Methods and compositions for sealing pipe and forming barriers in well bores

Abstract

The present invention provides methods and compositions for sealing pipes or forming barriers in well bores. A hardenable, low density sealing composition of the invention basically comprises a hardenable furan liquid resin mixture, an organosilane coupling agent, a cationic surfactant and hollow microspheres.

What is claimed is:  
     
         1 . A method of sealing pipe or forming a barrier in a well bore comprising the steps of: 
 (a) preparing or providing a hardenable, low density sealing composition comprising a hardenable furan liquid resin mixture, an organosilane coupling agent, a cationic surfactant, and hollow microspheres;    (b) placing said sealing composition in said well bore; and    (c) allowing said sealing composition to harden into an impermeable mass.    
     
     
         2 . The method of  claim 1  wherein said hardenable furan liquid resin mixture comprises a 2-furanmethanol homopolymer present in said mixture in an amount in the range of from about 55% to about 60% by weight thereof and furfuryl alcohol present in said mixture in an amount in the range of from about 40% to about 45% by weight thereof.  
     
     
         3 . The method of  claim 1  wherein said hardenable furan liquid resin mixture is present in said sealing composition in an amount in the range of from about 10% to about 50% by weight thereof.  
     
     
         4 . The method of  claim 1  wherein said organosilane coupling agent is selected from the group consisting of N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-gylcidoxypropyltrimethoxysilane and n-beta(aminoethyl)-gamma-aminopropyltrimethoxysilane.  
     
     
         5 . The method of  claim 1  wherein said organosilane coupling agent is N-2-(aminoethyl)-3-aminopropyltrimethoxysilane.  
     
     
         6 . The method of  claim 1  wherein said organosilane coupling agent is present in said sealing composition in an amount in the range of from about 0.1% to about 3% by weight thereof.  
     
     
         7 . The method of  claim 1  wherein said cationic surfactant is selected from the group consisting of ethoxylated nonyl phenol phosphate ester, C 12 -C 22  alkyl phosphonates and mixtures of one or more cationic surfactants and one or more non-ionic surfactants.  
     
     
         8 . The method of  claim 1  wherein said cationic surfactant is a C 12 -C 22  alkyl phosphonate.  
     
     
         9 . The method of  claim 1  wherein said cationic surfactant is present in said sealing composition in an amount in the range of from about 0.1% to about 10% by weight thereof.  
     
     
         10 . The method of  claim 1  wherein said hollow microspheres are selected from the group consisting of hollow mineral glass spheres, hollow silica-alumina spheres, glass spheres and ceramic spheres.  
     
     
         11 . The method of  claim 1  wherein said hollow microspheres are mineral glass spheres.  
     
     
         12 . The method of  claim 1  wherein said hollow microspheres are present in said sealing composition in an amount in the range of from about 5% to about 50% by weight thereof.  
     
     
         13 . The method of  claim 1  wherein said sealing composition further comprises a solvent or diluent selected from the group consisting of 2-butoxy ethanol, butyl acetate, furfuryl acetate and mixtures thereof.  
     
     
         14 . The method of  claim 13  wherein said sealing composition is furfuryl acetate.  
     
     
         15 . The method of  claim 13  wherein said solvent or diluent is present in said sealing composition in an amount in the range of from about 5% to about 60% by weight thereof.  
     
     
         16 . The method of  claim 1  wherein said sealing composition further comprises a dispersing agent selected from the group consisting of naphthalene-sulfonate-formaldehyde condensate, acetone-formaldehyde-sulfite condensate and glucano-delta-lactone.  
     
     
         17 . The method of  claim 16  wherein said dispersing agent is naphthalene-sulfonate-formaldehyde condensate.  
     
     
         18 . The method of  claim 16  wherein said dispersing agent is present in said sealing composition in an amount in the range of from about 0.1% to about 10% by weight thereof.  
     
     
         19 . The method of  claim 1  wherein said sealing composition further comprises a lightweight, filler selected from the group consisting of amorphous silica, fumed silica, diatomaceous earth, and fly ash.  
     
     
         20 . The method of  claim 19  wherein said lightweight filler is amorphous silica.  
     
     
         21 . The method of  claim 19  wherein said lightweight filler is present in said sealing composition in an amount in the range of from about 5% to about 50% by weight thereof.  
     
     
         22 . The method of  claim 1  wherein said sealing composition further comprises sand.  
     
     
         23 . The method of  claim 22  wherein said sand has a mesh size in the range of from about 70 mesh to about 140 mesh.  
     
     
         24 . The method of  claim 22  wherein said sand is present in said sealing composition in an amount in the range of from about 5% to about 30% by weight thereof.  
     
     
         25 . The method of  claim 1  wherein said sealing composition further comprises a delayed catalyst for causing said sealing composition to harden selected from the group consisting of encapsulated hydrochloric acid, encapsulated maleic acid, encapsulated salicylic acid and encapsulated sodium bisulfate.  
     
     
         26 . The method of  claim 25  wherein said delayed catalyst is encapsulated sodium bisulfate.  
     
     
         27 . The method of  claim 25  wherein said delayed catalyst is present in said sealing composition in an amount in the range of from about 0.1% to about 5% by weight thereof.  
     
     
         28 . A hardenable, low density sealing composition comprising: 
 a hardenable furan liquid resin mixture;    an organosilane coupling agent;    a cationic surfactant; and    hollow microspheres.    
     
     
         29 . The sealing composition of  claim 28  wherein said hardenable furan liquid resin mixture comprises a 2-furanmethanol homopolymer present in said mixture in an amount in the range of from about 55% to about 60% by weight thereof and furfuryl alcohol present in said mixture in an amount in the range of from about 40% to about 45% by weight thereof.  
     
     
         30 . The sealing composition of  claim 28  wherein said hardenable furan liquid resin mixture is present in an amount in the range of from about 10% to about 50% by weight thereof.  
     
     
         31 . The sealing composition of  claim 28  wherein said organosilane coupling agent is selected from the group consisting of N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-gylcidoxypropyltrimethoxysilane and n-beta(aminoethyl)-gamma-aminopropyltrimethoxysilane.  
     
     
         32 . The sealing composition of  claim 28  wherein said organosilane coupling agent is N-2-(aminoethyl)-3-aminopropyltrimethoxysilane.  
     
     
         33 . The sealing composition of  claim 28  wherein said organosilane coupling agent is present in an amount in the range of from about 0.1% to about 3% by weight thereof.  
     
     
         34 . The sealing composition of  claim 28  wherein said cationic surfactant is selected from the group consisting of ethoxylated nonyl phenol phosphate ester, C 12 -C 22  alkyl phosphonates and mixtures of one or more cationic surfactants and one or more non-ionic surfactants.  
     
     
         35 . The sealing composition of  claim 28  wherein said cationic surfactant is a C 12 -C 22  alkyl phosphonate.  
     
     
         36 . The sealing composition of  claim 28  wherein said cationic surfactant is present in an amount in the range of from about 0.1% to about 10% by weight thereof.  
     
     
         37 . The sealing composition of  claim 28  wherein said hollow microspheres are selected from the group consisting of hollow mineral glass spheres, hollow silica-alumina spheres, glass spheres and ceramic spheres.  
     
     
         38 . The sealing composition of  claim 28  wherein said hollow microspheres are mineral glass spheres.  
     
     
         39 . The sealing composition of  claim 28  wherein said hollow microspheres are present in an amount in the range of from about 5% to about 50% by weight thereof.  
     
     
         40 . The sealing composition of  claim 28  which further comprises a solvent or diluent selected from the group consisting of 2-butoxy ethanol, butyl acetate, furfuryl acetate and miktures thereof.  
     
     
         41 . The sealing composition of  claim 40  wherein said solvent or diluent is furfuryl acetate.  
     
     
         42 . The sealing composition of  claim 40  wherein said solvent or diluent is present in an amount in the range of from about 5% to about 60% by weight thereof.  
     
     
         43 . The sealing composition of  claim 28  which further comprises a dispersing agent selected from the group consisting of naphthalene-sulfonate-formaldehyde condensate, acetone-formaldehyde-sulfite condensate and glucano-delta-lactone.  
     
     
         44 . The sealing composition of  claim 43  wherein said dispersing agent is naphthalene-sulfonate-formaldehyde condensate.  
     
     
         45 . The sealing composition of  claim 43  wherein said dispersing agent is present in an amount in the range of from about 0.1% to about 10% by weight thereof.  
     
     
         46 . The sealing composition of  claim 28  which further comprises a lightweight filler selected from the group consisting of amorphous silica, fumed silica, diatomaceous earth, and fly ash.  
     
     
         47 . The sealing composition of  claim 46  wherein said lightweight filler is amorphous silica.  
     
     
         48 . The sealing composition of  claim 46  wherein said lightweight filler is present in an amount in the range of from about 5% to about 50% by weight thereof.  
     
     
         49 . The sealing composition of  claim 28  which further comprises sand.  
     
     
         50 . The sealing composition of  claim 49  wherein said sand has a mesh size in the range of from about 70 mesh to about 140 mesh.  
     
     
         51 . The sealing composition of  claim 49  wherein said sand is present in an amount in the range of from about 5% to about 30% by weight thereof.  
     
     
         52 . The sealing composition of  claim 28  which further comprises a delayed catalyst for causing said sealing composition to harden selected from the group consisting of encapsulated hydrochloric acid, encapsulated maleic acid, encapsulated salicylic acid and encapsulated sodium bisulfate.  
     
     
         53 . The sealing composition of  claim 52  wherein said delayed catalyst is encapsulated sodium bisulfate.  
     
     
         54 . The sealing composition of  claim 52  wherein said delayed catalyst is present in an amount in the range of from about 0.1% to about 5% by weight thereof.