弱凝胶无固相钻井液破胶实验研究

Experimental study on gel breaking of weak gel solid-free drilling fluid

弱凝胶无固相钻井液体系在使用过程中易在井壁形成致密泥饼或在正压差作用下进入地层,吸附在储层孔隙骨架颗粒上,造成储层渗透率降低、油气渗流通道受阻、油气井产能下降。室内实验优化得到复配破胶剂,从破胶效果、破胶时间、储层抑制效果及腐蚀性等方面对复配破胶剂进行室内评价,评价结果表明该破胶剂各项指标均满足现场要求。

Weak gel solid-free drilling fluid system is easy to form dense mud cake in the well wall during the use process or enter the formation under the action of positive pressure difference, adsorbing on the skeleton particles of the reservoir pore, causing the reservoir permeability to decrease and the oil and gas seepage channel is blocked and the production capacity of oil and gas wells is declining.In this paper,a compound gel breaker was optimized by laboratory experiments.The internal test was evaluated from the gel breaking effect, gel breaking time, reservoir inhibition effect and corrosivity.The evaluation results showed that the gel breaker can meet the site requirements.