Abstract: Methods of providing an optimal surfactant or surfactant blend in a subterranean operation and obtaining a sampled fluid from a subterranean formation and determining constituent parameters of the sampled fluid using a hydrophilic-lipophilic deviation (HLD) model. The HLD model can be used to determine an optimal surfactant or surfactant blend to achieve an oil-water separation morphological phase of the sampled fluid. The optimal surfactant or surfactant blend can then be introduced into the subterranean formation as part of a surfactant flooding enhanced oil recovery operation.

Abstract: Methods including producing a bulk fluid from a subterranean formation, the bulk fluid comprising at least water and a hydrocarbon, and having certain constituent parameters; sampling a portion of the bulk fluid, thereby forming at least one sampled fluid; determining constituent parameters of the sampled fluid using the hydrophilic-lipophilic deviation (HLD) model; and determining an optimal hydrate inhibitor surfactant (HIS) or HIS mixture to achieve a first oil-water separation morphological phase of the sampled fluid at temperatures above about 10° C. and a first water-in-oil morphological phase of the sampled fluid at temperatures below about 5° C.

Abstract: Systems comprising a main tubular coupled to a pump and extending from a surface into a subterranean formation, wherein produced bulk fluid is pumped to the surface, and wherein the bulk fluid comprises at least water and a hydrocarbon, and has certain constituent parameters; a storage container for retaining the bulk fluid; a sampling tubular in fluid communication with the main tubular for sampling the bulk fluid, thereby forming at least one sampled fluid; and a dosing system coupled to the sampling tubular and configured to receive the sampled fluid, the dosing system configured to determine a constituent parameter of the sampled fluid, identify a type and concentration of separating surfactant to include in the bulk fluid to obtain a hydrophilic-lipophilic deviation (HLD) substantially equal to 0, and introduce the identified type and concentration of the separating surfactant into the storage container retaining the bulk fluid.

Abstract: Methods including the step of producing a bulk fluid from a subterranean formation, the bulk fluid comprising at least water and a hydrocarbon. The bulk fluid is then sampled to form at least one sampled fluid. Next, constituent parameters of the sampled fluid are determined using the hydrophilic-lipophilic deviation (HLD) model. The constituent parameters include the salinity (S) of the sampled fluid, the salinity constant (b); the equivalent alkane carbon number for the hydrocarbon in the sampled fluid (EACN); T is temperature of the sampled fluid; the characteristic curvature for an ionic surfactant composition (cc) or for a nonionic surfactant composition (ccn); the surfactant temperature constant for the ionic surfactant composition (?T) or for a nonionic surfactant composition (cT). Also determining an optimal surfactant or optimal surfactant blend to achieve an oil-water separation morphological phase distribution of the sampled fluid.

Abstract: Systems comprising a main tubular coupled to a pump and extending from a surface into a subterranean formation, wherein produced bulk fluid is pumped to the surface, and wherein the bulk fluid comprises at least water and a hydrocarbon, and has certain constituent parameters; a storage container for retaining the bulk fluid; a sampling tubular in fluid communication with the main tubular for sampling the bulk fluid, thereby forming at least one sampled fluid; and a dosing system coupled to the sampling tubular and configured to receive the sampled fluid, the dosing system configured to determine a constituent parameter of the sampled fluid, identify a type and concentration of separating surfactant to include in the bulk fluid to obtain a hydrophilic-lipophilic deviation (HLD) substantially equal to 0, and introduce the identified type and concentration of the separating surfactant into the storage container retaining the bulk fluid.

Abstract: Methods including obtaining a sampled fluid from a subterranean formation, the sampled fluid comprising at least water and a hydrocarbon, and having certain constituent parameters; determining constituent parameters of the sampled fluid using the hydrophilic-lipophilic deviation (HLD) model; determining an optimal surfactant or surfactant blend to achieve an oil-water separation morphological phase of the sampled fluid; and introducing the optimal surfactant or surfactant blend into the subterranean formation as part of a surfactant flooding enhanced oil recovery operation.

Abstract: Methods including the step of producing a bulk fluid from a subterranean formation, the bulk fluid comprising at least water and a hydrocarbon. The bulk fluid is then sampled to form at least one sampled fluid. Next, constituent parameters of the sampled fluid are determined using the hydrophilic-lipophilic deviation (HLD) model. The constituent parameters include the salinity (S) of the sampled fluid, the salinity constant (b); the equivalent alkane carbon number for the hydrocarbon in the sampled fluid (EACN); T is temperature of the sampled fluid; the characteristic curvature for an ionic surfactant composition (cc) or for a nonionic surfactant composition (ccn); the surfactant temperature constant for the ionic surfactant composition (?T) or for a nonionic surfactant composition (cT). Also determining an optimal surfactant or optimal surfactant blend to achieve an oil-water separation morphological phase distribution of the sampled fluid.

Abstract: Methods including producing a bulk fluid from a subterranean formation, the bulk fluid comprising at least water and a hydrocarbon, and having certain constituent parameters; sampling a portion of the bulk fluid, thereby forming at least one sampled fluid; determining constituent parameters of the sampled fluid using the hydrophilic-lipophilic deviation (HLD) model; and determining an optimal hydrate inhibitor surfactant (HIS) or HIS mixture to achieve a first oil-water separation morphological phase of the sampled fluid at temperatures above about 10° C. and a first water-in-oil morphological phase of the sampled fluid at temperatures below about 5° C.