Research and application of roof refracturing technology for controlled bottom seam height of coalbed methane well in Hancheng Block
In order to solve the problem of poor effect of conventional refracturing technology in soft crushed coalbed methane old wells in Hancheng Block,Ordos Basin,a refracturing technology of roof controlled bottom combined with secondary sand addition and roof fracturing was proposed in this paper via analyzing the effect of initial fracturing and the characteristics of residual gas produc-tivity by taking well X as the research object.The experiment and numerical simulation software were used to optimize the construc-tion parameters,and the three-stage sand addition process of 100-mesh quartz sand bottom control and temporary plugging of the old joint and 40/70 mesh+20/40 mesh quartz sand supported new joint technology was selected.The optimized perforation position was 3-5 m from the top of the coal seam,the construction displacement was 9 m3/min,and the average sand addition ratio was 9%.The roof-controlled bottom refracturing technology is formed to increase reservoir reconstruction volume and improve reservoir utilization degree.Field tests were carried out in well X,and after repeated fracturing,the new gas production was 2.681 million m3.Eighteen wells were applied,and the average daily gas production per well was increased by 1 210.42 m3,which effectively solved the prob-lem of poor re-fracturing effect of soft crushed coalbed methane old wells,and could meet the demand of cost reduction and efficiency elevation in secondary development and fracturing operations of coalbed methane old wells.The technology developed herein has good value of popularization and application.
coalbed methaneHancheng Blockcrushed soft coal seamrefracturing old wellstemporary proppant plugging
万方数据
维普
