Improve salt tolerance

Capability to enhance salt introduced in the molecular structure an alkyl polyoxyalkylene nonionic, anionic or cationic molecule to introduce a hydrophilic group, or introducing the same or different one or more anionic hydrophilic group. Such as alkyl phenol Oil machine and alkylphenol sulfonate ether disulfonate, two types of new efficient oil surfactant, cosurfactant they need to form a stable microemulsion, can be used in salinity from 4% to 30% of the reservoir flooding. 2 Enhanced heat resistance may be introduced in the molecular structure nonionic groups (e.g., polyoxyethylene polyoxypropylene ethyl or propyl? Oxyethylated alkylphenol group, etc.) characteristic structure, combined with other suitable additives , will effectively improve the heat resistance flooding. 3 is optional and low cost first surfactant, and machine for pellets. Lower cost surfactants are mainly three types: lignin sulfonates? Without added surfactants synergists and carboxylate surfactants. Since lignin is not lipophilic, the modification required to introduce lipophilic groups, such as alkylated? Etherification reaction or a substituted alkyl may be introduced to obtain a lower cost modified lignosulfonate products, can make the target sample of crude oil and the interfacial tension between oil displacement reaches 10-2mN / m or less. Water-soluble carboxylic acid salts generally worse, the need to introduce hydrophilic groups. If Chevron Research Co. Invented a salt of the oligomeric surfactant.