Consider a cogeneration power plant that is modified with reheat and that produces 3 MW of power and supplies 7 MW of process heat. Steam enters the high-pressure turbine at 8 MPa and 500°C and expands to a pressure of 1 MPa. At this pressure, part of the steam is extracted from the turbine and routed to the process heater, while the remainder is reheated to 500°C and expanded in the low-pressure turbine to the condenser pressure of 15 kPa. The condensate from the condenser is pumped to 1 MPa and is mixed with the extracted steam, which leaves the process heater as a compressed liquid at 120°C. The mixture is then pumped to the boiler pressure. Assuming the turbine to be isentropic, show the cycle on a T-s diagram with respect to saturation lines, and disregarding pump work, determine (a) the rate of heat input in the boiler and (b) the fraction of steam extracted for process heating.
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- An ideal cogeneration steam plant is to generate power and 9400 kJ/s of process heat. Steam enters the turbine from the boller at 7 MPa and 500°C. One-fourth of the steam is extracted from the turbine at 600 kPa pressure for process heating. The remainder of the steam continues to expand and exhausts to the condenser at 10 kPa. The steam extracted for the process heater is condensed in the heater and mixed with the feedwater at 600 kPa. The mixture is pumped to the boiler pressure of 7 MPa. (5) ↑ Boiler Pump II 6 O process process Process heater (3) Turbine (D) Condenser Pump I Show the cycle on a T-s diagram with respect to saturation lines. (8) 1arrow_forwardAn Ideal cogeneration steam plant is to generate power and 9400 kJ/s of process heat. Steam enters the turbine from the boller at 7 MPa and 500°C. One-fourth of the steam is extracted from the turbine at 600 kPa pressure for process heating. The remainder of the steam continues to expand and exhausts to the condenser at 10 kPa. The steam extracted for the process heater is condensed in the heater and mixed with the feedwater at 600 kPa. The mixture is pumped to the boller pressure of 7 MPa. 5 Boiler Pump II process Process heater 1-Ⓡ Determine the net power produced by the plant. The net power produced by the plant is [ KW. Turbine Condenser Pump I - (8)arrow_forwardAn Ideal cogeneration steam plant is to generate power and 9400 kJ/s of process heat. Steam enters the turbine from the boller at 7 MPa and 500°C. One-fourth of the steam is extracted from the turbine at 600 kPa pressure for process heating. The remainder of the steam continues to expand and exhausts to the condenser at 10 kPa. The steam extracted for the process heater is condensed in the heater and mixed with the feedwater at 600 kPa. The mixture is pumped to the boller pressure of 7 MPa. 5 Boiler Pump II process Process heater 1-Ⓡ Turbine Condenser Pump I - (8) Determine the mass flow rate of steam that must be supplied by the boller. Use steam tables. The mass flow rate of steam that must be supplied by the boller is kg/s.arrow_forward
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