LIU Gang, WANG Junheng, WANG Danling, et al. Development and reservoir adaptability evaluation of a high temperature resistant plugging agent: tannin extract[J]. Petroleum Reservoir Evaluation and Development, 2021, 11(3): 452-458.DOI:
There are several problems in the high temperature resistant plugging agent used in steam flooding of heavy oil reservoirs to control steam channeling
such as low strength and poor long-term stability. So
it is urgent to develop a new type of high temperature resistant plugging agent to promote on-site application. In order to solve the technical problems caused by strong inter-layer heterogeneity of the heavy oil reservoirs in District 9-6 of Qigu Formation in Xinjiang Oilfield
including severe steam channeling and poor foam flooding effects
a plugging agent system suitable for high temperature reservoirs and composed of sulfonated tannin extract
cross-linking agent and accelerant has been developed. By the static evaluation experiment
it is found that the optimized formula of the plugging agent is as follows: 0.6 % sulfonated tannin extract + (2.0 % ~ 2.5 %) aldehyde cross-linking agent Ⅰ +(1.0 % ~ 2.0 %) phenol cross-linking agent Ⅱ +(0.05 % ~ 0.06 %) accelerant. The evaluation of reservoir adaptability shows that the strength of the plugging agent remains above level H after 30 days of aging at the reservoir temperature
and the plugging efficiency is above 94 %. It has laid a foundation for the field application of steam channeling control technologies in the heavy oil reservoirs of District 9-6 of Qigu Formation in Karamay Oilfield.