特低渗油藏微生物矿场试验效果评价  

Evaluation of MEOR Field Trial Results in Reservoirs with Very Low Permeability

作　　者：石梅[1] 侯兆伟[1] 李蔚[1] 王颖[1] 陈星宏[1] 韩培慧[1] 杨振宇[1] 陈宗运[1] 

机构地区：[1]中国石油大庆油田公司勘探开发研究院,黑龙江大庆163712

出　　处：《油田化学》2003年第3期269-272,共4页Oilfield Chemistry

基　　金："九五"中国石油天然气集团公司攻关项目 ( 9612 10 60 9)

摘　　要：大庆外围朝阳沟油田 2 0 0 2年 8～ 9月在 13口油井进行了微生物吞吐采油现场试验。所用菌种为兼性厌氧混合菌。 13口井的油层按渗透率分为 3类 ,Ⅰ类 6口 ,18.2× 10 -3 μm2 ,Ⅱ类 4口 ,8.2× 10 -3 μm2 ,Ⅲ类 3口 ,4 .5×10 -3 μm2 。单井菌液注入量为 0 .9～ 3.0t,注菌后关井 5～ 7d(一口井关井 2 0d)。原油与菌种作用后正构烷烃分布移向低碳数方向 ,粘度 剪切速率曲线大幅度下移。跟踪检测的 3口试验井 ,注菌后产出的原油含蜡、含胶、油水界面张力分别由 2 7%～ 4 0 %、18%～ 2 2 %、32～ 36mN/m降至 17%～ 15 %、11%～ 16 %、14～ 17mN/m ,产出水中有机酸含量由 5 0～ 6 5mg/L增至 10 9～ 138mg/L ,其中一口井注菌 2 0和 15 0d天后采出水中菌数为 10 7和 10 5个 /mL ,室内实验表明在注入营养物后地层的微生物可继续生长繁殖。现场试验结果表明 ,5口Ⅰ类地层井微生物吞吐采油效果 (增油减水 )良好 ,3口Ⅱ类地层井和 2口Ⅲ类地层井效果差但仍有效。对 3口井无效的原因作了分析。图 2表 5参A microbes huff puff trial has been performed on 13 production wells of peripheral Chaoyanggou oil field in Daqing to stimulate the reservoirs in Aug-Sept, 2002. The microbes used are mixed facultatively anaerobic. The 13 wells are divided into 3 classes according to reservoir permeability: 6 wells of class Ⅰ, 18.2×10 -3 μm 2; 4 wells of class Ⅱ, 8.2×10 -3 μm 2; and 3 wells of class Ⅲ, 4.5×10 -3 μm 2. The amount of bacterial culture injected is of 0.9-3.0 t/well and the well closed in 5-7 d (20 d in one of the wells) before starting production. The distribution of normal alkanes in the crude is shifted towards lower carbon number and its viscosity shear rate curve - downwards. The response of the 3 wells under specially monitoring to microbes injection can be described by following data: significant decrease in wax and resin asphaltene contents of the crude produced and in interfacial tension between produced water and crude from 27-40%, 18-22%, and 32-36 mN/m to 17-25%, 11-16%, and 14-17 mN/m, respectively; increase in content of organic acids in produced water from 50-65 mg/L to 109-138 mg/L. The bacterial population in produced water of one well is of 10 7 and 10 5 cell/mL in 2 and 150 d after microbes injection and injection of nutrients can reactivate the microbes injected into the reservoir, as evidenced in the laboratory experiments. The field trial results show that the respone to microbes huff puff in enhancing oil recovery and in lowering water cut of 5 wells of class Ⅰ is very good, of 3 wells of class Ⅱ and of 2 wells of class Ⅲ - poor. The negative response of other 3 wells is reasoned.

关 键 词：特低渗油藏 微生物采油 矿场试验 兼性厌氧菌 微生物吞吐 效果分析 大庆朝阳沟油田 

分 类 号：TE357.9[石油与天然气工程—油气田开发工程] TE348