METHOD OF ANALYSING PRODUCTIVITY OF COAL BEDS IN COAL-METHANOL WELLS SYSTEM Russian patent published in 2016 - IPC E21B47/10 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to production of methane from coal beds and can be used in analyzing productivity of coal beds in coal-methanol wells system. Method includes measurements of gas flow rate, annular gas pressure and level of formation fluid at wellhead. After that dynamic level of formation fluid in vertical well is increased to value providing formation of hydraulic lock in place owing to first horizontal well, with support of annular gas pressure at initial value. Then wells gas flow rate and productivity of coal bed are determined, made by first horizontal well, and total efficiency of coal bed with hydraulic fracturing and coal bed, made by second horizontal well. Then dynamic level of formation fluid in the vertical well is increased again to value providing formation of hydraulic lock at intersection with second horizontal well. Second horizontal well and vertical wells gas flow rate is determined and, consequently, efficiency of formation of second horizontal well and residual productivity of coal bed with hydraulic fracturing (HFT) after flooding. For determination of formation productivity from HFT to flooding from initial fixed total gas flow rate of all wells take obtained flow rate immediately after creation of hydraulic lock and stabilization of gas flow rate of horizontal wells.

EFFECT: easy determination of productivity of formations by gas in coal-methanol wells.

1 cl, 1 dwg