Producing by Polymer Flooding more than 300 Million Barrels of Oil,What Experiences Have Been Learnt?

In 1996, Daqing Oil Field started industrial scale polymer flooding. The production by polymer flooding since then has rapidly increased. The annual production by polymer flooding in year 2001 was more than 70 million barrels (bbl), cumulative production more than 300 million bbl and more than 3 thousand wells are on polymer flooding. Much experience has been learnt on large scale polymer flooding in these 6 years, including: actual recovery in the field; major factors that influence the recovery and methods to increase the recovery; measures to obtain a uniform polymer flood front; and how to lower the costs of producing crude oil by polymer flooding.