Optimization and practice of horizontal well azimuth in thick and high dip-angle coalbed in Fukang mining area

In order to solve the problem of horizontal borehole azimuth in thick and high dip-angle coalbed in Fukang mining area, a comprehensive reservoir modeling and productivity prediction for nine different horizontal borehole trajectory azimuth was completed by using the COMET3. The results show that when the horizontal borehole trajectory was at updip direction, the coal seam strike, the cumulative gas production decreased slightly with increase of the included angle of seam strike and horizontal well trajectory; When the horizontal well trajectory was at downdip direction, the cumulative gas production decreased greatly with increase of the included angle. Research results revealed that the best direction of horizontal borehole should be built up along the coal seam strike or swing at small angle along the coal seam strike. The first horizontal CBM well completed in the west of Fukang mining area has confirmed the technical feasibility of these analyses, and the research results have great guidance and reference significance for optimization technology of CBM efficient development in similar reservoirs of Xinjiang.