Drilling composition, process for its preparation, and applications thereof

Abstract

The present invention relates to a drilling composition comprising an organic phase having at least one linear or branched, cyclic or non-cyclic, saturated hydrocarbon, at least one ester, water or aqueous phase, and at least one additive. The present invention additionally relates to the use and preparation of the drilling composition, to a drilling system, to a process for making a borehole, to a process for conveying cuttings, to a process for treating a drill head, and to a process for production of oil and/or gas.

1 . A drilling composition comprising
 I) an organic phase comprising components
 i. from about 20 wt. % to about 99.999 wt. %, based on the total weight of components i. and ii., of at least one linear or branched, cyclic or non-cyclic, saturated hydrocarbon, 
 ii. from about 0.001 wt. % to about 25 wt. %, based on the total weight of components i. and ii., of at least one ester, 
   II) from 0 to about 50 wt. %, based on the total weight of the composition, of water or aqueous phase, and   III) from 0 to about 60 wt. %, based on the total weight of the composition, of at least one additive,   
       wherein the sum of the weight components I) to III) is 100 wt. %. 
     
     
         2 . The drilling composition according to  claim 1 , wherein the at least one hydrocarbon is at least one alkane. 
     
     
         3 . The drilling composition according to  claim 1 , wherein the at least one ester is at least one ester selected from the group consisting of esters formed from at least one C 1  to C 24  monocarboxylic acid with at least one mono-functional alcohol. 
     
     
         4 . The drilling composition according to  claim 1 , wherein the composition is in the form of an emulsion. 
     
     
         5 . The drilling composition according to  claim 1 , wherein the at least one additive is at least one additive selected from the group consisting of weighting agents, clays, fluid loss additives, pH modifiers, viscosity modifiers, filtration control agents, emulsifiers, salts, wetting agents, dispersants. 
     
     
         6 . The drilling composition according to  claim 1 , wherein the at least one ester has a carbon chain distribution of the acid-derived component determined according to ISO 5508 with carbon numbers in the ranges of from 0 to 2.00% C 6 , from 3.00% to 10.00% C 8 , from 3.00% to 10.00% C 10 , from 50.00% to 94.00% C 12 , from 0 to 25.00% C 14 , from 0 to 5.00% C 16  and from 0 to 1.00% C 18 . 
     
     
         7 . The drilling composition according to  claim 1 , wherein the at least one ester has a carbon chain distribution of the acid-derived component determined according to ISO 5508 with carbon numbers in the ranges of from 0 to 2.00% C 6 , from 0 to 10.00% C 8 , from 0 to 10.00% C 10 , from 50.00% to 95.00% C 12 , from 5.00% to 35.00% C 14 , from 0 to 5.00% C 16  and from 0 to 1.00% C 18 . 
     
     
         8 . A process for the preparation of a drilling composition, comprising the steps:
 a) providing as component i. from about 20 wt. % to about 99.999 wt. %, based on the total amount of i. and ii., of at least one linear or branched, cyclic or non-cyclic, saturated hydrocarbon,   b) providing as component ii. from about 0.001 wt. % to about 25 wt. %, based on the total amount of i. and ii., of at least one ester, and   
       wherein the sum of the weight amounts provided in a) and b) is 100 wt. %,
 c) combining the at least one hydrocarbon and the at least one ester. 
 
     
     
         9 . A process for preparation of a drilling composition, comprising the steps:
 A) preparation of an organic phase comprising components
 i. from about 20 wt. % to about 99.999 wt. %, based on the total weight of components i. and ii., of at least one linear or branched, cyclic or non-cyclic, saturated hydrocarbon, 
 ii. from about 0.001 wt. % to about 25 wt. %, based on the total weight of components i. and ii., of at least one ester, 
   B) preparation of an aqueous phase comprising from about 50 wt. % to 100 wt. % water, based on the total amount of aqueous phase,   C) combination of the organic phase prepared in step A) with from 0 to 50 wt. %, based on the total weight of the composition, of the aqueous phase prepared in step B), and   D) combination of at least one of the organic phase, the aqueous phase and the combination of the organic phase and the aqueous phase with from 0 to about 60 wt. %, based on the total weight of the composition, of at least one additive.   
     
     
         10 . The process according to  claim 9 , further comprising the step
 E) homogenization.   
     
     
         11 . A process according to  claim 9 , wherein the composition at the end of at least one of steps C), D) or E) is in the form of an emulsion. 
     
     
         12 . The process according to  claim 11 , wherein the emulsion is a nanoemulsion or a microemulsion with droplet sizes in the range from 5 nm to 1000 μm. 
     
     
         13 . The process according to  claim 8 , wherein the at least one ester is at least one ester selected from the group consisting of esters formed from at least one C 1  to C 24  monocarboxylic acid with at least one monofunctional alcohol. 
     
     
         14 . The process according to  claim 8 , wherein the at least one ester has a carbon chain distribution of the acid-derived component determined according to ISO 5508 with carbon numbers in the ranges of from 0 to 2.00% C 6 , from 3.00% to 10.00% C 8 , from 3.00% to 10.00% C 10 , from 50.00% to 94.00% C 12 , from 0 to 25.00% C 14 , from 0 to 5.00% C 16  and from 0 to 1.00% C 18 . 
     
     
         15 . The process according to  claim 8 , wherein the at least one ester has a carbon chain distribution of the acid-derived component determined according to ISO 5508 with carbon numbers in the ranges of from 0 to 2.00% C 6 , from 0 to 10.00% C 8 , from 0 to 10.00% C 10 , from 50.00% to 95.00% C 12 , from 5.00% to 35.00% C 14 , from 0 to 5.00% C 16  and from 0 to 1.00% C 18 . 
     
     
         16 . A drilling composition obtainable by a process according to  claim 8  and having at least one of the properties:
 γ1) a plastic viscosity measured at 50° C. according to the herein described test method in the range from 15 to 75 mPa·s;   γ2) a yield point measured at 50° C. according to the herein described test method in the range from 5 to 45 lb/100 ft 2  (2.4 to 21.6 Pa); or   γ3) a gel strength measured at 50° C. according to the herein described test method in the range from 4 to 25 lb/100 ft 2  (1.9 to 12 Pa).   
     
     
         17 . (canceled) 
     
     
         18 . A drilling system comprising a drill head, a drill string, a reservoir for drilling composition and a drilling composition according to  claim 1 . 
     
     
         19 . A process for making a borehole comprising the steps:
 a1) providing a composition according to  claim 1 ;   a2) drilling a hole in a subterranean formation; and   a3) circulating the composition provided in a1) at least partially in the hole at least partially while drilling.   
     
     
         20 . A process for conveying cuttings from a hole drilled in a subterranean formation, comprising the steps:
 b1) providing a composition according to  claim 1 , and   b2) circulating the composition provided in b1) at least partially in the hole.   
     
     
         21 . The process according to  claim 20 , wherein the composition is circulated at least partially while drilling the hole. 
     
     
         22 . A process for treatment of a drill head comprising the steps:
 c1) providing a composition according to  claim 1 , and   c2) circulating the composition provided in c1) at least partially through the drill head at least partially while the drill head is operated in a subterranean formation.   
     
     
         23 . The process according to  claim 22 , wherein the treatment is at least one of cleaning, cooling or lubrication. 
     
     
         24 . A process for production of at least one of oil or gas, comprising the steps:
 d1) providing a composition according to  claim 1 ,   d2) drilling at least one hole in a subterranean formation while at least partially circulating the composition provided in d1) at least partially in the hole;   d3) obtaining at least one of oil and gas from the subterranean formation at least partially by means of the at least one hole drilled in d2); and   d4) optionally, subjecting the at least one of oil and gas to at least one processing step selected from purifying, refining or treating.