A geothermal supply of hot water at 80 lbf/in 2, 300 F is

A geothermal supply of hot water at 80 lbf/in 2, 300 F is fed to an insulated flash evaporator at the rate of 10,000 lbm/h, A stream of saturated liquid at 30 lbf/in 2 is drained from the bottom of the chamber and a stream of saturated vapor at 30 lbf/in 2 is drawn from the top and fed to a turbine. The turbine has an isentropic efficiency of 70% and an exit pressure of 2 lbf/in 2. Evaluate the second law for a control volume that includes the flash evaporator and the turbine.