SELECTION OF OPTIMAL HYDRATE INHIBITOR SURFACTANTS FOR USE IN OIL AND GAS OPERATIONS

摘要

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.

主权项

1. A method comprising:
producing a bulk fluid from a subterranean formation, the bulk fluid comprising at least water and a hydrocarbon, and having constituent parameters selected from the group consisting of salinity (S), water volume (Wp), hydrocarbon concentration (x), equivalent alkane carbon number (EACN), surfactant concentration y, and ionic surfactant characteristic curvature (Cc) or nonionic surfactant characteristic curvature (Ccn); 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 according to Equation A for ionic surfactant compositions and Equation B for nonionic surfactant compositions:
HLD=ln(S)−k*EACN+cc−αT(T−25° C.)  Equation AHLD=b(S)−k*EACN+ccn−cT(T−25° C.)  Equation B,  where S is salinity of sampled fluid; b is a salinity constant; EACN is equivalent alkane carbon number for the hydrocarbon in the sampled fluid; T is temperature of the sampled fluid; cc is characteristic curvature for the ionic surfactant composition; ccn is characteristic curvature for the nonionic surfactant composition; αT is a surfactant temperature constant for the ionic surfactant composition; and cT is a surfactant temperature constant for the nonionic surfactant composition; 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.