磷酸盐水泥固井技术在LKQ地区X井火烧油层的应用

The Application of Phosphate Cement Slurry Used in Cementing In-situ Combustion Reservoir Section of Well X in LKQ Area

为有效开发稠油资源,TH油田在LKQ地区X井进行注空气火烧吞吐/火驱开发先导试验。该地区主要目的层渗透率高,易产生漏失,引起固井质量问题。通过分析磷酸盐水泥耐高温抗酸蚀机理,决定使用超声强度发展较快的耐高温、耐CO_2腐蚀的磷酸盐水泥浆进行固井作业。该磷酸盐水泥浆由磷酸盐水泥BCM-600S、降失水剂BCF-600L、缓凝剂BCR-600S和消泡剂G603组成。性能评价结果表明,设计的耐高温耐腐蚀磷酸盐水泥浆固化体耐温达到550℃,高温强度长期不衰退,综合性能满足施工要求。X井采用磷酸盐水泥全井封固,封固段优质率达93.8%,固井质量合格。该磷酸盐水泥可以推广应用。

In-situ combustion and fire-flooding have been done by injecting air into the well X in TH oilfield to try to develop the thick oil resources effectively. In this area the reservoir formations have high permeability and mud losses into the formations have occurred frequently before, resulting in poor cementing job quality. Phosphate cement has been chosen for use in well cementing because this cement is resistant to CO2 corrosion and has good high temperature performance, and the strength of the set phosphate cement measured by ultrasonic sound develops faster. The phosphate cementing slurries are formulated with these additives： phosphate cement BCM-600S, filter loss reducer BCF-600L, cementing retarder BCR-600S and defoamer G603. Laboratory evaluation demonstrates that the phosphate cement slurries are resistant to high temperatures to 550 ℃ when set, and their high temperature strength can last for a long time. The whole length of the well X was cemented with the phosphate cement slurries, 93.8% of the hole section has been cemented excellently. The phosphate cement can be used in other cementing operations.