Method of producing micronized barite particles

Abstract

A drilling fluid composition that contains micronized barite particles with a particle size in the range of 1 to 5 μm, and also a method of fracturing a subterranean formation using the drilling fluid composition. Various embodiments of the micronized barite particles and the method of making thereof, the drilling fluid composition, and the method of fracturing a subterranean formation are also provided.

1 - 14 . (canceled) 
     
     
         15 . A method of making micronized barite particles, comprising:
 stirring a suspension solution comprising a barite mixture and at least one chelating agent;   filtering the suspension solution to form a filter cake comprising barite; and   grinding the filter cake to form the micronized barite particles each having a particle size in the range of 1 to 5 μm,   wherein an amount of barite in the barite mixture is at least 80 wt %, and   wherein an amount of said chelating agent in the suspension solution is in the range of 1 wt % to 20 wt %, relative to the total weight of the suspension solution.   
     
     
         16 . The method of  claim 15 , further comprising:
 grinding the barite mixture prior to the stirring.   
     
     
         17 . The method of  claim 15 , wherein the suspension solution is centrifugally stirred with a rotational speed of at least 500 rpm, at a temperature in the range of 40 to 80° C. 
     
     
         18 . The method of  claim 15 , wherein the amount of barite in the barite mixture is at least 95 wt %, and wherein the amount of said chelating agent in the solution is in the range of 1 wt % to 10 wt %. 
     
     
         19 . The method of  claim 15 , wherein said chelating agent is at least one selected from the group consisting of ethylenediamine tetraacetic acid, glutamic diacetic acid, hydroxyethylenediamine triacetic acid, and salts thereof. 
     
     
         20 . The method of  claim 15 , wherein the suspension solution has a pH in the range of 7 to 14.