Evaluation of flaxseed hydrocolloid’s potential in improving oil recovery

Abstract

The use of natural materials to improve oil recovery and production is believed to be a suitable method. The current study examined hydrocolloids extracted from flaxseed as a viscosifying agent for improved and enhanced oil recovery EOR. It aimed to investigate the effect of concentration, temperature, salinity, and ageing time on the rheology of the flaxseed gel solution (FGS). The study also highlighted the solution’s performance at the core level for carbonate reservoirs. The FGS was successfully extracted by soaking and heating at 70 °C. Fourier-transform infrared (FTIR) spectroscopy results showed polysaccharide dominance in the mucilage. The rheology outcomes showed that the FGS was able to increase the water viscosity by 5–17 cp at 25 °C. Different concentrations of the FGS preserved its viscosity at temperatures of 25–45 °C. The salinity reduced the gel’s viscosity, especially above 2.5 wt%. A 50 g/L solution successfully tolerated all the tested salinities and the temperature range at all shear rates. A reduction in viscosity was observed during the first five days of ageing due to biological degradation caused by bacteria. Ageing had no major influence between 5 and 10 days. The FGS resulted in a 12 % incremental oil recovery. The sweep efficiency improved due to the 84 % mobility enhancement. This study confirms the possibility of deploying hydrocolloids as a natural viscosifier to improve the oil recovery in Kazakhstan’s oil reservoir conditions.