Method for rapidly starting dye-organic wastewater anaerobic co-metabolism system based on S-nZVI

Abstract

The invention relates to the technical field of water pollution control, in particular to a method for rapidly starting a dye-organic wastewater anaerobic co-metabolism system based on S-nZVI, which comprises the following steps: S1, preparing S-nZVI, and S2, optimizing an anaerobic treatment method of dye-organic wastewater by S-nZVI. According to the method, the sulfur-doped nano-iron is applied to a dye-organic wastewater anaerobic co-metabolism system for the first time, the dispersity of the nano-iron is improved through sulfur doping, the hydrogen evolution reaction is inhibited through sulfur doping, and reduction damage of cell membranes is avoided; meanwhile, the formation of FeS endows the nano-iron with stronger conductivity, electron transfer pathways of microorganisms are enriched, the electron transfer efficiency is improved, the optimization method not only realizes efficient degradation of the dye, but also effectively overcomes acid inhibition in the anaerobic digestion process under dye stress, and the degradation efficiency of the dye is improved. And quick start and methane recovery of the reactor can be realized without domesticating the sludge.

Description

Technical Field

[0001] The invention relates to the technical field of water pollution control, and in particular to a method for quickly starting a dye-organic wastewater anaerobic co-metabolism system based on S-nZVI. Background Art

[0002] The textile, printing and dyeing, papermaking and other industries produce a large amount of dye wastewater, accounting for about 20% of the total global industrial wastewater. Among them, the amount of azo dyes accounts for 60-70% of the total amount of synthetic dyes. It is one of the characteristic pollutants that must be paid attention to in dye wastewater. If it is not handled properly, it may cause serious environmental problems and endanger human health. At present, the main treatment technologies for azo dyes include physical methods, chemical methods, biological methods and their combined processes. Anaerobic treatment is a green and economical pretreatment process that improves the biodegradability of refractory wastewater by converting macromolecular organic matter. In this process, azo dyes are converted into aromatic amines, which are easily degraded by microorganisms under aerobic conditions.

[0003] However, the anaerobic treatment of dye wastewater has not achieved satisfactory results so far. The reasons are: first, azo dyes have a large molecular weight and strong polarity, making it difficult for them to enter the cell and be degraded by microorganisms. Secondly, as a typical low carbon-nitrogen ratio wastewater, the insufficient source of electron donors and the competition of other electron acceptors lead to insufficient biodegradation efficiency of azo dyes. Therefore, dye wastewater usually metabolizes with high organic wastewater to provide sufficient electron sources for dye degradation. But in turn, the inhibitory effect of this mode of co-metabolism on anaerobic digestion is usually worthy of attention. Due to the biological toxicity of azo dyes and their reduction products, aromatic amines, the activity of acidogenic and methanogenic microorganisms can easily lose balance, resulting in poor mutual nutrition metabolism and poor system stability. It is reported that methanogens are more sensitive to adverse environments than acidogenic bacteria, which leads to the continuous accumulation of volatile fatty acids (VFAs) (mainly acetic acid, propionic acid and butyric acid) during anaerobic digestion due to the obstruction of conversion, and the reactor fails to start or collapses due to excessive acidification during operation. Therefore, it is undoubtedly of great practical significance to smoothly start the reactor from potential failures and maintain the stability of the cometabolic system, ensuring the efficient degradation of the dye while achieving efficient energy recovery.

[0004] In recent years, nano-iron materials have been used in anaerobic digestion systems. Due to their strong reducing properties and electrical conductivity, nano-iron can be used as a CO 2The reduced electron donors and enrichment of hydrogenophilic methanogens reduce the hydrogen partial pressure of the anaerobic digestion process, which indirectly makes the conversion of VFAs easier to occur thermodynamically. On the other hand, a large number of studies have reported that conductors or semiconductor materials can enhance the extracellular electron transfer (EET) of microorganisms. Therefore, the extracellular degradation of azo dyes may be enhanced, which not only saves the energy consumed by entering the cell across the membrane and improves the electron transfer efficiency, but also alleviates the toxic effects of azo dyes on anaerobic microorganisms when they enter the cell. In addition, methanogens may use extracellular electrons to establish an interspecific direct electron transfer mechanism (DIET). DIET is achieved by conductive pili or cytochrome C to achieve electron transfer between microorganisms. This symtrophic metabolism is more favorable than interspecific hydrogen transfer (IHT) in terms of energy utilization. Therefore, even under unfavorable conditions (dye stress) or high concentrations of VFAs, the thermodynamic bottleneck in the symtrophic metabolism process can be overcome, and VFAs can be degraded and methane can be produced through the more energetically favorable DIET pathway. It is worth mentioning that the establishment of DIET is not only beneficial to CO 2 Reduction can also enhance the acetogenic methanogenesis process. However, affected by surface forces such as van der Waals force and magnetic force, nano-iron is easy to agglomerate and its reaction activity is reduced. At the same time, a large number of studies have reported that the effect of nano-iron on microorganisms is dose-dependent. This is mainly due to the strong reducing property of nano-iron, which on the one hand leads to the reduction and destruction of microbial cell membranes. On the other hand, in aqueous media, nano-iron is easy to react with protons to produce hydrogen. Excessive hydrogen partial pressure not only leads to the waste of electrons, but also affects the thermodynamic equilibrium of the anaerobic digestion process.

[0005] Sulfur doping technology provides an opportunity to solve the above-mentioned deficiencies in the application of nano-iron. Introducing a sulfiding agent during the preparation of nano-iron to form FeS as a skeleton can effectively improve the dispersibility of nano-iron particles. FeS has a certain hydrophobicity, which is conducive to regulating the hydrogen evolution reaction of nano-iron, thereby avoiding excessive hydrogen partial pressure. In addition, FeS has excellent conductivity and can be used as an active site for nano-iron, which improves the conductivity of nano-iron while alleviating the reduction damage to the microbial cell membrane. Therefore, we speculate that in the co-metabolism system of dye wastewater and organic wastewater, sulfur doping will enhance the improvement of nano-iron on anaerobic digestion based on thermodynamics, kinetics, etc., and provide a more suitable environmental condition for microorganisms, while further optimizing the proton-electron transfer network and microbial community structure of pollutant degradation and methanogenesis. Thus, an energy-saving, efficient and stable anaerobic metabolic system is constructed. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a method for quickly starting a dye-organic wastewater anaerobic cometabolism system based on S-nZVI.

[0007] The technical solution of the present invention is: a method for quickly starting a dye-organic wastewater anaerobic co-metabolism system based on S-nZVI, comprising the following steps:

[0008] S1. Preparation of S-nZVI

[0009] In an inert atmosphere, sodium dithionite and ferrous sulfate heptahydrate with a concentration of 0.1 to 0.15 mol / L are dissolved in ultrapure water at a molar ratio of S:Fe=(0.1 to 0.5):1, and stirred to obtain a mixed solution. Then, potassium borohydride with a concentration of 0.4 to 0.5 mol / L is added dropwise to the mixed solution at a dropping rate of 8 to 12 mL / min through a peristaltic pump for 18 to 22 min. After centrifugation, the supernatant is removed and washed with ultrapure water and ethanol in turn. After vacuum drying, sulfur-doped nano-iron particles are obtained, which are recorded as S-nZVI.

[0010] S2 and S-nZVI Optimization of Anaerobic Treatment of Dye-Organic Wastewater

[0011] The anaerobic digestion sludge is added into a serum bottle so that the concentration of the anaerobic digestion sludge is 4-6 gTS / L, and then the S-nZVI obtained in step S1 is added into the anaerobic digestion sludge in an amount of 0.4-0.6 g / L, and 120-180 mL of dye-organic wastewater is introduced, and then the pH is adjusted to pH=6.8-7.2 by a pH regulator, and after nitrogen stripping for 25-35 minutes, the mixture is placed in a shaker for anaerobic biological treatment for 10-14 hours; the pH regulator is 0.1 mol / L HCl solution or 0.1 mol / L NaOH solution; the S-nZVI in the above dosage can have better ability to enrich functional microorganisms and provide exogenous electrons, so that VFAs can be efficiently converted into methane under the adverse conditions of dye stress.

[0012] Furthermore, in step S1, the purity of the inert atmosphere is 99-99.9%, the stirring speed is 180-220 rpm, and the stirring time is 25-40 min;

[0013] Note: The S-nZVI prepared under the above parameters has better performance and can effectively improve the dispersion of nano-iron, thereby inhibiting the hydrogen evolution reaction and further avoiding the destruction of nano-iron, thereby optimizing the performance of nano-iron.

[0014] Furthermore, the vacuum drying method is: placing the washed material in a vacuum drying oven at a temperature of 45 to 55° C. and drying for 22 to 26 hours;

[0015] Note: Drying at the above temperature can ensure the drying efficiency while avoiding the damage to S-nZVI caused by excessively high temperature, thereby effectively ensuring the optimization effect of S-nZVI on nano-iron.

[0016] Furthermore, in step S1, the centrifugal speed is 5900-6100 rpm, and the centrifugal time is 6-10 min;

[0017] Note: The sulfur-doped nano-iron particles obtained under the above centrifugal conditions are more uniform and have a better optimization effect on the dye-organic wastewater anaerobic co-metabolism system.

[0018] Further, in step S1, the mass concentration of the ethanol is 93-97%;

[0019] Note: The above mass concentration of ethanol can not only effectively wash sulfur-doped nano-iron but also be easy to evaporate and dry.

[0020] Further, in step S2, the composition of the dye-organic wastewater is: methyl orange (MO): 200 mg / L, glucose: 2000 mg / L, KH 2 PO 4 :25mg / L,NH 4 Cl: 100 mg / L, MgCl 2 :20mg / L, CaCl 2 : 30mg / L, EDTA: 5mg / L, FeSO 4 7H 2 O: 2mg / L, ZnSO 4 7H 2 O: 1mg / L, MnCl 2 ·4H 2 O: 3mg / L, H 3 BO 4 :30mg / L,CoCl 2 6H 2 O: 20mg / L, CuCl 2 ·2H 2 O: 1mg / L, NiCl 2 6H 2 O: 2mg / L, Na 2 MoO 4 ·2H 2 O: 3mg / L;

[0021] Description: The reason for adding glucose in dye-organic wastewater treatment is mainly to provide additional carbon source and enhance the biodegradation ability of microorganisms to promote the growth and metabolic activities of microorganisms, thereby improving the efficiency and stability of the entire wastewater treatment system.

[0022] Further, in step S2, the rotation speed of the shaking table is 140-160 rpm and the temperature is 36-38°C;

[0023] Note: Appropriate low-speed shaking helps maintain anaerobic conditions and promote the metabolic activities of anaerobic microorganisms, thereby improving the anaerobic biological treatment effect of samples after nitrogen stripping.

[0024] Compared with the existing dye-organic wastewater anaerobic co-metabolism system, the beneficial effects of the present invention are:

[0025] (1) The present invention is the first to apply sulfur-doped nano-iron to the dye-organic wastewater anaerobic co-metabolism system. The dispersibility of nano-iron is improved by sulfur doping, and the hydrogen evolution reaction is inhibited by sulfur doping, and the reduction and destruction of cell membrane caused by direct contact between nano-iron and microorganisms is avoided, thereby improving the biocompatibility of nano-iron. At the same time, the formation of FeS gives nano-iron stronger conductivity, which is beneficial to enrich the electron transfer pathways of microorganisms and improve the electron transfer efficiency. It not only achieves efficient degradation of dyes, but also effectively overcomes the acid inhibition of anaerobic digestion process under dye stress, and can achieve rapid startup of the reactor and methane recovery without acclimating sludge.

[0026] (2) For dye degradation, the formation of the conductive layer FeS is beneficial to improving the extracellular electron transfer ability of microorganisms. The degradation of dyes is transferred from intracellular to extracellular, which not only avoids the limitation of dye transmembrane transport, but also alleviates the toxic effects caused by pollutants entering cells.

[0027] (3) For the anaerobic digestion process, S-nZVI is beneficial to enrich functional microorganisms and provide exogenous electrons to convert CO 2 reduction to methane and establishment of a direct interspecific electron transfer mechanism, thereby efficiently converting VFAs to methane even under adverse conditions (dye stress). BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a comparison diagram of the removal of methyl orange (MO) of the present invention;

[0029] Figure 2 is a comparison diagram of the accumulation of VFAs during the anaerobic digestion process of the present invention;

[0030] Figure 3 It is a comparison diagram of COD removal of the present invention;

[0031] Figure 4 It is a comparison diagram of methane production during the anaerobic digestion process of the present invention. DETAILED DESCRIPTION

[0032] In order to further illustrate the method adopted by the present invention and the effect achieved, the technical solution of the present invention will be clearly and completely described in combination with experiments below.

[0033] Example 1: A method for quickly starting a dye-organic wastewater anaerobic cometabolism system based on S-nZVI, comprising the following steps:

[0034] S1. Preparation of S-nZVI

[0035] In an inert atmosphere with a purity of 99.5%, sodium dithionite and 0.13 mol / L ferrous sulfate heptahydrate were dissolved in 50 L of ultrapure water at a molar ratio of S:Fe=0.3:1, and the mixture was stirred at 200 rpm to obtain a mixed solution. Then, 0.45 mol / L potassium borohydride was added to the mixed solution at a dropping rate of 10 mL / min by a peristaltic pump for 20 min to carry out a reduction reaction. The mixture was centrifuged at a centrifugal speed of 6000 rpm for 8 min, the supernatant was removed and washed with ultrapure water and 95% ethanol in turn, and dried in a vacuum drying oven at a temperature of 50°C for 24 h to obtain sulfur-doped nano-iron particles, recorded as S-nZVI and named S1-0.3;

[0036] S2 and S-nZVI Optimization of Anaerobic Treatment of Dye-Organic Wastewater

[0037] The anaerobic digestion sludge was added to a serum bottle with a capacity of 250 mL and an effective reaction volume of 200 mL, and the concentration of the anaerobic digestion sludge was adjusted to 5 g TS / L. Then, the S-nZVI obtained in step S1 was added to the anaerobic digestion sludge at a dosage of 0.5 g / L, and 150 mL of dye-organic wastewater was introduced. The pH was adjusted to pH=7 by 0.1 mol / L HCl solution, and nitrogen was blown off for 30 minutes, and then placed in a shaker, and the shaker speed was adjusted to 150 rpm, and the temperature was 37°C, and the anaerobic biological treatment was carried out for 12 hours;

[0038] In step S2, the composition of dye-organic wastewater is: methyl orange (MO): 200 mg / L, glucose: 2000 mg / L, KH 2 PO 4 :25mg / L,NH 4 Cl: 100 mg / L, MgCl 2 :20mg / L, CaCl 2 : 30mg / L, EDTA: 5mg / L, FeSO 4 7H 2 O: 2mg / L, ZnSO 4 7H 2 O: 1mg / L, MnCl 2 ·4H 2 O: 3mg / L, H 3 BO 4 :30mg / L,CoCl 2 6H2 O: 20mg / L, CuCl 2 ·2H 2 O: 1mg / L, NiCl 2 6H 2 O: 2mg / L, Na 2 MoO 4 ·2H 2 O: 3mg / L.

[0039] Example 2: Different from Example 1, in step S1, sodium dithionite and ferrous sulfate heptahydrate are in a molar ratio of S:Fe=0.1:1, named S1-0.1.

[0040] Example 3: Different from Example 1, in step S1, sodium dithionite and ferrous sulfate heptahydrate are in a molar ratio of S:Fe=0.5:1, named S1-0.5.

[0041] Example 4: Different from Example 1, in step S1, potassium borohydride with a concentration of 0.4 mol / L is added to the mixed solution by a peristaltic pump at a dropping rate of 8 mL / min, and the dropping time is 18 min. After centrifugation, the supernatant is removed and washed with ultrapure water and 93% ethanol in turn, and sulfur-doped nano-iron particles are obtained after vacuum drying.

[0042] Example 5: Different from Example 1, in step S1, potassium borohydride with a concentration of 0.5 mol / L is added to the mixed solution by a peristaltic pump at a dropping rate of 12 mL / min, and the dropping time is 22 min. After centrifugation, the supernatant is removed and washed with ultrapure water and 97% ethanol in turn, and sulfur-doped nano-iron particles are obtained after vacuum drying.

[0043] Example 6: Different from Example 1, in step S1, the purity of the inert atmosphere is 99%, the stirring speed is 180 rpm, and the stirring time is 25 min.

[0044] Example 7: Different from Example 1, in step S1, the purity of the inert atmosphere is 99.9%, the stirring speed is 220 rpm, and the stirring time is 40 min.

[0045] Example 8: Different from Example 1, in step S1, the vacuum drying method is: placing the washed material in a vacuum drying oven at a temperature of 45°C and drying for 22 hours.

[0046] Example 9: Different from Example 1, in step S1, the vacuum drying method is: placing the washed material in a vacuum drying oven at a temperature of 55°C and drying for 26 hours.

[0047] Example 10: Different from Example 1, in step S1, the centrifugal speed is 5900 rpm and the centrifugal time is 6 min.

[0048] Example 11: Different from Example 1, in step S1, the centrifugal speed is 6100 rpm and the centrifugal time is 10 min.

[0049] Example 12: Different from Example 1, in step S2, the dosage of S-nZVI is 0.4 g / L and the concentration of anaerobic digestion sludge is 4 gTS / L.

[0050] Example 13: Different from Example 1, in step S2, the dosage of S-nZVI is 0.6 g / L and the concentration of anaerobic digestion sludge is 6 gTS / L.

[0051] Example 14: Different from Example 1, in step S2, the rotation speed of the shaking table is 140 rpm and the temperature is 36°C.

[0052] Example 15: Different from Example 1, in step S2, the rotation speed of the shaking table is 160 rpm and the temperature is 38°C.

[0053] Experimental Example: The description of this experimental example is based on the scheme described in Example 1, and is intended to illustrate the practical application effect of the present invention.

[0054] 1. Explore the effects of the composition of optimized materials and the synthesis method of optimized materials on the rapid start-up of the dye-organic wastewater anaerobic co-metabolism system:

[0055] Blank group: Different from Example 1, no optimization material was added.

[0056] Control group 1: Different from Example 1, 0.5 g / L sulfur-doped nano-iron particles were replaced with nano-iron particles and named nZVI. The synthesis of nano-iron was the same as the one-step S-nZVI except that sodium dithionite was not added.

[0057] Control group 2: Different from Example 1, S-nZVI was synthesized by a two-step method. The synthesis method was as follows: in a 99.99% nitrogen atmosphere and a stirring condition of 200 rpm, 0.13 mol / L ferrous sulfate heptahydrate was dissolved in 50 L of ultrapure water, 0.45 mol / L potassium borohydride was slowly added dropwise at a speed of 10 mL / min by a peristaltic pump, and the addition time was 20 min. Then, sodium dithionite was added and reacted for 30 min. The molar ratio of sodium dithionite to ferrous sulfate heptahydrate was S:Fe=0.3:1. The supernatant was removed by centrifugation at 6000 rpm for 8 min, and the mixture was washed with ultrapure water and 95% ethanol in turn. The mixture was dried in a vacuum drying at 50°C for 24 h to obtain sulfur-doped nano-iron particles, named S2-0.3.

[0058] Control group 3: Different from control group 2, the molar ratio of sodium dithionite to ferrous sulfate heptahydrate is S:Fe=0.1:1, named S2-0.1.

[0059] Control group 4: Different from control group 2, the molar ratio of sodium dithionite to ferrous sulfate heptahydrate is S:Fe=0.5:1, named S2-0.5.

[0060] Conclusion: The test results are shown in the attached figure. Figure 1 As shown, at 12h after the start of the reaction, the dye removal rate of each group reached more than 80%, among which the dye removal rate of S1-0.3 was higher than that of other groups, reaching 93.82%;

[0061] For the anaerobic digestion process, during the 184h operation, due to the stress of the dye, the blank group showed obvious acid accumulation and was irreversible, which also led to significant inhibition of COD degradation and methane production, making the anaerobic digestion process unable to proceed smoothly. However, the addition of materials in control groups 1 to 4 and examples 1 to 3 effectively alleviated the acid inhibition, such as Figure 2 As shown in Figure 2, after anaerobic digestion, the VFAs of all material groups were below 100 mg / L, and Figure 3 It can be seen that the COD removal rates of control groups 1 to 4 and examples 1 to 3 are all greater than 80%;

[0062] Depend on Figure 4It can be seen that, except for the blank group, the cumulative methane production of each group gradually increased, and the acid accumulation in the blank group was irreversible, which affected COD degradation and methane production, indicating that the addition of nano-iron material achieved the smooth start of the methanogenesis process; and from the comparison of Control Example 1 and Control Examples 2 to 4, it can be seen that sulfur doping further promoted the production of methane, and the S1-0.3, S1-0.5 and S2-0.3 obtained in Example 1, Example 3 and Control Group 1 were increased by 35.07%, 17.72% and 8.52% respectively compared with the nZVI group. Therefore, in the anaerobic co-metabolism system of dye-organic wastewater, the one-step synthesis and S / Fe of 0.3, that is, the S-nZVI prepared in Example 1, has absolute advantages in promoting dye degradation, alleviating acid inhibition and improving methanogenesis efficiency.

[0063] 2. Study the effects of various parameters on COD removal rate and methane production during the anaerobic treatment of dye-organic wastewater under 184h operation by preparing S-nZVI and optimizing S-nZVI

[0064] Table 1 Effect of the treatment methods of Example 1, Example 4 to Example 15 on COD removal rate and methane yield

[0065]

[0066] Conclusion: From the comparison of Example 1 and Example 4 to Example 15, it can be obtained that the COD removal effect and methane efficiency achieved by anaerobic treatment of dye-organic wastewater under 184h operation state under the conditions of potassium borohydride addition parameters that are too low or too high within the specified range of this application, inert atmosphere purity, stirring parameters, drying temperature and centrifugation parameters are slightly different from those in Example 1. Therefore, from an economic perspective, Example 1 is selected as the optimal solution.

Claims

1. A method for quickly starting a dye-organic wastewater anaerobic cometabolism system based on S-nZVI, characterized in that: The following steps are involved: S1. Preparation of S-nZVI In an inert atmosphere, sodium dithionite and ferrous sulfate heptahydrate with a concentration of 0.1 to 0.15 mol / L are dissolved in ultrapure water at a molar ratio of S:Fe=(0.1 to 0.5):1, and stirred to obtain a mixed solution. Then, potassium borohydride with a concentration of 0.4 to 0.5 mol / L is added dropwise to the mixed solution at a dropping rate of 8 to 12 mL / min by a peristaltic pump for 18 to 22 min. After centrifugation, the supernatant is removed and washed with ultrapure water and ethanol in turn. After vacuum drying, sulfur-doped nano-iron particles are obtained, which are recorded as S-nZVI. S2, S-nZVI optimize the anaerobic treatment of dye-organic wastewater The anaerobic digestion sludge is added to the serum bottle so that the concentration of the anaerobic digestion sludge is 4-6 gTS / L, and then the S-nZVI obtained in step S1 is added to the anaerobic digestion sludge in an amount of 0.4-0.6 g / L, and 120-180 mL of dye-organic wastewater is introduced, and then the pH is adjusted to pH=6.8-7.2 by a pH regulator. After nitrogen stripping for 25-35 minutes, it is placed in a shaker and anaerobic biological treatment is carried out for 10-14 hours.

2. The method for quickly starting the dye-organic wastewater anaerobic cometabolism system based on S-nZVI as claimed in claim 1, characterized in that: In step S1, the purity of the inert atmosphere is 99-99.9%, the stirring speed is 180-220 rpm, and the stirring time is 25-40 min.

3. The method for quickly starting the dye-organic wastewater anaerobic cometabolism system based on S-nZVI as claimed in claim 1, characterized in that: The vacuum drying method is: putting the washed material into a vacuum drying oven at a temperature of 45 to 55° C. and drying for 22 to 26 hours.

4. The method for quickly starting the dye-organic wastewater anaerobic cometabolism system based on S-nZVI as claimed in claim 1, characterized in that: In step S1, the centrifugal speed is 5900-6100 rpm, and the centrifugal time is 6-10 min.

5. The method for quickly starting the dye-organic wastewater anaerobic cometabolism system based on S-nZVI as claimed in claim 1, characterized in that: In step S1, the mass concentration of ethanol is 93-97%.

6. The method for quickly starting the dye-organic wastewater anaerobic cometabolism system based on S-nZVI as claimed in claim 1, characterized in that: In step S2, the composition of the dye-organic wastewater is: methyl orange (MO): 200 mg / L, glucose: 2000 mg / L, KH2PO4: 25 mg / L, NH4Cl: 100 mg / L, MgCl2: 20 mg / L, CaCl2: 30 mg / L, EDTA: 5 mg / L, FeSO4·7H2O: 2 mg / L, ZnSO4·7H2O: 1 mg / L, MnCl2·4H2O: 3 mg / L, H3BO4: 30 mg / L, CoCl2·6H2O: 20 mg / L, CuCl2·2H2O: 1 mg / L, NiCl2·6H2O: 2 mg / L, Na2MoO4·2H2O: 3 mg / L.

7. The method for quickly starting the dye-organic wastewater anaerobic cometabolism system based on S-nZVI as claimed in claim 1, characterized in that: In step S2, the rotation speed of the shaking table is 140-160 rpm and the temperature is 36-38°C.

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