Composition of Wellbore Cleaning Agent

Abstract

A cleaning agent, which comprises a mutual solvent, a carrier fluid, a nonionic surfactant and another nonionic surfactant as co-surfactant. The cleaning agent can be used, for example, to clean oil and water based drilling mud and water-wet the surface.

What is claimed is: 
     
         1 . A wellbore cleaning agent comprising a mutual solvent, a carrier fluid and a surfactant, and another surfactant as a co-surfactant. 
     
     
         2 . A wellbore cleaning agent composition as claimed in  claim 1  wherein the cleaning agent comprises a surfactant or a mixture of surfactants, which have HLB value about 10.0 to about 11.9. 
     
     
         3 . A wellbore cleaning agent composition as claimed in  claim 1  wherein the cleaning agent comprises a co-surfactant or a mixture of co-surfactants, which have HLB value about 12.0 to about 15.0. 
     
     
         4 . A wellbore cleaning agent composition as claimed in  claim 1  wherein the cleaning agent comprises a mutual solvent from the group of ethylene glycol monobutyl ether, propylene glycol monobutyl ether, ethylene glycol, propylene glycol, derivatives thereof or combinations thereof. 
     
     
         5 . A wellbore cleaning agent composition as claimed in  claim 1  wherein, the cleaning agent comprises a carrier fluid the group of isopropyl alcohol, n-propanol, n-butanol, tort-butanol, n-pentanol, 2-ethyl-hexanol, derivatives thereof or combinations thereof. 
     
     
         6 . The composition of  claim 2  wherein the surfactant comprises anionic, cationic zwitterionic and nonionic surfactant, or combinations thereof. 
     
     
         7 . The composition of  claim 3  wherein the co-surfactant comprises anionic, cationic zwitterionic and nonionic surfactant, or combinations thereof. 
     
     
         8 . The composition of  claim 2  wherein the nonionic surfactants comprise alkylphenol ethoxylate, alcohol ethoxylate, polyoxypropylene glycols, polyoxyethylenated mercaptans, fatty acid ester, sorbitol ester, alkanolamides, tertiary acetylenic glycols, polyoxyethylenated silicones, alkylpolyglycosides, or combinations thereof. 
     
     
         9 . The composition of  claim 3  wherein the nonionic surfactants comprise alkylphenol ethoxylate, alcohol ethoxylate, polyoxypropylene glycols, polyoxyethylenated mercaptans, fatty acid ester, sorbitol ester, alkanolamides, tertiary acetylenic glycols, polyoxyethylenated silicones, alkylpolyglycosides, or combinations thereof. 
     
     
         10 . A wellbore cleaning agent composition as claimed in  claim 1  wherein cleaning agent comprises from about 5% to 60% by weight of a mutual solvent, about 10% to 50% by weight of a surfactant, about 10% to 50% by weight of a co-surfactant and about 5% to 30% by weight of a carrier fluid. 
     
     
         11 . A wellbore cleaning agent composition as claimed in  claim 1  wherein the cleaning agent comprises water or brine. 
     
     
         12 . A wellbore cleaning agent composition as claimed in  claim 1  wherein the cleaning agent comprises a flocculating agent or mixtures thereof. 
     
     
         13 . A wellbore cleaning agent composition as claimed in  claim 1  wherein the cleaning agent comprises an organic solvent or a mixture of organic solvents. 
     
     
         14 . A wellbore cleaning agent composition as claimed in  claim 1  wherein the cleaning agent comprises a corrosion inhibitor or a mixture of corrosion inhibitors. 
     
     
         15 . A wellbore cleaning agent composition as claimed in  claim 1  wherein the cleaning agent comprises a weight agent or a mixture thereof. 
     
     
         16 . A wellbore cleaning agent composition as claimed in  claim 1  wherein the cleaning agent comprises a viscosifier or a mixture of viscosifiers.