 installed on the seawater supply line 121 and a filter unit 123 installed on the seawater supply line 121. Therefore, by using the feed pump 122, the seawater is forcibly pumped and supplied along the seawater supply line 121 to the membrane-free electrolyzer 111. In addition, the seawater supplied along the seawater supply line 121 is filtered by impurities in the filter unit 123 and supplied to the membrane-free electrolyzer 111. The filter unit 123 may include a screen, a filter, a strainer, and the like, which filters the suspended matter from the inflowing seawater.

The gas-liquid separator 130 is for separating the decomposed water electrolyzed in the membrane-free electrolytic cell 110 and the gas generated during electrolysis. The gas-liquid separator 130 is installed in the separator body 131, the separator body 131, and the inlet 132 through which the electrolytic water is introduced, and the liquid discharge port 133 installed in the separator body 131 to discharge the separated liquid. And a gas outlet 134 for discharging the separated gas. The gas-liquid separator 130 may include a cyclone gas-liquid separator.

The liquid outlet 133 is connected to the sodium hypochlorite storage tank 140 by the sodium hypochlorite supply line 141. Therefore, the liquid separated from the gas-liquid separator 130, that is, sodium hypochlorite solution is supplied to the reservoir 140 and stored.

A gas supply line 119 is connected to the gas outlet 134, and a water removal unit 150, a gas purifier 160, and a fuel cell 170 are sequentially connected to the gas supply line 119.

The gas separated from the gas-liquid separator 130, that is, hydrogen gas and oxygen, is discharged through the gas outlet 134 together with a small amount of water and moved to the moisture remover 150. Here, some of the moisture that is not completely removed from the gas-liquid separator 130 is completely removed from the water removal unit 150 so that only pure gas components are supplied to the gas purifier 160 through the water removal unit 150.

Here, the water removal unit 150 is for removing a small amount of water that is not separated from the gas-liquid separator 130, and may include a water removal filter, a water removal adsorbent, a water absorption device by a low temperature condensation method, and the like. In addition to the above, various known water removing means may be applied.

The gas purifier 160 is to remove unnecessary impurity gas from the gas components moved along the gas supply line 119, and may include an adsorbent, a gas separation membrane, and the like. That is, in the gas purifier 160, only pure hydrogen gas is discharged from oxygen and hydrogen gas included in the mixed gas, and the remaining oxygen and other impurities are removed and treated by adsorption or the like.

The gas purifier 160 purifies and supplies hydrogen with high purity, and is preferably discharged by maintaining it at 95% or more, which is more than the hydrogen explosion limit range.

The fuel cell 170 receives high purity hydrogen gas to generate electric power through reaction with hydrogen gas, and generates water and heat as by-products. The fuel cell 170 is preferably a polymer electrolyte fuel cell. Since the configuration of the fuel cell 170 and the power generation method using the fuel cell can be understood from a known technology, detailed configurations will be omitted. In the fuel cell 170, however, the supplied high purity hydrogen gas produces electrical energy through a chemical reaction with oxygen, and simultaneously generates water and heat. Therefore, water and heat other than the generated electric energy can be treated to be discharged to the outside.

On the other hand, the production concentration of the sodium hypochlorite solution in the above configuration is preferably to maintain an effective chlorine concentration of 500 ~ 6,000ppm, more preferably to maintain an effective chlorine concentration of 1,000 ~ 2,000ppm. At this time, the amount of sodium hypochlorite solution can be increased at 500ppm or less, thereby burdening the facility, and at 6,000ppm or higher, the current efficiency is lowered. Accordingly, the negative electrode scale accumulation by the hardness material in seawater is excessive, and the cleaning cycle of the cathode is increased. It becomes short, and since the amount of hydrogen generated per unit time generated at the cathode increases to increase the size of the subsequent equipment and the fuel cell, it is preferable to maintain the effective chlorine concentration of the sodium hypochlorite solution within the above range (500 to 6,000 ppm). The effective chlorine concentration of such sodium hypochlorite solution is made possible by controlling the concentration of the supplied seawater.

As described above, according to the seawater electrolysis and fuel cell composite system 100 according to the first embodiment of the present invention, by-product gas, that is, hydrogen gas generated in the process of generating sodium hypochlorite solution by electrolyzing seawater It can be used to produce power without discarding. Therefore, there is an advantage that can be used as a resource by recycling the discarded hydrogen gas.

In addition, since the explosion risk of hydrogen, which was one of the biggest problems of seawater electrolysis facilities, can be solved through the recycling of resources, it is possible to expect the advantages of recycling resources while ensuring safety, and to generate and supply electric power, thus using energy. This has the advantage of reducing costs.

2, the seawater electrolysis and fuel cell composite system 200 according to the second embodiment of the present invention, the seawater electrolysis unit 210, seawater supply unit 220, gas-liquid separator 230, A sodium chlorate reservoir 240, a water removal unit 250, a gas purifier 260, and a fuel cell 270 are provided.

The seawater electrolytic unit 210 includes a diaphragm electrolyzer 211 and a power supply unit 213. The diaphragm electrolyzer 211 is divided into an anode chamber 210a and a cathode chamber 210b by a diaphragm 215. An anode 216 is provided in the anode chamber 210a and a cathode 217 is provided in the cathode chamber 210b. The anode chamber 210a is provided with a seawater inlet 211a and an electrolytic water outlet 211b, and a seawater inlet 212a and an electrolytic water outlet 212b are also provided in the cathode chamber 210b, respectively. The diaphragm 215 may include a microporous diaphragm such as an ion selective membrane or a microporous ceramic filter having no ion selectivity (positive ions are negative and negative ions are able to move to the positive electrode) or microporous bicore. Can be.

According to the above configuration, when a direct current is supplied from the power supply 213 to each of the anode 216 and the cathode 217, each of the anode 216 and the cathode 217 electrolyzes the introduced seawater to decompose water. Will generate

That is, in the anode chamber 210a, the seawater is electrolyzed to generate sodium hypochlorite and oxygen gas, and the sodium hypochlorite and oxygen gas thus generated are stored in the sodium hypochlorite storage tank through the anode electrolytic water discharge line 218a. 240).

In the cathode chamber 210b, the seawater is electrolyzed to generate sodium hydroxide and hydrogen gas, and the sodium hydroxide solution and the hydrogen gas thus generated are supplied to the gas-liquid separator 230 through the cathode electrolytic water discharge line 218b. do. Here, since the details of the electrolysis of seawater in the diaphragm electrolyzer 210 are well-known techniques, detailed descriptions thereof will be omitted.

The power supply unit 213 includes a rectifier and supplies a DC current to each of the anode 216 and the cathode 217.

The seawater supply unit 220 includes a supply pump 222 installed on the seawater supply line 221 and a filter unit 223 installed on the seawater supply line 221. Therefore, seawater is forcibly pumped and supplied along the seawater supply line 221 to the anode chamber 210a and the cathode chamber 210b of the diaphragm electrolyzer 211 using the supply pump 222. In addition, the seawater supplied along the seawater supply line 221 is filtered by impurities in the filter unit 223 and supplied to the diaphragm electrolyzer 211. The filter unit 223 may include a screen, a filter, a strainer, and the like, for filtering the suspended solids from the influent seawater.

The gas-liquid separator 230 is for separating the decomposed water electrolyzed in the cathode chamber 210b of the diaphragm electrolyzer 210 and the gas generated during electrolysis. The gas-liquid separator 230 is provided with a separator main body 231, a separator main body 231, an inlet 232 through which electrolytic water is introduced, and a liquid discharge port 233 installed at the separator main body 231 to discharge the separated liquid. And a gas outlet 234 for discharging the separated gas. The gas-liquid separator 230 may include a cyclone gas-liquid separator.

The liquid outlet 233 is connected to the anode electrolytic water discharge line 218a, that is, sodium hypochlorite supply line by the cathode electrolytic water supply line 241. Therefore, the negative electrode electrolyzed water, that is, the sodium hydroxide aqueous solution separated from the gas-liquid separator 230 is supplied to the storage tank 240 and stored.

A gas supply line 219 is connected to the gas outlet 234, and a water removal unit 250 and a fuel cell 270 are sequentially connected to the gas supply line 219.

Here, the water removal unit 250 is to remove a small amount of water that is not separated from the gas-liquid separator 230, and may include a water removal filter, a water removal adsorbent, a water absorption device by a low temperature condensation method, and the like. In addition to the above, various known water removing means may be applied.

The high purity gas from which the water is removed from the water removal unit 250, that is, hydrogen gas, is supplied to the fuel cell 270. Here, unlike the first embodiment of FIG. 1, in the second embodiment, a gas purifier is unnecessary, and the reason is that the electrolytic water solution in which oxygen gas is generated is electrolyzed using the diaphragm electrolyzer 211, and thus, the anode chamber 210a. This is because the impurity gas such as oxygen gas is not included in the gas supply line 219 because it is directly supplied to the sodium hypochlorite storage tank 240.

Therefore, the hydrogen gas passing through the water removal unit 250 is high purity, and as described above, is maintained at 95% or more, which is equal to or greater than the hydrogen explosion limit range and is supplied to the fuel cell 270. Since the fuel cell 270 has the same configuration and function as the fuel cell 170 described with reference to FIG. 1, a detailed description thereof will be omitted.

As described above, the seawater electrolysis and fuel cell composite system 200 according to the second embodiment of the present invention is generated during electrolysis by using the seawater electrolysis unit 210 including the diaphragm electrolyzer 211. By classifying and discharging hydrogen gas, oxygen gas, and the like among the gases, high-purity hydrogen gas may be discharged from the gas discharge line 219 to produce power in the fuel cell 270.

Referring to FIG. 3, the seawater electrolysis and fuel cell composite system 300 according to the third embodiment of the present invention includes a seawater electrolysis unit 310, a seawater supply unit 320, a gas-liquid separator 330, and an embryo. A sodium chlorate reservoir 340, a water removal unit 350, a fuel cell 370, and a circulation supply unit 380 are provided.

The seawater electrolysis unit 310 has the same configuration as the seawater electrolysis unit 210 described above with reference to FIG. That is, the seawater electrolytic unit 310 includes a diaphragm electrolyzer 311 and a power supply unit 313.

The diaphragm electrolyzer 311 is divided into an anode chamber 310a and a cathode chamber 310b by a diaphragm 315. An anode 316 is installed in the anode chamber 310a, and a cathode 317 is installed in the cathode chamber 310b. The anode chamber 310a is provided with a seawater inlet 311a and an electrolyzed water outlet 311b, and the cathode chamber 310b is provided with a seawater inlet 312a and an electrolyte water outlet 312b, respectively. The diaphragm 315 may include an ion selective membrane or a microporous diaphragm such as a microporous ceramic filter or a microporous bicore, which does not have a separate ion selectivity (positive ions may move to a cathode and an anion may move to an anode). can do.

According to the above configuration, when a DC current is supplied from the power supply unit 313 to each of the anode 316 and the cathode 317, each of the anode 316 and the cathode 317 electrolyzes the introduced seawater to decompose water. Will generate

That is, in the anode chamber 310a, the seawater is electrolyzed to generate sodium hypochlorite and oxygen gas, and the sodium hypochlorite solution thus generated is stored in the sodium hypochlorite storage tank 340 through the anode electrolytic water discharge line 218a. Is supplied.

In the cathode chamber 310b, seawater is electrolyzed to generate sodium hydroxide solution and hydrogen gas, and the sodium hydroxide solution and gas generated as described above are supplied to the gas-liquid separator 330 through the cathode electrolytic water discharge line 318b. do. Here, since the specific content by the electrolysis of seawater in the diaphragm electrolyzer 310 is a well-known technique, detailed description is abbreviate | omitted.

The power supply unit 313 includes a rectifier and supplies a DC current to each of the anode 316 and the cathode 317.

The seawater supply unit 320 may include a first seawater supply line 321 for supplying seawater to the anode chamber 310a of the diaphragm electrolyzer 310, and a first pump installed in the first seawater supply line 321. 322, a filter unit 323, a second seawater supply line 324 for supplying seawater to the cathode chamber 310b, and a second pump 325 installed in the second seawater supply line 324. do. That is, the seawater supply unit 320 is configured to independently supply seawater to each of the anode chamber 310a and the cathode chamber 310b of the diaphragm electrolyzer 311.

The gas-liquid separator 330 is connected to a cathode electrolytic water discharge line 318b to which electrolyzed electrolytic water is supplied from the cathode chamber 310b to separate the liquid electrolytic solution by gas-liquid separation of liquid (sodium hydroxide solution and hydrogen gas). The gas-liquid separator 330 has the same configuration as the gas-liquid separator 230 described above with reference to FIG. 2, that is, the separator main body 331, the separator main body 331, the inlet 332 through which the electrolytic water is introduced, and the separator main body 331. It is provided with a liquid discharge port 333 for discharging the separated liquid and the gas discharge port 334 for discharging the separated gas, such gas-liquid separator 330 may include a cyclone-type gas liquid separator.

The liquid outlet 333 is connected to the sodium hypochlorite reservoir 340 by a sodium hydroxide supply line 341. In addition, the circulation supply unit 380 is connected to the sodium hydroxide supply line 341 to re-supply some sodium hydroxide solution to the cathode chamber 310b through the second seawater supply line 324.

The circulation supply unit 380 may include a circulation line branched from the sodium hydroxide supply line 341 and connected to the second seawater supply line 324. The sodium hydroxide solution circulated to the cathode chamber 310b through the circulation supply unit 380 is preferably set to 10 to 90% of the total amount discharged from the gas-liquid separator 330. For example, at 10% or less, the purpose of excluding the movement of the scale material from the anode chamber 310a to the cathode chamber 310b by increasing the ion concentration of the cathode chamber 310b through recycling may be achieved. This is because the sodium hypochlorite solution produced at the positive electrode is present in the corrosive chlorine state due to the low pH even when mixed with the sodium hydroxide solution of some negative electrodes. Therefore, preferably, the circulation supply amount of the sodium hydroxide solution can be configured to be 50 to 60%.

On the other hand, a gas supply line 319 is connected to the gas outlet 334 of the gas-liquid separator 330, and the water removal unit 350 and the fuel cell 370 are sequentially connected to the gas supply line 319. . Since the configuration and operation effects of the moisture removal unit 350 and the fuel cell 370 are the same as those described above with reference to FIGS. 1 and 2, detailed descriptions thereof will be omitted.

On the other hand, the sea water, that is, the aqueous sodium chloride solution supplied to the cathode chamber 310b is preferably injected at a concentration of 1 ~ 10%. That is, in an aqueous sodium chloride solution of 1% or less, the operating voltage is increased to increase the unit power, and at 10% or more, it increases the operating cost by increasing the sodium chloride consumption.

4, the seawater electrolysis facility and fuel cell composite system 400 according to the fourth embodiment of the present invention includes a seawater electrolysis unit 410, a seawater supply unit 420, and a gas-liquid separator 430. And a sodium hypochlorite storage tank 440, a water removal unit 450, a fuel cell 470, and a circulation supply unit 480.

The seawater electrolysis unit 310 has the same configuration as the seawater electrolysis unit 210 described above with reference to FIG. That is, the seawater electrolytic unit 410 includes a diaphragm electrolyzer 411 and a power supply unit 413.

The diaphragm electrolyzer 411 is divided into an anode chamber 410a and a cathode chamber 410b by a diaphragm 415. An anode 416 is installed in the anode chamber 410a, and a cathode 417 is installed in the cathode chamber 410b. The anode chamber 410a is provided with a seawater inlet 411a and an electrolytic water outlet 411b, and the seawater inlet 412a and an electrolytic water outlet 412b are also provided in the cathode chamber 410b, respectively. The diaphragm 415 may include an ion selective membrane or a microporous diaphragm such as a microporous ceramic filter or a microporous bicore, which does not have a separate ion selectivity (positive ions may move to a cathode and an anion may move to an anode). can do.

According to the above configuration, when a DC current is supplied from the power supply unit 413 to each of the anode 416 and the cathode 417, the anode 416 and the cathode 417 respectively decompose the introduced seawater to decompose water. Will generate

That is, in the anode chamber 410a, the seawater is electrolyzed to produce sodium hypochlorite and oxygen gas, and the sodium hypochlorite solution thus generated is stored in the sodium hypochlorite storage tank 440 through the anode electrolytic water discharge line 418a. Is supplied.

In the cathode chamber 410b, seawater is electrolyzed to produce sodium hydroxide solution and hydrogen gas, and the sodium hydroxide solution and gas generated as described above are supplied to the gas-liquid separator 430 through the cathode electrolytic water discharge line 418b. do. Here, since the specific content by the electrolysis of seawater in the diaphragm electrolyzer 410 is a well-known technique, detailed description is abbreviate | omitted.

The power supply unit 413 includes a rectifier and supplies a DC current to each of the anode 416 and the cathode 417.

The seawater supply unit 420 may include a first seawater supply line 421 for supplying seawater to the anode chamber 410a of the diaphragm electrolyzer 410, and a first pump installed in the first seawater supply line 421. 422, a filter unit 423, a second seawater supply line 424 for supplying seawater to the cathode chamber 410b, and a second pump 425 installed in the second seawater supply line 424. do. That is, the seawater supply unit 420 is configured to independently supply seawater to each of the anode chamber 410a and the cathode chamber 410b of the diaphragm electrolyzer 410.

The gas-liquid separator 430 is connected to a cathode electrolytic water discharge line 418b to which the electrolytic cathode electrolytic water is supplied from the cathode chamber 410b, and the liquid electrolyte (sodium hydroxide solution) and hydrogen gas are separated by gas-liquid separation of the cathode electrolytic water. . The gas-liquid separator 430 has the same configuration as that of the gas-liquid separator 230 described above, that is, the separator main body 431, the separator main body 431, and the inlet 432 into which the electrolytic water flows, and the separator main body 431 is installed. And a liquid discharge port 433 for discharging the separated liquid and a gas discharge port 434 for discharging the separated gas. The gas-liquid separator 430 may include a cyclone gas-liquid separator.

The liquid outlet 433 may circulate and supply the sodium hydroxide solution connected to the circulation supply unit 480 to the anode chamber 410a and the cathode chamber 410b, respectively.

Here, the circulation supply unit 480 is branched from the circulation line 481 and the circulation line 481, respectively, and the first and second branch lines 482 and 483 connected to the anode chamber 410a and the cathode chamber 410b, respectively. ). The first branch line 482 may be connected to the first seawater supply line 421 or may be directly connected to the anode chamber 410a. In addition, the second branch line 483 may also be connected to the second seawater supply line 424, or may be directly connected to the cathode chamber 410b. In this case, it is preferable to adjust the circulation supply amount of the aqueous sodium hydroxide solution supplied to the cathode chamber 410b through the second branch line 483 so as to be 1 to 30% of the total circulation supply amount. In other words, when injected at 1% or less, it becomes a condition in which the cathode reduction effect caused by the injection of sodium hydroxide is not exerted, and when injected at 30% or more, excessive use of sodium hydroxide and chemicals of the diaphragm are applied. It is because it contains the problem which may weaken durability. As such, the supply amount of the sodium hydroxide solution circulated and supplied through the branch lines 482 and 483 may be controlled by setting different transfer capacities of the branch lines 482 and 483, and a separate three-way valve (not shown) is provided at the branch point. You can also adjust the amount of branching by installing.

On the other hand, a gas supply line 419 is connected to the gas outlet 434 of the gas-liquid separator 430, and the water removal unit 450 and the fuel cell 470 are sequentially installed in the gas supply line 419. Since the configuration and operation effects of the water removal unit 450 and the fuel cell 470 are the same as those described above with reference to FIGS. 1 to 3, detailed descriptions thereof will be omitted.

In addition, the seawater supplied to each of the anode chamber 410a and the cathode chamber 410b has the same concentration as that of the seawater supplied to the anode chamber 310a and the cathode chamber 31b of the diaphragm electrolyzer 311. To maintain the supply.

As described above, the seawater electrolytic and fuel cell composite systems 300 and 400 according to the third and fourth embodiments of the present invention are electrolyzed by using seawater electrolytic units 310 and 410 including the diaphragm electrolyzers 311 and 411. By classifying and discharging hydrogen gas and oxygen gas among the gases generated at the time, the high-purity hydrogen gas can be discharged without the hydrogen purifier from the gas supply line to produce power in the fuel cell.

In addition, some of the sodium hydroxide aqueous solution produced in the cathode chamber can be circulated supply only to the cathode chamber, or circulated supply to each of the cathode chamber and the anode chamber can be reused.

110. Seawater Electrolysis Unit
120. Sea water supply
130..Gas Separator
140..Sodium hypochlorite reservoir
150. Water removal unit
160..Gas Purifier
170. Fuel Cell

Claims (15)

A seawater electrolytic unit for electrolyzing the introduced seawater;
A seawater supply unit for supplying seawater to the seawater electrolysis unit;
A gas-liquid separator for separating the electrolyzed water electrolyzed in the seawater electrolytic unit into a liquid and a gas;
A sodium hypochlorite storage tank for storing the sodium hypochlorite solution separated by the gas-liquid separator;
A water removal unit for removing water contained in the gas component separated by the gas-liquid separator;
A gas purifier for purifying hydrogen gas of high purity from the gas from which water is removed from the water removing unit; And
And a fuel cell for producing electric power by using hydrogen gas supplied through the gas purifier. According to claim 1, The seawater electrolytic unit,
A membrane-free electrolytic cell having a seawater inlet and an electrolyzed water outlet, and having an anode and a cathode installed therein; And
And a power supply unit for supplying DC power to the anode and the cathode, respectively. A seawater electrolytic unit for electrolyzing the introduced seawater;
A seawater supply unit for supplying seawater to the seawater electrolysis unit;
A gas-liquid separator for separating the electrolyzed water electrolyzed in the seawater electrolytic unit into a liquid and a gas;
Sodium hypochlorite storage tank for storing the sodium hypochlorite solution generated in the seawater electrolysis unit;
A water removal unit for removing water contained in the gas component separated by the gas-liquid separator;
And a fuel cell for producing electric power by using hydrogen gas supplied through the gas-liquid separator. The method of claim 4, wherein the seawater electrolytic unit,
A diaphragm electrolyzer divided into an anode chamber and a cathode chamber by a diaphragm installed therein; And
And a power supply unit for supplying DC power to the anode chamber and the cathode chamber of the diaphragm electrolyzer.
And the anode chamber and the cathode chamber each have a seawater inlet and an electrolyzed water outlet. The method of claim 4, wherein
A cathode electrolytic water supply line connecting the electrolytic water outlet of the cathode chamber and the gas-liquid separator;
An anode electrolytic water discharge line connecting the electrolyte discharge port of the anode chamber and the sodium hypochlorite storage tank; And
A cathode electrolytic water supply line connecting the liquid outlet port of the gas-liquid separator and the anode electrolytic water discharge line to supply the separated liquid to the sodium hypochlorite storage tank; And
And a gas supply line connected to the gas outlet of the gas-liquid separator, wherein the water supply unit and the fuel cell are sequentially installed.
The method of claim 4, wherein
A cathode electrolytic water supply line connecting the electrolytic water outlet of the cathode chamber and the gas-liquid separator;
An anode electrolytic water discharge line connecting the electrolyte discharge port of the anode chamber and the sodium hypochlorite storage tank; And
A cathode electrolytic water supply line connecting the liquid outlet of the gas-liquid separator and the anode electrolytic water discharge line to supply the separated sodium bicarbonate solution to the sodium hypochlorite storage tank;
A gas supply line connected to a gas outlet of the gas-liquid separator, in which the water removal unit and the fuel cell are installed in sequence; And
And a circulation supply unit for circulating and supplying a part of the aqueous sodium hydrogen carbonate solution separated from the gas-liquid separator to the cathode chamber. The method of claim 6, wherein the sea water supply unit,
A first seawater supply line for supplying seawater to the anode chamber;
A first pump installed at the first sea water supply line;
A filter unit installed in the first sea water supply line;
A second seawater supply line for supplying seawater to the cathode chamber;
And a second pump installed at the second sea water supply line.
The second seawater supply line is connected to the circulation supply unit seawater electrolytic and fuel cell complex system. The method of claim 4, wherein
A cathode electrolytic water supply line connecting the electrolytic water outlet of the cathode chamber and the gas-liquid separator;
An anode electrolytic water discharge line connecting the electrolyte discharge port of the anode chamber and the sodium hypochlorite storage tank; And
A circulation supply unit configured to circulate and supply the aqueous sodium bicarbonate solution discharged from the liquid discharge port of the gas-liquid separator to each of the cathode chamber and the anode chamber; And
And a gas supply line connected to the gas outlet of the gas-liquid separator, wherein the water supply unit and the fuel cell are sequentially installed. 8. The combined seawater electrolyte and fuel cell system as recited in claim 7, wherein the seawater supplied to the cathode chamber through the second seawater supply line is a 1-10% sodium chloride solution. 10. The method of claim 1, wherein the water removal unit,
Seawater electrolysis and fuel cell complex system, characterized in that any one selected from the water removal filter, water removal absorbent, low temperature condensation unit. 10. The method according to any one of claims 1 to 9,
The fuel cell is a seawater electrolyte and fuel cell complex system, characterized in that the polymer electrolyte fuel cell. 10. The method according to any one of claims 1 to 9,
The generation concentration of the sodium hypochlorite solution is a seawater electrolyte and fuel cell composite system characterized in that it has a range of 500 ~ 6,000ppm. The gas-liquid separator according to any one of claims 1 to 9,
Seawater electrolytic and fuel cell composite system comprising a cyclone-type gas-liquid separator. The method according to any one of claims 4 to 8, wherein the diaphragm,
A seawater electrolytic and fuel cell complex system comprising an ion selective membrane or a diaphragm capable of moving a cation to a cathode and an anion to a cathode without an ion selective membrane. The seawater electrolyte and fuel according to any one of claims 6 to 8, wherein the aqueous sodium hydroxide solution supplied to the cathode chamber through the circulation supply unit is 1 to 30% of the total amount discharged from the gas-liquid separator. Battery composite system.

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