The Application Of Sulfonate In The Thermal Recovery Of Heavy Oil

Major factors which influence the steam injection profile are steam overlaying and high-permeability zones during steam flooding and cyclic steam injection. When the above phenomena occur, a large amount of steam will flow into high-permeability zones and the top of the reservoir during cyclic steam injection and high-permeability zones or channeling will be formed between injectors and producers during steam flooding. Therefore, steam injected later can't flow into medium and low permeability zones and sweeping volume and ultimate recovery factor will be influenced.Foam can be used for decreasing steam mobility in the process of steam foam injection to increase the pressure gradient of the swept area, force steam to divert into the unswept zones with medium and lower permeability, improve the injection profile of zones and increase the sweeping efficiency of steam during steam flooding and cyclic steam injection.As sulfonate additive has the features of surfactant, has an amphiphilic structure and its hydrophilicity is stronger than its lipophilicity, it is helpful to the formation of oil-in-water emulsion and helpful to fluid flowing back. After sulfonate additive is injected, for rocks, strong hydrophilicity is turned into weak hydrophilicity, meanwhile, sulfonate additive can decrease interfacial tension and has good foamability and it's useful to flowing back of formation fluid.Surfactants, such as high-temperature foaming agent, are used to adjust the steam injection profile of thermal recovery wells of heavy oil during thermal recovery of heavy oil wells which is being tested industrially abroad. Most of steam added with foam tests indicate that oil can be incremented, but working temperature must be lower than 200℃.In view of conditions for heavy oil in Liaohe Oilfield, such as more than 1000m of most buried depths and 350℃of steam injection temperature, a high-temperature foaming surfactant system with high-carbochain alkyl benzene sulfonate or alkyl toluene sulfonate as the main body added with additives of aids, solvents and stabilizing agents is being developed by screening surfactant samples to meet the field requirements of the process of profile control by injecting steam-foam...