Methods and compositions of a storable relatively lightweight proppant slurry for hydraulic fracturing and gravel packing applications

Abstract

Methods and compositions useful for subterranean formation treatments, such as hydraulic fracturing treatments and sand control that utilize relatively lightweight and/or substantially neutrally buoyant particulates. Particles that may be employed include particulates of naturally occurring materials that may be optionally strengthened or hardened by exposure to a modifying agent; porous materials including selectively configured porous material particles manufactured and/or treated with selected glazing materials, coating materials and/or penetrating materials; and well treating aggregates composed of an organic lightweight material and a weight modifying agent. The relatively lightweight particulate may be suspended as a substantially neutral buoyant particulate and stored with a carrier fluid as a pumpable slurry.

1 . A storable aqueous pumpable suspension comprising: 
 (a.) a relatively lightweight proppant; and    (b.) a carrier fluid    wherein the relatively lightweight proppant is substantially neutrally buoyant.    
     
     
         2 . The storable aqueous pumpable suspension of  claim 1 , wherein the relatively lightweight proppant is an ultra lightweight proppant having an apparent specific gravity less than or equal to 2.45.  
     
     
         3 . The storable aqueous pumpable suspension of  claim 2 , wherein the ULW proppant has an apparent specific gravity less than 2.35.  
     
     
         4 . The storable aqueous pumpable suspension of  claim 3 , wherein the ULW proppant has an apparent specific gravity less than 2.25.  
     
     
         5 . The storable aqueous pumpable suspension of  claim 4 , wherein the ULW proppant has an apparent specific gravity less than 2.00.  
     
     
         6 . The storable aqueous pumpable suspension of  claim 5 , wherein the ULW proppant has an apparent specific gravity less than 1.75.  
     
     
         7 . The storable aqueous pumpable suspension of  claim 6 , wherein the ULW proppant has an apparent specific gravity less than 1.25.  
     
     
         8 . The storable aqueous pumpable suspension of  claim 1 , wherein the ULW proppant is a modified naturally occurring material resistant to deformation.  
     
     
         9 . The storable aqueous pumpable suspension of  claim 8 , wherein the ULW proppant is selected from the group consisting of ground or crushed nut shells, ground or crushed seed shells, ground or crushed fruit pits, processed wood, or a mixture thereof.  
     
     
         10 . The storable aqueous pumpable suspension of  claim 2 , wherein the ULW proppant is at least partially surrounded by at least one layer of a protective or hardening coating.  
     
     
         11 . The storable aqueous pumpable suspension of  claim 2 , wherein the apparent specific gravity of the ULW proppant is preferably the same but no greater than 0.25 higher than the apparent specific gravity of the carrier fluid.  
     
     
         12 . The storable aqueous pumpable suspension of  claim 10 , wherein the ULW proppant is a porous particulate treated with a non-porous penetrating, coating and/or glazing material.  
     
     
         13 . The storable aqueous pumpable suspension of  claim 12 , wherein either: 
 (i.) the apparent specific gravity of the ULW proppant is less than the apparent specific gravity of the porous particulate;    (ii.) the permeability of the ULW proppant is less than the permeability of the porous particulate; or    (iii.) the porosity of the ULW proppant is less than the porosity of the porous particulate.    
     
     
         14 . The storable aqueous pumpable suspension of  claim 12 , wherein the porous particulate comprises a multitude of coated particulates bound together.  
     
     
         15 . The storable aqueous pumpable suspension of  claim 12 , wherein the strength of the ULW proppant is greater than the strength of the porous particulate.  
     
     
         16 . The storable aqueous pumpable suspension of  claim 12 , wherein the porous particulate is a ceramic or organic polymeric material.  
     
     
         17 . The storable aqueous pumpable suspension of  claim 12 , wherein the porous particulate has an internal porosity from about 10 to about 75 volume percent.  
     
     
         18 . The storable aqueous pumpable suspension of  claim 12 , wherein the thickness of the coating of the ULW proppant is from about 1 to about 5 microns.  
     
     
         19 . The storable aqueous pumpable suspension of  claim 12 , wherein the extent of penetration of the penetrating material is from less than about 1% penetration by volume to less than about 25% penetration by volume.  
     
     
         20 . The storable aqueous pumpable suspension of  claim 2 , wherein the ULW proppant is an aggregate of an organic lightweight material and a weight modifying agent wherein the apparent specific gravity of the organic lightweight material is either greater or less than the apparent specific gravity of the aggregate.  
     
     
         21 . The storable aqueous pumpable suspension of  claim 20 , wherein the organic lightweight material is polymeric.  
     
     
         22 . The storable aqueous pumpable suspension of  claim 20 , wherein at least 52% by volume of the aggregate is the weight modifying agent.  
     
     
         23 . The storable aqueous pumpable suspension of  claim 20 , wherein the amount of organic lightweight material in the aggregate is between from about 10 to about 90 percent by volume.  
     
     
         24 . The storable aqueous pumpable suspension of  claim 20 , wherein the weight modifying agent is a weighting agent.  
     
     
         25 . The storable aqueous pumpable suspension of  claim 24 , wherein the apparent specific gravity of the aggregate is at least one and a half times the apparent specific gravity of the organic lightweight material.  
     
     
         26 . The storable aqueous pumpable suspension of  claim 20 , wherein the apparent specific gravity of the aggregate is at least 1.0.  
     
     
         27 . The storable aqueous pumpable suspension of  claim 25 , wherein the apparent specific gravity of the organic lightweight material is less than or equal to 1.1.  
     
     
         28 . The storable aqueous pumpable suspension of  claim 2 , wherein the ULW proppant is an aggregate comprising, as the continuous phase, an organic lightweight material having an apparent specific gravity less than about 1.1 and, as the discontinuous phase, a weighting agent, wherein the apparent specific gravity of the aggregate is at least 1.25.  
     
     
         29 . The storable aqueous pumpable suspension of  claim 1 , wherein the carrier fluid is gelled.  
     
     
         30 . The storable aqueous pumpable suspension of  claim 1 , wherein the carrier fluid contains a suspending/thixotropic agent.  
     
     
         31 . The storable aqueous pumpable suspension of  claim 30 , wherein the suspending/thixotropic agent is selected from the group consisting of carrageenan, scleroglucan, succinoglycan, welan gum, xanthan gum, cellulose, guar, starch, polyalkylene oxides, and derivatives thereof.  
     
     
         32 . The storable aqueous pumpable suspension of  claim 1 , wherein the carrier fluid further comprises at least one member selected from the group consisting of a gelling agent, crosslinking agent, gel breaker, surfactant, biocide, surface tension reducing agent, foaming agent, defoaming agent, demulsifier, non-emulsifier, scale inhibitor, gas hydrate inhibitor, polymer specific enzyme breaker, oxidative breaker, buffer, clay stabilizer, acid or a mixture thereof.  
     
     
         33 . The storable aqueous pumpable suspension of  claim 1 , wherein the suspension, when diluted with water, is at a concentration suitable for fracturing a subterranean formation.  
     
     
         34 . A storable aqueous pumpable suspension comprising at least one ultra lightweight (ULW) proppant suspended in either 
 (i.) a weighted carrier fluid, wherein the apparent specific gravity of the ULW proppant is preferably the same as, but no greater than 0.25 higher than, the apparent specific gravity of the carrier fluid; or    (ii.) a weakly gelled carrier fluid optionally containing a friction reducing agent, wherein the amount of friction reducing agent is between from about 0 to about 10 pounds per thousand gallons of carrier fluid and/or the weakly gelled carrier fluid has a viscosity of from about 1 to about 20 cps; or    (iii.) a combination of (i.) and (ii.).    
     
     
         35 . The storable aqueous pumpable suspension of  claim 34 , wherein the viscosity of the weakly gelled carrier fluid is from about 1 to about 10 cps.  
     
     
         36 . The storable aqueous pumpable suspension of  claim 34 , wherein the ULW proppant is suspended in a weighted carrier fluid, the apparent specific gravity of the ULW proppant being no greater than 0.20 higher than the apparent specific gravity of the carrier fluid.  
     
     
         37 . The storable aqueous pumpable suspension of  claim 34 , wherein the carrier fluid further contains welan gum, xanthan gum, cellulose, guar, starch or a derivative thereof.  
     
     
         38 . The storable aqueous pumpable suspension of  claim 34 , wherein the ULW proppant has a apparent specific gravity less than or equal to 2.45.  
     
     
         39 . The storable aqueous pumpable suspension of  claim 38 , wherein the ULW proppant has an apparent specific gravity less than 2.35.  
     
     
         40 . The storable aqueous pumpable suspension of  claim 39 , wherein the ULW proppant has an apparent specific gravity less than 2.25.  
     
     
         41 . The storable aqueous pumpable suspension of  claim 40 , wherein the ULW proppant has an apparent specific gravity less than 2.00.  
     
     
         42 . The storable aqueous pumpable suspension of  claim 41 , wherein the ULW proppant has an apparent specific gravity less than 1.75.  
     
     
         43 . The storable aqueous pumpable suspension of  claim 42 , wherein the ULW proppant has an apparent specific gravity less than 1.25.  
     
     
         44 . The storable aqueous pumpable suspension of  claim 34 , wherein the ULW proppant is a modified naturally occurring material resistant to deformation.  
     
     
         45 . The storable aqueous pumpable suspension of  claim 44 , wherein the modified naturally occurring material is selected from the group consisting of ground or crushed nut shells, ground or crushed seed shells, ground or crushed fruit pits, processed wood, or a mixture thereof.  
     
     
         46 . The storable aqueous pumpable suspension of  claim 34 , wherein the ULW proppant is a porous particulate treated with a non-porous penetrating, coating and/or glazing material.  
     
     
         47 . The storable aqueous pumpable suspension of  claim 46 , wherein either: 
 (i.) the apparent specific gravity of the ULW proppant is less than the apparent specific gravity of the porous particulate;    (ii.) the permeability of the ULW proppant is less than the permeability of the porous particulate; or    (iii.) the porosity of the ULW proppant is less than the porosity of the porous particulate.    
     
     
         48 . The storable aqueous pumpable suspension of  claim 46 , wherein the strength of the ULW proppant is greater than the strength of the porous particulate.  
     
     
         49 . The storable aqueous pumpable suspension of  claim 46 , wherein the porous particulate is a ceramic or organic polymeric material.  
     
     
         50 . The storable aqueous pumpable suspension of  claim 46 , wherein the porous particulate has an internal porosity from about 10 to about 75 volume percent.  
     
     
         51 . The storable aqueous pumpable suspension of  claim 34 , wherein the ULW proppant is an aggregate of an organic lightweight material and a weight modifying agent wherein the apparent specific gravity of the organic lightweight material is either greater or less than the apparent specific gravity of the aggregate.  
     
     
         52 . The storable aqueous pumpable suspension of  claim 51 , wherein the weight modifying agent is a weighting agent.  
     
     
         53 . The storable aqueous pumpable suspension of  claim 51 , wherein the apparent specific gravity of the aggregate is at least one and a half times the apparent specific gravity of the organic lightweight material.  
     
     
         54 . The storable aqueous pumpable suspension of  claim 51 , wherein the apparent specific gravity of the aggregate is at least 1.0.  
     
     
         55 . The storable aqueous pumpable suspension of  claim 34 , wherein wherein the carrier fluid further comprises at least one member selected from the group consisting of a gelling agent, crosslinking agent, gel breaker, surfactant, biocide, surface tension reducing agent, foaming agent, defoaming agent, demulsifier, non-emulsifier, scale inhibitor, gas hydrate inhibitor, polymer specific enzyme breaker, oxidative breaker, buffer, clay stabilizer, acid or a mixture thereof.