三次采油菌种982和L-510的单井吞吐试验

Results of First Cycle Microbes Well Huffing-Puffing Trial in Pubei,Daqing

菌种982有降低原油黏度和清除蜡沉积的作用，菌种L-510可产生物表面活性剂，分离自大庆油田，属蜡状芽孢杆菌。菌液由专业厂家生产，菌数〉10^8个／n也。根据选井原则，在油层中部温度60℃的葡北过渡带选取原油黏度〉15mPa·s、含蜡量〉20％、含水33．9％～86．2％、油层有效厚度2．4～8，4m、产油量0．4～3．6t／d的10口油井，实施了一个轮次的982＋L-150微生物吞吐试验。根据油井静、动态参数，取处理半径为4～5m，菌种982和L-510比例在5：2～5：10之间，单井注入菌液3．5～6．0t，微生物段塞尺寸55～60t，以0．1～0．15m^3／min的排量经由套管注入油井，并井3天后开井生产。10口井中大部分井压力上升，泵效和沉没度增大；大部分井产液量、产油量增大，含水下降，有效期平均为153天；有8口井产出的原油黏度和含蜡量均增大，黏度最大增幅26．39mPa·s，含蜡量最大增幅为26．35个百分点。4口井的监测数据表明，开井生产后产出液中菌数大幅上升至10。个／n也以上，5个月内维持在10^4个／n1L水平；从产出液中还分离出了注入菌种。图5表4参7。

Strain 982, bacterial species capable of reducing oil viscosity and removing wax precipitates, and strain 1-510, biosurfactant producing species, are both Bacillus cereus and are isolated and sieved from Daqing oil fields. The fermentation broth used for trial contains 2〉10^8 ctu/mL. According to well selection roles, 10 oil wells of oil viscosity 2〉15 mPa＇s, wax content 2〉20%, net pay thickness 2.4-8.4 m, and oil output 0.4-3.6 t/d in transitional zones of Pubei oil field, Daqing, with medium layer temperature 60℃ are selected to conduct a trial project on MEOR by using strains 982 ＋ 1-510 well huffing-puffing technology of first cycle. On the basis of reservoir physical characteristics and well performance, the bacterial treating radius is of 4-5 m, the proportions of strains 982 and L-510 are in range 5：2-5 ： 10, the mass of mixed broth injected is in range 3.5-6.0 t and is admixtured in 55-60 t injection water as bacterial slug, which is injected at a flow rate 0.1-0.15 m^3/min through annulus into the oil wells, the laters are closed for 3 days and then restart oil production. In the most wells of 10, a raise in flowing pressure, pumping efficiency, and submergence is observed, the increase in mass of total fluids produced and in oil output and the decrease in watercut continue for 153 days in average. The viscosity and wax content of oil produced from 8 wells are inceased with the highest increment of 26.39 mPa·s and 26.35%, respectively. The monitoring data on 4 wells show that the bacterial population in the produced water from the restarted wells grows significantly to more than 106 ctu/mL at first and maintains at a level of 10a ctu/mL in 5 months; the strains injected are isolated in the produced water.