Question

Problem 3 (50%) The process below is part of a larger steam power plant. Steam in stream 1 enters the turbine at 600 °C, 50 bar with mass flow rate kg/s and exits at 7 bar, 350 °C. Stream 3, which is saturated liquid and is throttled to 2 bar (stream 4). Stream 5 is at 200°C, 2 bar, and is mixed adiabatically with stream 4 in the tank. Stream 6 is wet steam that contains 8% liquid. This stream is cooled in heat exchanger 2 and exits as saturated liquid (stream 7). The efficiency of the pump is 85% a) Fill out the table below with the properties of all streams. Indicate the phase as "s/h V" (superheated vapor), "c/L" (compressed liquid) and if the state is a vapor/liquid mixture, indicate the mass fraction of the liquid. b) Calculate the efficiency of the turbine. c) Calculate the absolute amount of heat that is exchanged between the hot and cold streams in heat ex changer l d) Calculate the heat in heat exchanger 2. e) Calculate the work in the pump Summarize your results in the table below but you must show your work to receive credit. heat exchnager 2 pummp (kg/s) T (C) P (bar) H (kJ/kg) S (kJ/kg K) phase Turbine efficiency Heat in heat exchanger 1 (kJ/s) Heat in heat exchanger 2 (kJ/s) Work in pump (kJ/s)

Answer 1