Methods for Pillar Placement in Fracturing

Abstract

Methods for placing proppant aggregates using a diverting fluid comprising a diverting agent and a packing fluid. Proppant aggregates are introduced into a fracture that is fluidically connected to a wellbore through a plurality of perforations. Thereafter, a diverting diverting fluid is introduced into the wellbore to seal some perforations and leave at least one unsealed perforation. Once some perforations are sealed, a packing fluid is introduced into the fracture through the at least one unsealed perforation, thereby forming the proppant aggregates to move together and form a proppant bed within the fracture.

The invention claimed is: 
     
         1 . A method comprising:
 providing proppant aggregates; a diverting fluid comprising a diverting agent; and a packing fluid;   introducing the proppant aggregates into a fracture that is fluidically connected to a wellbore through a plurality of perforations;   introducing the diverting fluid into the wellbore thereby forming at least one sealed perforation and leaving at least one unsealed perforation; and   introducing the packing fluid into the fracture through the at least one unsealed perforation thereby allowing the proppant aggregates to form a proppant bed within the fracture.   
     
     
         2 . The method of  claim 1 , wherein the diverting agent is degradable. 
     
     
         3 . The method of  claim 2 , further comprising: allowing the degradable diverting agent to degrade thereby unsealing the at least one perforation. 
     
     
         4 . The method of  claim 1 , wherein the diverting agent is selected from the group consisting of: a polysaccharide, a chitin, a chitosan, a protein, an orthoester, an aliphatic polyester, a poly(glycolide), a poly(lactide), a poly(ε-caprolactone), a poly(hydroxybutyrate), a polyanhyride, an aliphatic polycarbonate, a poly(orthoester), a poly(amino acid), a poly(ethylene oxide), a polyphosphazene, any derivative thereof, and any combination thereof. 
     
     
         5 . The method of  claim 1 , wherein the diverting agent seals at least 60% of the perforations that fluidically connect the wellbore and the fracture. 
     
     
         6 . The method of  claim 1 , wherein the diverting agent seals at least 75% of the perforations that fluidically connect the wellbore and the fracture. 
     
     
         7 . The method of  claim 1 , wherein the at least one unsealed perforation is located at or near a bottom of the fracture. 
     
     
         8 . The method of  claim 1 , wherein the proppant aggregate comprises a binding fluid and a filler material selected from the group consisting of: sand, bauxite, ceramic material, glass material, polymer material, polytetrafluoroethylene material, nut shell piece, cured resinous particulate comprising a nut shell piece, seed shell piece, cured resinous particulate comprising seed shell piece, fruit pit piece, cured resinous particulate comprising fruit pit piece, wood, composite particulate, and any combination thereof. 
     
     
         9 . The method of  claim 8 , wherein the filler material is coated with an adhesive selected from the group consisting of: a non-aqueous tackifying agent, an aqueous tackifying agent, a silyl-modified polyamide, a zeta-potential modifying agent, a curable resin composition, and any combination thereof. 
     
     
         10 . The method of  claim 8 , wherein the binding fluid comprises a curable resin composition and an aqueous gel. 
     
     
         11 . The method of  claim 1 , wherein the packing fluid comprises proppants. 
     
     
         12 . A method comprising:
 providing proppant aggregates; a diverting fluid comprising a degradable diverting agent; and a packing fluid;   introducing the proppant aggregates into a fracture that is fluidically connected to a wellbore through a plurality of perforations;   introducing the diverting fluid into the wellbore thereby forming at least one sealed perforation and leaving at least one unsealed perforation;   introducing the packing fluid into the fracture through the at least one unsealed perforation thereby allowing the proppant aggregates to form a proppant bed within the fracture; and   allowing the degradable diverting agent to degrade thereby unsealing the at least one perforation.   
     
     
         13 . The method of  claim 12 , wherein the diverting agent is selected from the group consisting of: a polysaccharide, a chitin, a chitosan, a protein, an orthoester, an aliphatic polyester, a poly(glycolide), a poly(lactide), a poly(ε-caprolactone), a poly(hydroxybutyrate), a polyanhyride, an aliphatic polycarbonate, a poly(orthoester), a poly(amino acid), a poly(ethylene oxide), a polyphosphazene, any derivative thereof, and any combination thereof. 
     
     
         14 . The method of  claim 12 , wherein the diverting agent seals at least 60% of the plurality of perforations that fluidically connect the wellbore and the fracture. 
     
     
         15 . The method of  claim 12 , wherein the diverting agent seals at least 75% of the plurality of perforations that fluidically connect the wellbore and the fracture. 
     
     
         16 . The method of  claim 12 , wherein the at least one unsealed perforation is located at or near a bottom of the fracture. 
     
     
         17 . The method of  claim 12 , wherein the proppant aggregate comprises a binding fluid and a filler material selected from the group consisting of: sand, bauxite, ceramic material, glass material, polymer material, polytetrafluoroethylene material, nut shell piece, cured resinous particulate comprising a nut shell piece, seed shell piece, cured resinous particulate comprising seed shell piece, fruit pit piece, cured resinous particulate comprising fruit pit piece, wood, composite particulate, and any combination thereof. 
     
     
         18 . The method of  claim 17 , wherein the filler material is coated with an adhesive selected from the group consisting of: a non-aqueous tackifying agent, an aqueous tackifying agent, a silyl-modified polyamide, a zeta-potential modifying agent, a curable resin composition, and any combination thereof. 
     
     
         19 . The method of  claim 17 , wherein the binding fluid comprises a curable resin composition and an aqueous gel. 
     
     
         20 . The method of  claim 12 , wherein the packing fluid comprises proppants.