Since 2007, Chinese oil company Sinopec has been injecting CO2 for EOR in abandoned water-flooded oil reservoirs and low permeability oil reservoirs in the Zhongyuan Oilfield. They have been developing and improving techniques for CO2 capture, CO2 injection, reservoir storage and CO2 storage monitoring. The projects in the cities of Puyang, Xinxiang and Kaifeng of Henan Province have reached annual capture capability of one million tons CO2 to date. The CO2 injection achieved to 160,000 tons have been injected annually, with a total injection of around 0.5 million tons and an increase in production of around 0.1 million tons crude oil.
In the past decade, Sinopec has established 17 industry standards and applied for 40 patents (among which 33 products were granted). Further, Sinopec has been invited to participate in relevant summits held by ASEAN countries and delivered a keynote speech at international conferences held by NDRC. In the meantime, Sinopec has conducted two seminars focusing on improving efficiency of CO2 capture and promoting popularization of techniques in 5 oilfields, including fields owned by Yanchang Petroleum.
The CO2 EOR and storage of abandoned water-flooded oil reservoirs developed by Zhongyuan Oilfield drew attention to CO2 storage from other enterprises in the Henan Province, thereby enhancing exploration of poor-quality reservoirs and stimulating a new mode of CO2 storage and utilization through coordination of enterprises from areas of capture, utilization and mechanical manufacture.
Figure 1. CO2 Injection Site
Figure 2. CO2 -EOR Well