CN103094597B - Microbial fuel cell with function of efficiently and synchronously removing nitrogen and carbon - Google Patents

Abstract

The invention discloses a high-efficiency synchronous nitrogen and carbon removal microbial fuel cell. It is mainly composed of anaerobic digestion chamber and anaerobic ammonium oxidation chamber. By inoculating anaerobic digestion sludge in anaerobic digestion chamber and using organic wastewater as fuel, organic matter is decomposed by heterotrophic bacteria to release electrons, and anaerobic ammonium oxidation chamber is inoculated with anaerobic digestion chamber. Oxyammox sludge, nitrogen-containing wastewater is used as catholyte, nitrite nitrogen is used as electron acceptor, ammonia nitrogen and nitrite nitrogen are converted into nitrogen gas by anammox bacteria, and simultaneous denitrification and carbon removal are realized, while anaerobic digestion anode receives The electrons are transferred from the external circuit to the anammox cathode to realize electricity generation. The invention can treat organic wastewater and nitrogen-containing wastewater at the same time, realize high-efficiency synchronous denitrification and carbon removal to generate electricity, use nitrite nitrogen as the electron acceptor, reduce the operating cost of microbial fuel cells, and return the alkali-containing effluent from the anammox chamber to The anaerobic digestion chamber alleviates the acidification of the anolyte and improves the operation stability.

Description

Efficient simultaneous nitrogen and carbon removal microbial fuel cell

technical field

The invention relates to a biological fuel cell, in particular to a high-efficiency synchronous denitrification and carbon removal microbial fuel cell.

Background technique

With the rapid growth of the global economy, the pressure of energy shortage and environmental pollution has increased sharply, posing a serious threat to the sustainable development of human society. Microbial fuel cells can use microorganisms as catalysts to directly convert chemical energy into electrical energy. It is a new clean energy production technology and has become a research hotspot in the field of energy and environment.

Wastewater contains many pollutants and contains a lot of chemical energy. The use of MFCs technology to treat wastewater can not only control pollution, but also recycle electric energy. It is a major innovation in wastewater treatment technology. Because organic pollutants are the main pollutants in wastewater, a lot of research has been carried out on the use of MFCs to treat organic wastewater, and significant progress has been made.

Microbial fuel cell technology has shown good application prospects in the field of wastewater treatment, but there are still many problems to be solved when it is actually applied to wastewater treatment. First of all, the existing microbial fuel cells have achieved good results in the treatment of organic wastewater by using anaerobic digestion technology, but the denitrification effect is not satisfactory. In today's increasingly serious nitrogen pollution, the development of synchronous denitrification and carbon removal Microbial fuel cells have become the general trend; secondly, the high cost of the cathode limits its promotion and application, and cathode electron acceptors such as ferricyanide, permanganate and dichromate are not regenerated and need to be replaced frequently. The cathode loading of the body requires precious metal catalysts such as Pt, and the aeration consumes a lot of energy; again, the anolyte is prone to acidification, resulting in process instability. The microbial activity decreases, the battery output power decreases, and the battery stability decreases. In order to maintain the stability of the pH of the anolyte, a high-concentration phosphate buffer solution is often added to the anolyte, which is costly and easy to cause secondary pollution.

Anammox is a microbial reaction in which ammonia is used as the electron donor and nitrite is used as the electron acceptor to produce nitrogen. Due to its cost-effectiveness and high efficiency, the anammox process has become an important technology for denitrification of wastewater. The combination of anammox and anaerobic digestion technology can realize simultaneous denitrification and carbon removal; nitrous nitrogen can be used not only as an electron donor for anammox, but also as a cathode electron donor for microbial fuel cells, which can effectively reduce the The cathode cost of microbial fuel cells; anaerobic ammonium oxidation is an alkali-producing reaction, and its effluent is returned to the anode chamber, which can effectively alleviate the acidification of the anolyte, reduce maintenance costs, and improve its operational stability.

Aiming at the many defects of the existing microbial fuel cell technology, the present invention utilizes a highly efficient synchronous denitrification and carbon removal microbial fuel cell to treat organic wastewater and nitrogen-containing wastewater, realize synchronous wastewater denitrification and carbon removal and biological electricity generation, and significantly reduce wastewater treatment costs; Using nitrite, an anaerobic ammonium oxidation reactant, as an electron acceptor can effectively reduce the operating cost of microbial fuel cells; using anammox effluent to adjust the pH of the anolyte can effectively solve the problem of acidification of the anolyte, reduce maintenance costs, and improve microbial fuel cell efficiency. Improve the operation stability of the battery and increase its power generation.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a high-efficiency synchronous nitrogen and carbon removal microbial fuel cell.

High-efficiency synchronous denitrification and carbon removal microbial fuel cell includes anaerobic digestion sludge, water inlet pipe, anolyte, outlet pipe, anode, anaerobic digestion chamber, spare probe casing, flange, separation membrane, wire, load, anaerobic ammonia Oxidation chamber, cathode, catholyte, return pipe, anammox sludge; the lower side wall of the anaerobic digestion chamber is provided with a water inlet pipe, the upper side wall of the anaerobic digestion chamber is provided with an outlet pipe, and the anaerobic digestion chamber is provided with an anaerobic Digestion anode, anaerobic digestion chamber is equipped with anolyte, the anolyte is inoculated with anaerobic digestion sludge, anaerobic digestion anode is attached with anaerobic digestion sludge, the top of anaerobic digestion chamber is equipped with a spare probe sleeve, anaerobic ammonium oxidation The lower side wall of the chamber is provided with a water inlet pipe, the upper side wall of the anammox chamber is provided with a water outlet pipe, the anammox chamber is provided with an anammox cathode, and the anammox chamber is equipped with a catholyte, and the catholyte is inoculated with anaerobic ammonium oxide. Oxygen ammonia oxidation sludge, anammox sludge is attached to the anammox cathode, a spare probe sleeve is provided on the top of the anammox chamber, and the anaerobic digestion chamber and the anammox chamber are connected by a flange. A separation membrane is fixed on the top, the anaerobic digestion chamber and the anammox chamber are connected through a return pipe, and the two ends of the load are respectively connected with the anaerobic digestion anode and the anammox cathode through wires.

The ratio of the volume of the anaerobic digestion chamber to the volume of the anammox chamber is 1:1, the ratio of the volume of the anaerobic digestion sludge to the volume of the anaerobic digestion chamber is 1/10~1/4, and the anaerobic digestion chamber The ratio of the volume of the oxyammox sludge to the volume of the anammox chamber is 1/10~1/4.

The anolyte is organic waste water, and the catholyte is waste water containing ammonia and nitrite.

The conductive material of the anaerobic digestion anode and the anammox cathode is carbon paper, carbon cloth, carbon felt, graphite felt or graphite plate, and the distance between the anaerobic digestion anode and the anammox cathode is 2 to 10 cm , the ratio of the area of the anaerobic digestion anode to the volume of the anaerobic digestion chamber is 8~50 m ² :1 m ³ , and the ratio of the area of the anaerobic ammonium oxidation cathode to the volume of the anaerobic ammox chamber is 8~50 m ² :1 m ³

The material of the separation membrane is a cation exchange membrane, an anion exchange membrane, a proton exchange membrane, a bipolar membrane, a microfiltration membrane or an ultrafiltration membrane.

Compared with the prior art, the present invention has beneficial effects: (1) Combining anaerobic digestion, anammox and microbial fuel cell technology to realize high-efficiency synchronous denitrification and carbon removal to generate electricity and reduce wastewater treatment costs. (2) Use nitrite nitrogen, the reactant of anammox, as the electron donor to treat waste with waste and reduce the cost of the cathode. (3) Adjust the pH of the anolyte by using the anaerobic ammonium oxidation effluent, effectively solve the problem of acidification of the anolyte, reduce maintenance costs, improve the operational stability of the microbial fuel cell, and increase its power generation. Tests have proved that the high-efficiency synchronous denitrification and carbon removal microbial fuel cell developed on this basis can achieve high-efficiency denitrification and carbon removal, stable operation performance, and high power generation power.

Description of drawings

Figure 1 is a schematic diagram of the efficient synchronous denitrification and carbon removal microbial fuel cell;

In the figure: anaerobic digestion sludge 1, water inlet pipe 2, anolyte liquid 3, water outlet pipe 4, anode 5, anaerobic digestion chamber 6, spare probe casing 7, flange 8, separation membrane 9, wire 10, load 11 , anaerobic ammonium oxidation chamber 12, cathode 13, catholyte 14, return pipe 15, anammox sludge 16.

Detailed ways

As shown in Figure 1, the high-efficiency synchronous nitrogen and carbon removal microbial fuel cell includes anaerobic digestion sludge 1, water inlet pipe 2, anolyte 3, water outlet pipe 4, anode 5, anaerobic digestion chamber 6, spare probe casing 7, Flange 8, separation membrane 9, wire 10, load 11, anammox chamber 12, cathode 13, catholyte 14, return pipe 15, anammox sludge 16; the lower side wall of anaerobic digestion chamber 6 is provided with The water inlet pipe 2, the upper side wall of the anaerobic digestion chamber 6 is provided with an outlet pipe 4, the anaerobic digestion chamber 6 is provided with an anaerobic digestion anode 5, the anaerobic digestion chamber 6 is equipped with an anolyte 3, and the anolyte 3 is inoculated with anaerobic Digestion sludge 1, anaerobic digestion sludge 1 attached to anaerobic digestion anode 5, spare probe sleeve 7 is provided on the top of anaerobic digestion chamber 6, water inlet pipe 2 is provided on the lower side wall of anaerobic ammonium oxidation chamber 12, anaerobic The upper side wall of the ammonia oxidation chamber 12 is provided with an outlet pipe 4, the anammox chamber 12 is provided with an anammox cathode 13, the anammox chamber 12 is equipped with a catholyte 14, and the catholyte 14 is inoculated with anammox Sludge 16, anammox sludge 16 attached to the anammox cathode 13, a spare probe casing 7 is arranged on the top of the anammox chamber 12, and the anaerobic digestion chamber 6 and the anammox chamber 12 pass through the flange 8 connection, the flange 8 is fixed with a separation membrane 9, the anaerobic digestion chamber 6 and the anammox chamber 12 are connected through the return pipe 15, and the two ends of the load 11 are respectively connected to the anaerobic digestion anode 5 and the anammox chamber through the wire 10 The cathode 13 is connected.

The ratio of the volume of the anaerobic digestion chamber 6 to the volume of the anammox chamber 12 is 1:1, and the ratio of the volume of the anaerobic digestion sludge 1 to the volume of the anaerobic digestion chamber 6 is 1/10~1 /4, the ratio of the volume of the anammox sludge 16 to the volume of the anammox chamber 12 is 1/10~1/4.

The anolyte 3 is organic waste water, and the catholyte 14 is waste water containing ammonia and nitrite.

The conductive material of described anaerobic digestion anode 5 and anammox cathode 13 is carbon paper, carbon cloth, carbon felt, graphite felt or graphite plate, the distance between anaerobic digestion anode 5 and anammox cathode 13 The ratio of the area of the anaerobic digestion anode 5 to the volume of the anaerobic digestion chamber 6 is 8 to 50 m ² : 1 m ³ , the area of the anaerobic ammonium oxidation cathode 13 to the volume of the anaerobic ammonium oxidation chamber 12 The ratio is 8~50 m ² : 1 m ³

The material of the separation membrane 9 is a cation exchange membrane, an anion exchange membrane, a proton exchange membrane, a bipolar membrane, a microfiltration membrane or an ultrafiltration membrane.

The anaerobic digestion sludge is inoculated into the anaerobic digestion chamber, the organic wastewater is introduced into the anaerobic digestion chamber as fuel, the organic matter is decomposed by heterotrophic bacteria to release electrons, and the carbon removal process is completed, and the anammox chamber is inoculated with the anammox sludge, containing Nitrogen wastewater is introduced into the anammox chamber, nitrite nitrogen is used as the electron donor, ammonia nitrogen and nitrite nitrogen are converted into nitrogen by anammox bacteria, and the denitrification process is completed. The electrons released by the decomposition of organic matter in the anolyte are anaerobically digested Anode reception, anaerobic digestion The electrons received by the anode are transferred to the anammox cathode through the connecting wire and the load, and the electrons are used for the reduction of nitrite nitrogen in the catholyte to realize electricity generation. The oxygen digestion chamber alleviates the problem of acidification of the anolyte and makes the microbial fuel cell run stably.

Claims (1)

1. A highly efficient synchronous denitrification and carbon removal microbial fuel cell, characterized in that it includes anaerobic digestion sludge (1), water inlet pipe (2), anolyte (3), outlet pipe (4), anode (5) , anaerobic digestion chamber (6), spare probe sleeve (7), flange (8), separation membrane (9), wire (10), load (11), anammox chamber (12), cathode ( 13), catholyte (14), return pipe (15), anammox sludge (16); the lower side wall of the anaerobic digestion chamber (6) is provided with a water inlet pipe (2), and the anaerobic digestion chamber (6) The upper side wall is provided with an outlet pipe (4), the anaerobic digestion chamber (6) is provided with an anode (5), the anaerobic digestion chamber (6) is equipped with an anolyte (3), and the anolyte (3) is inoculated with anaerobic Digested sludge (1), anaerobic digested sludge (1) attached to the anode (5), spare probe casing (7) on the top of the anaerobic digestion chamber (6), lower side of the anaerobic ammonium oxidation chamber (12) The wall is provided with a water inlet pipe (2), the upper side wall of the anammox chamber (12) is provided with an outlet pipe (4), the anaerobic ammonium oxidation chamber (12) is provided with a cathode (13), and the anammox chamber ( 12) The catholyte (14) is installed inside, the anammox sludge (16) is inoculated in the catholyte (14), the anammox sludge (16) is attached to the cathode (13), and the anammox chamber (12 ) is equipped with a spare probe casing (7), the anaerobic digestion chamber (6) and the anammox chamber (12) are connected by a flange (8), and a separation membrane (9) is fixed on the flange (8), The anaerobic digestion chamber (6) and the anammox chamber (12) are connected through a return pipe (15), and the two ends of the load (11) are respectively connected to the anode (5) and the cathode (13) through wires (10); The ratio of the volume of the anaerobic digestion chamber (6) to the volume of the anammox chamber (12) is 1:1, and the ratio of the volume of the anaerobic digestion sludge (1) to the volume of the anaerobic digestion chamber (6) 1/10~1/4, the ratio of the volume of the anammox sludge (16) to the volume of the anammox chamber (12) is 1/10~1/4; the anolyte (3) It is organic waste water, and catholyte (14) is waste water containing ammonia and nitrite. 2. A high-efficiency synchronous denitrification and carbon removal microbial fuel cell according to claim 1, characterized in that the conductive materials of the anode (5) and cathode (13) are carbon paper, carbon cloth, carbon felt, graphite Felt or graphite plate, the distance between the anode (5) and the cathode (13) is 2~10cm, the ratio of the area of the anode (5) to the volume of the anaerobic digestion chamber (6) is 8~50 m ² :1 m ^3. The ratio of the area of the cathode (13) to the volume of the anammox chamber (12) is 8-50 m ² :1 m ³ . 3. A high-efficiency synchronous denitrification and carbon removal microbial fuel cell according to claim 1, characterized in that the material of the separation membrane (9) is a cation exchange membrane, anion exchange membrane, proton exchange membrane, bipolar membrane , microfiltration membrane or ultrafiltration membrane.