Many ASP flooding method have been tested in Daqing oil field. After the success of polymer flooding in Daqing oil field, four alkaline- surfactant-polymer flooding pilot tests have been conducted in order to: increase oil recovery further and provide technical and practical experience for expanding the ASP pilot. From four ASP pilot test, the following conclusions can be made: ASP flooding pilot can form oil banks, greatly lower water cut, increase the oil production as well as the oil recovery. The incremental oil recovery was about 20% over water flooding.
To further confirm the effect of large well spacing on EOR, three ASP field test with a large well spacing (200 to 250 m) have been tested in Daqing oil field. The commercial pilot tests result shows that the ASP flooding can increase recovery 20% more than water flooding.
The paper collected 12 pilot test date of industrial surfactant flooding in China, It Has been evaluated that each pilot test successful or not cleanly. Also discussed problem. Emphasize indicated that design project of combination flood, surfactant kind, structure, slag design and size and a scale of production were developed key. Decreased cost were also important task. Alkaline-Surfactant-Polymer (ASP) flood processes have been increasingly applied in the oil fields due to their high ultimate oil recovery. However, a major technical challenge is how to significantly reduce the amount and the cost of chemicals used such that ASP floods can become cost-effective as well. Field applications show that the concentrations of alkali, surfactant and polymer remain relatively high in the produced fluids of ASP floods. Thus, successful reuse of these chemicals can substantially reduce the capital cost and the environmental impact. Also re-injection of the produced chemicals is conducted for further enhancing oil recovery.
This paper have discuss problems of ASP flooding:
Emulsions occurred in some producers of the larger well spacing field test, the test shows that by using a specific kind of de-emulsifier commonly used in the field, the emulsions in the produced fluid are not to be broken because adding hard alkali.
This paper provides practice basis for the enlarging of ASP flooding..At present, most of ASP flooding are successful, But alkaline/com-oil carboxylates/polymer and foam/alkaline/surfactant/polymer flooding are not successful to be used to Daqing oilfield. The cost of chemicals (alkaline/surfactant/polymer) per barrel incremental oil is $11 to $15.The total cost of per barrel incremental oil is $15 to $30. The incremental recovery is 20% OOIP over water flooding.