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基于钻井液技术所面临的油气层保护，安全快速钻井方面的严格要求。从优选处理剂入手，根本上能够解决页岩水化、油层保护、环保等方面的问题，研制了一种新型聚合醇钻井液。由于聚合醇易于生物降解、利于环保、保护油层等特点，很快引起了人们的关注。聚合醇的作用机理表现为：聚合醇具有浊点效应，当温度降低到浊点温度以下时，聚合醇开始溶解，而温度高于浊点温度时，从水中析出，形成憎水膜，吸附在页岩表面，抑制页岩水化分散的作用；聚合醇与无机盐具有协同效应，起到了抑制页岩水化分散，稳定页岩的作用；聚合醇可增大滤液的粘度、降低滤液的化学活性，抑制页岩水化分散。进行了聚合醇对钻井液的流变性、热稳定性、抑制性等方面的研究，实验结果表明聚合醇的浓度在3%时，所研制的聚合醇钻井液具有很好的热稳定性、抑制性与较好的流变性，能够满足钻井施工的要求。

RESEARCH ON A NOVEL POLYGLYCOLS DRILLING FLUID SYSTEM 2)

According to the strict demands of drilling fluid techniques confronting with reservoir protection, safe and fast drilling, and starting with optimal selecting drilling fluid additives to thoroughly solve the problems in the respects of shale hydration, reservoir protection and environment protection, a novel polyglycols drilling fluid is researched, which quickly catches people’s attention because the polyglycols are prone to biological degradation, benefit to environment protection and reservoir protection. The action mechanism of the polygycols is of cloud point effect, i.e. when the temperature is lower than cloud point temperature, polyglycols begin with dissolution; when the temperature is higher than cloud point temperature, the polyglycols begin with precipitation to form hydrophobic film, adsorbed to the shale surface and inhibit the hydration and dispersion of the shale. The polyglycols can increase filtrate viscosity and reduce filtrate activity to stabilize the shale. In this paper, the rheological behavior, thermal stability and inhibition property of the polyglycols drilling fluid are researched and all of them are very good when the concentration of polyglycols is 3% so as to meet the need of drilling operation.