Design and development of the discharge system of IDDP-1

•IDDP-1 was discharged at intervals for almost 2 years.•Five different designs of discharge system were installed.•Measurements showed temperature up to 440°C, enthalpy up to 3200kJ/kg and flow up to 50kg/s.•Scaling, corrosion and erosion were observed in the discharge system.•The well was shut in July 24, 2012 after the master valves had failed. The initial discharge of IDDP-1 took place in March 2010 and the well was discharged intermittently until July 2012. In the beginning a mixture of steam and water flowed from the well but soon the fluid became superheated and enthalpy gradually increased, approaching 3200kJ/kg. The flow rate from the well was up to 50kg/s. The design condition at well head turned out to be challenging due to high pressure, temperature, corrosion and erosion. Valves, rated for higher pressure and temperature, failed during operation. Five different designs of discharge systems were installed. The well had to be quenched when the master valves failed. Plans for its future are still being evaluated.