摘要

Increasing attention has been paid to the power generated by utilizing hot fluids that are co-produced from oil and gas reservoirs, as well as other geothermal resources. It is thus essential to evaluate the geothermal resource in oil and gas reservoirs accurately. Although there are a number of approaches for determining the geothermal resource associated with oil and gas fields, a lot of problems are yet to be solved. Previous studies on the effects of oil and gas saturation on the geothermal resource were considered; however, it was assumed that the oil and gas saturations were constant during the development, which is not true. To this end, the existing volumetric approach of evaluating geothermal resource in oil and gas reservoirs was modified by considering the change of oil and gas saturation with time. An oil reservoir from Huabei oilfield with a moderately high temperature was chosen as a target reservoir to apply the modified method. The effects of porosity, oil and gas saturations, and reservoir rock type on the geothermal resource were studied and the results compared to existing approaches. Also, the possible energy and income that might be generated from this geothermal system were estimated. The results indicate that the geothermal resource, energy, and possible income have been overestimated by the existing models, and the difference becomes more significant as the oil or gas saturation increases.