海洋天然气水合物地层钻探钻井液低温流变性能研究

海洋天然气水合物赋存于低温和高压环境条件,以分解抑制法钻进水合物地层,常通过降低钻井液的温度来抑制水合物的分解,所以要求钻井液具有良好的低温性能。对甲酸盐海水钻井液和聚合醇海水钻井液在不同低温条件下的流变性能进行了探讨。结果表明：钻井液处理剂和水合物抑制剂均对钻井液的低温流变性能有不同程度的影响。提出在研究海洋天然气水合物地层钻探钻井液时,应合理选择钻井液体系和处理剂,确保钻井液在低温条件下具有良好的流变性能。

Research on the Low Temperature Rheology Property of Drilling Fluids for the Offshore Gas Hydrate Exploration

Offshore gas hydrates is hosting in the environmental condition of low temperature and high pressure. Drilling in hydrate formation with decomposing inhibition technology, drilling fluid temperature is often lowered to inhibit hydrate dissociation, so low temperature performance of drilling fluid is important. Study was made on the rheology property of formate seawater drilling fluid and polymeric alcohol seawater drilling fluid at different low temperatures; the result showed there was certain degree influence on low temperature rheology property of drilling fluid by both drilling fluid additive and hydrate inhibitor. Reasonable selection on drilling fluid system and additive should be taken into account in the study on drilling fluid for offshore gas hydrate drilling to ensure its good rheology at low temperature.