CN-121988161-A - Method and device for removing sulfur-containing gas in oil well by biological method

CN121988161ACN 121988161 ACN121988161 ACN 121988161ACN-121988161-A

Abstract

The invention relates to the field of oil and gas field development and discloses a method for removing sulfur-containing gas in an oil well by a biological method, which comprises the steps of injecting a medicament A with the concentration of y 1 mg/L into the oil well according to a correlation formula y 1 ＝20a×Lgx 1 , injecting a medicament A with the concentration of y 1 mg/L into the oil well according to a correlation formula y 1 =20a×Lg2, injecting a medicament B with the concentration of y 2 mg/L into the oil well according to a correlation formula y 2 ＝30b/Lgx 2 , injecting a medicament B with the concentration of y 2 mg/L into the oil well according to a correlation formula y 2 >2, and injecting a medicament B with the concentration of x 2 less than or equal to 2 according to a correlation formula y 2 =30b/Lg 2, wherein the concentration of sulfate reducing bacteria in the oil well is x 1 CFU/mL, the concentration of beneficial bacteria in the oil well is x 2 CFU/mL, a and B are actual value coefficients, a is less than or equal to 2, and 1 is less than or equal to 10, the medicament A comprises sulfur removing bacteria, and the medicament B comprises nutrients. The reagent concentration is determined by utilizing the correlation, so that the reagent adding stability is realized, the sulfur removal effect can be effectively improved, the reagent adding is more scientific, and the sulfur removal cost is reduced.

Inventors

QIAN ZHIHONG
YANG FAN
HOU KEQI
JIANG GUIYING
WANG ZHIMING
GONG JIAYU

Assignees

中国石油化工股份有限公司
中国石油化工股份有限公司江苏油田分公司

Dates

Publication Date: 20260508
Application Date: 20241108

Claims (10)

1. A method for biologically removing sulfur-containing gas from an oil well, the method comprising: Injecting a medicament A with the concentration of y 1 mg/L into an oil well according to a correlation formula y 1 ＝20a×Lgx 1 , wherein x 1 is more than 2; Injecting a medicament A with the concentration of y 1 mg/L into an oil well according to the correlation y 1 = 20a x Lg2, wherein x 1 is less than or equal to 2; Injecting a medicament B with the concentration of y 2 mg/L into the oil well according to the correlation y 2 ＝30b/Lgx 2 , wherein x 2 is more than 2; Injecting a medicament B with the concentration of y 2 mg/L into the oil well according to the correlation y 2 = 30B/Lg2, wherein x 2 is less than or equal to 2; the concentration of sulfate reducing bacteria in the oil well is x 1 CFU/mL, the concentration of beneficial bacteria in the oil well is x 2 CFU/mL, a and b are value coefficients, a is less than or equal to 2, and b is less than or equal to 1 and less than or equal to 10; the agent A comprises a sulfur removal bacterial agent; The agent B includes a nutritional agent.
2. The method of claim 1, wherein, When x 1 is greater than or equal to 1000 and x 2 is less than 100, 1.5 is greater than or equal to a is less than or equal to 2, and/or When x 1 is greater than or equal to 1000 and x 2 is greater than or equal to 100, 1 is greater than or equal to a <1.3, and/or When x 1 <1000, and x 2 <100, 1.2≤a <1.5, and/or When x 1 is less than 1000 and x 2 is greater than or equal to 100, 0 is less than or equal to a <1, and/or When x 1 is less than 1000 and x 2 is greater than or equal to 1000, 1 is less than or equal to b is less than or equal to 2.5, and/or When x 1 is less than 1000 and x 2 is less than 1000, 2≤b is less than 4, and/or When x 1 is greater than or equal to 1000 and x 2 is less than 1000, 5 is less than or equal to b is less than or equal to 10, and/or When x 1 is greater than or equal to 1000 and x 2 is greater than or equal to 1000, 1.5 is greater than or equal to b <5.
3. The method according to claim 1 or 2, wherein, The sulfate reducing bacteria are selected from one or more of the genus Vibrio and the genus Enterobacter desulphus; And/or The beneficial bacteria are selected from one or more of denitrifying bacteria strains, and/or The oil well is Jiangsu oil field oil well, and/or Agent a addition z 1 = oil well fluid volume x water cut x y 1 , and/or The addition amount z 2 of the agent B is =the oil well liquid amount×the water content×y 2 , and/or The interval calculation period of the concentration of the medicament A and the concentration of the medicament B is 2-8 days.
4. A method according to any one of claims 1 to 3, wherein the concentration of sulfate-reducing bacteria in the well is measured by taking a sample of the produced fluid from the well, subjecting the sample of the produced fluid to oil-water separation to obtain oil and water, and measuring the water to obtain a concentration of sulfate-reducing bacteria in the sample of the produced fluid which is the concentration of sulfate-reducing bacteria in the well.
5. The method according to any one of claims 1-4, wherein the concentration of beneficial bacteria in the well is measured by extracting a sample of produced fluid from the well, subjecting the sample of produced fluid to oil-water separation to obtain oil and water, and measuring the water to obtain the concentration of beneficial bacteria in the sample of produced fluid as the concentration of beneficial bacteria in the well.
6. The method according to claim 4 or 5, wherein the method further comprises: after determining the agent concentration y 1 , adding agent A to the water according to the agent concentration y 1 , returning the agent treated water to the well, and/or After determining the reagent concentration y 2 , adding the reagent B into the water according to the reagent concentration y 2 , and returning the water treated by the reagent to the oil well; Preferably, the return speed is 0.5-2m 3 /d.
7. A device for removing sulfur-containing gas in an oil well by a biological method according to any one of claims 1 to 6, which is characterized by comprising an oil-water separation unit, a biological bacteria monitoring unit and a linkage fluid replacement unit which are communicated in sequence; the oil-water separation unit is used for separating oil from water of the oil well produced liquid sample; the biological bacteria monitoring unit is used for detecting the concentration x 1 of sulfate reducing bacteria and the concentration x 2 of beneficial bacteria in the water material after oil-water separation; The linkage fluid infusion unit infuses the medicament B with the concentration of the medicament A, y 2 with the concentration of y 1 into the water material after oil-water separation and then infuses the water material into an oil well through the concentration y 1 of the medicament A and the concentration y 2 of the medicament B by a linkage decision.
8. The apparatus of claim 7, wherein, The oil-water separation unit comprises a tank body, an inlet and an outlet; Preferably, the lower end of the inlet is at least provided with two corrugated plates, a channel for the produced liquid to flow through is arranged between two adjacent corrugated plates, and the corrugated plates are obliquely arranged relative to the length direction of the tank body; more preferably, the angle of inclination is 15 ° -75 °.
9. The device according to claim 7 or 8, wherein, The biological bacteria monitoring unit comprises a circulating pipeline and a sampling port arranged on the pipeline, wherein the sampling port is used for sampling on site and detecting the concentration x 1 of sulfate reducing bacteria and the concentration x 2 of beneficial bacteria; Preferably, the circulating pipeline is provided with a filter screen for filtering water materials after oil-water separation.
10. The device according to any one of claims 7-9, wherein, The linkage fluid infusion unit comprises a calculation unit and a dosing unit; Preferably, the calculation unit injects a medicament A with the concentration of y 1 mg/L into the oil well according to a correlation formula y 1 ＝20a×Lgx 1 , x 1 is larger than 2, injects a medicament A with the concentration of y 1 mg/L into the oil well according to a correlation formula y 1 =20a×Lg2, x 1 is smaller than or equal to 2, injects a medicament B with the concentration of y 2 mg/L into the oil well according to a correlation formula y 2 ＝30b/Lgx 2 , x 2 is larger than 2, injects a medicament B with the concentration of y 2 mg/L into the oil well according to a correlation formula y 2 =30b/Lg 2, x 2 is smaller than or equal to 2, and determines the medicament A addition and the medicament B addition according to a correlation formula medicament A addition z 1 =oil well liquid amount×water content×y 1 , and a medicament B addition z 2 =oil well×water content×y 2 ; Preferably, the dosing unit injects the medicament B with the concentration of the medicament A, y 2 with the concentration of y 1 determined by the calculating unit into the water material after oil-water separation through the dosing pump, and then injects the medicament B into the oil well according to the addition amount of the medicament A and the medicament B determined by the calculating unit.

Description

Method and device for removing sulfur-containing gas in oil well by biological method Technical Field The invention relates to the field of oil and gas field development, in particular to a method and a device for removing sulfur-containing gas in an oil well by a biological method. Background In the oil field exploitation process, a great amount of hydrogen sulfide exists in associated gas generated by partial oil wells, so that the problems of safety and environmental protection are caused. At present, chemical or biological sulfur removal is commonly used for treating the oil well, wherein the chemical sulfur removal method mainly reduces the concentration of hydrogen sulfide in associated gas of the oil well through chemical reaction of a desulfurizing agent and the hydrogen sulfide, and the biological sulfur removal technology principle mainly inhibits the basic sulfate reducing bacteria for producing the hydrogen sulfide in the produced liquid of the oil well through introducing or activating dominant bacteria and biological competition among microorganisms, so that the concentration of the hydrogen sulfide in the associated gas of the oil well is greatly reduced. In order to control the hydrogen sulfide at the wellhead of the oil well more stably, a conventional method is adopted to connect a dosing pump at the wellhead of the oil well to continuously add a sulfur removing agent or a microbial inoculum, so as to realize the purpose of stably controlling the hydrogen sulfide. Biological desulfurization has the advantages of green, environmental protection and the like, and is a main trend of sulfur removal of oil wells in future oil fields. From the current application situation, the advantages of long-acting and economical performance of microorganisms cannot be fully exerted in the implementation process. The method has the main advantages that the mode of continuously adding the nutritional agent to the wellhead after intensively adding the microbial inoculum is adopted, so that the defects of continuously reducing the microbial concentration at the bottom of the oil well caused by the fact that bacteria easily enter the oil transportation flow along with produced liquid exist, limiting the continuous nutritional agent adding to the wellhead by the size of a ground medicine storage tank, limiting the daily medicine adding volume, and influencing the growth of the microbial inoculum due to the fact that the actual medicine adding amount is less than the set amount due to losses of sticking the wellhead to the bottom of the well and the like are overcome. Disclosure of Invention Aiming at the problem of medicament waste caused by inaccurate medicament adding and effect judgment in the conventional biological sulfur removal process, the invention utilizes the correlation type to determine the medicament concentration, can effectively improve the sulfur removal effect, is more scientific in medicament adding, reduces the sulfur removal cost, and can realize medicament adding stability, and the device can detect the quantity of sulfate reducing bacteria and beneficial bacteria in real time to carry out periodic and dynamic medicament adding. In order to achieve the above object, the present invention provides, in one aspect, a method for biologically removing sulfur-containing gas in an oil well, the method comprising: Injecting a medicament A with the concentration of y 1 mg/L into an oil well according to a correlation formula y 1＝20a×Lgx1, wherein x 1 is more than 2; Injecting a medicament A with the concentration of y 1 mg/L into an oil well according to the correlation y 1 = 20a x Lg2, wherein x 1 is less than or equal to 2; Injecting a medicament B with the concentration of y 2 mg/L into the oil well according to the correlation y 2＝30b/Lgx2, wherein x 2 is more than 2; Injecting a medicament B with the concentration of y 2 mg/L into the oil well according to the correlation y 2 = 30B/Lg2, wherein x 2 is less than or equal to 2; The concentration of sulfate reducing bacteria in the oil well is x 1 CFU/mL, the concentration of beneficial bacteria in the oil well is x 2 CFU/mL, a and b are actual value coefficients, a is less than or equal to 2, and b is less than or equal to 1 and less than or equal to 10; the agent A comprises a sulfur removal bacterial agent; The agent B includes a nutritional agent. The second aspect of the invention provides a device for removing sulfur-containing gas in an oil well by a biological method, which comprises an oil-water separation unit, a biological bacteria monitoring unit and a linkage fluid replacement unit which are sequentially communicated; the oil-water separation unit is used for separating oil from water of the oil well produced liquid sample; the biological bacteria monitoring unit is used for detecting the concentration x 1 of sulfate reducing bacteria and the concentration x 2 of beneficial bacteria in the water material after oil-water separation; Th