LD27-2油田稠油热采井固井技术难点与对策

以LD27-2油田作为渤海代表性的整装稠油油田,按固井主要涉及的固井化验、固井工程以及固井设备这3个板块,对稠油固井作业中遇到的难点进行了分析。优选出满足350℃稠油开采的水泥浆体系,并结合体系及地层压力特点采取了领尾浆双浆柱结构和使用封隔器等的工程技术措施,针对海洋平台空间受限,灰罐罐容不足的问题,采取了拖轮固井的办法。试验井固井后声波幅度测井(CBL)数据显示,水泥全井段封固,封固质量完全满足要求。该井自开泵一年以来生产状况良好,最高分配日产油74 m~3。由此,形成了新的稠油热采井固井技术体系,指导今后海洋稠油油田固井作业。

Difficulties in cementing technology for heavy oil thermal recovery wells LD27-2 Oilfield and relevant solutions

The LD 27-2 Oilfield is taken as a representative mono-block heavy oil field in Bohai region. Analysis was conducted to the difficulties in cementing job in heavy oil wells in terms of cementing test, cementing engineering and cementing equipment. A cement slurry system is chosen which can be used in heavy oil production under 350 °C. Engineering techniques such as double-slurry column structure of lead slurry and tail slurry and the use of packers were adopted in combination with the formation pressure characteristics and the cement slurry system. In view of limited space and insufficient cement tank capacity on offshore drilling platforms, tugboat was used in cementing. After cementing job was finished in the test well, the CBL data shows that the entire hole was filled with cement and cementing quality was fully acceptable. This well has been producing favorably for one year since pumping started and its maximum daily oil production was 74 m3. Hence, a new cementing system has been developed for heavy oil thermal production wells, which can provide guidance for cementing jobs in offshore heavy oil fields.