Coalbed methane recovery from multilateral horizontal wells in Southern Qinshui Basin

Abstract

Since 2006, more than 80 multilateral horizontal wells have been drilled in Panzhuang block, Southern Qinshui Basin. In this paper, 6 typical wells in a region are selected as an example. The thickness of coal, gas content, reservoir pressure, permeability, burial depth, and reservoir pressure conditions are analyzed. The practice shows that production by multilateral horizontal well declines from 43,111 m 3 /day per well in the 2nd year to 25,126 m 3 /day per well in the 4th year. The numerical simulation result shows that the lateral interference forms in Well QNP05 after two years of gas production, and the gas content is reduced to less than 8 m 3 /t within the controlled region after six years. The area of gas content was less than 8 m 3 /t after eight years of gas production is about 3.2 km 2 , which is about 76% of the controlled area of the six multilateral horizontal wells. The results indicate that multilateral horizontal wells contribute to high production rates at potentially profitable levels and can also serve as an effective tool for a high-rank CBM field drainage. Cited as : Liu, S., Tang, S., Yin, S. Coalbed methane recovery from multilateral horizontal wells in Southern Qinshui Basin. Advances in Geo-Energy Research, 2018, 2(1): 34-42, doi: 10.26804/ager.2018.01.03