Laboratory-Scale Experimental Study on the Injection-Production Performance of a Multilateral-Well Enhanced Geothermal System

Instituting a multilateral-well enhanced geothermal system is a novel method to enhance fluid injectivity and productivity for geothermal development by using lateral wells. To study the influencing laws of different factors of the system oninjection-production performance, fluid flow and heat transfer experiments for multilateral-well were conducted. Experiments were performed to evaluate the injection-production performance and investigate the effects of different factors on the injectivity and productivity of lateral wells based on the multilateral-well enhanced geothermal experimental system and artificial rock samples. In addition, the injection-production performances of a multilateral well and a single vertical well were compared. Results indicated that decreasing the injection temperature can increase injection pressure and improve injectivity of the system, while increasing the number of lateral-wells and length can decrease the injection pressure and increase the outlet flow rate.The injection-production performance of the multilateral-well enhanced geothermal system is much better than that of the single-vertical-well geothermal system, and is more suitable for the development and injection of the geothermal energy. Findings prove that multilateral well can enhance the injectivity and productivity of the geothermal system, providing a theoretical foundation and guidance for field applications of the multilateral-well enhanced geothermal system.