微生物提高煤层气井单井产量技术研究与实践

Microbially enhanced CBM well production rate technology and its application

任付平 韩长胜 王玲欣 郑雅 郭素贞 刘斌

REN Fuping HAN Changsheng WANG Lingxin ZHENG Ya GUO Suzhen LIU Bin

华北油田公司采油工程研究院 华北油田公司二连分公司 渤海钻探工程有限公司第二录井分公司 华北油田公司煤层气勘探开发指挥部

Oil Production Engineering Research Institute of PetroChina Huabei Oilfield Company, Renqiu, Hebei 062552, China Erlian Oilfield Company of PetroChina Huabei Oilfield Company, Xilingol League, Inner Mongolia 026000, China No.2 Logging Company of PetroChina Bohai Drilling Engineering Company Limited, Renqiu, Hebei 062552, China CBM Exploration and Development Headquarter of PetroChina Huabei Oilfield Company, Renqiu, Hebei 062552, China

为评价微生物提高煤层气井产量技术，向厌氧瓶中添加一定量的煤和利用煤层产出液配置的营养液，开展了煤层微生物降解煤产气实验研究。与煤层产出液相比较有益菌群浓度增加3~6 个数量级，每毫升营养液产气量为2.84 mL，煤层微生物经过营养剂激活后，反应早期产生气体主要为N2、H2 和CO2，CH4 含量较低，随着反应时间延长CH4 气体含量逐渐增加，X 射线衍射表明煤微晶结构发生变化。说明通过微生物与煤相互作用产生生物气体、降解煤组分，能增加煤层通透率促进甲烷气体的解吸，从而提高煤层气单井产量。在室内研究的基础上开展现场先导试验1 井次，现场共注入微生物工作液230 m3，措施前该井平均日产气量16.81 m3，平均套压为0.09 MPa，措施后该井日产气75.13 m3，平均套压0.35 MPa，截至2015 年底累计产气14 100 m3，目前正在持续稳产，达到了注微生物提高煤层气井单井产量的目的。

In order to evaluate the microbially enhanced coalbed methane (CBM) well production rate technology, an experimental study was performed on the gas generation through microbial coalbed degradation by adding a certain amount of coal and the nutrient solution prepared with produced coalbed fluid into the anaerobic bottle. The effective microbial community density of nutrient solution was 3-6 orders of magnitude higher than that of the produced coalbed liquid. Gas production per milliliter of nutrient liquid was 2.84 mL.After the coalbed microbes were activated by the nutrient solution, N2, H2 and CO2 were the dominant products with lower CH4 content at the early stage of reaction. With the proceeding of reaction, CH4 content increased gradually. The X-ray diffraction suggests the structural changes of coal micro-crystal. It is indicated that the interaction between microbes and coal allows for the generation of biogas and the degradation of coal composition, thereby improving the coalbed permeability. And consequently, methane desorption is promoted and CBM well production is increased. After the laboratory experiment, field pilot test was conducted in one well time by injecting 230 m3 microbial fluid. Before the treatment was made, average daily gas production rate of this well was 16.81 m3 and average casing pressure was 0.09 MPa. After the treatment was made, its average daily gas production rate was 75.13 m3, average casing pressure was 0.35 MPa and cumulative gas production was 14 100 m3. At present, this well is at stable production stage. Obviously, the purpose of enhancing CBM well production rate by microbe injection is reached.

10.13639/j.odpt.2016.03.023