Permeability and Porosity Changes in Sandstone Reservoir by Geothermal Fluid Reinjection: Insights from a Laboratory Study

Geothermal energy is a clean and environmentally friendly source that can be used sustainably; however, attention towards geothermal has been intermittent during the last 40 years as function of crisis oil price. However, reinjection clogging challenge limiting development utilization. In China, widely distributed sandstone reservoirs have reduced production due to technical constraints such excessive pressure blockage. this paper, we took Binzhou field in North China an example conducted displacement experiments under different temperature flow rate conditions by collecting situ fluid core rock obtain changes permeability. By comparing variation geochemical mineral composition fluids cores before after experiments, combined with water–rock interaction simulation, investigated reasons for permeability porosity. The results show high low relatively minimal pressure, 1.0 mL/min at 45 °C shows effect on permeability, while 55 0.5 Flow main factor controlling demonstrated minor effect. shift porosity mainly caused precipitation quartz conversion albite montmorillonite. injection may dissolved additional minerals change reduction greater than °C, indicating blockage, which led reduction, contains multiple causes, chemical physical blockages. From laboratory studies, recommended reinjected water cooled or kept below reservoir moderate conditions.