阅读说明：本技术 一种促进剩余污泥微生物电解产氢的方法 (Method for promoting hydrogen production by excess sludge microorganism electrolysis ) 是由 张心悦 胡凯 谢雯怡 潘泓哲 于 2018-08-31 设计创作，主要内容包括：一种促进剩余污泥微生物电解产氢的方法,属于剩余污泥微生物电解产氢技术领域。所述方法包括：S1、以城镇污水处理厂剩余污泥为接种物,利用单室MEC富集阳极产电菌；S2、利用臭氧技术破解剩余污泥,得到臭氧预处理后的剩余污泥；S3、室温下,外加电压,以预处理后的污泥为底物,运行单室MEC,实现剩余污泥产氢。针对现有技术中剩余污泥中有机质水解速率慢、氢气转化回收效率低等问题,本发明提供一种促进剩余污泥微生物电解产氢的方法,具有提升剩余污泥中的有机质水解速率、提高氢气转化回收效率等优点,能够实现剩余污泥的高效产氢。(A method for promoting hydrogen production by excess sludge microorganism electrolysis belongs to the technical field of hydrogen production by excess sludge microorganism electrolysis. The method comprises the following steps: s1, taking excess sludge of a municipal wastewater treatment plant as an inoculum, and enriching anode electrogenic bacteria by using single-chamber MEC; s2, breaking the excess sludge by using an ozone technology to obtain excess sludge after ozone pretreatment; and S3, applying voltage at room temperature, operating the single-chamber MEC by taking the pretreated sludge as a substrate, and realizing hydrogen production by the residual sludge. Aiming at the problems of slow hydrolysis rate of organic matters in the excess sludge, low hydrogen conversion recovery efficiency and the like in the prior art, the invention provides the method for promoting the hydrogen production by the excess sludge microorganism electrolysis, which has the advantages of improving the hydrolysis rate of the organic matters in the excess sludge, improving the hydrogen conversion recovery efficiency and the like, and can realize the high-efficiency hydrogen production of the excess sludge.)

1. A method for promoting the hydrogen production by the electrolysis of excess sludge microorganisms is characterized by comprising the following steps:

taking the excess sludge of the urban sewage treatment plant as an inoculum, and mixing the excess sludge of the urban sewage treatment plant and the solution A according to the volume ratio of (0.5-1): (1-2.5) mixing to obtain a mixed solution B, wherein the solution A is prepared according to the following proportion: 1.5g NaAc and 2.4145g KH were added to 1L water₂PO₄、5.6135g K₂HPO₄、0.31g NH₄Cl、0.13g KCl；

Adding the mixed solution B into the initial single-chamber microbial electrolytic cell to be close to the inner top of the device, then applying voltage of 0.5-0.9V at the temperature of 22-28 ℃, starting the initial single-chamber microbial electrolytic cell, recording the voltage value of an external circuit series resistor, replacing a new solution B when the maximum voltage value tends to be stable, thereby completing an operation period, completing enrichment of anode electrogenesis bacteria when the maximum voltage stable value of the initial single-chamber microbial electrolytic cell reappears for at least 3 operation periods, and then taking the anode as the anode when the initial single-chamber microbial electrolytic cell treats residual sludge;

step three, introducing ozone into the surplus sludge of the urban sewage treatment plant to be treated, wherein the adding amount of the ozone is O₃The SS in the excess sludge is 235-275 mg/g, and the excess sludge is pretreated to obtain treated excess sludge mixed liquor C;

step four, taking the treated residual sludge mixed liquor C as a substrate, adding the treated residual sludge mixed liquor C into the single-chamber microbial electrolytic cell treated in the step two, operating the single-chamber microbial electrolytic cell at 22-28 ℃, sequentially adding the solution A, the trace element solution D and the vitamin solution E into the single-chamber microbial electrolytic cell, and mixing the sum of the volumes of the solution A, the trace element solution D and the vitamin solution EThe volume ratio of the combined liquid C is (1-2.5) to (0.5-1), then a resistor is connected in series between two electrodes of the single-chamber microbial electrolytic cell, an external voltage of 0.5-0.9V is applied, and when the gas production rate is not increased or the voltage at two ends of the resistor is obviously reduced, the periodic treatment is considered to be finished, wherein the trace element solution D is prepared according to the following proportion: 1.5g of triacetic acid and 3.0g of MgSO₄•7H₂O、0.5g MnSO₄•2H₂O 、 1.0g NaCl、0.1g FeSO₄•7H₂O 、0.1g CoCl₂、0.1g CaCl₂•2H₂O 、 0.1g ZnSO₄、0.01g CuSO₄•5H₂O 、0.01g AlK(SO₄)₂、0.01g H₃BO₃、0.025g Na₂MoO₄、0.024g NiCl•6H₂O and vitamin solution E are prepared according to the following proportion: 2mg of biotin, 2mg of folic acid, 10mg of vitamin B6, 5mg of vitamin B1, 5mg of vitamin B2, 5mg of nicotinic acid, 5mg of calcium pantothenate, 0.1mg of vitamin B12, 5mg of 4-aminobenzoic acid, and 5mg of lipoic acid were added to 1L of water.

2. The method for promoting hydrogen production by excess sludge microbial electrolysis according to claim 1, wherein in the second step, the anode of the initial single-chamber microbial electrolysis cell is a graphite fiber brush electrode, and the cathode is a carbon cloth electrode.

3. The method for promoting microbial electrolysis hydrogen production of excess sludge according to claim 1, wherein in the first step, excess sludge of a town sewage treatment plant is used as an inoculum, and the excess sludge of the town sewage treatment plant is mixed with the solution A according to a volume ratio of 1:2 to obtain a mixed solution B.

4. The method for promoting the hydrogen production by the microbial electrolysis of the excess sludge as claimed in claim 1, wherein in the second step, the mixed liquor B is added into the initial single-chamber microbial electrolytic cell to be close to the top in the device, and then the initial single-chamber microbial electrolytic cell is started at the temperature of 25 ℃ and the applied voltage of 0.7V.

5. The method for promoting hydrogen production by excess sludge microorganism electrolysis as claimed in claim 1, wherein the ozone adding amount in the third step is O₃SS in the residual sludge is 250 mg/g.

6. The method for promoting hydrogen production by excess sludge microorganism electrolysis according to claim 1, wherein in the fourth step, the treated excess sludge mixed liquor C is used as a substrate, the treated excess sludge mixed liquor C is added into the single-chamber microorganism electrolytic cell treated in the second step, then the single-chamber microorganism electrolytic cell is operated at 25 ℃, the solution a, the trace element solution D and the vitamin solution E are sequentially added into the single-chamber microorganism electrolytic cell, and the volume ratio of the total volume of the solution a, the trace element solution D and the vitamin solution E to the mixed liquor C is 2:1, then, a resistor is connected in series between two poles of the single-chamber microbial electrolytic cell, and an external voltage of 0.7V is applied.

7. The method for promoting hydrogen production by excess sludge microbial electrolysis according to claim 1 or 2, wherein in the second step, the anode and the cathode of the initial single-chamber microbial electrolysis cell are sequentially subjected to ultrasonic cleaning in acetone, ethanol and pure water for 8-12 min before use, and then are subjected to high-temperature heat treatment at 400-500 ℃ for 25-35 min.

8. The method for promoting the microbial electrolysis of the excess sludge to produce hydrogen according to claim 7, wherein in the second step, the anode and the cathode of the initial single-chamber microbial electrolysis cell are sequentially subjected to ultrasonic cleaning in acetone, ethanol and pure water for 10min before use, and then are subjected to high-temperature heat treatment at 450 ℃ for 30 min.

9. The method for promoting hydrogen production by excess sludge microbial electrolysis as claimed in claim 1, wherein in the third step, the flow rate of ozone is 0.5-1.0L/min, and the concentration of ozone is 25-35 mg/min.

Technical Field

The invention relates to the technical field of excess sludge microorganism electrolysis hydrogen production, in particular to a method for promoting excess sludge microorganism electrolysis hydrogen production.

Background

With the continuous perfection of urban sewage treatment facilities in China and the improvement of sewage treatment rate, the yield of excess sludge is continuously increased. In 2020, the annual sludge production of China can break through 6000 million tons. The excess sludge is a byproduct of biochemical treatment of urban sewage treatment plants, mainly comprises organic matters, bacteria, inorganic particles, colloid and the like, and has high water content (more than 99 percent) because the sludge contains more organic matters and is also called as 'biomass'.

At present, a concentration-dehydration treatment process is commonly adopted for excess sludge in a sewage plant, and unstable dehydrated sludge can cause harm to human health if the sludge is not properly treated in a subsequent treatment process. For a few large sewage plants with anaerobic digestion processes, the digester is also in a semi-out or non-operational state.

A Microbial Electrolysis Cell (MEC) is an emerging bioelectrochemical technology, and microorganisms are utilized to degrade organic matters in sewage to generate hydrogen or methane. At present, MEC substrate research is actively being conducted around organic wastewater and excess sludge.

The existing excess sludge treatment and disposal technology has a plurality of problems, which are highlighted as follows: difficulty in promotion of anaerobic digestion, easiness in causing secondary pollution to the environment, insufficient development of biomass energy of excess sludge and the like. Under the background, the development of new treatment technologies, especially emerging technologies for synchronously treating sludge and recovering biomass energy, has great development prospects.

Disclosure of Invention

The technical problem to be solved is as follows: aiming at the problems of slow hydrolysis rate of organic matters in the excess sludge, low hydrogen conversion recovery efficiency and the like in the prior art, the invention provides the method for promoting the hydrogen production by the excess sludge microorganism electrolysis, which has the advantages of improving the hydrolysis rate of the organic matters in the excess sludge, improving the hydrogen conversion recovery efficiency and the like, and can realize the high-efficiency hydrogen production of the excess sludge.

The technical scheme is as follows: a method for promoting hydrogen production by excess sludge microorganism electrolysis, comprising the following steps:

taking the excess sludge of the urban sewage treatment plant as an inoculum, and mixing the excess sludge of the urban sewage treatment plant and the solution A according to the volume ratio of (0.5-1): (1-2.5) mixing to obtain a mixed solution B, wherein the solution A is prepared according to the following proportion: 1.5g NaAc and 2.4145g KH were added to 1L water₂PO₄、5.6135g K₂HPO₄、0.31g NH₄Cl、0.13g KCl；

Adding the mixed solution B into the initial single-chamber microbial electrolytic cell to be close to the inner top of the device, then applying voltage of 0.5-0.9V at the temperature of 22-28 ℃, starting the initial single-chamber microbial electrolytic cell, recording the voltage value of an external circuit series resistor, replacing a new solution B when the maximum voltage value tends to be stable, thereby completing an operation period, completing enrichment of anode electrogenesis bacteria when the maximum voltage stable value of the initial single-chamber microbial electrolytic cell reappears for at least 3 operation periods, and then taking the anode as the anode when the initial single-chamber microbial electrolytic cell treats residual sludge;

step three, introducing ozone into the surplus sludge of the urban sewage treatment plant to be treated, wherein the adding amount of the ozone is O₃The SS in the excess sludge is 235-275 mg/g, and the excess sludge is pretreated to obtain treated excess sludge mixed liquor C;

step four, taking the treated residual sludge mixed liquor C as a substrate, adding the treated residual sludge mixed liquor C into the single-chamber microbial electrolytic cell treated in the step two, operating the single-chamber microbial electrolytic cell at 22-28 ℃, sequentially adding a solution A, a trace element solution D and a vitamin solution E into the single-chamber microbial electrolytic cell, wherein the volume ratio of the sum of the volumes of the solution A, the trace element solution D and the vitamin solution E to the mixed liquor C is (1-2.5): (0.5-1), then serially connecting resistors between two electrodes of the single-chamber microbial electrolytic cell, applying an external voltage of 0.5-0.9V, and when the gas production is not increased or the voltage at two ends of the serial resistor is obviously reduced, determining that the periodic treatment is finished, wherein the trace element solution D is prepared according to the following proportion: 1.5g of triacetic acid and 3.0g of MgSO₄·7H₂O、0.5g MnSO₄·2H₂O、1.0g NaCl、0.1g FeSO₄·7H₂O、0.1gCoCl₂、0.1g CaCl₂·2H₂O、0.1g ZnSO₄、0.01g CuSO₄·5H₂O、0.01g AlK(SO₄)₂、0.01g H₃BO₃、0.025g Na₂MoO₄、0.024g NiCl·6H₂O and vitamin solution E are prepared according to the following proportion: adding 2mg biotin, 2mg folic acid, 10mg vitamin into 1L waterB6, 5mg vitamin B1, 5mg vitamin B2, 5mg niacin, 5mg calcium pantothenate, 0.1mg vitamin B12, 5mg 4-aminobenzoic acid, 5mg lipoic acid.

Preferably, in the second step, the anode of the initial single-chamber microbial electrolytic cell is a graphite fiber brush electrode, and the cathode is a carbon cloth electrode.

Preferably, in the first step, the excess sludge of the urban sewage treatment plant is used as an inoculum, and the excess sludge of the urban sewage treatment plant and the solution A are mixed according to the volume ratio of 1:2 to obtain a mixed solution B.

Preferably, in the second step, the mixed liquor B is added into the initial single-chamber microbial electrolytic cell to be close to the top in the device, and then the initial single-chamber microbial electrolytic cell is started at the temperature of 25 ℃ and the applied voltage of 0.7V.

Preferably, the ozone adding amount in the third step is O₃SS in the residual sludge is 250 mg/g.

Preferably, in the fourth step, the treated residual sludge mixed solution C is used as a substrate, the treated residual sludge mixed solution C is added into the single-chamber microbial electrolytic cell treated in the second step, then the single-chamber microbial electrolytic cell is operated at 25 ℃, the solution a, the trace element solution D and the vitamin solution E are sequentially added into the single-chamber microbial electrolytic cell, and the volume ratio of the sum of the volumes of the solution a, the trace element solution D and the vitamin solution E to the mixed solution C is 2:1, then, a resistor is connected in series between two poles of the single-chamber microbial electrolytic cell, and an external voltage of 0.7V is applied.

Preferably, the anode and the cathode of the initial single-chamber microbial electrolytic cell in the second step are sequentially ultrasonically cleaned in acetone, ethanol and pure water for 8-12 min before use, and then are subjected to high-temperature heat treatment at 400-500 ℃ for 25-35 min.

Preferably, the anode and the cathode of the initial single-chamber microbial electrolytic cell in the second step are sequentially ultrasonically cleaned in acetone, ethanol and pure water for 10min before use, and then are subjected to high-temperature heat treatment at 450 ℃ for 30 min.

Preferably, the flow rate of the ozone in the third step is 0.5-1.0L/min, and the concentration of the ozone is 25-35

mg/min。

Has the advantages that: 1. according to the method for promoting the microbial electrolysis production of hydrogen from excess sludge by using the ozone technology, the excess sludge is broken by ozone, the floc structure is damaged, intracellular substances are released, the hydrolysis rate of the sludge is increased, and the sludge treatment effect of MEC is enhanced. The test shows that: under the condition of room temperature (25 +/-3 ℃), the total removal rate of VSS reaches 74.5%, and the total removal rate of TCOD reaches 77.6%.

2. The method treats the graphite fiber brush electrode and the carbon cloth electrode for 30min at the high temperature of 450 ℃, increases the roughness and the surface area of the electrode surface, and is beneficial to the adhesion of anode electrogenesis bacteria and the coating of a cathode catalyst.

3. The invention successfully realizes the stabilization, reduction and resource utilization of the excess sludge, and has the advantages of simple principle, convenient operation, less equipment and instrument investment, strong practicability and wide applicability.

Drawings

FIG. 1 is a schematic diagram of the process for promoting the production of hydrogen by the electrolysis of excess sludge microorganisms by using the ozone technology.

The reference numerals in the figures represent the following: 1. an ozone generator; 2. a sludge breaking device by ozone; 3. an external power supply; 4. a series resistor; 5. a sludge inlet; 6. a gas collection hole; 7. a carbon fiber brush; 8. and (3) carbon cloth.

Detailed Description

The invention is further described with reference to the following figures and specific examples.