海上高含水稠油油藏治理对策研究

Study on countermeasures for offshore high water cut heavy oil reservoirs

为探究海上高含水稠油油藏的治理方法,针对海上稠油油藏储层物性好、水利能量充足、单井产液量高、原油黏度高和油井高含水等特点,通过建立井组地质模型,采用油藏数值模拟方法,研究不同驱替开采方式和注采参数对抑制、延缓底水锥进的效果。研究发现:(1)针对海上稠油油藏的敏感性分析,注入介质>地层倾角>渗透率韵律>级差;(2)0.2%活性水黏度较地层水高2倍,能在储层中形成0.07 km^(2)平面驱替,提高注入活性水和底水波及系数3.88%;增油18.75×10^(4) m^(3);(3)综合多种治理方案,对区块南部剩余油富集区进行加密水平井部署同注活性水对比产出投入比高0.2,将平均井距缩减至350 m,最终采出程度达到36.64%。以上成果可为后期同类油藏的治理对策提供参考。

In order to explore the treatment methods for offshore high water cut heavy oil reservoirs,aiming at the characteristics of offshore heavy oil reservoirs such as good physical properties,sufficient hydraulic energy,high single-well liquid production,high crude oil viscosity and high water cut oil wells,the well group geology is established.The model uses reservoir numerical simulation methods to study the effects of different displacement production methods and injection-production parameters on the suppression and delay of bottom water coning.The study found that:(1)The sensitivity analysis for offshore heavy oil reservoirs is injection medium>formation dip>permeability rhythm>level difference;(2)0.2%active water has a viscosity twice higher than formation water and can be in the reservoir form a 0.07 km 2 plane displacement,increase the injected active water and bottom water sweep coefficient by 3.88%;increase the oil by 18.75×10^(4 )m^( 3);(3)Comprehensive multiple treatment schemes,deploy the infill horizontal wells in the remaining oil-rich area in the southern part of the block.The active water is 0.2 higher than the output input ratio,which reduces the average well spacing to 350 m,and the final recovery rate reaches 36.64%.The above results can provide a reference for the later treatment of similar reservoirs.