论文部分内容阅读
Sanand油田是印度在过去的12年中唯一一个全油田范围内实施聚合物驱的油田。该油田发现于1962年,并于1969年开始进行工业性开采。由于较大的流度比和以溶解气为主要驱动方式,使得预测采收率很低,大约占原油地质储量的15%左右。该油田采用了聚合物驱作为提高采收率的一种措施来提高原油采收率。1985年,该油田实施一个反五点法的聚合物先导性试验。因试验效果显著,1993年该油田将注聚项目推广到一个大区块,并于1995年在全油田进行了方案实施。到2007年7月,油田的采收率大约为24%,含水率为68%。注聚将持续到2013年随后进入后续水驱阶段,预计到2020年,该油田的采收率大约为36%,含水率为77%。长时间保持聚合物溶液和后续水的性质对于实施聚驱项目的专家来说是一个挑战,而且它对聚驱项目的成功起着关键性作用。因此,有必要对整个过程进行持续性监测,来确定这个方案实施的有效性并使其按照正常的程序进行。监测方面包括以下过程:①生产井的动态;②注入系统内不同点处聚合物的流变性;③影响聚合物黏度的水质和其他参数,如溶解的氧气、细菌活性等;④注入井底的流速、压力及其动态。本文着重提出了保持注入聚合物溶液和后续水质量以及其他工艺参数的措施,并指出它是如何帮助聚合物提高采收率技术在Sanand油田发挥作用的。
Sanand Oilfield is the only oilfield in India that has implemented polymer flooding in the last 12 years in a full oilfield. The field was discovered in 1962 and began industrial mining in 1969. Due to the large flow ratio and dissolved gas as the main driving mode, the predicted recovery rate is very low, accounting for about 15% of the crude oil geological reserves. The field uses polymer flooding as a measure to increase oil recovery to enhance oil recovery. In 1985, the field implemented an inverse five-point polymer pilot test. Due to the remarkable test results, the project was extended to a large block in 1993 and was implemented in all the fields in 1995. By July 2007, the oil recovery was about 24% with a water cut of 68%. Injection will continue into later stages of waterflooding until 2013 and is expected to have a recovery of about 36% and a moisture content of 77% by 2020. Maintaining properties of polymer solutions and subsequent water for extended periods of time is a challenge to experts in implementing the poly flooding project and it is crucial for the success of the poly flooding project. Therefore, there is a need for continuous monitoring of the entire process to determine the effectiveness of the program and to follow its normal procedures. The monitoring includes the following processes: (1) Production well dynamics; (2) Rheology of polymers injected at different points in the system; (3) Water quality and other parameters that affect polymer viscosity such as dissolved oxygen and bacterial activity; Flow rate, pressure and their dynamics. This article highlights measures to preserve the injected polymer solution and subsequent water quality and other process parameters and points out how it helps polymer enhanced oil recovery techniques play a role in the Sanand field.