Stimulation Unlocks Coalbed Methane: Lessons Learned in India

摘要

Although gas production from coalbed methane (CBM) wells has become an important source of energy in North Americaover last couple of decades, it still remains an upcoming area in India. India has the fourth-largest proven coal reserves in theworld and therefore considerable prospects exist for exploration and exploitation of CBM. Development of CBM and otherunconventional gas sources are currently a priority for India to meet its growing energy demand.An effort has been made in this paper to review the lessons learned from the stimulation and production of Raniganj CBMfield in India. Experiences from large number of CBM operations in the US and Australia have been useful in this regard,however several constraints specific to India had to overcome to make the campaign successful:1.India is an extremely cost-sensitive market.2.Location sizes are limited, making the logistics very challenging.3.Land acquisition problems, resulting in different drilling and field development strategies employed.4.Seasons/weather challenges in the northeastern part of India, where most of the CBM blocks are located.5.Proppant flowback is a problem due to lower closure stress.This paper will review over 150 recent hydraulic fracture treatments in CBM wells in India. It will summarize differentdrilling and perforation strategies, completion practices, hydraulic fracturing design considerations, job execution, difficultiesfaced and solutions employed in India to overcome the difficulties. It will conclude with lessons learned that can be applied infuture wells.