Proppant for hydraulic fracturing of oil and gas wells
The present invention relates to a proppant for the hydraulic fracturing of oil or gas wells, which consists of a mixture of from 10 to 95% by weight of a spherical proppant and from 5 to 90% by weight of an angular material, the percentages being based on the total weight of the mixture. The proppant obtained according to the present invention is useful for eliminating or decreasing the “flow-back” phenomenon in operations in oil or gas wells.
1. A proppant for the hydraulic fracturing of oil or gas wells, characterized in that it consists of a mixture of 90% by weight of the spherical proppant and 10% by weight of the angular material, the percentages being based on the total weight of the mixture.
2. A proppant for the hydraulic fracturing of oil or gas wells, characterized in that it consists of a mixture of from 10 to 95% by weight of a spherical proppant and from 5 to 90% by weight of an angular material, the percentages being based on the total weight of the mixtures, and wherein the spherical proppant component consists of a ceramic proppant having the following chemical composition:
Oxide
Contents (%)
Al 2 O 3
72.8
Fe 2 O 3
12.5
SiO 2
13.0
TiO 2
1.47
CaO + MgO
0.09
K 2 O + Na 2 O
0.04
Mineralogical composition
Corundum
Mulite
hermatite
Solubility in HCl + HF, %
<6.
3. A proppant for the hydraulic fracturing of oil or gas wells, characterized in that it consists of a mixture of from 10 to 95% by weight of a spherical ceramic proppant and from 5 to 90% by weight of an angular ceramic material, the percentages being based on the total weight of the mixtures, and wherein the proppant is characterized by the absence of resin materials.
4. A proppant according to claim 3 , characterized in that it consists of a mixture of 80% by weight of the spherical proppant and 20% by weight of the angular material, the percentages being based on the total weight of the mixture.
5. A proppant according to claim 3 , characterized in that it consists of a mixture of 70% by weight of the spherical proppant and 30% by weight of the angular material, the percentages being based on the total weight of the mixture.
6. A proppant according to claim 3 , characterized in that the angular material component consists of a ceramic material having the following chemical composition:
Oxide
Contents (%)
Al 2 O 3
79.3
Fe 2 O 3
14.5
SiO 2
3.65
TiO 2
1.87
CaO + MgO
1.06
K 2 O + Na 2 O
0.83
Free silica
No contents
Mineralogical composition
Corundum
Mulite
hermatite.
7. A proppant according to claim 3 , characterized in that it consists of a mixture of 90% by weight of the spherical proppant and 10% by weight of the angular material, the percentages being based on the total weight of the mixture.
8. A proppant according to claim 3 , wherein the spherical and angular material is bauxite.
9. A method of eliminating or decreasing the flow back effect in operations of oil or gas wells, comprising the step of injecting the proppant as defined in claim 3 into a well.