CN216808288U - Microbial fuel cell device for salt separation and desalination - Google Patents
Microbial fuel cell device for salt separation and desalination Download PDFInfo
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- CN216808288U CN216808288U CN202220538666.2U CN202220538666U CN216808288U CN 216808288 U CN216808288 U CN 216808288U CN 202220538666 U CN202220538666 U CN 202220538666U CN 216808288 U CN216808288 U CN 216808288U
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Abstract
The utility model relates to the technical field of fuel cells, in particular to a microbial fuel cell device for salt separation and desalination. The device comprises a reactor box body, wherein an anode chamber, a first desalting chamber, a first concentrating chamber, a second desalting chamber and a cathode chamber are sequentially arranged in the reactor box body; an anode electrode is arranged in the anode chamber, a cathode electrode is arranged in the cathode chamber, and the anode electrode is connected with the cathode electrode through a lead; a load resistor is arranged on the lead; anion exchange membranes are arranged between the anode chamber and the first desalting chamber and between the second concentrating chamber and the second desalting chamber; cation exchange membranes are arranged between the first desalting chamber and the first concentrating chamber and between the second desalting chamber and the cathode chamber; a nanofiltration membrane is arranged between the first concentration chamber and the second concentration chamber. The microbial fuel cell device provided by the utility model solves the problem of cell performance reduction caused by cation and anion enrichment in the anode chamber and the cathode chamber.
Description
Technical Field
The utility model relates to the technical field of fuel cells, in particular to a microbial fuel cell device for salt separation and desalination.
Background
The bioelectrochemical system is an electrochemical device which removes organic pollutants by oxidation using bacteria as a catalyst, converts chemical energy into electrical energy, and generates other useful products and provides special environmental functions. In recent years, the functions of the bioelectrochemical system are more and more diversified while the bioelectrochemical system is used for treating sewage. Researchers involved the combination of bioelectrochemical systems with electrolytic cell Technology to develop microbial electrolytic cells with the aid of which hydrogen can be produced (Environmental Science & Technology,2005,39(11): 4317-. The research personnel convert the carbon dioxide generated by the anode into organic biomass by using chlorella at the cathode, thereby realizing the fixation of carbon and forming a sustainable zero-carbon-rejection biological energy production and circulation system based on algae (Biosensors & Bioelectronics,2010,25(12): 2639-2643). Researchers have combined microbial electrolysis cells with seawater desalination processes to achieve dual efficiencies of hydrogen production and seawater desalination (Environmental Science & Technology,2010,44(24): 9578-.
The microbial desalting fuel cell features that the electrogenic bacteria in the anode chamber are degraded with organic substrate to produce electrons, which are conducted via the electrodes to the cathode electrode to contact with the electron acceptor to produce current to drive the negative and positive ions to pass through the negative and positive ion exchange membranes separately for desalting. If wastewater is used as an organic matter source, the microbial desalination cell can simultaneously achieve three goals: brine desalination, energy production and wastewater treatment are attractive environmental protection technologies.
Jacobson proposed an up-flow device to improve the efficiency of microbial desalination cell, which is generally cylindrical, wherein the cathode is an air cathode, and the anode chamber and desalination chamber are filled with water from bottom to top (Bioresource Technology,2011,102(1): 376-. Along with the continuous change of the reactor configuration and the cathode, the desalination efficiency of the microbial desalination fuel cell is improved to a certain extent, and the microbial desalination fuel cell can become an independent seawater desalination/high-salinity wastewater treatment process. Particularly, the microbial desalination fuel cell can be used as a pretreatment means of a high-salt water concentration process so as to reduce the high load of salt or dissolved solids in the existing system and reduce energy consumption. However, the microbial desalination fuel cell has some problems, most typically, the electricity generation performance is unstable, and one of the main factors influencing the electricity generation performance is that a large amount of chloride ions enter the anode chamber during the desalination process, the pH changes greatly, so that the activity of the electricity generation bacteria in the anode chamber is greatly influenced, and the electricity generation capacity is reduced.
Chinese patent document CN103482728A discloses a desalination technology using a microbial fuel cell to drive capacitive deionization, in which a microbial fuel cell processes wastewater to convert chemical energy into electrical energy and then applies the generated voltage to a separate capacitive deionization device to process an ion-containing solution, which is actually a coupling of the two devices, thereby avoiding accumulation of anions and cations in the anode and cathode chambers. Chinese patent document CN107892396A discloses a microbial desalination apparatus using a capacitive deionization electrode instead of an ion exchange membrane, in which activated carbon fibers are bonded to the surface of a titanium collector, and ions migrate and are adsorbed onto the activated carbon fibers, thereby reducing the influence on the anode-producing microorganisms. Chinese patent document CN102263278A discloses a continuous flow microbial fuel cell and a cell stack, in which wastewater is circulated between an anode chamber and a cathode chamber of a single cell through a pipeline, so as to effectively neutralize proton hydrogen generated in the anode chamber and hydroxyl negative ions generated in the cathode chamber, thereby avoiding adverse effects on microbial growth and metabolism, and the anode chambers and the cathode chambers of different cell units are communicated with each other for the cell stack. In this device, the anolyte and catholyte are circulated in communication.
In the microbial desalination fuel cell reactor, a large amount of chloride ions enter the anode chamber to be accumulated continuously in the desalination process, the pH value between the cathode chamber and the anode chamber is unbalanced, the growth and metabolism of anode microorganisms are inhibited, the activity of anode electrogenic bacteria is reduced and even the anode electrogenic bacteria die, and the performance of the anode is reduced rapidly. The existing microbial fuel cell cannot solve the problem of performance reduction of a reactor caused by cation enrichment of an anode chamber and a cathode chamber of the reactor.
Further, the "environmental admission condition" issued by the environmental protection department in 2015 stipulates: the salt mud which is generated by the wastewater treatment and cannot be recycled is temporarily managed according to the dangerous waste, so the treatment cost of the miscellaneous salt is very high, the economic pressure is increased, and the rigid landfill effect of the dangerous waste is difficult to completely ensure. Under the current situation of relative lack of water resources, a process for reducing emission of industrial wastewater and recycling miscellaneous salt is found, and the process has economic and environmental strategic meanings. At present, the common salt separation technology for desulfurization wastewater is generally used for removing most organic matters and heavy metals in brine through pretreatment, and then Na is separated through a membrane method, a thermal method and a cold method2SO4And NaCl fractional crystallization. In addition, the crystallizer of Wiriana may be provided with a washing leg (salt leg) to separate CaSO depending on the grain characteristics4、CaF2、Mg(OH)2And simultaneously separating and purifying the salt. However, these devices are expensive and technically difficult.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a microbial fuel cell device for salt separation and desalination, which can simultaneously separate monovalent ions and divalent ions in the process of desalting desulfurization wastewater and can solve the problem of cell performance reduction caused by enrichment of anions and cations in an anode chamber and a cathode chamber.
The utility model provides a microbial fuel cell device for salt separation and desalination, which comprises a reactor box body, wherein an anode chamber, a first desalination chamber, a first concentration chamber, a second desalination chamber and a cathode chamber are sequentially arranged in the reactor box body;
an anode electrode is arranged in the anode chamber, a cathode electrode is arranged in the cathode chamber, and the anode electrode is connected with the cathode electrode through a lead; a load resistor is arranged on the lead;
anion exchange membranes are arranged between the anode chamber and the first desalting chamber and between the second concentrating chamber and the second desalting chamber;
cation exchange membranes are arranged between the first desalting chamber and the first concentrating chamber and between the second desalting chamber and the cathode chamber;
a nanofiltration membrane is arranged between the first concentration chamber and the second concentration chamber.
Further, the cathode electrode adopts an air cathode.
Further, a platinum carbon catalyst is arranged on the side wall of the air cathode, which is in contact with the solution, and a tetrafluoroethylene waterproof layer is arranged on the side wall of the air cathode, which is in contact with the air.
Further, the anode electrode adopts a carbon fiber brush.
Furthermore, the nanofiltration membrane adopts an electrostatic spinning nanofiber membrane.
Further, the anode chamber, the first desalting chamber, the first concentrating chamber, the second desalting chamber and the cathode chamber are all provided with a water inlet and a water outlet.
Furthermore, the water outlet of the first desalting chamber is connected with the water inlet of the second desalting chamber through a pipeline.
Further, be equipped with a plurality of re-separation process chamber between the second desalination room with the cathode chamber, the re-separation process chamber includes two concentrate room and a desalination room that connect gradually.
Furthermore, a nanofiltration membrane is arranged between the two concentration chambers.
Further, an anion exchange membrane is arranged between the concentration chamber and the desalting chamber.
Compared with the prior art, the utility model has the following advantages:
(1) according to the microbial fuel cell device for salt separation and desalination, provided by the utility model, the plurality of concentrating chambers and desalting chambers are arranged between the anode chamber and the cathode chamber, and the ion pairs of each structural unit can be separated through single electron transfer on the electrodes, so that the charge transfer efficiency and the desalination efficiency are improved.
(2) The utility modelCompared with the traditional microbial desalination fuel cell structure, the microbial fuel cell device for salt separation and desalination has the advantages that the anions in the additionally arranged second desalination chamber sequentially enter the first concentration chamber and the second concentration chamber, the accumulation of the anions in the anode chamber cannot be increased, and the cations in the first desalination chamber also enter the first concentration chamber and the second concentration chamber but do not enter the cathode chamber; na in desulfurization waste water2SO4And NaCl are enriched in the second concentration chamber and the first concentration chamber respectively, so that separation is realized; the problem of the cell performance reduction caused by the enrichment of anions and cations in the anode chamber and the cathode chamber is solved.
(2) The microbial fuel cell device for salt separation and desalination provided by the utility model can allow a larger number of structural units to be added by optimizing the distance between membranes, thereby obviously improving the system processing capacity.
(3) The microbial fuel cell device for salt separation and desalination provided by the utility model has low energy consumption, can realize salt separation and desalination of desulfurization wastewater without external voltage, and can reduce the high load of salt or dissolved solids in a system and reduce energy consumption as a pretreatment process of a zero-discharge integral process; the operation condition is mild, the microbial fuel cell works in the environment of normal temperature, normal pressure and near neutrality, the maintenance cost of the reactor is low, and the safety is strong.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a schematic view showing the structure of a microbial fuel cell device for salt separation and desalination in example 1 of the present invention;
FIG. 2 is a schematic view showing the structure of a re-separation chamber in example 2 of the present invention;
FIG. 3 is a schematic structural view of a microbial fuel cell device for salt separation and desalination in example 2 of the present invention.
Description of reference numerals: 1-reactor box body, 2-anode chamber, 201-anode electrode, 3-first desalting chamber, 4-first concentrating chamber, 5-second concentrating chamber, 6-second desalting chamber, 7-cathode chamber, 701-cathode electrode, 8-first anion exchange membrane, 9-second anion exchange membrane, 10-first cation exchange membrane, 11-second cation exchange membrane, 12-first nanofiltration membrane, 13-lead, 14-load resistor, 15-re-separation treatment chamber, 1501-third concentrating chamber, 1502-fourth concentrating chamber, 1503-third desalting chamber, 1504-second nanofiltration membrane, 1505-third anion exchange membrane and 16-fourth anion exchange membrane.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise. Furthermore, the terms "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Example 1
A microbial fuel cell device for salt separation and desalination, as shown in figure 1.
An anode chamber 2, a first desalting chamber 3, a first concentrating chamber 4, a second concentrating chamber 5, a second desalting chamber 6 and a cathode chamber 7 are sequentially arranged in the reactor box body 1 from left to right. The anode chamber 2, the first desalting chamber 3, the first concentrating chamber 4, the second concentrating chamber 5, the second desalting chamber 6 and the cathode chamber 7 are all provided with a water inlet and a water outlet.
The anode electrode 201 is arranged in the anode chamber 2, the anode electrode 201 in the embodiment adopts a carbon fiber brush, is processed by carbon fiber and titanium wire, is soaked overnight by acetone before use to remove oil stain, is cleaned by distilled water and is subjected to heat treatment at 450 ℃ for 30 minutes; the carbon fiber brush is attached with an electrogenesis bacteria biomembrane with stable activity in an inoculation operation mode (the principle is the same as that of microbial membrane acquisition by an anode electrode in the existing microbial fuel cell).
The cathode electrode 701 is installed in the cathode chamber 7, and the cathode electrode 701 in this embodiment is an air cathode, and the surface of the air cathode in contact with the solution is coated with a bonded platinum carbon catalyst, and the surface in contact with the air is coated with a polytetrafluoroethylene waterproof layer.
The anode 201 and the cathode 701 are connected by a lead 13, and a load resistor 14 is attached to the lead 13 between the anode 201 and the cathode 701.
A first anion exchange membrane 8 is arranged between the anode chamber 2 and the first desalting chamber 3, and a second anion exchange membrane 9 is arranged between the second concentrating chamber 5 and the second desalting chamber 6; a first cation exchange membrane 10 is arranged between the first desalting chamber 3 and the first concentrating chamber 4, and a second cation exchange membrane 11 is arranged between the second desalting chamber 6 and the cathode chamber 7; a first nanofiltration membrane 12 is installed between the first concentration chamber 4 and the second concentration chamber 5, and the first nanofiltration membrane 12 in the embodiment adopts an electrostatic spinning nanofiber membrane.
In the operation process, anions in the second desalting chamber 6 pass through a second anion exchange membrane 9, divalent anions are intercepted and enriched in the second concentrating chamber 5 through a first nanofiltration membrane 12, and monovalent anions are enriched in the first concentrating chamber 4 through the first nanofiltration membrane 12; the cations in the first desalting chamber 3 are enriched in the first concentrating chamber 4 and the second concentrating chamber 5 through the first cation exchange membrane 10. Compared with the traditional three-chamber structure of the microbial desalination fuel cell (only provided with an anode chamber, a desalination chamber and a cathode chamber), the anions in the second desalination chamber 6 are added into the first concentration chamber 4 and the second concentration chamber 5, so that the accumulation of the anions in the anode chamber 2 is not increased, and the cations in the first desalination chamber 3 are also added into the first concentration chamber 4 and the second concentration chamber 5, but not into the cathode chamber 7. Na in desulfurization waste water2SO4And NaCl are enriched in the second concentration chamber 5 and the first concentration chamber 4 respectively, so that the separation purpose is achieved.
The water inlet of the first desalting chamber 3 is used for feeding the salt water, the water outlet of the first desalting chamber 3 is used for discharging the desalted water, the desalted water can be combined, and the discharged water of the first desalting chamber 3 can be used as the water inlet of the second desalting chamber 6 for desalting step by step. The delivery port of the first desalination chamber 3 that this embodiment provided is connected with the water inlet of the second desalination chamber 6 through plastic conduit to maintain the water transmission balance that takes place because the nanometer clearance transmission of nanofiltration membrane in first desalination chamber 3 and the second desalination chamber 6.
Example 2
A microbial fuel cell device for salt separation and desalination, as shown in fig. 3, the technical solution thereof is substantially the same as that of example 1 except that: a re-separation treatment chamber 15 is provided between the second desalination chamber 6 and the cathode chamber 7. The re-separation treatment chamber 15 is composed of two concentration chambers and a desalination chamber which are connected in sequence, a nanofiltration membrane is arranged between the two concentration chambers, and an anion exchange membrane is arranged between the concentration chambers and the desalination chamber. An anion filtering membrane is arranged between the re-separation treatment chamber 15 and the second desalting chamber 6, and a cation exchange membrane is arranged between the re-separation treatment chamber 15 and the cathode chamber 7.
As shown in fig. 2, the re-separation chamber 15 in this embodiment is composed of a third concentration chamber 1501, a fourth concentration chamber 1502, and a third desalination chamber 1503 in this order from left to right. A second nanofiltration membrane 1504 is installed between the third concentration chamber 1501 and the fourth concentration chamber 1502, and a third anion exchange membrane 1505 is installed between the fourth concentration chamber 1502 and the third desalination chamber 1503. A fourth anion exchange membrane 16 is arranged between the third concentration chamber 1501 and the second desalination chamber 6. A second cation exchange membrane 11 is installed between the third concentrating compartment 1501 and the cathode compartment 7.
Fig. 2 and 3 in this embodiment are enclosed by rectangular frames for clarity of the structure of the re-separating process chamber, and the rectangular frames are not practical.
In the microbial fuel cell device of this embodiment, a plurality of the above-described re-separation treatment chambers may be provided between the second concentrating chamber and the cathode chamber, and an anion exchange membrane is provided between two adjacent re-separation treatment chambers to increase the treatment efficiency. By optimizing the inter-membrane distance, a greater number of building blocks (re-separating process chambers) can be allowed to be added, significantly increasing the system throughput.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the utility model has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (10)
1. The microbial fuel cell device for salt separation and desalination is characterized by comprising a reactor box body, wherein an anode chamber, a first desalination chamber, a first concentration chamber, a second desalination chamber and a cathode chamber are sequentially arranged in the reactor box body;
an anode electrode is arranged in the anode chamber, a cathode electrode is arranged in the cathode chamber, and the anode electrode is connected with the cathode electrode through a lead; a load resistor is arranged on the lead;
anion exchange membranes are arranged between the anode chamber and the first desalting chamber and between the second concentrating chamber and the second desalting chamber;
cation exchange membranes are arranged between the first desalting chamber and the first concentrating chamber and between the second desalting chamber and the cathode chamber;
a nanofiltration membrane is arranged between the first concentration chamber and the second concentration chamber.
2. The microbial fuel cell device for salt separation and desalination according to claim 1, wherein the cathode electrode is an air cathode.
3. The microbial fuel cell device for salt separation and desalination of claim 2, wherein the side wall of the air cathode in contact with the solution is provided with a platinum-carbon catalyst, and the side wall of the air cathode in contact with the air is provided with a tetrafluoroethylene waterproof layer.
4. The microbial fuel cell device for salt separation and desalination of claim 1, wherein the anode electrode is a carbon fiber brush.
5. The microbial fuel cell device for salt separation and desalination of claim 1, wherein the nanofiltration membrane is an electrospun nanofiber membrane.
6. The microbial fuel cell device for salt separation and desalination according to claim 1, wherein the anode chamber, the first desalination chamber, the first concentration chamber, the second desalination chamber, and the cathode chamber are each provided with a water inlet and a water outlet.
7. The microbial fuel cell device for salt separation and desalination of claim 1, wherein the water outlet of the first desalination chamber is connected with the water inlet of the second desalination chamber through a pipeline.
8. The microbial fuel cell device for salt separation and desalination of claim 1, wherein a plurality of re-separation treatment chambers are provided between the second desalting chamber and the cathode chamber, and the re-separation treatment chambers comprise two concentrating chambers and one desalting chamber which are connected in sequence.
9. The microbial fuel cell device for salt separation and desalination of claim 8, wherein a nanofiltration membrane is arranged between the two concentration chambers.
10. The microbial fuel cell device for salt separation and desalination of claim 8, wherein an anion exchange membrane is arranged between the concentration chamber and the desalination chamber.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202220538666.2U CN216808288U (en) | 2022-03-11 | 2022-03-11 | Microbial fuel cell device for salt separation and desalination |
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| CN202220538666.2U CN216808288U (en) | 2022-03-11 | 2022-03-11 | Microbial fuel cell device for salt separation and desalination |
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| CN216808288U true CN216808288U (en) | 2022-06-24 |
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