Power generation from low temperature heat recovery

Most of the heat recovery systems are designed at medium temperature (200-350 degrees C) and high temperature (350-500 degrees C) levels. Abundant amount of heat is rejecting in the temperature range of 100-150 degrees C. Organic Rankine cycle (ORC) and Kalina cycle system (KCS) are the prominent technologies to tap the heat at this level. In the proposed Organic flash cycle (OFC), partial amount of preheated liquid is flashed into wet vapor and followed by separation into liquid and vapor against the full flashing in geothermal power plant. The separated vapor is mixed with turbine streams for power augmentation. The work is focused on current technologies and comparative study to highlight the potential configuration suitable to low temperature heat recovery. R124 fluid is selected for ORC and OFC in the comparative study. The source temperature and heat recovery vapor generator's (HRVG) pressure are varied in the comparative study of ORC, OFC and KCS. On overall basis OFC has been recommended for maximum power generation through more heat recovery.