Patent · US Expired

Surfactant oil recovery process usable in high temperature, high salinity formations

US4077471A · kind A · utility

175Cited by
10References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 1, 1976
Grant dateMar 7, 1978
Priority date
Expiry dateDec 1, 1996

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S507/936
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Many petroleum formations contain water having high salinity and/or high concentrations of divalent ions such as calcium or magnesium dissolved therein, and are additionally at temperature from about 70.degree. F. to about 300.degree. F. Most surfactants suitable for use in oil recovery operations are either ineffective in high salinity or high hardness waters, or cannot tolerate the higher temperatures encountered in many such formations. An aqueous fluid containing a water soluble alkylpolyalkoxyalkyl sulfonate or alkylarylpolyalkoxyalkyl sulfonate and a water-insoluble polyethoxylated aliphatic alcohol or polyethoxylated alkylphenol nonionic surfactant is effective in formations containing water whose salinity is from 70,000 to 220,000 parts per million total dissolved solids and also having temperatures as high as 300.degree. F. The fluid is phase stable over a wide range of formation temperatures and water salinities and hardness values.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.