Downhole heating methods for solution mining

Abstract

A method for mining soluble minerals from a subterranean deposit that comprises injecting a mining solvent into an injection wellbore passing through or contacting the deposit, wherein a heating means is allowed to heat the mining solvent while downhole and inside the wellbore thereby increasing the solvent temperature and reducing solvent heat loss is provided. The heated solvent is allowed to dissolve some of the soluble minerals from the deposit forming a mineral solution which is produced to surface.

1 . A method for mining soluble minerals from a subterranean deposit containing the soluble minerals, the method comprising the steps of:
 a. providing an injection wellbore contacting the subterranean deposit;   b. providing heating means in the injection wellbore;   c. injecting a mining solvent into the injection wellbore;   d. allowing the heating means to heat the mining solvent while inside the injection wellbore to form a heated mining solvent;   e. allowing the heated mining solvent to enter into the subterranean deposit and dissolve a portion of the soluble minerals from the subterranean deposit, thereby forming a mineral solution comprising the heated mining solvent and the portion of the soluble minerals; and   f. producing the mineral solution to surface.   
     
     
         2 . The method of  claim 1  further comprising, before producing the mineral solution to the surface, the step of allowing the heating means to heat the mineral solution. 
     
     
         3 . The method of  claim 1  wherein the step of producing the mineral solution to surface comprises use of a production wellbore. 
     
     
         4 . The method of  claim 3  further comprising the step of providing a second heating means in the production wellbore to heat the mineral solution. 
     
     
         5 . The method of  claim 1  wherein the injection wellbore comprises at least one of: a vertical section; and a horizontal section. 
     
     
         6 . The method of  claim 5  wherein the step of allowing the heating means to heat the mining solvent occurs while inside the at least one of: a vertical section; and a horizontal section. 
     
     
         7 . The method of  claim 1  wherein the soluble minerals comprise potassium chloride. 
     
     
         8 . The method of  claim 1  wherein the subterranean deposit comprises potash. 
     
     
         9 . A method for producing liquid fluid from a subterranean deposit containing soluble minerals, the method comprising the steps of:
 a. providing a production wellbore contacting the deposit;   b. providing heating means in the production wellbore;   c. allowing the liquid fluid to flow into the production wellbore;   d. allowing the heating means to heat the liquid fluid while inside the production wellbore to form a heated fluid; and   e. producing the heated fluid to surface.   
     
     
         10 . The method of  claim 9  wherein the liquid fluid is a mining solution comprising mined soluble minerals from the subterranean deposit. 
     
     
         11 . The method of  claim 9  wherein the production wellbore comprises: at least one of: a vertical section; and a horizontal section. 
     
     
         12 . The method of  claim 11  wherein the step of allowing the heating means to heat the liquid fluid occurs while inside the at least one of: a vertical section; and a horizontal section. 
     
     
         13 . The method of  claim 9  wherein the soluble minerals comprise potassium chloride. 
     
     
         14 . The method of  claim 9  wherein the subterranean deposit comprises potash. 
     
     
         15 . A method for mining soluble minerals from a subterranean deposit, the method comprising the steps of:
 a. providing an injection wellbore contacting the subterranean deposit;   b. providing a production wellbore contacting the subterranean deposit;   c. providing first heating means in the injection wellbore;   d. providing second heating means in the production wellbore;   e. injecting a mining solvent into the injection wellbore;   f. allowing the first heating means to heat the mining solvent while inside the injection wellbore to form a heated mining solvent;   g. allowing the heated mining solvent to enter into the subterranean deposit and dissolve a portion of the soluble minerals in the subterranean deposit, thereby forming a mineral solution comprising the heated mining solvent and the portion of the soluble minerals;   h. allowing the mineral solution to flow into the production wellbore;   i. allowing the second heating means to heat the mineral solution while inside the production wellbore to form a heated mineral solution; and   j. producing the heated mineral solution to surface.   
     
     
         16 . The method of  claim 15  wherein the injection wellbore comprises: at least one of: a vertical section; and a horizontal section. 
     
     
         17 . The method of  claim 16  wherein the step of allowing the first heating means to heat the mining solvent occurs while inside at least one of: a vertical section; and a horizontal section of the injection wellbore. 
     
     
         18 . The method of  claim 15  wherein the production wellbore comprises at least one of: a vertical section; and a horizontal section. 
     
     
         19 . The method of  claim 18  wherein the step of allowing the second heating means to heat the mineral solution occurs while inside the vertical section and/or the horizontal section of the production wellbore. 
     
     
         20 . The method of  claim 9  wherein the soluble minerals comprise potassium chloride. 
     
     
         21 . The method of  claim 9  wherein the subterranean deposit comprises potash. 
     
     
         22 . A method for producing liquid fluid from a subterranean region containing the liquid fluid, the method comprising the steps of:
 a. providing a production wellbore contacting the subterranean region;   b. providing heating means in the production wellbore;   c. allowing the liquid fluid to flow into the production wellbore;   d. allowing the heating means to heat the liquid fluid while inside the production wellbore to form a heated fluid; and   e. producing the heated fluid to surface.   
     
     
         23 . The method of  claim 22  wherein the fluid is a mining solvent comprising water. 
     
     
         24 . The method of  claim 22  wherein the production wellbore comprises: at least one of: a vertical section; and a horizontal section. 
     
     
         25 . The method of  claim 24  wherein the step of allowing the heating means to heat the liquid fluid occurs while inside at least one of: a vertical section; and a horizontal section. 
     
     
         26 . The method of  claim 22  wherein the soluble minerals comprise potassium chloride. 
     
     
         27 . The method of  claim 22  wherein the subterranean deposit comprises potash.