Reduction of Wax Deposit in Thai crude oil

Paraffin wax is naturally occurring in petroleum, large molecular weight wax can be precipitated due to temperature differences during transportation from down hole to surface, out shore to inshore and to production plants. The precipitation of wax reduces the internal diameter and eventually blocks the pipeline. The petroleum production companies pay millions U.S. dollars to solve the wax deposition problem. A chemical method is a technique that has been used to minimize the problem caused by the wax deposition. In this study, the influence of 7 different wax inhibitors and 2 different solvents on pour points of the three crude oils were investigated. The concentration of wax inhibitors were varied. The changes of properties were characterized by using differential scanning calorimeter(DSC), simulated-distillation GC(Sim-Dist GC) and ASTM pour point apparatus. Moreover the characteristics and properties of wax were also studied by two methods of solvent separation(Nguyen's method and Modified method). The results of wax inhibitors and solvent addition showed decrease of the pour point. However the amount of wax inhibitors used depended on the composition in each crude oil. Furthermore, the characterization(initial boiling point, wax content, wax appearance temperature(WAT), wax disappearance temperature(WDT) and pour point results) of the three crude oils were compared.