Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Well treatment to remove permeability block

Patent ·
OSTI ID:6951501
This is a method of restoring production from wells from which production has decreased or stopped altogether due to the formation of an emulsion block around the well bore wherein a viscous emulsion of oil and water is formed through which neither connate water nor oil can penetrate. The treating surfactants consist of an injected emulsion to break the emulsion in the formation. The injected emulsion consists of a mixture of nonionic, water-soluble surfactant and an anionic surfactant with between 1-8 volumes of oil to each volume of water. The cloud-point temperature range of the nonionic surfactant will be from 0-20$F lower than the formation temperature. The ratio of the nonionic surfactant and the anionic surfactant is from 0.25-4 volume % relative to the volume of the water in the emulsion. A film-strengthening agent in the amount of 0-4% by weight of water may be added. (6 claims)
Assignee:
TUL; EDB-81-030810
Patent Number(s):
US 3185217
OSTI ID:
6951501
Country of Publication:
United States
Language:
English