The production from horizontal tight gas wells is affected negatively by the accumulation of liquids in the bottom of the well (i.e., liquid loading), to the point that additional hydrocarbon production is not possible. In this work we propose an artificial lift method for liquid-loaded horizontal wells, in tight gas shale reservoirs, based on intermittent gas lift principles. An experimental loop was built to test a prototype of the system and explore the operating envelope that determines the optimal liquid removal results. Experimental results are presented in terms of the liquid removal capacity of the device, as a function of the gas injection rate and the Eotvos (Eo) number. Liquid removal values (produced liquid volume / stagnant liquid volume) of up to 75%, and a volumetric efficiency (volume of liquid produced / volume of gas injected) of up to 78% was obtained for the lowest Eotvos number tested (12) at the lowest gas injection rate (0.25 cf/min). Both the liquid removal and the volumetric efficiency behaved inversely proportional to the Eo number and the gas injection flowrate. Reducing the ID of the line, proved to be an efficient approach to reduce the Eotvos number. Using this option resulted in better sweep, but in an increase of the frictional pressure drop. The improved liquid sweep effect of the Taylor bubble at lower Eo is related to a larger radius of the Taylor bubble and a change on the shape of its nose.

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