Global biopolymers market to witness a CAGR of 15.2% during 2018-2024: Energias Market Research Pvt Ltd.

Abstract

The use of Produced Water Xanthan (PWX) as a chemical flooding metabolite for Enhanced Oil Recovery (EOR) is described. PWX was synthesized by Xanthomonas campestris in a culture medium containing produced water from oil wells and crude glycerin. PWX key physico-chemical properties for application as an EOR agent are investigated and comparisons between PWX and SigmaTM Xanthan Gum (SXG) are given. X-ray spectra indicate the presence of Zn and Fe atoms in PWX. Rheological analyses show that both polymers exhibit non-Newtonian, pseudoplastic behaviour in solution. While SXG shows a reverse linear relationship between apparent viscosity and temperature, PWX may behave as a thermoviscosifying polymer (TVP). However, viscosities of PWX at 0.7% w/w and of SXG at 0.5% w/w are comparable above 60 °C. The critical polymer concentrations at 65 °C for SXG and PWX are 0.47% and 0.59%, respectively. Polymeric solutions of either xanthan gums were then tested as EOR fluids in carbonate plugs by considering the time of polymer injection: early injection is taken as a secondary oil recovery and late injection as a tertiary recovery. Increase in oil recoveries were similar for PWX and SGX when the injected solutions had the same viscosity. Because late injection requires the injection of a non-polymeric solution before flooding polymer, early injection required much less water to reach the same recovery factor. Also, the oil recovery increased when salt was added to a SXG or PWX solution, indicating that factors other than the water/oil viscosity ratio play a role in oil recovery. Having nearly the same viscosity, polymeric solutions of 0.7% w/w PWX and 0.5% w/w SXG in water, both with NaCl at 0.6% w/w, were tested as EOR fluids in tertiary recovery, under the same experimental conditions, leading to increases in oil recovery of 11% for SXG and 19% for PWX. Because Xanthomonas campestris only yields significant amounts of PWX in low salinity and aerobic conditions, PWX may be effective as an ex-situ Microbial Enhanced Oil Recovery metabolite. Once PWX is obtained from industrial wastes, it is environmentally friendlier than commercial xanthan gums.