Liu, He (Research Institute of Petroleum Exploration and Development, PetroChina) | Yang, Siyu (Research Institute of Petroleum Exploration and Development, PetroChina) | Wei, Chenji (Research Institute of Petroleum Exploration and Development, PetroChina) | Yao, Zixiu (Research Institute of Petroleum Exploration and Development, PetroChina) | Ye, Peng (Daqing Oilfield Limited Company, PetroChina)
Daqing oilfield is the largest chemical flooding oilfield in the world. The polymer flooding can enhance oil recovery by 10-15%, while the ASP flooding can enhance oil recovery by over 20%, which is 1.5 times more efficient than the polymer flooding. By the end of 2016, there are 31529 chemical flooding wells, which cover the already proved reserves of more than 1 billion tons. These wells have had cumulative oil production of 0.2 billion tons, and have production more than 10 million tons each year since 2001, thus playing an important role in the production of Daqing Oilfield.
Dynamic monitoring, as an important part for oilfield development, aims to acquire the dynamic and static information in oilfield development, and to provide data for oilfield development dynamic analysis and adjustment by means of testing, logging, coring and analyzing. Since chemical flooding is different from water flooding in oil displacement mechanism, oil-water migration and development process, some indexes in chemical flooding process are especially significant, which are directly related to the development effects, and require timely and dynamic monitoring. Because of the high viscosity of chemical flooding fluids, the monitoring techniques based on the radioactive isotope carrier method of water flooding is not suitable due to problems such as serious contamination and no even dispersion. Therefore, on the basis of tracer monitoring technique for water flooding wells, chemical injection profile logging technique based on electromagnetic flowmeter, oxygen activation and tracer correlation is formed for high viscosity fluids, and has been applied in Daqing Oilfield in more than 4000 wells. This technology could guide dynamic analysis and tracking adjustment, and could have further development of continuous fluid monitoring chemical flooding, and then expand the electromagnetic exploration techniques into the chemical flooding fluid description.