Method of manufacture and using rod-shaped proppants and anti-flowback additives
A sintered rod-shaped proppant and anti-flowback agent possesses high strength and high conductivity. The sintered rods comprise between about 0.2% by weight and about 4% by weight aluminum titanate. In some embodiments, the sintered rods are made by mixing bauxitic and non-bauxitic sources of alumina that may also contain several so-called impurities (such as TiO 2 ), extruding the mixture, and sintering it. The starting material may optionally be milled to achieve better compacity and crush resistance in the final sintered rod. A fracturing fluid may comprise the sintered rods alone or in combination with a proppant, preferably a proppant of a different shape.
1. A method of making a proppant or anti-flowback additive comprising:
a) providing a composition comprising at least about 90% by weight alumina and between about 0.15% and about 3.5% by weight TiO 2 ;
b) milling the composition;
c) forming at least one rod from the milled composition;
d) sintering the at least one rod; and
e) forming a proppant or anti-flowback additive comprising the sintered rod,
wherein the sintered rod has an average length to width ratio ranging from about 2:1 to about 4:1.
2. The method of claim 1 , wherein the sintered rod has an average diameter ranging from about 0.5 mm to about 1.5 mm.
3. The method of claim 1 , wherein the sintered rod has an average rod length ranging from about 2 mm to about 4 mm, and a narrow rod length distribution such that at least about 60% of the sintered rods has a length within 1 mm of the average rod length.
4. The method of claim 1 , wherein the composition further comprises bauxite.
5. The method of claim 1 , wherein the composition further comprises kaolin.
6. The method of claim 1 , wherein the composition further comprises bauxitic kaolin.
7. The method of claim 1 , wherein the proppant or anti-flowback additive has a packed void volume of greater than 40%.
8. The method of claim 1 , wherein the proppant or anti-flowback additive has an API crush resistance value ranging from about 5% by weight and about 9% crushed at 10,000 psi.
9. The method of claim 1 , wherein the proppant or anti-flowback additive has an API crush resistance value ranging from about 9% by weight and about 19% crushed at 15,000 psi.
10. The method of claim 1 , wherein the composition comprises between about 0.3% by weight and about 2.7% by weight TiO 2 .
11. The method of claim 1 , wherein the composition comprises between about 0.4% by weight and about 2.3% by weight TiO 2 .
12. The method of claim 1 wherein the sintered rods comprise between about 0.2% by weight and about 4% by weight aluminum titanate.
13. The method of claim 12 wherein the sintered rods comprise between about 0.5% by weight and about 3% by weight aluminum titanate.
14. The method of claim 13 wherein the sintered rods comprise between about 1% by weight and about 2.5% by weight aluminum titanate.
15. The method of claim 1 , wherein the sintered rods further has an silica content of less than about 4% by weight.
16. The method of claim 1 , wherein the sintered rod has a specific gravity ranging from 3.0 to 3.98.