Consider a 15 MW biomass thermal power plant. The steam generator produces vapor at 80 bar...

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Consider a 15 MW biomass thermal power plant. The steam generator produces vapor at 80 bar and 400C. Some of steam expands through the first turbine stage to 5 bar and the remainder is directed to the heat exchanger. The steam exiting the first turbine stage enters the flash chamber. Saturated vapor and saturated liquid at 5 bar exit the flash chamber as separate streams. The vapor is reheated in the heat exchanger to 320C before entering the second turbine stage. The de-aerator (open feed-water heater) operates at 10 bar, and the condenser pressure is 0.06 bar. Each turbine stage has an isentropic efficiency of 88%. The boiler and generator efficiencies are 85% and 98%, respectively. HP Turbine 2 Biomass boiler Flash Chamber 3 LP Turbine Generator Heat Exchanger 5 W 8 10 Steam trap 6 Boiler feed pump De-aerator 9 7 Condensate pump Condenser Illustrate the cycle on a temperature-entropy diagram identifying all the state points. Prepare a "heat balance diagram" for the power plant and hence determine the overall net electric heat rate. [Max 1 answer book]. Hint: The four properties (i.e. pressure, temperature, mass flow rate and enthalpy) required on the "heat balance diagram" for each state point can be put into a property table. Consider a 15 MW biomass thermal power plant. The steam generator produces vapor at 80 bar and 400C. Some of steam expands through the first turbine stage to 5 bar and the remainder is directed to the heat exchanger. The steam exiting the first turbine stage enters the flash chamber. Saturated vapor and saturated liquid at 5 bar exit the flash chamber as separate streams. The vapor is reheated in the heat exchanger to 320C before entering the second turbine stage. The de-aerator (open feed-water heater) operates at 10 bar, and the condenser pressure is 0.06 bar. Each turbine stage has an isentropic efficiency of 88%. The boiler and generator efficiencies are 85% and 98%, respectively. HP Turbine 2 Biomass boiler Flash Chamber 3 LP Turbine Generator Heat Exchanger 5 W 8 10 Steam trap 6 Boiler feed pump De-aerator 9 7 Condensate pump Condenser Illustrate the cycle on a temperature-entropy diagram identifying all the state points. Prepare a "heat balance diagram" for the power plant and hence determine the overall net electric heat rate. [Max 1 answer book]. Hint: The four properties (i.e. pressure, temperature, mass flow rate and enthalpy) required on the "heat balance diagram" for each state point can be put into a property table.