Method for realizing long-acting control of sulfate reducing bacteria by inhibiting hydrogen metabolism and application

Abstract

The invention discloses a method for realizing long-acting control of sulfate reducing bacteria by inhibiting hydrogen metabolism and application, and belongs to the technical field of microorganism prevention and control. According to the method, polysulfide is added into a liquid microenvironment where sulfate reducing bacteria survive, and the method is suitable for the liquid environment where biological acidification / corrosion inhibitors such as sulfate analogues and nitrate exist and can be applied to biological acidification / biological corrosion control in the environments of oil reservoirs, produced water and the like. The method provided by the invention overcomes the defects of existing technologies of controlling biological acidification by adding nitrate and sulfate analogues and the like, and realizes effective inhibition of metabolic activity and species abundance of sulfate reducing bacteria in environments with high organic matter electron donors and low sulfate electron acceptors; and the progress of the oil reservoir biological acidification and biological corrosion control technology is promoted in principle.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of microbial prevention and control, and particularly relates to a method for long-term control of sulfate-reducing bacteria by inhibiting hydrogen metabolism and application thereof in the control of biological acidification / biological corrosion in oil reservoirs, produced water and the like environments. BACKGROUND

[0002] Sulfate-reducing bacteria are a kind of facultative anaerobic microorganisms that use sulfate as an electron acceptor. A few groups can also grow under aerobic conditions. They not only play a key role in the global carbon, nitrogen and sulfur geochemical cycle, but also play an irreplaceable role in the field of pollution control. Microbial species are diverse in oil reservoir or produced water environments, and biological acidification or biological corrosion caused by sulfate-reducing bacteria has become a common problem in oilfield industrial systems, resulting in economic losses of up to 90 billion US dollars per year. A key mechanism by which sulfate-reducing bacteria accelerate metal corrosion is that hydrogen sulfide produced by sulfate-reducing bacteria during sulfate reduction can promote chemical corrosion of metals, and sulfate-reducing bacteria further utilize hydrogen released by metal chemical corrosion, thereby accelerating the corrosion of metals. It is reported that biological acidification or biological corrosion has occurred in 80% of traditional oil reservoirs and 40% of gas reservoirs worldwide.

[0003] At present, a variety of methods and technologies for controlling biological acidification have been developed, such as adding sulfate analogs (sulfate analog oxyanions), nitrate, perchlorate, biocides, bacteriophages and the like. Biological biocides can non-specifically and broadly kill a variety of endogenous microorganisms in water. However, the widespread use of biological biocides can cause biological drug resistance, and seriously threaten the successful implementation of the biological oil displacement technology which uses endogenous microorganisms as a strain resource library.

[0004] Sulfate analogs are a kind of inorganic salts similar in structure and molecules to sulfate, such as selenate, monofluorophosphate, tungstate, molybdate, arsenate and the like. They can act as competitive substrates for sulfate adenosine transferase, and thus competitively inhibit the activity of sulfate reduction ( Figure 1 ). Nitrate and perchlorate are widely used as biological competitive inhibitors to inhibit the sulfate reduction activity of sulfate-reducing bacteria. They can activate endogenous nitrate-reducing bacteria or perchlorate-reducing bacteria, which can compete with sulfate-reducing bacteria for available electron donors, and also produce metabolic intermediates such as nitrite, thereby inhibiting the activity of sulfite reductase ( Figure 1 ). The intrinsic mechanism of sulfate analogs and nitrate substances for inhibiting the activity of sulfate-reducing bacteria is to inhibit the intracellular electron transport chain of sulfate reduction, thereby creating a microenvironment lacking an electron acceptor or lacking an electron donor for sulfate-reducing bacteria ( Figure 1). Although this strategy can prevent the reduction of sulfate, sulfate-reducing bacteria can still maintain considerable metabolic activity and species abundance in the aquatic environment by fermentation or interspecies electron transfer. High abundance of sulfate-reducing bacteria is still a huge internal factor for the occurrence of oil reservoir bioacidification or biocorrosion.

[0005] The oil reservoir environment is a typical environment with high organic electron donor and low sulfate electron acceptor. When sulfate-reducing bacteria are inhibited by nitrate and sulfate analogues, the sulfate-reducing bacteria will actually enter a metabolic process of sulfate electron acceptor starvation, that is, the sulfate-reducing bacteria enter a state of fermentation growth using organic matter. At this time, the cells will release a large amount of hydrogen by incomplete oxidation of organic matter to adjust the intracellular redox balance, and some groups of sulfate-reducing bacteria can even absorb part of the hydrogen while releasing hydrogen, which can couple the intracellular energy production of sulfate-reducing bacteria. Therefore, how to break the intracellular redox balance and energy production pathway of sulfate-reducing bacteria under this condition will be the key to realizing long-term bioacidification / biocorrosion control. SUMMARY

[0006] The purpose of the present application is to solve the problem that the prior art cannot completely control the metabolic activity and species abundance of sulfate-reducing bacteria by adding a bioacidification / corrosion inhibitor that inhibits the enzyme activity related to the sulfate reduction metabolic pathway of sulfate-reducing bacteria, and to provide a new method for long-term control of sulfate-reducing bacteria by inhibiting hydrogen metabolism.

[0007] The technical scheme of the present application is described in detail as follows: In a first aspect, the present application provides a method for long-term control of sulfate-reducing bacteria by inhibiting hydrogen metabolism, which is suitable for a liquid environment in which a bioacidification / corrosion inhibitor has already been added. The bioacidification / corrosion inhibitor functions by inhibiting the enzyme activity related to the sulfate reduction metabolic pathway of sulfate-reducing bacteria. The method is to add polysulfide to the liquid environment for long-term control.

[0008] In the present application, the bioacidification / corrosion inhibitor refers to a preparation that has been disclosed for treating bioacidification and / or biocorrosion. The enzyme related to the sulfate reduction metabolic pathway is an enzyme that participates in and affects the smooth progress of the sulfate reduction metabolic pathway, including sulfate adenylyltransferase, adenylylsulfate reductase, and sulfite reductase. The sulfate reduction metabolic pathway of sulfate-reducing bacteria is that sulfate adenylyltransferase activates sulfate (SO4 2- ) to generate adenylylsulfate (APS), which is then reduced to sulfite (SO3 2- ) by adenylylsulfate reductase, and SO3 2- is further reduced to sulfide (S 2- ) by sulfite reductase.

[0009] The polysulfide is a compound containing polysulfide ions, including polysulfide alkali metals (such as sodium polysulfide, potassium polysulfide, lithium polysulfide) obtained by reacting alkali metal sulfide with sulfur, polysulfide hydrogen obtained by reacting ammonium sulfide with sulfur, and polysulfide alkali metals (such as calcium polysulfide, magnesium polysulfide, etc.) obtained by reacting non-radioactive alkaline earth metals with sulfur. The polysulfide can be directly purchased as a commercial industrial chemical, or can be prepared by oneself.

[0010] Preferably, in the above method, the polysulfide includes: Na2S x and / or K2S x x is the number of sulfur atoms, and the value of x ranges from 1 to 18.

[0011] Optionally or preferably, in the above method, the polysulfide is added in the form of an aqueous solution, and the concentration of the polysulfide aqueous solution ranges from 1 to 5 mol / L.

[0012] Optionally or preferably, in the above method, the amount of the polysulfide added is that the volume ratio of the polysulfide aqueous solution to the liquid in which the sulfate-reducing bacteria survive is 1:600.

[0013] Optionally or preferably, in the above method, the polysulfide is prepared by reacting Na2S•9H2O crystals, elemental S 0 and ultrapure water in a molar ratio of 1:1:9 under anaerobic, room temperature and shaking conditions until the elemental sulfur is completely dissolved.

[0014] Optionally or preferably, in the above method, the biological acidification / corrosion inhibitor includes sulfate analogs and / or nitrate. The mechanism of action of the sulfate analogs and the nitrate is the same, that is, by inhibiting the enzyme activity related to the sulfate reduction metabolic pathway to interfere with the smooth progress of the metabolic pathway to prevent the growth and reproduction of sulfate-reducing bacteria.

[0015] Optionally or preferably, in the above method, the sulfate analogs include one or more of selenate, monofluorophosphate, tungstate, molybdate, and arsenate.

[0016] In a second aspect, the present application provides the use of any of the above-mentioned methods in the biological acidification and biological corrosion treatment of an anaerobic water body of an oil reservoir.

[0017] In a third aspect, the present application provides the use of any of the above-mentioned methods in the biological acidification and biological corrosion treatment of an anaerobic water body of produced water.

[0018] Compared with the prior art, the present application has the following beneficial effects: The method provided by the application is adding polysulfides to a liquid microenvironment to which a biological acidification / corrosion inhibitor has been added, by controlling the intracellular hydrogen metabolic activity (including hydrogen production and hydrogen absorption) of sulfate-reducing bacteria and the inter-species electron transfer activity of the colony, and inhibiting the energy production of the sulfate-reducing bacteria under the condition, thereby inhibiting the intracellular energy metabolic activity of the sulfate-reducing bacteria, and finally achieving the decrease of the inter-species electron transfer activity and the species abundance of the sulfate-reducing bacteria.

[0019] The method of the application overcomes the shortcomings of the conventional biological acidification control method, i.e. adding a biological acidification / corrosion inhibitor which functions by inhibiting the enzyme activity related to the sulfate-reduction metabolic pathway of sulfate-reducing bacteria, which is only used to inhibit the intracellular electron transfer process of sulfate reduction, and cannot inhibit the metabolic activity and species abundance of sulfate-reducing bacteria, and achieves effective inhibition of the metabolic activity and species abundance of sulfate-reducing bacteria under the environment of high organic electron donor and low sulfate electron acceptor (i.e. the environment of insufficient sulfate electron acceptor), and promotes the progress of the oil reservoir biological acidification and biological corrosion control technology in principle. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 A schematic diagram of the inhibition mechanism of the conventional biological acidification / corrosion inhibitor (including sulfate analogues and nitrate) on the sulfate-reduction metabolic pathway of sulfate-reducing bacteria.

[0021] Figure 2 The headspace hydrogen content of serum bottles monitored at different times in Example 3, which reflects the hydrogen production activity of the sulfate-reducing bacteria complex in the oil reservoir when lacking sulfate electron acceptor, polysulfides(+) represents the experimental group with added polysulfides, and polysulfides(-) represents the control group without added polysulfides.

[0022] Figure 3 The ATP content monitoring results of the experimental group and the control group in Example 3, which reflect the influence of polysulfides on the ATP production of the sulfate-reducing bacteria complex when lacking sulfate electron acceptor, polysulfides(+) represents the experimental group with added polysulfides, and polysulfides(-) represents the control group without added polysulfides.

[0023] Figure 4 The headspace hydrogen content monitoring results of the experimental group and the control group in Example 4, which reflect the influence of polysulfides on the hydrogen consumption activity of sulfate-reducing bacteria using hydrogen as the electron donor and sulfate as the electron acceptor, polysulfides(+) represents the experimental group with added polysulfides, and polysulfides(-) represents the control group without added polysulfides.

[0024] Figure 5For the changes in the species abundance of the common sulfate-reducing bacteria in the community species abundance table in the experimental groups and the control groups statistically analyzed in Example 5, polysulfides(+) indicates the experimental group to which polysulfides were added, and polysulfides(-) indicates the control group to which polysulfides were not added. DETAILED DESCRIPTION

[0025] For the purpose of better understanding the technical scheme of the present application, the present application will be described clearly and completely below in conjunction with the embodiments and drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative work should fall within the protection scope of the present application. The instruments and reagents used in the embodiments are all from commercial channels unless otherwise specified.

[0026] Example 1 Preparation of polysulfides A preferred embodiment of artificially synthesized polysulfides is as follows: Na2S•9H2O crystals, elemental S 0 and ultrapure water are reacted in a molar ratio of 1:1:9 under anaerobic, room temperature and shaking conditions for 1-2 days until the elemental sulfur is completely dissolved. After complete reaction, a dark orange polysulfide mixture (main component is Na2S x ) is obtained.

[0027] Example 2 Obtaining of oil reservoir sulfate-reducing bacteria complex (1) Preparation of anaerobic inorganic salt medium The composition of the anaerobic inorganic salt medium per liter is: 1.0 g KH2PO4, 1.0 g K2HPO4, 1.0 g NH4Cl, 0.05 g MgCl2, 0.006 g CaCl2, 0.006 g FeCl2, 0.01 g Na2O4S2 (sodium dithionite), and 1 mL of trace element solution, and the rest is water. The pH of the anaerobic inorganic salt medium is adjusted to 7.0 by 1 M HCl and 1 M NaOH.

[0028] The trace element solution per liter contains: 0.014 g H3BO3, 0.99 g MnCl2·4H2O, 0.25 g CuSO4·5H2O, 0.43 g ZnSO4·7H2O, 0.19 g NiCl2·6H2O, 0.22 g Na2MoO4·2H2O, 0.24 g CoCl2·6H2O, 0.21 g NaSeO4·10H2O, and the rest is water.

[0029] (2) Enrichment and culture of sulfate-reducing bacteria community Take 100 mL of reservoir produced fluid and inoculate it into a serum bottle containing 200 mL of anaerobic inorganic salt culture medium. Incubate for 7 days in a light-proof constant temperature incubator at 40℃ and 140 rpm to obtain the culture complex.

[0030] Then, 20 mL of the mixture was taken from the culture complex and inoculated into a new serum bottle containing 300 mL of anaerobic inorganic salt medium with an effective volume of 500 mL, and the reservoir sulfate-reducing bacteria were rapidly enriched in a sequencing batch operation mode.

[0031] The sequencing batch reactor (SBR) cycle lasts approximately 3 days, including: water inlet (10 min), reaction (2.8 days), settling (4 hours), and drainage (10 min). During the water inlet phase, 250 mL of anaerobic inorganic salt culture medium is introduced into the anaerobic serum bottle. During the drainage phase, 250 mL of fermentation broth is extracted from the top of the anaerobic serum bottle using a syringe. This process is repeated continuously for one month to enrich the reservoir sulfate-reducing bacteria complex.

[0032] The obtained reservoir sulfate-reducing bacteria complex is not a single sulfate-reducing bacteria species, but a complex sulfate-reducing community. This community is rich in species and can simulate various physiological states of sulfate-reducing bacteria in the reservoir environment.

[0033] Example 3: Effects of polysulfides on hydrogen and ATP production by sulfate-reducing bacteria in the absence of sulfate electron acceptors. Because the reservoir environment is typically characterized by high organic electron donors and low sulfate electron acceptors, the addition of conventional biological acidification / corrosion inhibitors (whose mechanism of action is to inhibit the sulfate reduction metabolic pathway) causes sulfate-reducing bacteria to enter a metabolic state of sulfate electron acceptor starvation. In other words, sulfate-reducing bacteria enter a metabolic microenvironment lacking both sulfate electron acceptors and electron donors. Figure 1 ).

[0034] This is because the added biological acidification / corrosion inhibitors, such as sulfate analogs (tungstates, selenates, arsenates, etc.), which inhibit the smooth progress of the sulfate reduction metabolic pathway, can non-specifically bind to the active site of sulfate adenosine sulfate transferase in sulfate-reducing bacteria. Sulfate adenosine sulfate transferase is the first step in sulfate reduction, and its main function is to activate sulfate. The addition of sulfate analogs inevitably leads to a lack of sulfate electron acceptors in the metabolism of sulfate-reducing bacteria. Figure 1). The addition of nitrate will activate the nitrate-reducing bacteria in the oil reservoir, and the nitrate-reducing bacteria will multiply and reduce the nitrate. This process not only consumes a large amount of available electron donors for the sulfate-reducing bacteria, but also accumulates nitrite, which can significantly inhibit the activity of sulfite reductase. Therefore, the addition of these two traditional biological acidification / corrosion inhibitors will cause the sulfate-reducing bacteria to enter a metabolic microenvironment that lacks sulfate electron acceptors and lacks electron donors.

[0035] When the sulfate-reducing bacteria encounter the above metabolic microenvironment, they turn into a state of fermentative growth using organic matter. The fermentation of organic matter by sulfate-reducing bacteria produces a large amount of reducing power (such as NADH, NADPH, and reduced ferredoxin), and at this time the cell will release a large amount of hydrogen by incomplete oxidation of organic matter to regulate the intracellular redox balance. Some groups of sulfate-reducing bacteria can even absorb part of the hydrogen while releasing hydrogen, and this metabolic activity can couple the intracellular energy production of sulfate-reducing bacteria. Our research found that hydrogen metabolism is very common when sulfate-reducing bacteria respond to a lack of electron acceptors.

[0036] In view of the fact that hydrogen release is considered an important way for microorganisms to balance intracellular redox levels under conditions of electron acceptor starvation, in order to simulate a sulfate-starved environment, this embodiment simulates the hydrogen-producing metabolic activity of sulfate-reducing bacteria in an inorganic salt medium without sulfate (i.e., lacking sulfate electron acceptors) to verify that polysulfides can inhibit the production of hydrogen and ATP by sulfate-reducing bacteria when there is a lack of electron acceptors.

[0037] The anaerobic inorganic salt medium in Example 2 was prepared, and sodium lactate was added at a standard concentration of 4.0 g / L to form a first inorganic salt medium without sulfate electron acceptors and containing only sodium lactate as an electron donor (carbon source).

[0038] Although the first inorganic salt medium simulates a liquid environment with existing biological acidification / corrosion inhibitors, no sulfate analogs or nitrate are added to the medium. The main reason is that sulfate analogs and nitrate may act as electron acceptors for other microorganisms contained in the enriched sulfate-reducing bacteria complex, and these microorganisms that can reduce sulfate analogs and nitrate can also use hydrogen produced by sulfate-reducing bacteria, thereby interfering with the accuracy of the experimental results.

[0039] The obtained sulfate-reducing bacteria complex was aliquoted into 6 serum bottles containing 300 mL of the first inorganic salt medium with an effective volume of 500 mL. 0.5 mL of polysulfide solution prepared in Example 1 was added to 3 of the serum bottles as the experimental group at a volume ratio of polysulfide solution to the first inorganic salt medium of 1:600. The other 3 serum bottles were not added with polysulfide as the control group. The 6 anaerobic serum bottles were placed in a constant temperature incubator at 40°C and 140 rpm for continuous culture for several days, and the headspace hydrogen content of the serum bottles was continuously monitored. At the first day of culture, the ATP content of the bacteria was measured. The ATP content of each sample was normalized according to the total protein content of the bacteria in the sample.

[0040] The hydrogen monitoring results are shown in Figure 2 , which shows the hydrogen production activity of the oil reservoir sulfate-reducing bacteria complex in the absence of sulfate electron acceptors in the presence of polysulfides. As can be seen from Figure 2 , polysulfides completely inhibited the hydrogen production activity of the experimental group (light line, polysulfides(+)) within 100 hours, while the control group (dark line, polysulfides(-)) without the addition of polysulfides showed active hydrogen production activity.

[0041] The ATP content monitoring results are shown in Figure 3 , and the addition of polysulfides also significantly inhibited the ATP synthesis ability of the oil reservoir sulfate-reducing bacteria complex. As can be seen, the ATP production of the experimental group polysulfides(+) with the addition of polysulfides was significantly inhibited, while the ATP production of the control group polysulfides(-) without the addition of polysulfides was very high.

[0042] In summary, under laboratory conditions, polysulfides have a significant inhibitory effect on the hydrogen production ability of sulfate-reducing bacteria in the absence of sulfate electron acceptors (i.e. in the presence of sulfate analogs and nitrate, which are biological acidification / corrosion inhibitors) and in the presence of sufficient carbon source. In this embodiment, 0.5 mL of polysulfide solution (prepared in Example 1) added at a volume ratio of 1:600 can completely inhibit the hydrogen production activity of sulfate-reducing bacteria for up to 8 days. Due to the difference in species abundance of the bacterial community, the inhibition time of polysulfides will fluctuate.

[0043] Example 4 Inhibition of hydrogen absorption by sulfate-reducing bacteria in the presence of sulfate but in the absence of carbon source by polysulfides In the presence of conventional bioacidification / corrosion inhibitors, sulfate-reducing bacteria in an oil reservoir environment with high organic electron donors will essentially enter a metabolic state of sulfate electron acceptor starvation. In this case, most microorganisms will enter a state of fermentation growth using organic matter to produce hydrogen to balance the intracellular redox level, and some microorganisms can produce hydrogen while anaerobically absorbing hydrogen. The hydrogen-producing hydrogenase occurs in the cytoplasm, and the hydrogen-consuming hydrogenase occurs in the periplasmic space. The simultaneous production and consumption of hydrogen during the fermentation of organic matter by sulfate-reducing bacteria actually promotes the energy metabolism of the bacteria. Therefore, to interfere with the energy metabolism of sulfate-reducing bacteria, in addition to investigating the inhibition of hydrogen production by polysulfides in Example 3, we also investigated the inhibition of hydrogen consumption by polysulfides in Example 4. In a real oil reservoir environment with the addition of bioacidification / corrosion inhibitors, hydrogen is produced during metal corrosion. When no other organic carbon source is available, sulfate-reducing bacteria can use the hydrogen produced by metal corrosion to grow, thereby accelerating metal corrosion. This key condition is also considered in this Example 4.

[0044] This example simulates the effect of polysulfides on the anaerobic absorption of hydrogen by sulfate-reducing bacteria in the presence of sulfate.

[0045] The anaerobic inorganic salt medium in Example 2 was prepared, and sodium sulfate was added to a final concentration of 3.0 g / L to form a second inorganic salt medium containing only sodium sulfate as an electron acceptor without sodium lactate as an electron donor.

[0046] To demonstrate the inhibitory effect of polysulfides on the absorption of hydrogen by sulfate-reducing bacteria, the sulfate-reducing bacteria complex obtained in (1) was aliquoted and transferred to six serum bottles containing 300 mL of anaerobic inorganic salt medium containing sodium sulfate, with an effective volume of 500 mL, to create conditions containing sulfate but lacking a carbon source.

[0047] Three serum bottles were randomly selected and added with 0.5 mL of polysulfide solution prepared in Example 1 at a volume ratio of 1:600 of polysulfide solution to second inorganic salt medium as the experimental group; the other three serum bottles were not added with polysulfides as the control group. Then, a mixture of H2, CO2, and N2 at a volume ratio of 40:20:40 was introduced into the headspace of the six anaerobic serum bottles at a pressure of 0.2 MPa. The six anaerobic serum bottles were placed in a constant-temperature incubator at 40°C and 140 rpm for continuous culture for several days. The hydrogen content in the headspace of the serum bottles was continuously monitored, and a decrease in hydrogen content indicated high hydrogen absorption activity of sulfate-reducing bacteria.

[0048] The hydrogen content monitoring results are shown in Table 1. Figure 4 , Figure 4The effect of polysulfides on the hydrogen uptake activity of the oil reservoir sulfate-reducing bacteria consortium with hydrogen as the electron donor and sulfate as the electron acceptor was demonstrated. Figure 4 As can be seen from the results, the addition of polysulfides in the experimental group (light line, polysulfides (+)) significantly inhibited the hydrogen uptake activity of the oil reservoir sulfate-reducing bacteria consortium with hydrogen as the electron donor and sulfate as the electron acceptor.

[0049] The experimental results of Example 3 and Example 4 show that the addition of polysulfides can inhibit the hydrogen metabolism activity (including hydrogen production and hydrogen consumption) of sulfate-reducing bacteria in the presence of conventional biological acidification / corrosion inhibitors.

[0050] Example 5 Effect of polysulfides on the species abundance of oil reservoir sulfate-reducing bacteria in the absence of sulfate electron acceptor The enrichment and culture of the sulfate-reducing bacteria group were the same as in Example 2. The culture medium used was the first inorganic salt culture medium of Example 3, containing sodium lactate, and not containing sulfate electron acceptor.

[0051] Detection of the effect of polysulfides on the relative abundance of sulfate-reducing bacteria species: The sulfate-reducing bacteria consortium obtained by enrichment was aliquoted and transferred to 6 serum bottles containing 300 mL of the first inorganic salt culture medium with an effective volume of 500 mL. 0.5 mL of the polysulfide solution prepared in Example 1 was added to 3 of the serum bottles as the experimental group at a volume ratio of polysulfide solution to first inorganic salt culture medium of 1:600; the other 3 serum bottles were not added with polysulfides as the control group. The 6 anaerobic serum bottles were placed in a constant temperature incubator at 40°C, 140 rpm for continuous culture for several days, and the relative abundance of sulfate-reducing bacteria species in each serum bottle was continuously monitored.

[0052] The relative abundance of sulfate-reducing bacteria species was detected by 16S rRNA amplicon technology. The specific method is as follows: an appropriate amount of bacterial sample was taken, the total DNA of microorganisms was extracted by using a bacterial DNA genome extraction kit, and then primers 515 F (5'-GTGCCAGCMGCCGCGGTAA-3') and 907 R (5'-CCGTCAATTCMTTTRAGTTT-3') were used for amplification.

[0053] The amplification program is as follows: pre-denaturation at 95°C for 2 min, 32 cycles of denaturation at 95°C for 15 s, annealing at 53°C for 30 s, and extension at 72°C for 15 s, and stable extension at 72°C for 5 min.

[0054] PCR reaction system: 5×TransStart FastPfu buffer 4 μL, 2.5 mM dNTPs 2 μL, upstream primer (5 μM) 0.8 μL, downstream primer (5 μM) 0.8 μL, TransStart FastPfu DNA polymerase 0.4 μL, template DNA 10 ng, ddH2O to 20 μL.

[0055] Library construction was performed using NEXTflexTM Rapid DNA-Seq Kit (Bioo Scientific, USA). 16S gene sequencing was performed using the Miseq PE250 sequencing platform of Illumina Company. The raw sequences obtained by sequencing were subjected to quality control, and then kraken2 software was used for species annotation (the database used was 16S_Silva138_20200326). The species abundance of common sulfate-reducing bacteria (such as Desulfobulbus sp.) in the community species abundance table was counted. Desulfovibrio

[0056] The statistical results are shown in Figure 5 , Figure 5 The figure shows the change of the species abundance of common sulfate-reducing bacteria in the community species abundance table of the experimental group (light line, polysulfides(+)) and the control group (dark line, polysulfides(-)) with the addition of polysulfides over time. Combined with Figure 1 , it can be seen that during the period when the hydrogen production activity of sulfate-reducing bacteria is inhibited by polysulfides (0-168h), the addition of polysulfides can significantly reduce the species abundance of sulfate-reducing bacteria in the absence of sulfate electron acceptors.

[0057] In summary, Examples 3-5 simulate the liquid environment under the condition of adding conventional biological acidification / corrosion inhibitors such as nitrate and sulfate analogs. Under this environment, sulfate-reducing bacteria enter a metabolic microenvironment lacking sulfate electron acceptors and lacking electron donors, and turn to a fermentation growth state using organic matter in order to continue to survive. This is also the reason why conventional biological acidification / corrosion inhibitors cannot achieve long-term control. The addition of polysulfides in the present application can effectively inhibit this situation, thereby achieving long-term control of sulfate-reducing bacteria.

[0058] In this paper, specific examples are used to elaborate the inventive concept in detail. The above examples are only used to help understand the core idea of the present application. It should be noted that any obvious modifications, equivalent replacements or other improvements made by those skilled in the art without departing from the inventive concept should be included in the protection scope of the present application.​

Claims

1. A method for long-term control of sulfate-reducing bacteria by inhibiting hydrogen metabolism, suitable for liquid environments where a bioacidification / corrosion inhibitor is already present, characterized in that, The polysulfide is added to the liquid environment for long-term control; the biological acidification / corrosion inhibitor plays a role by inhibiting the enzyme activity related to the sulfate reduction metabolic pathway of sulfate-reducing bacteria.

2. The method of claim 1, wherein, The polysulfide includes Na2S x and / or K2S x x is the number of sulfur atoms, and x has a value in the range of 1 to 18.

3. The method of claim 2, wherein, The polysulfide is added in the form of an aqueous solution, and the concentration of the added polysulfide aqueous solution ranges from 1 to 5 mol / L.

4. The method of claim 3, wherein, The polysulfide is added in an amount such that the volume ratio of the polysulfide aqueous solution to the liquid in which the sulfate-reducing bacteria survive is 1:

600.

5. The method of claim 1, wherein, The polysulfide is prepared by reacting Na2S•9H2O crystals, elemental S 0 and ultrapure water in a molar ratio of 1:1:9 under anaerobic, room temperature and shaking conditions until the elemental sulfur is completely dissolved.

6. The method of claim 1, wherein, The biological acidification / corrosion inhibitor includes a sulfate analog and / or a nitrate.

7. The method of claim 6, wherein, The sulfate analog includes one or more of selenate, monofluorophosphate, tungstate, molybdate, and arsenate.

8. Use of the method of any one of claims 1 to 7 in the treatment of biological acidification and biological corrosion of an anaerobic water body in an oil reservoir.

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