CN108128899A - A kind of EGSB-MFC coupled systems and its biodegrading process for being used to handle coking wastewater difficult to degrade - Google Patents

Abstract

The invention belongs to the technical field of energy and sewage treatment. In order to solve the problem that organic matter and ammonia nitrogen cannot be treated up to the standard at the same time due to the inhibitory effect of toxic substances on denitrification bacteria in EGSB reactors in the treatment of coking wastewater, a method for treating difficult wastewater is provided. The EGSB‑MFC coupling system for degrading coking wastewater and its degradation method, the reaction zone of the EGSB anaerobic reactor is the anode chamber of the coupling system, the backflow area is set as the cathode chamber of the coupling system, and the cathode and anode chambers are connected by a cation exchange membrane Tube connection; the cathode and anode chambers are provided with conductive electrodes, and the cathode and anode conductive electrodes are connected to external resistors; the bottom of the anode chamber is connected to the water inlet tank through a porous water distribution plate, the top of the anode chamber is provided with a water outlet, and the water outlet is connected to the top of the cathode chamber; the bottom of the cathode chamber is connected to the top of the cathode chamber. The connecting pipe is connected to the bottom of the anode chamber. The structure is simple and the performance is optimized. It can simultaneously remove organic matter and nitrogen-containing compounds in coking wastewater, realize the full degradation of coking wastewater, and can generate electricity and recover energy.

Description

An EGSB-MFC coupling system for treating refractory coking wastewater and its degradation method

technical field

The invention belongs to the technical field of energy and sewage treatment, and in particular relates to an EGSB-MFC coupling system for treating refractory coking wastewater and a degradation method thereof.

Background technique

Coking wastewater is a typical refractory organic wastewater containing aromatic compounds such as polycyclic aromatic hydrocarbons. Its large-scale discharge causes serious water pollution and directly threatens human health. Therefore, the treatment of coking wastewater has become an important issue in the field of wastewater treatment. Important tasks and puzzles. In addition to pretreatment, coking wastewater treatment methods are still dominated by biological methods, such as traditional A/O, A ² /O and their improved processes. The main problems of these methods are: (1) The sludge concentration is low, The ability to resist impact load is weak; (2) The processing energy consumption is high. At present, the contradiction between energy supply and demand is prominent, and energy shortage has become a common problem faced by all countries in the world. Therefore, in the face of the dual pressure of refractory industrial wastewater pollution and energy shortage, the traditional high-energy-consuming wastewater treatment technology has been difficult to meet the requirements of sustainable development. It has become an inevitable requirement and development trend in the field of wastewater treatment to realize the recycling of wastewater and develop new industrial wastewater biological treatment technologies with high efficiency and low consumption.

Expanded Granular Sludge Bed (EGSB) is a third-generation anaerobic reactor. It has the advantages of high concentration and high activity of granular sludge, high effluent reflux, large rising flow rate, and strong impact load resistance. It is used in various difficult-to-treat Good results have been achieved in wastewater. However, for most EGSB reactors in industrial wastewater treatment, more research is on the removal of organic matter. The removal of ammonia nitrogen is inhibited due to the toxicity of wastewater and the growth of denitrifying and nitrifying bacteria affected by anaerobic conditions. Therefore, the EGSB reaction In the treatment of industrial wastewater, especially the treatment of coking wastewater, there is a defect that COD and ammonia nitrogen cannot be removed at the same time.

Microbial Fuel Cells (MFC) is a device that uses microorganisms as biocatalysts to convert chemical energy in sewage into electrical energy. It can not only remove pollutants in water, but also recycle electrical energy. It is a clean Efficient water treatment technologies have been extensively developed in recent years due to their innovation and environmental benefits. The document "Simultaneous nitrification, denitrification and carbon removal in microbial fuel cells" (Bernardino Virdis, Water Research 44 (2010) 2970-2980) reported for the first time that biocathode synchronous nitrification and denitrification MFC denitrification produces electricity, and the anode culture solution contains carbon (CH ₃ COONa) and ammonia nitrogen (NH ₄ Cl), the organic matter is oxidized and degraded under the action of electrochemical microorganisms at the anode, and the electrons generated are transferred to the anode electrode, and further transferred to the cathode electrode through an external circuit; the anode effluent directly enters the cathode for denitrification ; In the cathode chamber, NH ₄ ⁺ -N is aerobically converted into NO ₃ ^- or NO ₂ ^- , and then the electrons transferred from the anode are used for electrochemical denitrification and denitrification (NO ₃ ^- +e ^- → N ₂ ). The concentrations of NO ₃ ^- -N and NH ₄ ⁺ -N in the cathode effluent water are as low as 1.0mg/L and 2.13mg/L, the TN removal rate is as high as 94.1%, the output current is 13.35mA, and the power is 0.89mW. This method overcomes the shortcomings of traditional biological denitrification, such as the independent space of nitrification and denitrification, the generation of a large amount of denitrification sludge, and the treatment of low COD/N wastewater. However, the simulated wastewater used in this study is easily degradable wastewater. For the refractory coking wastewater, it will inhibit the activity of microorganisms and greatly affect the material degradation and electricity generation performance of MFC. Some researchers add some easily degradable organic matter to carry out the co-metabolism of refractory substances and alleviate the inhibitory effect of toxic substances on microorganisms, but it brings about a large amount of sludge production, increasing the cost of subsequent sludge treatment and the purchase of easily degradable substances fee. Therefore, using MFC alone to treat refractory coking wastewater has defects such as material degradation and poor electricity production.

In summary, the development of a new type of MFC that can treat refractory industrial wastewater and recover the chemical energy in it is promising. It is not only in line with my country's environmental protection policy for energy conservation and emission reduction, but also in line with the development trend of wastewater treatment technology. There are relatively few reports on the EGSB-MFC coupled MFC for treating refractory wastewater coking wastewater and generating electricity.

The application number is 201510901172.0, and the name of the invention is pretreatment-EGSB-microbial electrochemical combined excess sludge degradation device and method. This patent discloses a pretreatment-EGSB-microbial electrochemical combined excess sludge degradation device and method. The invention belongs to the technical field of surplus sludge resource utilization and reduction. In this method, the pretreated sludge is degraded by the anaerobic granular sludge of the EGSB anaerobic processor, and finally further degraded by microbial electrochemistry. However, this invention mainly uses the advantages of anaerobic EGSB to treat high-concentration wastewater to treat the organic matter in the excess sludge. The organic matter components are different from those in the coking wastewater. Most of the coking wastewater is composed of toxic substances such as phenol and aromatic compounds. Mainly, the joint MFC is also mainly for the advanced treatment of the remaining organic matter after EGSB treatment, and does not involve the treatment of nitrogen-containing compounds, resulting in the possibility that the effluent nitrogen discharge may not meet the standard. In addition, the invention is a joint use of EGSB and MFC rather than coupling, and the two independently perform their respective functions to achieve pollutant removal.

Contents of the invention

The present invention provides an EGSB-MFC for treating refractory coking wastewater in order to solve the problem that organic matter and ammonia nitrogen cannot be treated up to the standard due to the inhibitory effect of toxic substances on denitrification bacteria in the EGSB reactor. The coupling system and its degradation method effectively utilize the wastewater treatment advantages of EGSB and MFC, with simple structure and optimized performance, which can simultaneously remove organic matter and nitrogen-containing compounds in coking wastewater, and achieve full degradation of coking wastewater.

The present invention is realized by the following technical solutions: an EGSB-MFC coupling system for treating refractory coking wastewater, comprising an EGSB reactor with a gas collector at the top, an MFC system coupled with the EGSB reactor, and the EGSB reactor The reaction zone is set as the anode chamber of the EGSB-MFC coupling system, the reflux zone of the EGSB reactor is set as the cathode chamber of the EGSB-MFC coupling system, and the anode chamber and the cathode chamber are connected by a connecting pipe provided with a cation exchange membrane. ; The anode chamber and the cathode chamber are provided with conductive electrodes, and the anode conductive electrode and the cathode conductive electrode are connected to an external resistor; the bottom of the anode chamber is connected to the water inlet tank through a porous water distribution plate, and the water inlet pump is connected between the water inlet tank and the anode chamber. Water outlet I is arranged on the top of the anode chamber, and the water outlet I is connected to the top of the cathode chamber, and the side wall of the top section of the cathode chamber is provided with water outlet II; the bottom of the cathode chamber is connected to the bottom of the anode chamber through a connecting pipe.

The conductive electrodes in the anode chamber and the cathode chamber are graphite felts, and the anode conductive electrodes are filled with activated carbon layers attached to microorganisms; activated carbon layers attached to denitrification bacteria are arranged on both sides of the cathode conductive electrodes, and an aeration device is arranged at the bottom of the activated carbon attached to denitrification bacteria. Top wire connection. A plurality of sampling ports are arranged at intervals on the side wall of the anode chamber. The water inlet tank is a high water inlet tank, and the water inlet tank is higher than the top of the anode chamber.

The filling height of the activated carbon layer with microorganisms attached is 1/3 of the height of the anode chamber, and the activated carbon is fine columnar granular activated carbon with a particle diameter of 1.5-2 mm. Anaerobic activated sludge is also arranged in the anode chamber, and anaerobic active The volume of the sludge is 1/3 of the volume of the anode chamber, and the activated carbon attached to the denitrification bacteria is a fine columnar granular activated carbon with a particle diameter of 1.5-2mm, and the filling height is 1/4 of the height of the cathode chamber. It is equipped with high-efficiency denitrification sludge to realize synchronous nitrification and denitrification, and the volume is 1/3 of the volume of the cathode chamber.

The volume ratio of the anode chamber to the cathode chamber is 1:10; the height-to-diameter ratio of the reaction zone of the EGSB reactor is 12:1, and the height-to-diameter ratio of the reflux zone is 1:1.

A method for degrading coking wastewater using the EGSB-MFC coupling system for treating refractory coking wastewater, using the granular sludge reaction zone of the EGSB reactor as the anode zone of the coupling system, and the recirculation zone as the cathode zone and anode zone of the coupling system It is connected to the cathode area through a cation exchange membrane. Under the anaerobic environment of the EGSB anode area, the organic matter in the coking wastewater is decomposed by electrogenic bacteria to generate electrons and protons, which are transferred to the cathode return area through the external resistance; the return area is highly efficient Denitrification bacteria use the electrons transferred from the anode as electron donors to perform simultaneous nitrification and denitrification denitrification.

Specific steps are as follows:

(1) Start-up of the EGSB reactor: Inoculate anaerobic sludge and activated carbon particles, start the EGSB anaerobic reactor anaerobically with domestic sewage, and form black anaerobic granular sludge; then domestic sewage and coking wastewater are mixed in a ratio of 2:1, 1 :1, 1:2, 1:5, 0:1 ratios for acclimatization in sequence, taking COD and gas production in the gas collection device as the control index, COD removal reaches 80~90% in each stage, and there is obvious gas production until;

(2) Screening and domestication of highly efficient denitrification bacteria: inoculate activated sludge and activated carbon particles, use nitrogen-containing wastewater with an ammonia nitrogen concentration of 80-100mg/L and a COD concentration of 2000-3500mg/L to screen for denitrification bacteria, aerobic Under certain conditions, until the removal effect of ammonia nitrogen and total nitrogen reaches more than 90%; then carry out nitrogen-containing wastewater and coking wastewater according to the ratio of 2:1, 1:1, 1:2, 1:5, 0:1 in sequence To domesticate denitrification bacteria, the removal of ammonia nitrogen and total nitrogen is used as the control index, and the removal effect of each stage reaches 90% and 70% respectively;

(3) Start-up and operation of the EGSB-MFC coupling system: Connect the high-efficiency denitrification bacteria (including activated carbon particles) screened above into the reflow area, connect the cathode and anode conductive electrodes, and externally connect R=1000Ω resistors, and use 100% coking wastewater for coupling system start up;

(4) EGSB-MFC coupling: Coking wastewater is pumped into the water inlet through the inlet pump. Under the anaerobic environment of the EGSB anode area, the electrogenic bacteria decompose the organic matter in the coking wastewater to generate electrons and protons, which are transferred to the cathode return area through the external resistance ; The high-efficiency denitrification bacteria in the reflux area use the electrons transferred from the anode as electron donors to perform simultaneous nitrification and denitrification denitrification; the water inflow is controlled at 0.8L/h, the reflux ratio is 12.5~15, and the rising flow rate is 1.38~1.63m/h ; Aeration in the recirculation zone maintains DO at 0.3~0.5mg/L.

Compared with a single system, the EGSB-MFC coupling system of the present invention has more advantages in the treatment of coking wastewater. It not only overcomes the problem of inhibition of toxic substances on denitrification bacteria, but also solves the problem of EGSB reactor When dealing with coking wastewater, the ammonia nitrogen treatment is not up to standard, and finally achieves the purpose of synchronous carbon and nitrogen removal, and can generate electricity and recover energy. The present invention treats coking wastewater with a COD concentration of 1000-2000mg/L and an ammonia nitrogen concentration of 50-200mg/L. The COD removal process is mainly completed in the reaction zone of the EGSB reactor, and the removal rate is 80-90%. Between; in the return area of the EGSB reactor, micro-aeration promotes the transformation of ammonia nitrogen by denitrification bacteria, and at the same time, the electrons generated during COD removal are used to transfer to the cathode return area through an external circuit, and the electrode electrons are used as electron donors for denitrification. The removal rate of ammonia nitrogen and total nitrogen can reach 80~90% and 70~80%.

The EGSB reactor in the coupling system of the present invention can degrade the toxic organic matter in the coking wastewater and alleviate its inhibitory effect on denitrification bacteria. At the same time, the MFC coupling can apply the electrons generated by the degradation of organic matter to the denitrification process in the subsequent reflux zone of EGSB. It provides the possibility for the degradation of coking wastewater.

The present invention adopts the novel coupling system that the EGSB reactor reaction zone is the anode chamber of MFC, and the EGSB reactor reflux chamber is the cathode chamber of MFC to process the coking wastewater. Sludge from the nitrification tank of the sewage treatment plant not only utilizes the advantages of the EGSB reactor in the treatment of refractory industrial wastewater organic matter, but also utilizes the electrons generated by the degradation of organic matter at the anode of the MFC for cathode denitrification, which not only solves the current problem of refractory coking wastewater Synchronous removal of carbon and nitrogen is difficult, and part of the energy can be recycled to realize the resource utilization of wastewater.

Description of drawings

Fig. 1 is a schematic structural diagram of the EGSB-MFC coupling system for treating refractory coking wastewater according to the present invention.

In the figure: 1-gas collector; 2-EGSB reactor; 2.1-anode chamber; 2.2-cathode chamber; 2.3-cation exchange membrane; 2.4-conductive electrode; 2.5-water outlet I; 2.6-water outlet II; 3- MFC system; 4-external resistance; 5-porous water distribution plate; 6-water inlet tank; 7-water inlet pump; 8-activated carbon layer attached to microorganisms; 9-activated carbon layer attached to denitrification bacteria;

Detailed ways

The technical solution in the present invention will be clearly and completely described below in conjunction with the embodiments and the accompanying drawings. The following examples are only used to illustrate the technical solution of the present invention more clearly, but not to limit the protection scope of the present invention.

An EGSB-MFC coupled system for treating refractory coking wastewater, comprising an EGSB reactor 2 with a gas collector 1 arranged on the top, an MFC system 3 coupled with the EGSB reactor 2, and a reaction zone of the EGSB reactor 2 Set as the anode chamber 2.1 of the EGSB-MFC coupling system, the reflow zone of the EGSB reactor is set as the cathode chamber 2.2 of the EGSB-MFC coupling system, and the connection between the anode chamber 2.1 and the cathode chamber 2.2 is provided with a cation exchange membrane 2.3 tube connection; the anode chamber 2.1 and the cathode chamber 2.2 are provided with a conductive electrode 2.4, and the anode conductive electrode and the cathode conductive electrode are connected to an external resistor 4; the bottom of the anode chamber 2.1 is connected to the water inlet tank 6 through a porous water distribution plate 5, and the water inlet Water inlet pump 7 is connected between water tank 6 and anode chamber 2.1, and water outlet I 2.5 is arranged on the top of anode chamber 2.1, and water outlet I 2.5 is connected with the top of cathode chamber 2.2, and the side wall of cathode chamber 2.2 top section is provided with water outlet II 2.6; The bottom of the cathode chamber 2.2 is connected to the bottom of the anode chamber 2.1 through a communication pipe.

The conductive electrodes in the anode chamber and the cathode chamber are made of graphite felt, and the surroundings of the anode conductive electrodes are filled with activated carbon layers 8 attached to microorganisms; activated carbon layers 9 attached to denitrification bacteria are arranged on both sides of the cathode conductive electrodes, and an aeration device 10 is arranged at the bottom of the activated carbon attached to denitrification bacteria , top wire connection. A number of sampling ports 2.6 are arranged at intervals on the side wall of the anode chamber. The water inlet tank is a high-level water inlet tank, and the water inlet tank is higher than the top of the anode chamber.

The MFC system is placed in the EGSB reactor, the granular sludge reaction area of the EGSB reactor is the anode area of the coupling system, and the recirculation area is the cathode area of the coupling system. There are multiple water outlets in the anode area and the cathode area; the filling height of the activated carbon layer with microorganisms attached is 1/3 of the height of the anode chamber, and the activated carbon is fine columnar granular activated carbon with a particle size of 1.5-2mm. Anaerobic activated sludge is provided, and the volume of anaerobic activated sludge is 1/3 of the volume of the anode chamber.

Activated carbon has strong adsorption performance, which is convenient for the attachment of microorganisms. At the same time, it has conductivity, which is beneficial to the transfer of electrons in the electrochemical system. The particle size of the activated carbon is 1.5~2mm, and the filling height is 1/3 of the height of the reactor; graphite carbon The felt is a conductive electrode. Before the reactor is started, the anaerobic activated sludge is used as the inoculation sludge, and the inoculation amount is 2/3 of the volume of the reaction zone of the reactor (including the volume of activated carbon). The anode area is in an anaerobic environment. Under anaerobic conditions, the electrogenic bacteria decompose the organic matter in the wastewater to produce electrons and protons. The electrons are transmitted to the cathode electrode through the external circuit for the cathode denitrification; the protons enter the cathode chamber through the cation exchange membrane. , combined with oxygen to form water.

The cathode area of the system is filled with fine columnar granular activated carbon. Activated carbon has strong adsorption performance, which is convenient for the attachment of microorganisms. At the same time, it has conductivity, which is conducive to the transfer of electrons in the electrochemical system. The diameter is 1.5-2mm, and the filling height is 1/4 of the height of the cathode chamber. The cathode chamber is also equipped with high-efficiency denitrification sludge, and the volume is 1/3 of the volume of the cathode chamber. The particle size of the activated carbon is 1.5~2mm, the filling height is 1/4 of the height of the reflow zone, and the graphite carbon felt is a conductive electrode. 1/3 of the volume of the recirculation zone. The cathode area is in a state of micro-oxygen, and ammonia nitrogen is removed in this area through the simultaneous nitrification and denitrification of efficient denitrification bacteria with the cathode electrode as the electron donor. The volume ratio of the anode chamber to the cathode chamber is 1:10; the height-to-diameter ratio of the reaction zone of the EGSB reactor is 12:1, and the height-to-diameter ratio of the reflux zone is 1:1.

The method for degrading coking wastewater by using the above-mentioned EGSB-MFC coupling system for treating refractory coking wastewater, using the granular sludge reaction zone of the EGSB reactor as the anode zone of the coupling system, and the recirculation zone as the cathode zone of the coupling system, the anode zone and the cathode The areas are imperviously connected by cation exchange membranes. Under the anaerobic environment of the EGSB anode area, the electrogenic bacteria decompose the organic matter in the coking wastewater to generate electrons and protons, which are transferred to the cathode return area through the external resistance; the return area efficiently denitrifies The bacteria use the electrons transferred from the anode as electron donors to carry out simultaneous nitrification and denitrification denitrification.

The specific steps are:

(1) Start-up of the EGSB reactor: Inoculate anaerobic sludge and activated carbon particles, start the EGSB anaerobic reactor anaerobically with domestic sewage, and form black anaerobic granular sludge; The ratio of :1, 1:2, 1:5, 0:1 is domesticated in sequence, with the removal of COD as the control index, and the removal of COD in each stage reaches 80%~90%;

(2) Screening and domestication of highly efficient denitrification bacteria: inoculate activated sludge and activated carbon particles, use nitrogen-containing wastewater with an ammonia nitrogen concentration of 80-100mg/L and a COD concentration of 2000-3500mg/L to screen for denitrification bacteria, aerobic Under certain conditions, until the removal effect of ammonia nitrogen and total nitrogen reaches more than 90%; then carry out nitrogen-containing wastewater and coking wastewater according to the ratio of 2:1, 1:1, 1:2, 1:5, 0:1 in sequence To domesticate denitrification bacteria, the removal of ammonia nitrogen and total nitrogen is used as the control index, and the removal effect of each stage reaches 90% and 70% respectively;

(3) Start-up and operation of the EGSB-MFC coupling system: connect granular activated carbon and high-efficiency denitrification bacteria to the reflow area, connect the cathode and anode conductive electrodes, and externally connect R=1000Ω resistance, and start the coupling system with 100% coking wastewater; start to produce Electricity and material degradation are stable.

(4) EGSB-MFC coupling: Coking wastewater is pumped into the water inlet through the inlet pump. Under the anaerobic environment of the EGSB anode area, the electrogenic bacteria decompose the organic matter in the coking wastewater to generate electrons and protons, which are transferred to the cathode return area through the external resistance ; The high-efficiency denitrification bacteria in the reflux area use the electrons transferred from the anode as electron donors to perform simultaneous nitrification and denitrification denitrification; the water inflow is controlled at 0.8L/h, the reflux ratio is 12.5~15, and the rising flow rate is 1.38~1.63m/h ; Aeration in the recirculation zone maintains DO at 0.3~0.5mg/L. After starting, the external resistance is maintained between 5~100Ω, the electron transfer rate is accelerated, and the material degradation is accelerated.

(5) EGSB-MFC coupling system: Coking wastewater is pumped into the water inlet of the system through a peristaltic pump. Under the anaerobic environment of the EGSB anode area, the organic matter in the coking wastewater is decomposed by electrogenic bacteria to generate electrons and protons, which are transferred through the external resistance Cathode recirculation area: The efficient denitrification bacteria in the recirculation area use the electrons transferred from the anode as electron donors to perform synchronous nitrification and denitrification denitrification; thus realizing synchronous carbon removal and denitrification to generate electricity.

Compared with a single system, the EGSB-MFC coupling system of the present invention has more advantages in the treatment of coking wastewater. It not only overcomes the problem of inhibition of toxic substances on denitrification bacteria, but also solves the problem of EGSB reactor When dealing with coking wastewater, the ammonia nitrogen treatment is not up to standard, and finally achieves the purpose of synchronous carbon and nitrogen removal, and can generate electricity and recover energy. The anode microorganisms of the present invention are derived from the anaerobic digestion sludge of the sewage treatment plant; the cathode microorganisms are derived from the nitrification tank sludge of the sewage treatment plant, and the coking wastewater with a COD concentration of 1000-2000 mg/L and an ammonia nitrogen concentration of 50-200 mg/L is treated , the COD removal process is mainly completed in the reaction zone of the EGSB reactor, and its removal rate is between 80% and 90%; The electrons generated during the removal are transferred to the cathode reflow area through the external circuit, and the electrode electrons are used as the electron donor for denitrification, and the removal rates of ammonia nitrogen and total nitrogen can reach 80-90% and 70-80% or more.

Claims (9)

1. it is a kind of for handling the EGSB-MFC coupled systems of coking wastewater difficult to degrade, including top, gas collector is set（1） EGSB reactors (2), the MFC systems (3) being coupled with EGSB reactors (2), it is characterised in that：The EGSB reactors (2) reaction zone is set as the anode chamber (2.1) of EGSB-MFC coupled systems, and the recirculating zone of the EGSB reactors is set as EGSB- The cathode chamber (2.2) of MFC coupled systems, by being equipped with cation-exchange membrane between anode chamber (2.1) and cathode chamber (2.2) (2.3) connecting tube connection；Setting conductive electrode (2.4) in the anode chamber (2.1) and cathode chamber (2.2), anode conducting electricity Pole connects outer connecting resistance (4) with cathode conductive electrode；Anode chamber (2.1) bottom is connected by porous water distributing plate (5) and intake Water tank (6) connects intake pump (7) between water tank inlet (6) and anode chamber (2.1), setting water outlet I at the top of anode chamber (2.1) (2.5), it is connect at the top of water outlet I (2.5) and cathode chamber (2.2), the side wall setting water outlet II of cathode chamber (2.2) top section (2.6)；Cathode chamber (2.2) bottom passes through communicating pipe jointed anode room (2.1) bottom.

2. a kind of EGSB-MFC coupled systems for being used to handle coking wastewater difficult to degrade according to claim 1, feature It is：The anode chamber and cathode chamber inner conductive electrode are graphite felt, and the work of attached microbial is filled around anode conductive electrode Property layer of charcoal (8)；The active carbon layer (9) of cathode conductive electrode both sides setting attachment denitrifier adheres to the activated carbon bottom of denitrifier Aerator (10), top conductor line connection are set.

3. a kind of EGSB-MFC coupled systems for being used to handle coking wastewater difficult to degrade according to claim 1, feature It is：Anode chamber's sidewall spacers set several sample taps (2.6).

4. a kind of EGSB-MFC coupled systems for being used to handle coking wastewater difficult to degrade according to claim 1, feature It is：The water tank inlet is high-order water tank inlet, and water tank inlet is higher than at the top of anode chamber.

5. a kind of EGSB-MFC coupled systems for being used to handle coking wastewater difficult to degrade according to claim 2, feature It is：The active carbon layer packed height of the attached microbial is the 1/3 of anode chamber's height, and the activated carbon is thin cylindrical particle Activated carbon, grain size 1.5-2mm are additionally provided with anaerobic activated sludge in the anode chamber, and the volume of anaerobic activated sludge is sun The 1/3 of pole room volume.

6. a kind of EGSB-MFC coupled systems for being used to handle coking wastewater difficult to degrade according to claim 2, feature It is：The activated carbon of the attachment denitrifier is buttress shaft shape granular activated carbon, and grain size 1.5-2mm, packed height is cathode chamber The 1/4 of height, efficient denitrification sludge is additionally provided in the cathode chamber, and volume is the 1/3 of cathode building volume.

7. a kind of EGSB-MFC coupled systems for being used to handle coking wastewater difficult to degrade according to claim 1, feature It is：The volume ratio of the anode chamber and cathode chamber is 1:10；The ratio of height to diameter of EGSB reactor reaction zones is 12:1, recirculating zone is high Diameter ratio is 1:1.

8. utilize a kind of any EGSB-MFC coupled systems for being used to handle coking wastewater difficult to degrade of claim 1 to 7 The method for the treatment of of Coking Wastewater, it is characterised in that：Using EGSB reactor granules sludge reaction areas as the anode region of coupled system, return The cathodic region that area is coupled system is flowed, is connected between anode region and cathodic region by the way that cation-exchange membrane is waterproof, in EGSB sun Under the anaerobic environment of polar region, electronics and proton are generated by producing electricity the organic matter in bacterium decomposition coking wastewater, is passed by external resistance Pass cathode recirculating zone；Recirculating zone efficient denitrification bacterium is electron donor using the electronics that anode passes over, and it is anti-to synchronize nitrification Nitrify denitrogenation.

9. the EGSB-MFC coupled systems degradation coking according to claim 8 utilized for handling coking wastewater difficult to degrade The method of waste water, it is characterised in that：It is as follows：

（1）The startup of EGSB reactors：Anaerobic sludge and active carbon particle are inoculated with, EGSB anaerobism is started using sanitary sewage anaerobism Reactor forms black anaerobic grain sludge；Then sanitary sewage and coking wastewater are according to 2:1、1:1、1:2、1:5、0:1 matches Than being tamed successively, with the removal of COD index in order to control, until each stage COD removals reach 80% ~ 90%；

（2）The screening and domestication of efficient denitrification bacterium：Inoculation of activated-sludge and active carbon particle, using 80 ~ 100mg/ of ammonia nitrogen concentration The nitrogenous effluent of a concentration of 2000 ~ 3500mg/L of L, COD carries out the screening of denitrifier, under aerobic condition, until ammonia nitrogen and total nitrogen are gone Except effect is up to until more than 90%；Then nitrogenous effluent is carried out with coking wastewater according to 2:1、1:1、1:2、1:5、0:1 proportioning Carry out domestication denitrifier successively, with the removal of ammonia nitrogen and total nitrogen index in order to control, each stage removal effect respectively reach 90% with And until more than 70%；

（3）The startup operation of EGSB-MFC coupled systems：By granular activated carbon and efficient denitrification bacterium access recirculating zone, negative and positive are connected Pole conductive electrode, the Ω resistance of external R=1000 carry out coupled system startup with 100% coking wastewater；

（4）EGSB-MFC is coupled：Coking wastewater is pumped into water inlet by intake pump, under the anaerobic environment of EGSB anode regions, leads to It crosses the organic matter that electricity production bacterium is decomposed in coking wastewater and generates electronics and proton, cathode recirculating zone is transmitted by external resistance；Recirculating zone Efficient denitrification bacterium is electron donor using the electronics that anode passes over, and synchronizes nitration denitrification denitrogenation；Control inflow For 0.8L/h, reflux ratio is 12.5 ~ 15,1.38 ~ 1.63m/h of upflow velocity；It is 0.3 ~ 0.5mg/L that recirculating zone aeration, which maintains DO,.