The production of coalbed methane wells is carried out by pumping the confined water in the coal reservoir, so that the coal seam pressure is reduced below the desorption pressure of the coal, and the methane desorption in the adsorbed state is a large amount of free methane, and is transported to the wellbore by diffusion and seepage.

In 2015, a coalbed methane stratified drainage combined gas production process string was required in the Suinan CBM exploration project under the responsibility of Xi'an Research Institute of China Coal Science and Technology Group. The schematic diagram of the CBM drainage pipe column in Suinan is shown in the right figure. This project belongs to the experimental development well. A special packer is added in the middle of the coal seam. The packer needs four channels. The main channel of the packer is the working channel of the tubular pump; a gas passage for the gas in the lower part of the packer to escape to the upper part of the packer; a liquid passage for the water in the upper part of the packer to flow into the lower part of the packer; Cable channel. In addition to the packer, the column configuration includes tools such as a telescopic compensator, an IPO circulation valve, a centralizer, and a safety joint. The bottom of the column is a tube pump, which extracts the water that penetrates the coal seam into the annulus, reduces the pressure of the coal seam, desorbs the coalbed methane in the coalbed state, and discharges the gas from the annulus. Through this process pipe column, coalbed methane stratified drainage can be realized, and the drainage efficiency is improved.
Our company is responsible for design and development. After nearly half a year of research and development and repeated trials in the factory, the CBM drainage and gas production process pipe string successfully entered the well in the XXX13V-08 well in Suinan, Anhui Province in 2016 and passed the site acceptance. The depth of the well is 1055 meters, the coal seam is located at 914 meters to 1002.25 meters, the surface casing is Φ244.5mm, the wall thickness is 8.94mm, the penetration depth is 324.80 meters, the production casing is Φ139.7mm, the wall thickness is 9.17mm, the penetration depth is 1054.70 meters, the coal seam The well section is subjected to perforating fracturing operations.
After late return visit users, their recovery rate increased by more than 50%.
This well is currently the first coalbed methane well in China.
Packer into the well

Connecting drainage gas collection pipe

Connect electric pump cable