【摘要】 目前使用的低密度钻井液都含有油或气,含油的密度最低只能降到0.85g/cm3,同时对环境污染严重;含气的脉冲信号衰减严重,在需使用MWD时不能使用。试验了一种空心微珠玻璃球钻井液减轻剂。该剂为一种硅硼酸钙盐,化学性能稳定,不溶于水和油,具有不可压缩性,对环境无污染,其粒径分布范围为0.5~125μm,其中90%分布在8~85μm之间,因此不影响固控设备的使用。在普通水基钻井液中加入20%以内的该减轻剂,并配合使用架桥粒子制得的低密度钻井液性能在可接受范围内,具有全井密度均匀、形成的泥饼润滑性好的特点;其中密度为0.32g/cm3的产品在1700m井深以内可以使用,密度为0.38g/cm3的产品在2800m井深以内可以使用。更多还原

【Abstract】 Most of the low density muds used at present contain oil and/or gas. The lowest mud density that can be achieved is 0.85 g/cm3 when oil is used to formulate the mud and this mud has a severe negative effect on the environment. When gas is used, MWD may not be used because of the attenuation of the pulse signal when gas is present. In our laboratory research, a hollow glass micro-sphere is used formulating the required low density mud. This micrpo-sphere is a calcium silicate borate, and is chemically stable in both oil and water. It is incompressible, and environmentally friendly. The size distribution of the spheres is in a range of 0.5-125 microns, and 90% of the spheres have diameters ranging from 8-85 microns. This means that the spheres will not be screened out of the mud by the shale shaker or block the screens. A water base mud containing 20% (Wt) of the hollow glass micro-sphere and a bridging agent has an acceptable low density. The whole mud in a well has a uniform density and the mud cake formed has good lubricity. A hollow glass micro-sphere having a density of 0.32 g/cm3 can be used in a depth of less than 1700 m, and a hollow glass micro-sphere having a density of 0.38 g/cm3 can be used in a depth of less than 2800 m.更多还原