Production and Application of Schizophyllan in Microbial Enhanced Heavy Oil Recovery

Abstract

Generally partially hydrolyzed polyacrylamides (HPAM) are used worldwide for polymer-based oil recovery processes. However there aree some problems associated with HPAM applications such as, treatment of produced water, oil-water separation and toxicity issues associated with degradation products of HPAM. Schizophyllan biopolymer is biodegradable and environmental friendly alternative to chemical polymers used for EOR applications. In present work we studied the schizophyllan production by fungi Schizophyllum commune ATCC38548, its structural characterization and potential applications in Microbial Enhanced Heavy Oil Recovery (MEOR). Different minimal production media containing carbohydrate based carbon sources were screened for better biopolymer production. During the course of experiments we studied microbial growth profile, biopolymer production, and rheological properties of biopolymer, chemical characterization and application of biopolymer in enhancing heavy oil recovery using Berea sandstone cores. The biopolymer was produced in significant quantities and increased the viscosity of the production medium after 9 days of incubation. Viscosities were measured using rheometer at different shear rates (0.1-100 s-1) and temperatures, where it was found to be isothermal over a wide range of temperature with strong shear thinning behavior. After 14 days of incubation, the viscosity was 21535 – 43 cP at shear rate from 0.1 – 100 s-1, respectively. Thermogravimetric analysis (TGA) analysis showed that the moisture content in purified biopolymer was 6.3%; it was quite stable till 100-200 °C and melted at temperatures higher than 250 °C. It was characterized as schizophyllan by MALDI-TOF-MS and NMR (1H and proton decoupled 13C NMR) analysis. The repeating tetrasaccharide unit of schizophyllan structure comprised of homoglucan with β-1, 3-linked backbone and single β-1, 6-linked laterally glucose side chains at every third residue. The biopolymer was used for MEOR experiments at 45 °C, using Berea sandstone core plugs. The biopolymer injection resulted in 28% additional heavy oil recovery over residual oil saturation (Sor).

Production, Characterization, and Application of Bacillus licheniformis W16 Biosurfactant in Enhancing Oil Recovery

“…None of the media showed much increase in the viscosities even after 72 h, and the viscosities varied between 1.3 and 1.5 mPa s, for both abiotic controls and experimental samples. The viscosities of some of the biopolymers are reported to be in the range of 43–21535 cP (Joshi et al, 2016). Hence, it was concluded that this isolate B. licheniformis W16 produced only biosurfactant and not biopolymer, under tested environmental conditions in these nine minimal media.…”

The biopolymer produced by Rhizobium viscosum CECT 908 is a promising agent for application in microbial enhanced oil recovery

“…A variety of microorganisms produce biopolymers useful for application in MEOR, including species belonging to the genera Alcaligenes, Aureobasidium, Bacillus, Leuconostoc, Pseudomonas, Sphingomonas and Xanthomonas [1,4,12,[20][21][22][23][24]. Among these biopolymers, xanthan gum, produced by the bacterium Xanthomonas campestris, stands out.…”

Investigation of Natural Mucilage for Enhanced Oil Recovery: the Potential of Corchorus Olitorius Hydrocolloid

“…This behavior is primarily attributed to the increased molecular mobility and reduced intermolecular forces within the natural polymer chains. , Consequently, the viscosity of the polymer decreases as it becomes easier for the chains to slide past each other. The viscosity of polymer solutions with polysaccharides depends on various parameters such as molecule structure, concentration, and the presence of other substances.…”

“…These results could be compared with 20% of additional oil recovery after 1 PV of C. olitorius, as for the experiment conducted by Joshi et al (2016) six times more polymer solution was used …”

“…2016) six times more polymer solution was used. 36 Another core flooding experiment of Guar gum injection into a sandpack showed satisfactory results on additional oil recovery. After injection of 0.5 PV of 2000 ppm, Guar gum oil recovery increased to 15.7% from water flooding, which was 55% from the original oil in place.…”