Investigating Suitability of Microbial Derived Biosurfactant for Deliquefying Gas Well - An Experimental Approach

Abstract

Abstract Liquid loading in the gas well is becoming more challenging as the gas field matured and may eventually kill the well if the liquids are not continuously removed from the well. The common method used in preventing liquid loading is by injecting surface-acting agents or solvents termed surfactants into the well to reduce the interfacial energy and weight of the water molecule in the gas stream Most surfactants used in the oil and gas industry today are synthetically manufactured which are toxic to life and environmentally incompatible. This paper presents a formulation of biosurfactant solution derived from Pseudomonas Aeruginosa and Escherichia Coli bacteria isolated from crude oil which is environmentally safe and evaluates the suitability fordeliquefying matured gas well. Generally, biosurfactants have the capacity to reduce the surface tension of the liquid by adsorbing at the liquid-gas interface and create significantly less mass than the liquid droplets which can then be easily extracted from the walls of the wellbore and assure flow in the gas system. In this study, the formulated biosurfactant was characterized for its physicochemical properties using scanning electron, microscopy (SEM), energy display spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR). A specific experimental design was set up and used to evaluate the unloading efficiency of the formulated biosurfactant and then contrasted with Sodium Lauryl Sulphate, a widely used commercial surfactant (SLS). The bulk foam stability was tested, and the results obtained proved that biosurfactant from (Escherichia Coli) provided more stable foams (57.10%, 65.7%, 80.03%) as compared with commercial surfactant (SLS) (60.85%, 74.5%, 83.10%.) and biosurfactant from Pseudomonas Aeruginosa (12.85%, 8.57%, 4.28%) in the surfactant concentration of 30wt%, 40wt% and 50wt%. Also, the biosurfactant produced from Pseudomonas Aeruginosa and Escherichia Coli bacteria reduces the surface tension from which value of 65 mN/m to 48.4 mN/m and 21.9 mN/m respectively, compared to the commercial surfactant (SLS) value of 19.6 mN/m. This study has revealed that the two biosurfactants derived can create foam through which they decrease the density of the film at the wall, and alter the equilibrium between the gravitational force and the interfacial friction, hence making an easy transition between the churn flow and the annular flow to achieve at a lower flow rate. However, the biosurfactant produced from Escherichia Coli bacteria gave better surface tension results than biosurfactant from Pseudomonas aeruginosa and the results are closer to that of surfactant Sodium Lauryl Sulphate, a widely used commercial surfactant (SLS) used for validation.