Research On Adaptability Of Continuous Gas Lift Drainage And Gas Recovery In Low Pressure Effluent Gas Wells

At present, many gas fields have entered the middle and later periods of production and most wells of those gas fields produce liquid in different extent. Producing liquid will result in the increase of bottom back pressure, aggravation of slippage loss in the well-hole and gas wells are difficult to produce stable. With the continuing reduction of formation pressure, The quantity of wells which producing liquid is increasing and producing method of those wells are changed from flow production to gas recovery technique by liquid unloading process. Artificial gas lift is characteristic of non-physical deterioration, easy-operation and management, large-scale of liquid production capacity and high depth of lifting. This technique is appropriate for the complicated gas wells which producing sand, containing corrosive medium and are deep and is becoming the leading artificial lift method nowadays.Gas lift is inapplicable to low pressure gas wells for the result that it will cause back pressure. But at present, there is no specific formation pressure index to decide whether gas lift is applicable to a gas well. In other word, we cannot judge promptly whether gas lift is applicable to a gas well by the well's formation pressure.In this paper, the author has made a large number of simulating for gas lift of various situations Limited. Through a large amount of data, the author has concluded the minimum formation pressure coefficient in different situations for gas lift. Due to the actual development of gas wells. The best measure is liquid production and gas production, so the final positioning in different liquid yield and gas production can be used in the gas lift process required the lowest formation pressure coefficient. And to draw the lowest formation pressure coefficient, and analysis of its impact on the adaptability of the gas lift, and summed up some rules.The research contents of this paper can solve the predicament that there is no specific formation pressure index to decide whether gas lift is applicable to a gas well, and for different pipe diameter, different gas injection depth were simulated which can make the field application of gas lift for low pressure gas wells more convenient.