新型油基降滤失剂FCL的研制及评价

Development and Evaluation of a New Oil Base Drilling Fluid Filter Loss Reducer

采用α-烯烃与苯乙烯乳液聚合的方法,利用乙酸酐与浓硫酸进行适度磺化,得到一种亲白油的高分子量聚合物,这种高聚物经过进一步氢化反应,制得一种油基钻井液降滤失剂FCL,其在白油中以胶体形式出现,不会破坏钻井液性能,同时这种胶体尺寸能封堵泥饼中的孔隙,从而达到降滤失的效果。性能评价结果表明,其最佳加量为1.5%,在180℃、3.5 MPa的高温高压滤失量为8.4 m L,优于国外同类产品phlips D21;在密度低于1.5 g/cm3时,油基降滤失剂FCL对油基钻井液的流变性影响较小,在高密度油基钻井液中,表现出更高的降切性能,可使密度为2.0 g/cm3的油基钻井液动切力维持在15 Pa以下。

An oil base drilling fluid filter loss reducer, FCL, was developed by hydrogenation of an oleophylic polymer which was synthesized with α-olefin and styrene through emulsion polymerization and sulfonation by acetic anhydride and concentrated sulfuric acid. Treatment of 1.5% FCL in white oil base drilling fluid reduced HTHP(180 ℃) filter loss to 8.4 m L, without evidently affecting the rheology. Compared with other similar oil base mud filter loss reducers, FCL performs much better in filtration control. FCL does not obviously affect the rheology of oil base drilling fluids with density less than 1.5 g/cm3. In oil base drilling fluids with higher densities, FCL increases the viscosity while decreases their gel strengths.