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U.S. Department of Energy
Office of Scientific and Technical Information

Timing the deposition of an asphalt plugging material from an asphalt-cationic emulsion

Patent ·
OSTI ID:6543698
A mixture of urea and urease provides a timed breaking of a cationic asphalt emulsion when the emulsion is used in plugging a subsurface formation. The composition is especially useful in plugging low temperature formations. The composition is a pH-increasing reactant, the higher pH breaking the emulsion. (11 claims)
Assignee:
Shell Oil Co.
Patent Number(s):
US 4002204
OSTI ID:
6543698
Country of Publication:
United States
Language:
English