The present embodiments are directed, in part, to coated particulates, methods of preparing thereof, and methods of using the same, for example, as turf infill.
Polymer-coated proppants for hydraulic fracturing of oil and gas wells have an outer layer portion that comprises an organofunctional coupling agent, preferably an organofunctional silane coupling agent. The use of an organofunctional silane coupling agent in the outer layer portion of the proppant coating is preferably chosen to expose functionalities that will be reactive towards similar functionalities of adjacent and similarly coated proppants so that, when introduced downhole, these proppants form interparticle bonds at the temperatures and crack closure pressures found downhole in fractured strata. Such enhanced interparticle bonding helps keep the proppant in the fracture and maintains conductivity with reduced flowback. The invention also helps proppants designed for low temperature well to bond more firmly and allows proppants designed for high temperature wells to bond well even at lower downhole temperatures, thereby extending their useful range.
Polymer coated proppants for hydraulic fracturing of oil and gas wells have an outer layer portion that comprises an organofunctional coupling agent, preferably an organofunctional silane coupling agent. The use of an organofunctional silane coupling agent in the outer layer portion of the proppant coating is preferably chosen to expose functionalities that will be reactive towards similar functionalities of adjacent and similarly coated proppants so that, when introduced downhole, these proppants form interparticle bonds at the temperatures and crack closure pressures found downhole in fractured strata. Such enhanced interparticle bonding helps keep the proppant in the fracture and maintains conductivity with reduced flowback. The invention also helps proppants designed for low temperature well to bond more firmly and allows proppants designed for high temperature wells to bond well even at lower downhole temperatures, thereby extending their useful range.
B32B 5/16 - Layered products characterised by the non-homogeneity or physical structure of a layer characterised by features of a layer formed of particles, e.g. chips, chopped fibres, powder
C09K 8/80 - Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open
C09K 8/68 - Compositions based on water or polar solvents containing organic compounds
The disclosure generally refers to a continuous mixer, which can be used in the production of coated particles, such as proppants used in hydraulic fracturing techniques.
B05D 1/00 - Processes for applying liquids or other fluent materials
C09K 8/80 - Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open
B01F 7/00 - Mixers with rotary stirring devices in fixed receptacles; Kneaders
B01F 7/04 - Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a horizontal or inclined axis with paddles or arms
Coatings and compositions for coating particulates are described that can be used as, for example, as proppants to, for example, extract oil and gas from subterranean formations. The coatings can be, for example, an inner coating adjacent to the particulate comprising a polyurethane and an outer coating comprising an polyurethane dispersion; a coating comprising a polyurethane admixed with a polyurethane dispersion; or a polyurethane dispersion layer and is free of an inner polyurethane layer.
Compositions and methods for coated or uncoated particulates, such as proppants, are provided that can, among other things, provide a hydrophobic surface that can enhance well productivity and other compositions and methods are disclosed.
Proppants for use in fractured or gravel packed/frac packed oil and gas wells are provided with a contaminant removal component to remove one or more of the contaminants found in subterranean water/hydrocarbon from a production well. The water/hydrocarbon cleaning proppant solids may be used as discrete particles in a proppant formulation, as a coating on proppant solids in pores of a porous proppant solid or as part of the proppant's internal structure. The contaminant removal component removes contaminants, especially dissolved contaminants, in the subterranean water or hydrocarbon before the water/hydrocarbon leaves the well. For those contaminant removal components that can be regenerated, such as ion exchange resins, a measured quantity of an acidic regeneration solution can be injected into the fractured stratum for regeneration and recovered when the well resumes production.
E21B 43/267 - Methods for stimulating production by forming crevices or fractures reinforcing fractures by propping
C09K 8/80 - Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open
C09K 8/536 - Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning characterised by their form or by the form of their components, e.g. encapsulated material
C09K 8/90 - Compositions based on water or polar solvents containing organic compounds macromolecular compounds of natural origin, e.g. polysaccharides, cellulose
C09K 8/68 - Compositions based on water or polar solvents containing organic compounds
Compositions and methods for coated or uncoated particulates, such as proppants, are provided that can, among other things, provide a hydrophobic surface that can enhance well productivity and other compositions and methods are disclosed.
C09K 8/68 - Compositions based on water or polar solvents containing organic compounds
E21B 43/267 - Methods for stimulating production by forming crevices or fractures reinforcing fractures by propping
E21B 43/26 - Methods for stimulating production by forming crevices or fractures
C09K 8/80 - Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open
C09K 8/536 - Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning characterised by their form or by the form of their components, e.g. encapsulated material
Solid proppants are coated with a coating that exhibits the handling characteristics of a pre-cured coating while also exhibiting the ability to form particle-to-particle bonds at the elevated temperatures and pressures within a wellbore. The coating includes a substantially homogeneous mixture of (i) at least one isocyanate component having at least 2 isocyanate groups, and (ii) a curing agent comprising a monofunctional alcohol, amine or amide. The coating process can be performed with short cycle times, e.g., less than about 4 minutes, and still produce a dry, free-flowing, coated proppant that exhibits low dust characteristics during pneumatic handling but also proppant consolidation downhole for reduced washout and good conductivity. Such proppants also form good unconfined compressive strength without use of an bond activator, are substantially unaffected in bond formation characteristics under downhole conditions despite prior heat exposure, and are resistant to leaching with hot water.
C09K 8/80 - Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open
C09K 8/536 - Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning characterised by their form or by the form of their components, e.g. encapsulated material
B05D 3/00 - Pretreatment of surfaces to which liquids or other fluent materials are to be appliedAfter-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
B05D 7/24 - Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials for applying particular liquids or other fluent materials
The invention relates to a propped, fractured, subterranean field with (a) a first proppant and (b) a second proppant that exhibits a relatively higher average crush strength and/or an ability to form a particle to particle bonded structure than the first proppant. Preferably, the first proppant is uncoated sand and the second proppant is resin-coated sand. The proppants can be deposited as a substantially homogeneous mixture or in layered structures (vertical or horizontal) within the fractured field. Deformation of the second proppant under closure stress acts to spread out the compression pressures in a mixture so as to reduce failure of the first proppant. Similar protective effects are found when the proppants are deposited in layers. When formed as vertical pillar structures, the second proppant structures can also act as in-situ screens that inhibit formation fines from migrating through the proppant pack to the detriment of field conductivity.
Polymer-coated proppants for hydraulic fracturing of oil and gas wells have an outer layer portion that comprises an organofunctional coupling agent, preferably an organofunctional silane coupling agent. The use of an organofunctional silane coupling agent in the outer layer portion of the proppant coating is preferably chosen to expose functionalities that will be reactive towards similar functionalities of adjacent and similarly coated proppants so that, when introduced downhole, these proppants form interparticle bonds at the temperatures and crack closure pressures found downhole in fractured strata. Such enhanced interparticle bonding helps keep the proppant in the fracture and maintains conductivity with reduced flowback. The invention also helps proppants designed for low temperature well to bond more firmly and allows proppants designed for high temperature wells to bond well even at lower downhole temperatures, thereby extending their useful range.
C09K 8/80 - Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open
B32B 5/16 - Layered products characterised by the non-homogeneity or physical structure of a layer characterised by features of a layer formed of particles, e.g. chips, chopped fibres, powder
C09K 8/68 - Compositions based on water or polar solvents containing organic compounds
Proppants for use in fractured or gravel packed/frac packed oil and gas wells are provided with a contaminant removal component to remove one or more of the contaminants found in subterranean water/hydrocarbon from a production well. The water/hydrocarbon cleaning proppant solids may be used as discrete particles in a proppant formulation, as a coating on proppant solids in pores of a porous proppant solid or as part of the proppant's internal structure. The contaminant removal component removes contaminants, especially dissolved contaminants, in the subterranean water or hydrocarbon before the water/hydrocarbon leaves the well. For those contaminant removal components that can be regenerated, such as ion exchange resins, a measured quantity of an acidic regeneration solution can be injected into the fractured stratum for regeneration and recovered when the well resumes production.
E21B 43/267 - Methods for stimulating production by forming crevices or fractures reinforcing fractures by propping
C09K 8/80 - Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open
C09K 8/68 - Compositions based on water or polar solvents containing organic compounds
C09K 8/536 - Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning characterised by their form or by the form of their components, e.g. encapsulated material
C09K 8/90 - Compositions based on water or polar solvents containing organic compounds macromolecular compounds of natural origin, e.g. polysaccharides, cellulose
Proppants for hydraulic fracturing of oil and gas wells are coated with a polyurea-type coating. In a preferred embodiment, the polyurea-type coating is formed by contacting a polymeric isocyanate with an amount of water and a blowing catalyst at a rate and quantity sufficient to generate a reactive amine in situ on the outer surface of the proppant which thereby reacts with unconverted polymeric isocyanate to form a thin polyurea-type surface coating that is substantially solid and lacks foam or substantial porosity. Alternatively, the polyurea-type can be produced by selecting reactive amine compounds and isocyanates to develop the coated proppant. The coated proppants retain the discrete, free-flowing character of the original core solids but with the beneficial effects of the polyurea-type coating of the present invention.
Proppants for hydraulic fracturing of oil and gas wells have a polymeric coating that is strengthened with reinforcing particulates that are reactive with, or chemically bonded to, the polymeric proppant coating. Preferably, these particulates are added into the coating during the coating process. In one embodiment, functionalized particulates are used that become grafted into the polymer of the proppant coating through the chemical functionality imparted to the particulates. If non-functionalized particulates are used, a coupling agent is preferably added to enhance the bond strength between the added particulates and the polymeric matrix of the proppant coating.
C09K 8/60 - Compositions for stimulating production by acting on the underground formation
C09K 8/588 - Compositions for enhanced recovery methods for obtaining hydrocarbons, i.e. for improving the mobility of the oil, e.g. displacing fluids characterised by the use of specific polymers
C09K 8/524 - Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning organic depositions, e.g. paraffins or asphaltenes
C09K 8/80 - Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open
Solid proppants are coated in a process that includes the steps of: (a) coating free-flowing proppant solids with a first component of either a polyol or an isocyanate in mixer; (b) adding a second component of either an isocyanate or a polyol that is different from the first component at a controlled rate or volume sufficient to form a polyurethane coating on the proppant solids; and (c) adding water at a rate and volume sufficient to retain the free-flowing characteristics of the proppant solids.
Solid proppants are coated with a coating that exhibits the handling characteristics of a pre-cured coating while also exhibiting the ability to form particle-to-particle bonds at the elevated temperatures and pressures within a wellbore. The coating includes a substantially homogeneous mixture of (i) at least one isocyanate component having at least 2 isocyanate groups, and (ii) a curing agent comprising a monofunctional alcohol, amine or amide. The coating process can be performed with short cycle times, e.g., less than about 4 minutes, and still produce a dry, free-flowing, coated proppant that exhibits low dust characteristics during pneumatic handling but also proppant consolidation downhole for reduced washout and good conductivity. Such proppants also form good unconfined compressive strength without use of an bond activator, are substantially unaffected in bond formation characteristics under downhole conditions despite prior heat exposure, and are resistant to leaching with hot water.
C09K 8/60 - Compositions for stimulating production by acting on the underground formation
E21B 43/267 - Methods for stimulating production by forming crevices or fractures reinforcing fractures by propping
C09K 8/80 - Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open
B05D 3/00 - Pretreatment of surfaces to which liquids or other fluent materials are to be appliedAfter-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
B05D 7/24 - Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials for applying particular liquids or other fluent materials
Proppants for use in fractured or gravel packed/frac packed oil and gas wells are provided with a contaminant removal component to remove one or more of the contaminants found in subterranean water/hydrocarbon from a production well. The water/hydrocarbon cleaning proppant solids may be used as discrete particles in a proppant formulation, as a coating on proppant solids in pores of a porous proppant solid or as part of the proppant's internal structure. The contaminant removal component removes contaminants, especially dissolved contaminants, in the subterranean water or hydrocarbon before the water/hydrocarbon leaves the well. For those contaminant removal components that can be regenerated, such as ion exchange resins, a measured quantity of an acidic regeneration solution can be injected into the fractured stratum for regeneration and recovered when the well resumes production.
Solid proppants are coated with a phenol-urethane coating in one or more layers by a method comprising coating a proppant solid and then curing the coated proppant under conditions sufficient to substantially cure said proppant, wherein said coating comprises a substantially homogeneous mixture of (i) an isocyanate component having at least 2 isocyanate groups, (ii) an amine reactant, and optionally (iii) an amine that is a latent curing agent for said isocyanate.
Solid proppants are coated with a coating that exhibits the handling characteristics of a precured coating while also exhibiting the ability to form particle-to-particle bonds at the elevated temperatures and pressures within a wellbore. The coating includes a substantially homogeneous mixture of (i) at least one isocyanate component having at least 2 isocyanate groups, and (ii) a curing agent. The coating process can be performed with short cycle times, e.g., less than about 4 minutes, and still produce a dry, free-flowing, coated proppant that exhibits low dust characteristics during pneumatic handling but also proppant consolidation downhole for reduced washout and good conductivity.
patents
