Horizontal wells are drilled within Reliance Coalbed Methane (CBM) in India to increase productivity. This can be facilitated by reducing FBHP to a minimum. The commingled flow of gas and water causes high Gas Volume Fraction (GVF) at pump intake. Gas separators with suitable lifting systems were critical to reduce GVF. Well completion was designed with Progressive Cavity Pumps to handle the production of coal fines whilst catering to the chances of high rod-tubing wear.

(GAS HANDLER PCP) were expected to provide improved run-life in these conditions. Software simulation was used to optimize the placement of rod guides and centralizers on the rod string to minimize tubing integrity problems. The process of evaluation and optimization involved the deployment of different Well completion of AL and Gas separators with a provision for metering free gas from tubing to determine GVF. Well, operation and monitoring were optimized with the use of RPM, flow rate, and GVF. Minimum pump submergence was respected to avoid pump failure. Both PCPs and GAS HANDLER PCPs were installed to provide a run-life comparison

The results of the trial have been positive to date, and The GAS HANDLER PCP along with the designed well completion has allowed run times of the pump to increase significantly. The rod string design through Software simulation supplemented the increased run times achieved. Remarkable improvement in reducing GVF was accomplished by proper selection of gas separator. The combination of a gas separator and GAS HANDLER PCP has achieved a very low Flowing Bottom Hole Pressure (FBHP – 20 to 25 psi) for an acceptable period. After successful results from the completion of the trial, Reliance CBM has scaled up the implementation of this technology in multi-lateral CBM Horizontal wells. It has proven to be the most cost-effective method to complete and produce from a CBM horizontal well. With the substantial increase in productivity from CBM wells this technology is set to change the course of how CBM field can be developed more productively.

Work is continuing to improve the well production lifespan with the addition of a Tubing Rotator and close monitoring of tubing wear analysis. It will eliminate the cumbersome and costly hydraulic fracturing (HF) operations in coal seams with or without contrasting boundaries (shale boundary). Significant reduction in environmental hazards due to HF is an advantage, that will encourage more operators to adopt this technology. Horizontal wells in CBM will enhance the gas production output of India.

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