Development of an Environmental-Friendly Wax Inhibitor for Crude Oil Transport in Oil and Gas Pipelines
Abstract
Wax deposition has caused significant operational problems and economic losses for many oil and gas companies. Typically, crude oil is transported at conditions below Wax Appearance Temperature (WAT) causing wax to precipitate and build up leading to flow restriction and sometimes eventual pipe blockage. Wax inhibitors (WI) have been known to be a formidable solution to this problem. However, conventional wax inhibitors are known to have caused environmental and health concerns due to their toxicity. They could also be quite expensive therefore, the need to develop economically attractive and environmentally friendly WI. In this study, a wax inhibitor Methanol-Cellulose (WI-MC) was formulated from coconut husk bio raw material. The coconut husk was treated and prepared in the laboratory and applied at different dosages of 0.2ml, 0.6ml and 1.0ml to two different crude oil samples. The effect on WAT examined from viscosity readings obtained at varying temperature was compared with Toluene. Without inhibitor the WAT for samples A and B was 55°C. Comparative analysis however reveals WI-MC is comparable with Toluene. At 0.2ml dosage, WI-MC had no effect on WAT whereas at 0.6 and 1.0ml, the temperature-viscosity plot showed WAT lowered to 50°C, Similar result was also obtained for Toluene. This indicates WI-MC inhibitor can be considered a feasible and potentially cost-effective alternative for synthetic and imported WIs. The reduced dependence on such chemicals is an environmental advantage brought about by renewable and locally available materials.
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