Oil and gas field produced water gas-liquid two-phase biological desulfurization treatment process

Abstract

The invention relates to the technical field of sewage treatment, and discloses an oil and gas field produced water gas-liquid two-phase biological desulfurization treatment process which comprises the following steps: S1, adding a biological activator, namely adding 10-250g of the biological activator containing glucose and nitrate (in a mass ratio of (1-5): 1) into each cubic meter of produced water into the oil and gas field produced water. And S2, competitive inhibition of microorganisms: the activator promotes reproduction of native anaerobic microorganisms (mainly denitrifying bacteria DNB), and the native anaerobic microorganisms and sulfate reducing bacteria (SRB) contend for space and nutrient substrates, so that the growth and reproduction of the SRB are inhibited, and the inhibition rate reaches 85% or above. S3, carrying out catalytic conversion by virtue of a biological enzyme, exchanging oxygen-containing groups with Scharges and electrons in the sewage by virtue of the action of the biological enzyme, converting Sinto SO, and reducing the content of sulfides in produced liquid and associated gas. The process is remarkable in cost benefit, does not need complex equipment and high medicament investment, reduces the operation, maintenance and corrosion cost, prolongs the service life of the equipment, and indirectly saves the cost.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, in particular to a gas-liquid two-phase biological desulfurization treatment process for produced water from an oil and gas field. Background Art

[0002] Sulfide is widely present in oilfield produced water, which brings about a series of complex problems such as serious corrosion, scaling, sulfate-reducing bacteria (SRB) reproduction, and difficulty in treatment. Sulfide mainly comes from the following four aspects: first, it exists in the formation and is brought to the surface with oil extraction; second, it is produced during the production process; third, it is produced by the degradation of organic matter; fourth, the reduction effect of SRB converts SO in water into 4 ²⁻ is reduced to S²⁻. Sulfide in oilfield wastewater is mainly produced by SRB reducing sulfate.

[0003] At present, there are many methods for treating sulfur-containing wastewater at home and abroad, such as air oxidation, chemical oxidation, biological method, etc. The oxidation ability of air is relatively weak. In order to improve the oxidation effect, the oxidation process needs to be carried out under specific conditions, such as high temperature, high pressure or the use of catalysts; the chemical method refers to the use of chemical agents to react with sulfides in sewage to generate precipitation, gas or other products, thereby achieving the purpose of desulfurization, which is easy to cause secondary pollution. The gas, liquid and precipitation products produced after treatment need to be reprocessed; the biological method mainly uses microorganisms or the enzymes they contain to catalyze sulfur-containing compounds to remove sulfur-containing compounds. The advantages are less pollution, low energy consumption, high efficiency and less infrastructure investment.

[0004] Therefore, desulfurization of sulfur-containing wastewater can reduce environmental pollution on the one hand, and make full use of oilfield wastewater for reinjection on the other hand, reduce the demand for oil well reinjection water, save production costs, and reduce water resource consumption, which has great economic, environmental and social benefits. However, the existing treatment process still has technical problems such as high cost of producing water, easy to produce secondary pollution, and large application limitations that need to be solved urgently. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the shortcomings of the existing technology, the present invention provides a gas-liquid two-phase biological desulfurization treatment process for oil and gas field produced water, which has the advantages of achieving efficient, environmentally friendly and economical desulfurization treatment goals, and solves the problems of high cost of producing water treatment, secondary pollution and application limitations in the existing treatment process.

[0007] (II) Technical solution

[0008] In order to achieve the above-mentioned purpose of efficient, environmentally friendly and economical desulfurization treatment, the present invention provides the following technical solutions:

[0009] A two-phase biological desulfurization process for produced water, gas and liquid in oil and gas fields, comprising the following steps:

[0010] S1. Addition of bioactivator

[0011] Adding a first bioactivator to produced water from an oil and gas field, wherein the first bioactivator is composed of glucose and nitrate, wherein the mass ratio of glucose to nitrate is (1-5):1, and the addition amount is 10-250 grams of the first bioactivator per cubic meter of produced water;

[0012] S2. Microbial competitive inhibition

[0013] The addition of the second biological activator promotes the massive reproduction of native anaerobic microorganisms in the produced water of the oil field. The native anaerobic microorganisms are mainly denitrifying bacteria DNB. The native anaerobic microorganisms compete with sulfate-reducing bacteria (SRB) for living space and nutrient substrates, which inhibits the growth and reproduction of SRB, and the inhibition rate reaches more than 85%;

[0014] S3, enzyme-catalyzed conversion

[0015] Under the action of biological enzymes, the charge and electron exchange between oxygen-containing groups in sewage and S²⁻ is promoted, so that S²⁻ is converted into SO 4 ²⁻, thereby reducing S²⁻ in the produced fluid and H in the associated gas 2 S, after treatment, the S²⁻ content in the produced fluid is reduced to 0-5 mg / L, and the H 2 The S content is reduced by more than 85% or below 20 mg / m3.

[0016] Preferably, in step S1, the intermittent dosing process of the oil well casing also includes the following operations:

[0017] (1) Equipment preparation operation: prepare a mobile dosing pump truck and equip it with a second plunger pump, connect the mobile pump truck and the first plunger pump, and check the sealing and pressure system of the equipment to ensure the normal operation of the equipment;

[0018] (2) Bioactivator loading operation: according to the composition and dosage requirements of the first bioactivator in claim 1, the bioactivator is prepared into a solution and loaded into the storage tank of the mobile pump truck;

[0019] (3) Dosing parameter setting operation: Set the dosing cycle of the first plunger pump to once every 2-5 days, and determine the dosing dosage of each time to be 25-100 liters according to the oil well produced liquid volume and sulfur content. Start the first plunger pump to inject the first bioactivator (1-1) solution into the wellhead casing of the oil well, so that the first bioactivator reaches the bottom of the well under the action of gravity and water flow, and finally follows the produced water to the sewage tank;

[0020] (4) Process monitoring operation: During the dosing process, the pump truck pressure, wellhead casing pressure, dosing flow rate and other parameters are monitored every 15-30 minutes through the pressure sensors, flow monitors and other equipment installed on the pump truck and wellhead casing to ensure that the bioactivator reaches the bottom of the well smoothly and is fully mixed with the produced water. If any abnormal parameters are found, the dosing parameters should be adjusted or the equipment should be checked in time.

[0021] Preferably, in step S2, the process of adding chemicals at the oil well water reinjection end further comprises the following steps:

[0022] (1) Equipment installation and operation in the station: Install the metering pump at a suitable location in the gathering and transportation station, connect the pipeline between the back-mixing water gathering and transportation pipeline and the metering pump, and perform pipeline sealing test and pressure test to ensure that the pipeline is unobstructed and leak-free;

[0023] (2) Bioactivator preparation operation: prepare a bioactivator solution according to the composition and dosage requirements of the second bioactivator in claim 1, and connect its storage tank to a metering pump;

[0024] (3) Metering pump parameter setting operation: according to the back-mixing water flow rate and the required bioactivator concentration, set the metering pump flow rate to 1-5 liters per hour and the dosing time interval to 30-90 minutes, so that the second bioactivator can be evenly added to the back-mixing water gathering pipeline;

[0025] (4) Reaction operation in the three-phase separator: The second bioactivator enters the three-phase separator along with the back-mixing water, stays in the separator for 10-60 minutes, further mixes and reacts with the produced water, and then enters the bottom of the oil well along with the back-mixing water;

[0026] (5) Bottom hole and subsequent reaction operations: During the bottom hole and subsequent production fluid transportation process, the second bioactivator continues to play a role, promoting the reproduction of native anaerobic microorganisms and inhibiting SRB. During the production fluid transportation to the surface gathering and transportation system, the sulfide content in the produced fluid is monitored every 20-40 minutes to ensure the stability of the desulfurization effect.

[0027] Preferably, in step S3, the biological sulfur control reactor process comprises the following detailed steps:

[0028] (1) Reactor installation and connection operation: transport the skid-mounted biosulfur control reactor to a suitable location at the wellhead of a single well, connect the pipeline between the wellhead and the reactor through flange connection or other sealing connection methods, and conduct an overall sealing test to ensure good sealing;

[0029] (2) Reactor filling and microbial inoculation operation: Fill the bio-ceramic biofilm material into the biological sulfur control reactor, the filling amount is 50%-80% of the reactor volume, and inoculate native anaerobic microorganisms, the inoculation amount is 1-5 kg ​​of microbial agent per cubic meter of reactor volume;

[0030] (3) Bioactivator addition and system startup operation: prepare a bioactivator solution according to the composition and dosage requirements of the bioactivator in claim 1 and add it to the biological sulfur control reactor, start the stirring device of the reactor at a stirring speed of 50-150 rpm, and start the circulation system at a circulation flow rate of 1-3 times the reactor volume per hour, so that the bioactivator is fully in contact with the microorganisms to promote the reproduction of the microorganisms;

[0031] (4) Desulfurization treatment operation: Produced water enters the biological sulfur control reactor from the wellhead at a flow rate of 0.5-2 cubic meters per hour, stays in the reactor for 30-90 minutes, and is desulfurized under the action of biological activators and a large number of native anaerobic microorganisms. The treated produced water flows out from the reactor outlet. The sulfide content of the treated produced water is monitored every 10-20 minutes by online monitoring equipment. The operating parameters of the reactor, such as the amount of biological activator added, stirring speed, circulation flow rate, etc., are adjusted according to the monitoring results to achieve the best desulfurization effect.

[0032] (III) Beneficial effects

[0033] Compared with the prior art, the present invention provides a two-phase biological desulfurization process for produced water from oil and gas fields, which has the following beneficial effects:

[0034] 1. The two-phase biological desulfurization treatment process of produced water, gas and liquid in the oil and gas field has the purpose of significant cost-effectiveness. The use of this process does not require complex equipment and expensive chemical agents, reducing investment costs. For example, compared with some oxidation methods that require high temperature and high pressure equipment or chemical methods that require a large amount of chemical agents, this process mainly relies on the action of microorganisms, and the cost of equipment and agents is greatly reduced.

[0035] The operation and maintenance costs are reduced, the microbial treatment process is relatively simple, and does not require frequent equipment maintenance and complicated operating procedures.

[0036] Reduced corrosion costs, because the sulfide content is effectively reduced, the corrosion of sulfide to oil production equipment and pipelines is reduced, the service life of equipment is extended, and costs are indirectly saved.

[0037] 2. The two-phase biological desulfurization treatment process of water, gas and liquid produced in the oil and gas field is environmentally friendly. This process is a biological treatment method. Compared with chemical methods, it is not easy to produce secondary pollution, has less impact on the environment, and meets environmental protection requirements.

[0038] 3. The oil and gas field produced water gas-liquid two-phase biological desulfurization treatment process aims to improve the benefits of oil field development, significantly improves the quality of oil field produced water and associated gas, makes wastewater easier to reinject and utilize, reduces water resource waste, and at the same time improves the safety and stability of oil and gas production, thereby increasing the overall benefits of oil field development.

[0039] 4. The two-phase biological desulfurization treatment process of produced water, gas and liquid in the oil and gas field has a wide range of applications. This process has broad application prospects. The implementation method can be flexibly selected according to the actual conditions of different oil and gas fields, such as well station conditions, pipeline transportation conditions, etc., to adapt to various working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 The process flow chart of the gas-liquid two-phase biological desulfurization treatment process of produced water from an oil and gas field in Example 1 of the present invention;

[0041] FIG2 is a process flow chart of a gas-liquid two-phase biological desulfurization process for produced water from an oil and gas field in Example 2 of the present invention;

[0042] 3 is a process flow chart of the gas-liquid two-phase biological desulfurization treatment process of produced water from an oil and gas field in Example 3 of the present invention.

[0043] In the figure: 1-1, the first bioactivator; 1-2, the first plunger pump; 1-3, the wellhead casing of the oil well; 2-1, the second bioactivator; 2-2, the metering pump; 2-3, the three-phase separator; 2-4 - oil well; 3-1, the single well; 3-2, the biological desulfurization reactor. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] See also Figure 1 -3. A two-phase biological desulfurization process for produced water, gas and liquid in oil and gas fields, comprising the following steps:

[0046] S1. Addition of bioactivator

[0047] Adding a first bioactivator (1-1) to produced water from an oil and gas field, wherein the first bioactivator (1-1) is composed of glucose and nitrate, wherein the mass ratio of glucose to nitrate is (1-5):1, and the amount of the first bioactivator (1-1) added is 10-250 grams per cubic meter of produced water;

[0048] S2. Microbial competitive inhibition

[0049] The addition of the second biological activator (2-1) promotes the massive reproduction of native anaerobic microorganisms in the produced water of the oil field. The native anaerobic microorganisms are mainly denitrifying bacteria DNB. The native anaerobic microorganisms compete with sulfate-reducing bacteria (SRB) for living space and nutrient substrates, so that the growth and reproduction of SRB are inhibited, and the inhibition rate reaches more than 85%;

[0050] S3, enzyme-catalyzed conversion

[0051] Under the action of biological enzymes, the charge and electron exchange between oxygen-containing groups in sewage and S²⁻ is promoted, so that S²⁻ is converted into SO 4 ²⁻, thereby reducing S²⁻ in the produced fluid and H in the associated gas 2 S, after treatment, the S²⁻ content in the produced fluid is reduced to 0-5 mg / L, and the H 2 The S content is reduced by more than 85% or below 20 mg / m3.

[0052] Embodiment 1:

[0053] Intermittent dosing process of oil well casing. Use a mobile dosing pump truck equipped with a plunger pump to intermittently add bioactivator to the well casing. The added bioactivator reaches the bottom of the well under the action of gravity and water flow, and finally flows to the sewage tank with the produced water. The specific operation steps are as follows:

[0054] Prepare the bioactivator by mixing glucose and nitrate in a certain concentration ratio to prepare a bioactivator solution.

[0055] Connect the mobile pump truck and the plunger pump to ensure the normal operation of the equipment.

[0056] The bioactivator solution is loaded into the tank of the mobile pump truck, and the plunger pump is started to inject the bioactivator solution into the wellhead casing of the oil well according to the predetermined interval time and dosage. For example, the dosing cycle can be set to be once every 2-5 days, and the dosage of each dosing can be determined to be 25-100 liters according to the amount of produced fluid and sulfur content of the oil well.

[0057] During the dosing process, closely observe parameters such as the pump truck pressure and wellhead casing pressure to ensure that the bioactivator reaches the bottom of the well smoothly and is fully mixed with the produced water.

[0058] The produced water carries the biological activator and the biologically treated substances into the sewage tank, where they are further precipitated, separated and processed. Figure 1 .

[0059] Embodiment 2:

[0060] Dosing process at the oil well backwash water end. The oil well backwash water is collected in the three-phase separator in the gathering and transportation station. A metering pump is installed in the station to add biological activators to the backwash water gathering and transportation pipeline. The biological activators flow into the bottom of each single well through the backwash water pipeline. The specific process is as follows:

[0061] Install metering pumps at appropriate locations in the gathering and transportation station and connect relevant pipelines to ensure that the pipelines are unobstructed and leak-free.

[0062] The bioactivator solution was prepared by mixing glucose and nitrate in a certain proportion similar to Example 1.

[0063] Connect the bioactivator solution tank to the metering pump, and set the metering pump flow and dosing time interval according to the back-mixing water flow and the required bioactivator concentration. For example, when the back-mixing water flow is 10 cubic meters per hour, the metering pump can be set to add 2 liters of dosing per hour so that the bioactivator is evenly added to the back-mixing water collection pipeline.

[0064] The bioactivator enters the three-phase separator along with the back-mixing water, further mixes and reacts with the produced water in the separator, and then enters the bottom of the single well along with the back-mixing water.

[0065] During the bottom of the well and the subsequent production fluid transportation process, the bioactivator continues to play a role, promoting the reproduction of native anaerobic microorganisms and inhibiting SRB, achieving desulfurization. See Figure 2 of the specification for the process flow

[0066] Embodiment three:

[0067] Biological sulfur control reactor process. When the well station does not have pipeline transportation, and there is no back-mixing water and well site transportation, and the biological activator cannot reach the bottom of the well to meet sufficient biological reaction time, a skid-mounted biological sulfur control reactor is connected to the wellhead for biological sulfur control and desulfurization. The biological sulfur control reactor is equipped with biofilm ceramic fillers, and the added native anaerobic microorganisms multiply in large numbers in the biological sulfur control reactor, thereby carrying out biological sulfur control and desulfurization. The specific implementation steps are as follows:

[0068] Transport the skid-mounted biosulfur control reactor to a suitable location at the wellhead, connect the pipes between the wellhead and the reactor, and ensure a good seal.

[0069] The bio-ceramic biofilm material is filled into the bio-sulfur control reactor and inoculated with native anaerobic microorganisms.

[0070] Prepare a bioactivator solution, add it into the biological sulfur control reactor, start the stirring and circulation system of the reactor, make the bioactivator fully contact with the microorganisms, and promote the reproduction of the microorganisms.

[0071] The produced water enters the biological sulfur control reactor from the wellhead of the oil well. In the reactor, it is desulfurized by the action of biological activators and a large number of native anaerobic microorganisms. The treated produced water flows out from the reactor outlet and can be operated accordingly according to the subsequent treatment requirements, such as being transported to a sewage tank or other treatment links. See Figure 3 of the specification for the process flow.

[0072] See Table 1 for detailed data: Changes in sulfide content in different single wells before and after the embodiment of the present invention

[0073] hashtag 1 2 3 4 5 6 7 8 9 10 11 12 Before dosing 10 36 12 10 5 15 4 13 40 3 3 14 After dosing 1 5 1 0 0 0 0 0 6 0 0 2 Inhibition rate (%) 90.0 86.1 91.7 100.0 100.0 100.0 100.0 100.0 85.0 100.0 100.0 85.7

[0074] It can be seen from the above table that the method of the present invention is used to treat the water-gas-liquid two-phase biological sulfur produced in oil and gas fields, which has the advantages of safety, high efficiency, environmental protection and stable operation.

[0075] The oil and gas field produced water gas liquid two-phase biological desulfurization treatment process has the purpose of significant cost-effectiveness. The use of this process does not require complex equipment and expensive chemical agents, reducing investment costs. For example, compared with some oxidation methods that require high temperature and high pressure equipment or chemical methods that require a large amount of chemical agents, this process mainly relies on microbial action, and the cost of equipment and agents is greatly reduced.

[0076] The operation and maintenance costs are reduced, the microbial treatment process is relatively simple, and does not require frequent equipment maintenance and complicated operating procedures.

[0077] Reduced corrosion costs, because the sulfide content is effectively reduced, the corrosion of sulfide to oil production equipment and pipelines is reduced, the service life of equipment is extended, and costs are indirectly saved.

[0078] With the purpose of being environmentally friendly, this process is a biological treatment method. Compared with chemical methods, it is less likely to produce secondary pollution, has less impact on the environment, and meets environmental protection requirements.

[0079] It aims to increase the revenue of oilfield development, significantly improves the quality of produced water and associated gas in the oilfield, makes wastewater easier to reinject and utilize, reduces the waste of water resources, and at the same time improves the safety and stability of oil and gas production, thereby increasing the overall revenue of oilfield development.

[0080] This process has a wide range of applications and has broad application prospects. It can flexibly select implementation methods according to the actual conditions of different oil and gas fields, such as well station conditions, pipeline transportation conditions, etc., to adapt to various working conditions.

[0081] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A two-phase biological desulfurization process for produced water from oil and gas fields, characterized in that: The following steps are involved: S1. Addition of bioactivator Adding a first bioactivator (1-1) to produced water from an oil and gas field, wherein the first bioactivator (1-1) is composed of glucose and nitrate, wherein the mass ratio of glucose to nitrate is (1-5):1, and the amount of the first bioactivator (1-1) added is 10-250 grams per cubic meter of produced water; S2. Microbial competitive inhibition The addition of the second biological activator (2-1) promotes the massive reproduction of native anaerobic microorganisms in the produced water of the oil field. The native anaerobic microorganisms are mainly denitrifying bacteria DNB. The native anaerobic microorganisms compete with sulfate-reducing bacteria (SRB) for living space and nutrient substrates, so that the growth and reproduction of SRB are inhibited, and the inhibition rate reaches more than 85%; S3, enzyme-catalyzed conversion Under the action of biological enzymes, the charge and electron exchange between oxygen-containing groups in sewage and S²⁻ is promoted, so that S²⁻ is converted into SO4²⁻, thereby reducing S²⁻ in the produced fluid and H2S in the associated gas. After treatment, the S²⁻ content in the produced fluid is reduced to 0-5mg / L, and the H2S content in the associated gas is reduced by more than 85% or below 20mg / m3.

2. The process for treating produced water from oil and gas fields by two-phase biodesulfurization of gas and liquid according to claim 1, characterized in that: In the step S1, the intermittent dosing process of the oil wellhead casing (1-3) further includes the following operations: (1) Equipment preparation operation: prepare a mobile dosing pump truck and equip it with a second plunger pump (1-2), connect the mobile pump truck and the first plunger pump (1-2), and check the sealing and pressure system of the equipment to ensure the normal operation of the equipment; (2) Bioactivator loading operation: according to the composition and dosage requirements of the first bioactivator (1-1) in claim 1, the bioactivator (1-1) is prepared into a solution and loaded into the storage tank of the mobile pump truck; (3) Dosing parameter setting operation: set the dosing dosage of the first plunger pump (1-3) to a dosing cycle of once every 2-5 days, determine the dosing dosage of each time to be 25-100 liters according to the produced fluid volume and sulfur content of the oil well, start the first plunger pump (1-3) to inject the first bioactivator (1-1) solution into the wellhead casing (1-3) of the oil well, so that the first bioactivator (1-1) reaches the bottom of the well under the action of gravity and water flow, and finally follows the produced water to the sewage tank; (4) Process monitoring operation: During the dosing process, the pump truck pressure, wellhead casing pressure, dosing flow rate and other parameters are monitored every 15-30 minutes through the pressure sensors, flow monitors and other equipment installed on the pump truck and wellhead casing to ensure that the bioactivator reaches the bottom of the well smoothly and is fully mixed with the produced water. If any abnormal parameters are found, the dosing parameters should be adjusted or the equipment should be checked in time.

3. The process for treating produced water from oil and gas fields by two-phase biodesulfurization of gas and liquid according to claim 1, characterized in that: In step S2, the process of adding chemicals at the oil well water reinjection end further includes the following steps: (1) Equipment installation and operation in the station: Install the metering pump (2-2) at a suitable location in the gathering and transportation station, connect the pipeline between the back-mixing water gathering and transportation pipeline and the metering pump (2-2), and perform pipeline sealing test and pressure test to ensure that the pipeline is unobstructed and leak-free; (2) Bioactivator preparation operation: prepare a bioactivator solution according to the composition and dosage requirements of the second bioactivator (2-1) in claim 1, and connect its storage tank to the metering pump (2-2); (3) Metering pump parameter setting operation: according to the back-mixing water flow rate and the required bioactivator concentration, set the flow rate of the metering pump (2-2) to 1-5 liters per hour and the dosing time interval to 30-90 minutes, so that the second bioactivator (2-1) can be evenly added to the back-mixing water collection pipeline; (4) Reaction operation in the three-phase separator: The second bioactivator (2-1) enters the three-phase separator (2-3) along with the back-mixing water, stays in the separator for 10-60 minutes, further mixes and reacts with the produced water, and then enters the bottom of the oil well (2-4) along with the back-mixing water; (5) Bottom hole and subsequent reaction operations: During the bottom hole and subsequent production fluid transportation process, the second bioactivator continues to play a role, promoting the reproduction of native anaerobic microorganisms and inhibiting SRB. During the production fluid transportation to the surface gathering and transportation system, the sulfide content in the produced fluid is monitored every 20-40 minutes to ensure the stability of the desulfurization effect.

4. The process for treating produced water from oil and gas fields by two-phase biodesulfurization of gas and liquid according to claim 1, characterized in that: In step S3, the biological sulfur control reactor process includes the following detailed steps: (1) Reactor installation and connection operation: transport the skid-mounted biosulfur control reactor (3-2) to a suitable location at the wellhead of a single well (3-1), connect the pipeline between the wellhead and the reactor through flange connection or other sealing connection methods, and conduct an overall sealing test to ensure that the sealing is good; (2) Reactor filling and microbial inoculation operation: Fill the biological sulfur control reactor (3-2) with bioceramic biofilm material, the filling amount is 50%-80% of the reactor volume, and inoculate native anaerobic microorganisms, the inoculation amount is 1-5 kg ​​of microbial agent per cubic meter of reactor volume; (3) Bioactivator addition and system startup operation: prepare a bioactivator solution according to the composition and dosage requirements of the bioactivator in claim 1 and add it to the biological sulfur control reactor (3-2), start the stirring device of the reactor at a stirring speed of 50-150 rpm, and start the circulation system at a circulation flow rate of 1-3 times the reactor volume per hour, so that the bioactivator is fully in contact with the microorganisms to promote the reproduction of the microorganisms; (4) Desulfurization treatment operation: produced water enters the biological sulfur control reactor (3-2) from the wellhead of the oil well at a flow rate of 0.5-2 cubic meters per hour, stays in the reactor for 30-90 minutes, and is desulfurized under the action of biological activators and a large number of native anaerobic microorganisms. The treated produced water flows out from the reactor outlet. The sulfide content of the treated produced water is monitored every 10-20 minutes by online monitoring equipment. The operating parameters of the reactor, such as the amount of biological activator added, stirring speed, circulation flow rate, etc., are adjusted according to the monitoring results to achieve the best desulfurization effect.

Images