Injection Modeling Simulation in a Geothermal Exploitation Site in Korea

Abstract

This study is to design injection well to recharge in a deep geothermal fluid supply. A borehole is drilled to the depth of 1,300m to use geothermal fluid in Pohang, Korea. The water table around the pumping well is at about 30m depth and the pump is located at 400m depth. After twenty-four hours' pumping test by 377 m3/day the ground water table is lowered more than 200m and showed very low recovery rate. According to the well logging data obtained 72 hours after pumping shut down, bottom water temperature is about 55 degree Celsius and EC is 5,000 microS/cm. In order to maintain the insistent supply of the geothermal fluid, we planed to install injection well. By the ground water modeling between injection well and withdraw well, we simulated the temperature distribution according to pumping rate in transient and steady state condition by using FEFLOW model.