Reasons of low yield and stimulation measures for CBM wells in Junlian area

Coalbed methane fields in Junlian area have good development potential, but the existence of a large number of low-production and low-efficiency wells has restricted the increase of productivity. This paper analyzes the coupling relationship between high-productivity wells and geological factors from the perspective of geological engineering integration, analyzes the causes of inefficient wells from three aspects of geology, drainage and engineering, and evaluates the corresponding reform measures. The results show that the formation of inefficient wells in the north and the west of the study area is mainly affected by gas-bearing properties, fault distribution, production horizons, production and drainage rhythms, and fracturing channeling wells. High-production wells in the middle and the south area have low water production, low flow pressure, long drainage time, low pulverized coal production and high TDS. For the treatment of low yield wells, it is found that the pickling effect is better, the secondary hydraulic fracturing needs to strictly control the construction parameters, and the effect of shock plugging is not obvious. The treatment of low-yield and low-efficiency wells for coalbed methane should start from the deployment of well locations, and carry out well location design and construction management around the integration of geology-engineering-discharge production.