CHARACTERIZATION OF SLUDGE WAXES FROM CRUDE-OIL STORAGE TANKS HANDLING OFFSHORE CRUDE

The 300 degrees C+ and 500 degrees C+ vacuum residues of the sludge ob tained from offshore crude oil storage tanks located at our onshore fa cilities have been subjected to dewaxing using MIBK solvent. The yield of the refined waxes were 45.38% and 43.13% (sludge basis) and meltin g points 92-93 degrees C and 95-96 degrees C respectively. The waxes w ere mainly n-paraffins. Their simulated boiling point distribution ana lysis reveals a distinct bimodal distribution of n-paraffins, the even carbon number homologues between C-50 to C-60 being present at prefer entially higher ratio (1.4:1) than the odd ones. The present finding a re expected to improve the understanding of waxes present in offshore crude. It is also expected to help in devising process to refine waxes of tank bottom sludge.