保护石炭系气层的固井技术

^WELL CEMENTING TECHNIQUES OF PROTECTING CARBONIFEROUS GAS RESERVOIRS

固井作业对地层的损害不仅同钻井液引起的损害有相似的原因和规律，也有其特殊的作用机理和损害。水泥浆对川东石炭系碳酸盐岩气层的损害主要表现为滤液和固相颗粒侵入地层，引起地层泥膜及化学反应，堵塞裂缝和孔隙，使油、气通道面积缩小。文章介绍了川东石炭系碳酸盐岩地层的特征及固井水泥浆对油气层造成的各种伤害，并介绍了适合川东保护油气层固井的水泥外加剂、水泥外加剂配方及保护产层的固井方法等。

hat well cementing operation does damages to strata is not only of the same reasons and laws as those done by drilling fluid but also is of its special actions and mechanisms. The damages done by cementing fluid to the carbonate rock gas reservoirs in Chuandong Carboniferous display that oil-gas passages become narrow to plug fractures and pores, which is caused by stratigraphic mud membrances and chemical reactions as filtrate and solid perticls intrude into strain. The characteristics of the carbonate rock strsta in Chuandong Chrboniferous, the various damages done by cementing fluid to oil-gas reservoirs, cement additive being suitable to the well cementing of protecting oil-gas reservoirs in Chuandong. the well cementing method of protecting payzones are introduced.