Abstract:
The heavy-oil reservoir in Henan Oilfield is characterized by shallow buried depth,thin oil reservoir and viscosity of crude oil.According to the international and China's screening standards of steam stimulation,most of heavy-oil resources could not be developed by means of conventional steam stimulation.Based on the characteristics of the heavy-oil reservoirs in Henan Oilfield,a series of works of steam stimulation was carried out,including rationally dividing layer series of development,optimizing perforation well section,dynamically adjusting injection-production parameters,assembling stimulation,forcing fluid withdrawal.So,the steam simulation in this kind of shallow and thin heavy-oil reservoirs has achieved successful results in both technology and economy,and a set of perfect recovery program has been set up.In order to further enhance the degree of utilizing heavy-oil resources and the effect of heavy-oil recovery,some new technologies and methods were studied and tested,such as cold heavy-oil production,horizontal fracturing assisted steam flooding technology,hot-water flooding and intermittent steam flooding.The producing reserves rate of heavy-oil resources increased from 8.3 percent to 75 percent by the use of these technologies,and the heavy-oil production of Henan Oilfield was stable in later decade.