煤层气井空气钻井条件下地质录井面临的新问题及解决方法

New Problems and Resolvents in CBM Well Geological Logging under the Condition of Air Drilling

煤层气空气钻井技术有利于保护煤层的原生结构,提高产气量,在大幅度提高钻井效率的同时,也给判别地层岩性和准确判断煤层层位等录井工作带来了新的问题。结合山西沁水煤田晋城煤层气勘探开发应用情况,介绍了空气钻井技术在岩屑捞取、气测录井中的气体采集与过滤以及SMY-2型岩屑伽马监测仪的应用情况,提供了岩屑迟到时间的理论计算与实际测量方法、地层出水的判别及出水量大小的分类方法及空气钻井气测录井的净化流程。

The CBM air drilling technology is favorable to protect coal seam primary structure, increase methane yield, raise drilling efficiency substantially, but at one time, bring along with new problems in well logging such as strata lithologic differentiation and coal seam correct position etc. Combined with Shanxi Province Qinshui coalfield and Jincheng CBM exploration and exploitation situation, introduced air drilling technological application in fishing of cuttings, gas collection and filtering in gas logging and SMY-2 cutting gamma monitor, provided cutting lagged time theoretical computation and practical measuring methods, strata outflow determination and water yield classification, as well as cleaning process of air drilling gas logging.