Effect of proppant treatment on heat extraction performance in enhanced geothermal system

Abstract

Geothermal energy, a clean renewable energy, is widely used for electricity generation. Hydraulic fracturing treatment is a potential way to effectively develop the geothermal energy in deep formation. The design of the proppant pumping schedule is a key factor, which affects the permeability and the consequent heat extraction in the hot dry rock formation. In this paper, we proposed a comprehensive model to investigate the effect of proppant pumping schedule on the heat extraction. The model was validated by an analytical solution. After that, we presented a basic case to investigate the proppant distribution and heat extraction in the reservoir. Meanwhile, we designed a series of cases to investigate the effects of physical parameters in proppant pumping design on the heat extraction. Based on case studies, some useful insights into hydraulic fracturing design for the efficient development of geothermal energy in the deep formation were obtained and summarized. This paper provides a comprehensive model to simulate the proppant transport and heat extraction in the geothermal reservoir in a field scale. Meanwhile, the case studies can give clear insights about the effect of proppant pumping schedule on the heat extraction. • A field-scale model was proposed to investigate the effect of proppant pumping schedule on the heat extraction. • Comparison of heat extraction among matrix with propped-fractures, non-propped fractures, and no fractures was performed. • Effects of physical parameters in proppant pumping design on the heat extraction were investigated. • Useful insights into hydraulic fracturing design for the effective development of geothermal energy were summarized.