| Title | Laboratory and Field Evaluation of Polyurethane Foam for Lost Circulation Control |
|---|---|
| Authors | Glowka, David A.; Loeppke, Glen E.; Rand, Peter B.; Wright, Elton K. |
| Year | 1989 |
| Conference | Geothermal Resources Council Transactions |
| Keywords | Drilling; USA; California; Sonoma; The Geysers; LCC; LCM; Lost Circulation Zone; Foam; Case Histories; Laboratory Tests; Field Tests |
| Abstract | A two part polyurethane foam has been tested in the laboratory and in the field to assess its utility in controlling lost circulation encountered when drilling geothermal wells. A field test was conducted in the Geysers in January, 1988, to evaluate the chemical formulation and downhole tool used to deploy the chemicals. Although the tool apparently functioned properly in the field test, the chemicals failed to expand sufficiently downhole, instead forming a dense polymer that may be ineffective in sealing loss zones. Subsequent laboratory tests conduced under simulated downhole conditions indicate that the foam chemicals undergo severe mixing with water in the wellbore, which disturbs the kinetics of the chemical reaction more than was previously contemplated. The results indicate that without significant changes in the foam chemical formulation or delivery technique, the foam system will be ineffective in lost circulation control except under vary favorable conditions. |