PURPOSE: To prevent crude oil from emulsifying or dispersing in a desalter washing water by treating the washing water with a dispersion of a specified water-soluble cation polymer before the crude oil is added to the desalter.
CONSTITUTION: The desalter washing water containing crude oil is treated with a water-soluble cation polymer dispersion. The dispersion of the water-soluble cation polymer is produced by polymn. of a water-soluble monomer mixture containing at least 5 mol% of cation monomers expressed by the formula and at least 5 mol% of acrylamide or methacrylamide. In the formula, each of R1 and R2 is H or CH3, each of R2, R3 and R5 is a 1-2C alkyl group, R7 is H or a 1-2C alkyl group, each of A1 and A2 is O or NH, each of B1 and B2 is a 2-4C alkylene group or hydroxypropylene group, and each of X1- and X2- is a counter ion.
MAIKERU ERU BUREIDEN
DONARUDO JIEI NIYUUMAN
