Synthetic oil-water emulsion drill-in fluid cleanup methods
AssigneeHalliburton Energy Services, Inc.
InventorsJames E. Griffith, Jiten Chatterji, Bobby J. King, Bryan K. Waugh, Patty L. Onan
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Abstract
The present invention provides methods of cleaning up a producing interval of a well bore drilled using a synthetic oil-water emulsion drill-in fluid. The methods basically comprise contacting filter cake and drill-in fluid on the walls of the well bore with three treatment fluids in three stages, the first and second treatment fluids being comprised of water, a filter cake dissolving acid, a mutual solvent and an emulsion penetrating agent. The third treatment fluid is comprised of water, a filter cake dissolving acid and a water wetting surfactant.
Claims20
A method of cleaning up a producing interval of a well bore drilled using a synthetic oil-water emulsion drill-in fluid and having filter cake and drill-in fluid on the walls thereof comprising the steps of:
- (a) contacting said filter cake and drill-in fluid in a first stage with a first treatment fluid comprised of water, a filter cake dissolving acid present in said treatment fluid in an amount in the range of from about 1% to about 7.5% by weight of said water, a mutual solvent for making otherwise insoluble materials soluble in said treatment fluid present in an amount in the range of from about 10% to about 20% by weight of said water and an emulsion penetrating agent present in an amount in the range of from about 10% to about 20% by weight of said water;
- (b) contacting said filter cake and drill-in fluid in a second stage with a second treatment fluid comprised of water, a filter cake dissolving acid present in said treatment fluid in an amount in the range of from about 10% to about 25% by weight of said water, a mutual solvent present in an amount in the range of from about 10% to about 20% by weight of said water and an emulsion penetrating agent present in an amount in the range of from about 10% to about 20% by weight of said water;
- and
- (c) contacting said filter cake and said drill-in fluid in a third stage with a third treatment fluid comprised of water, a filter cake dissolving acid present in said treatment fluid in an amount in the range of from about 10% to about 25% by weight of said water and an effective amount of a water wetting surfactant to change the wettability of said walls of said well bore from oil wet to water wet.
A method of cleaning up a producing interval of a well bore drilled using a synthetic oil-water emulsion drill-in fluid and having filter cake and drill-in fluid on the walls thereof comprising the steps of:
- (a) contacting said filter cake and drill-in fluid in a first stage with a first treatment fluid comprised of water, hydrochloric acid present in said treatment fluid in an amount of about 3% by weight of said water, an effective amount of a metal corrosion inhibitor, a mutual solvent comprised of ethylene glycol monobutyl ether present in an amount of about 15% by weight of said water and an emulsion penetrating agent comprised of a mixture of an alkyl alcohol, an emulsifying agent, a mutual solvent and a co-solvent present in an amount of about 15% by weight of said water;
- (b) contacting said filter cake and drill-in fluid in a second stage with a second treatment fluid comprised of water, hydrochloric acid present in said treatment fluid in an amount of about 15% by weight of said water, an effective amount of a metal corrosion inhibitor, a mutual solvent comprised of ethylene glycol montobutyl ether present in an amount of about 15% by weight of said water and an emulsion penetrating agent comprised of a mixture of an alkyl alcohol, an emulsifying agent, a mutual solvent and a co-solvent present in an amount of about 15% by weight of said water;
- and then
- (c) contacting said filter cake and drill-in fluid in a third stage with a third treatment fluid comprised of water, hydrochloric acid present in said treatment fluid in an amount of about 15% by weight of said water, an effective amount of a metal corrosion inhibitor and an effective amount of a water wetting surfactant to change the wettability of said walls of said well bore from oil wet to water wet.
Dependencies are inferred from the claim text.