Application of Novel Fruit Extract for Flow Assurance of Indian Field Waxy Crude Oil

Abstract

Summary This research article deals with the application of shikakai fruit (Senegalia rugata) extract (SE) used as a novel bio-additive for improving flow properties of waxy crude oil (WCO) to reduce pumping cost during pipeline transportation. SE was synthesized using solvent extraction method, which is one of the most common economic extraction processes. Bio-additive was characterized by Fourier transform infrared spectroscopy (FTIR) spectroscopy, carbon, hydrogen, nitrogen, sulfur (CHNS) analysis, gas chromatography-mass gas chromatography-mass spectroscopy (GC-MS), differential light scattering, and thermogravimetric analysis (TGA). Pour point of WCO was decreased by 12°C due to addition of 1,000 ppm of SE on crude oil. Viscosity of WCO reduced significantly after addition of a bio-additive. It was found that viscosity of SE beneficiated crude oil (1,000 ppm dosage) at 30°C is less than that of pure crude at 50°C. So, addition of SE may be an alternative of heating during flow of WCO. Microscopic studies confirm that wax and other solid particles become smaller and more dispersive so that the particles are not able to come closer and form a three-dimensional network. Consequently, flow becomes easier and pumping cost gets reduced. Experimental data related to viscosity better fitted with Casson model and Bingham model before addition of SE depict that significant yield stress is required to restart the flow of crude oil. Due to the addition of SE, yield stress was deceased significantly and crude oil beneficiated with bio-additive tends to behave like a Newtonian fluid. This article also investigates wax deposition through laboratory-designed wax depositional setup. The wax deposition of crude oil after addition of 1,000 ppm SE was comparatively 56 and 75% lower than untreated crude oil when deposition studies were performed for 2 and 4 hours, respectively, at 25°C. Wax crystals of SE-treated crude oil decreased in diameter and disoriented the particles, preventing the formation of three-dimensional networks so that crude oil can easily flow through pipelines. Considering the efficacy of extracted bio-additive and its cost effectiveness, the same can be applied for flow assurance of WCO through pipelines even at very low temperatures.