Hydraulic fracturing with slick water from dry blends
A “slick water” fluid for hydraulic fracturing of wells is provided that is mixed by adding solid polymer and solid additives to water. The fluid may be batch mixed or mixed in a continuous process using standard blending equipment. Components are selected that are environmentally preferred. Lower cost and environmental benefits are realized.
1 . A method for hydraulic fracturing a well, comprising:
supplying a powdered water-soluble polymer selected to form slick water;
forming a mixture of powdered water-soluble additives for fracturing fluid;
forming a mixture of the powdered water-soluble additives and the powdered polymer to form a dry blend of polymer and additives;
adding the dry blend to water to form a fracturing fluid and pumping the fluid down a well.
2 . The method of claim 1 wherein the dry blend contains at least 30 per cent by volume additives
3 . The method of claim 1 wherein the water-soluble additives comprise a mixture of powdered biocide and clay stabilizer.
4 . The method of claim 3 wherein the water-soluble additives further comprise a scale inhibitor, an oxygen scavenger or a surfactant.
5 . The method of claim 1 wherein the water-soluble polymer is a polyacrylamide.
6 . The method of claim 1 wherein adding the dry blend to water includes putting the dry blend in an eductor and flowing water past the eductor as a slip stream.
7 . The method of claim 1 wherein the additives are selected to be approximately the same density.
8 . The method of claim 1 wherein the additives are selected to be approximately the same particle size.
9 . A mixture of solids for use in a hydraulic fracturing fluid, comprising:
a powdered water-soluble polymer selected to form slick water; and
a mixture of powdered water-soluble additives for fracturing fluid.
10 . The mixture of claim 9 wherein the water-soluble additives consist of a biocide and a clay stabilizer.
11 . The mixture of claim 10 wherein the biocide is Dazomet and the clay stabilizer is choline chloride.
12 . The mixture of claim 9 wherein the powdered water-soluble polymer comprises a polyacrylamide.
13 . The mixture of claim 9 wherein the water-soluble additives in the mixture are approximately the same density.
14 . The mixture of claim 9 wherein the water-soluble additives in the mixture are approximately the same particle size.
15 . The mixture of claim 10 further comprising a powdered additive selected from the group consisting of a scale inhibitor, an oxygen scavenger and a surfactant.
16 . The mixture of claim 9 wherein, in the water-soluble additives, any oxygen scavenger has an LD 50 on rats greater than 2000, any scale inhibitor has an LD 50 greater than 5000 and any clay stabilizer has an LD 50 on rats greater than 100.