Folded or crumpled proppants with increased material strength for hydraulic fracturing, gravel packing and frac packing
Relatively low strength and/or relatively low density, but ductile materials may be folded or crumpled and finely divided to give proppants for introduction into hydraulic fractures, where the folded or crumpled structure of the proppants gives relatively increased strength relative to the relatively low strength and/or relatively low density of the materials. Materials not previously considered suitable for proppants may be considered when structure or configured in this manner. Similarly to the case where crumpled paper within a cardboard box keeps it from collapsing, the folded or crumpled material spontaneously develops structural rigidity at relatively low volume fractions without a specific externally imposed design. The folded or crumpled proppants may also be used alone or together with conventional proppants for sand control in gravel packs or frac packs.
1. A proppant comprising:
at least one crumpled layer having outer perimeter defining a proppant volume, the at least one crumpled layer comprising a material selected from the group consisting of ceramic, metal, polymer, and combinations thereof; and
at least one interstice within the proppant volume adjacent the layer;
the proppant having:
an average particle size of from about 125 to about 1700 microns, and
a strength of from about 1,000 to about 10,000 psi (about 6.9 to about 69 MPa).
2. The proppant of claim 1 where:
the ceramic is selected from the group consisting of aluminosilicate, zirconia, metal carbides;
the metal is selected from the group consisting of aluminum, titanium;
the polymer is selected from the group consisting of carboxymethyl cellulose (CMC), polyethylene terephthalate, polyimides, polyethylene, polypropylene, polycarbonate, polyurethane; and
combinations thereof.
3. The proppant of claim 1 where the layer has a thickness ranging from about 1 mm to about 5 microns.
4. The proppant of claim 1 , where the proppant has a density less than about 2.45 g/cc.
5. A proppant comprising:
at least one crumpled layer having outer perimeter defining a proppant volume, the at least one crumpled layer comprising a material selected from the group consisting of ceramic, metal, polymer, and combinations thereof, where:
the ceramic is selected from the group consisting of aluminosilicate, zirconia, metal carbides; the metal is
titanium;
the polymer is selected from the group consisting of carboxymethyl cellulose (CMC), polyethylene terephthalate, polyimides, polyethylene, polypropylene, polycarbonate, polyurethane; and
combinations thereof; and
at least one interstice within the proppant volume adjacent the layer.
6. The proppant of claim 5 where the layer has a thickness ranging from about 1 mm to about 5 microns.
7. The proppant of claim 5 having an average particle size of from about 125 to about 1700 microns.
8. The proppant of claim 5 having a strength of from about 1,000 to about 10,000 psi (about 6.9 to about 69 MPa).
9. The proppant of claim 5 , where the proppant has a density less than about 2.45 g/cc.