PURPOSE: To provide a method for removing a corrosive contaminant from a hydrocarbon fluid which can remove a water storage tank and improve contaminant removal efficiency by passing a mixture of a contaminant-contg. hydrocarbon fluid with water through a porous, hydrophobia, hollow fiber membrane and separating a filtrate stream from a retentate mixture.

CONSTITUTION: A corrosive contaminant-contg. halogenated hydrocarbon or hydrocarbon fluid contaminated with a corrosive ion is mixed with water to prepare a mixture. The mixture is introduced through an input 40 into a separation module 16 having a popularity of porous, hydrophobic hollow fiber membranes 34 housed in a plastic web 36 housed in a separation module 38 in a tangential direction relative to the surface of the hollow fiber membranes 34 and passed through the hollow fiber membranes 34 to remove a contaminant. The filtrate is then discharged through outputs 42, 44 and separated from a retentate mixture, while the retentate is discharged through an output 46.