Evaluations of the effect of selected wax inhibitive chemicals on wax deposition in crude oil flow in sub-sea pipe-lines

Comparative studies were made on the effect of different wax inhibitive chemicals on the wax deposition volume during crude oils flow in pipeline. Two crude oils from Ovhor and Jisike oil fields in the southern part of Nigeria were used in the study. The four identified chemicals: Alkyl sulphonates (wax dispersant), polyethylene (wax inhibitors/crystal modifier), acrylate ester copolymer (pour point depressant, PPD) and xylene (wax solvents) inhibit wax deposition to varying degree of between 14.6–44.9% for crude oil A, and between 21.6–41.4% for crude oil B when 1500 ppm of each chemical was mixed with the crude oil sample. The optimal wax inhibition formulation of polyethylene, xylene, acrylate ester polymer and alkyl sulphonate contains 40.4, 19.2, 27.6, 12.8% and 36.3, 21.5, 25.8, 16.4% for crude oil A and B respectively. Applications of the optimal formulated mixtures of the above chemicals inhibit wax deposition by 58.9% and 62.4% for crude oil A and B respectively.