Recent experimental studies show that fines migration effect in sandstone rocks is more prominent at higher temperature. However, increased fines migration is generally attributed to temperature dependant zeta potential. In this study, laboratory studies were designed to investigate if mineral dissolution induced more fines migration at high temperatures.
In this experimental study, Berea sandstone core samples are used and performed single-phase flooding experiments at three temperatures, 25°C, 50°C and 70°C. Core samples are characterized using X-Ray Powder Diffraction (XRD) and X-Ray Fluorescence (XRF) before the flooding experiments. Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS) analysis are also conducted to identify the changes of rock surface before and after the flooding experiments. All core samples are subjected to single-phase injections of water at salinities 40, 10, 2.5, 0.5 and 0g/L NaCl. To calculate permeabilities, pressure drops are recorded using pressure transducer during the flooding experiments. The produced water is collected and used to measure the concentration of produced fines. Inductively coupled plasma-optical emission spectrometry (ICP-OES) is applied to analyze the types of produced minerals in each experiment.
The analysis of produced water showed that an increase in Ca ions at 50°C and 70°C. Chemical reation led to dissolution of carbonate minerals increasing pore opening. Therefore, the permeability damage due to fines migration is less pronounced at high temperatures.
