Consider a cogeneration power plant modified with regeneration. Steam enters the turbine at 9 MPa and 400°C and expands to a pressure of 1.6 MPa. At this pressure, 35 percent of the steam is extracted from the turbine, and the remainder expands to 10 kPa. Part of the extracted steam is used to heat the feedwater in an open feedwater heater. The rest of the extracted steam is used for process heating and leaves the process heater as a saturated liquid at 1.6 MPa. It is subsequently mixed with the feedwater leaving the feedwater heater, and the mixture is pumped to the boiler pressure. Assuming the turbines and the pumps to be isentropic, show the cycle on a T-s diagram with respect to saturation lines, and determine the mass flow rate of steam through the boiler for a net power output of 25 MW.
FIGURE P10–78
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- Steam is generated in the boiler of a cogeneration plant at 9 MPa and 450C at a steady rate of 5 kg/s. In normal operation, steam expands in a turbine to a pressure of 0.5 MPa and is then routed to the process heater, where it supplies the process heat. Steam leaves the process heater as a saturated liquid and is pumped to the boiler pressure. In this mode, no steam passes through the condenser, which operates at 20 kPa. Draw the schematic and T-S diagrams. Label the points by setting point 1 at the condenser outlet, point 2 at the 1st pump (after the condenser) outlet, point 3 at the process heater outlet, point 4 at the 2nd pump (after the process heater) outlet, point 5 at the boiler inlet, point 6 at the boiler outlet, point 7 at the process heater inlet, and point 8 at the condenser inlet. Use 2 decimal places for the enthalpy and other energies in solving and for the final answers. For the steam quality (x) and entropy (s), use 4 decimal places in solving. For the specific…arrow_forwardSteam is generated in the boiler of a cogeneration plant at 9 MPa and 450C at a steady rate of 5 kg/s. In normal operation, steam expands in a turbine to a pressure of 0.5 MPa and is then routed to the process heater, where it supplies the process heat. Steam leaves the process heater as a saturated liquid and is pumped to the boiler pressure. In this mode, no steam passes through the condenser, which operates at 20 kPa. Draw the schematic and T-S diagrams. Label the points by setting point 1 at the condenser outlet, point 2 at the 1st pump (after the condenser) outlet, point 3 at the process heater outlet, point 4 at the 2nd pump (after the process heater) outlet, point 5 at the boiler inlet, point 6 at the boiler outlet, point 7 at the process heater inlet, and point 8 at the condenser inlet. Use 2 decimal places for the enthalpy and other energies in solving and for the final answers. For the steam quality (x) and entropy (s), use 4 decimal places in solving. For the specific…arrow_forwardNOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part. Steam is generated in the boiler of a cogeneration plant at 600 psia and 650°F at a rate of 42 lbm/s. The plant is to produce power while meeting the process steam requirements for a certain industrial application. One-third of the steam leaving the boiler is throttled to a pressure of 120 psia and is routed to the process heater. The rest of the steam is expanded in an isentropic turbine to a pressure of 120 psia and is also routed to the process heater. Steam leaves the process heater at 240°F. Neglect the pump work. A. Determine the net power produced. Use steam tables. The net power produced is ______Btu/s. B. Determine the rate of process heat supply. Use steam tables. The rate of process heat supply is ________Btu/s. C.Determine the utilization factor of this plant. The utilization factor of this plant is .arrow_forward
- Steam is generated in the boiler of a cogeneration plant at 10 MPa and 450C at a steady rate of 5 kg/s. In normal operation, steam expands in a turbine to a pressure of0.5 MPa and is then routed to the process heater, where it supplies the process heat. Steam leaves the process heater as a saturated liquid and is pumped to the boiler pressure. In this mode, no steam passes through the condenser, which operates at 20 kPa. Determine the h4 at the pump (after the process heater) outlet in kJ/kg.arrow_forwardSteam is generated in the boiler of a cogeneration plant at 10 MPa and 450C at a steady rate of 5 kg/s. In normal operation, steam expands in a turbine to a pressure of0.5 MPa and is then routed to the process heater, where it supplies the process heat. Steam leaves the process heater as a saturated liquid and is pumped to the boiler pressure. In this mode, no steam passes through the condenser, which operates at 20 kPa. (a) Determine the power produced and the rate at which process heat is supplied in this mode. (b) Determine the power produced and the rate of process heat supplied if only 60 percent of the steam is routed to the process heater and the remainder is expanded to the condenser pressurearrow_forwardSteam is generated in the boiler of a cogeneration plant at 10 MPa and 450C at a steady rate of 5 kg/s. In normal operation, steam expands in a turbine to a pressure of0.5 MPa and is then routed to the process heater, where it supplies the process heat. Steam leaves the process heater as a saturated liquid and is pumped to the boiler pressure. In this mode, no steam passes through the condenser, which operates at 20 kPa. Determine the WP TOTAL in kJ/kg.arrow_forward
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