Investigation of friction reduction in high turbulent flows by different polymer additives
Industrial applications such as hydraulic fracturing require large flowrates and pressure resulting in high energy consumption and costs. To mitigate these concerns, dilute concentrations of friction reducers (i.e., polymers, and surfactants) are used to reduce the pressure drop (therefore friction) in the solvent operating under turbulent flow conditions resulting in lower energy consumption, and costs. These applications are also present in other industrial applications such as marine transportation, firefighting, and heating & cooling systems, where friction reducers have been employed to reduce the friction by over 80% in these industrial processes. In this study, the friction reducing performance of a commonly used friction reducer, Partially Hydrolyzed Polyacrylamide (HPAM), was investigated in a friction flow loop. While HPAM is inexpensive, environmentally friendly and an effective friction reducer in fresh water, HPAM degrades irreversibly due to high flow rates (shear), and salts present in brine. As a result, HPAM was mixed with polyethylene oxide (PEO), and xanthan gum (XG) to improve the friction reduction (FR) peak performance, shear stability and salt-tolerance of HPAM., The novelty of this work is to analyze the effects and mechanisms of friction reducing polymer mixtures in brine solutions and high turbulent flows similar to what is present in the field. The interesting finding was that HPAM-PEO and HPAM-XG mixtures improved the FR performance of HPAM in brine at a greater rate than in tap water. It was investigated that brine solutions enhance the likelihood of intermolecular interactions of the polymer mixtures than in tap water resulting in the improved FR performance; the correlation between the FR and the intermolecular associations between HPAM with PEO and XG has not been reported in literature. Evidence of intermolecular interactions between HPAM with PEO and XG was found using Fourier transform infrared spectroscopy (FTIR). In addition, two degradation models were used confirming that XG improves the degradation resistance of HPAM. Lastly, it was shown that PEO, and XG reduce the consumption of HPAM required achieve an optimal FR performance, thus transitioning towards alternate, eco-friendly FR additives.
friction reduction, drag reduction, polymers, polymer mixtures, hydraulic fracturing
Bakir, M. (2021). Investigation of friction reduction in high turbulent flows by different polymer additives (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.