Loose sandstone heavy oil reservoir is characterized as shallow buried,low temperature,poor lithology and loose cementation. It employs high-velocity water flow to conduct gravel packer completion,which result to leakage of completion fluid. Therefore a sealing weak gel completion fluid for loose sand depleted reservoir is developed. The recipe is as followed:filtering sea water+0.25%Na2CO3+0.7%FCNQ+2.0% filtrate reducer;Gel breaking liquid recipe:filtering sea water+3% new gel breaker +3%KCl. The reduction rate of leakage is greater than 90% when the fluid is applied,and core permeability recovery value comes to 86.8% with good reservoir protection. The fluid has strong suspension stability and good compatibility with later work fluids. It proves to be successful in SZ36-1 block,Bohai Oilfield.%疏松的砂岩稠油油藏储层具有的特征如下:温度低、埋藏浅、胶结疏松以及成岩性差等.该类油藏大都采用高速水流进行砾石充填完井,这就导致了完井液大量漏失等问题.基于以上考虑,在室内试验室研究出了适合疏松的砂岩稠油油藏储层的封堵型弱凝胶完井液.弱凝胶封堵配方:0.7%流型调节剂+2.0%降滤失剂+0.25%Na2CO3+海水.破胶液配方:3%新型破胶剂+3%KCl+海水.该体系使用后漏失降低率大于90%,解堵后岩心的渗透率恢复值达到86.8%,储层保护效果好,并且悬浮稳定性强,与后续工作液的配伍性好.渤海海域上绥中36-1区块广泛应用了本完井液体系并能很好地解决工程实际问题.
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