公开(公告)号：US20140076635A1

公开(公告)日：2014-03-20

申请号：US14116222

申请日：2012-05-10

Applicant: BP EXPLORATION OPERATING COMPANY LIMITED

Inventor： Mark Shelton Aston ,  Mary Ann George ,  Christopher Alan Sawdon

IPC: C09K8/36

CPC classification number: C09K8/36 ,  C09K8/34

Abstract: A drilling mud comprising a base fluid in the form of a water-in-oil emulsion comprising droplets of a brine phase dispersed in a continuous oil phase wherein the brine phase has a dissolved salt concentration of at least 2.5 weight % and the emulsion is stabilized with (i) a first polymeric emulsifier that is a block or graft copolymer of the general formula (A-COO)mB, wherein m is an integer of at least 2, A is a polymeric component having a molecular weight of at least 500 and is the residue of an oil-soluble complex mono-carboxylic acid and (ii) a second polymeric emulsifier that is a graft copolymer of a polyvinylpyrrolidone polymer and an alpha olefin selected from the group consisting of C14 to C20 alphaolefins and mixtures thereof and wherein structural units derived from vinylpyrrolidone are present in the graft copolymer in an amount in the range of 40 to 50 mole %.

Abstract translation: 一种钻井泥浆，其包括油包水乳液形式的基础液体，其包含分散在连续油相中的盐水相的液滴，其中所述盐水相具有至少2.5重量％的溶解盐浓度并且所述乳液被稳定 与（i）第一聚合乳化剂，其为通式（A-COO）mB的嵌段或接枝共聚物，其中m为至少2的整数，A为分子量为至少500的聚合物组分， 是油溶性络合物单羧酸的残基和（ii）第二聚合乳化剂，其是聚乙烯吡咯烷酮聚合物和选自C 14 -C 20α-烯烃及其混合物的α-烯烃的接枝共聚物，其中结构 衍生自乙烯基吡咯烷酮的单元以40〜50摩尔％的量存在于接枝共聚物中。