You, a process design engineer, are tasked to build a powerplant that utilizes 1.5 metric tons of municipalsolid wastes (MSW) per hour. In an industrial boiler, MSW is burned to heat and pressurize 1 kg/s ofpreheated water to high-pressure steam (44 atm, 450 °C).The high-pressure steam, moving at a linear velocity of 70 m/s, is then used to drive a high-pressureturbine. In a heat exchanger, the used steam from the outlet of high-P turbine at an intermediate pressure(10 atm, 250 °C) is used to preheat the water that will be fed to the boiler. This water is pumped from anunderground reservoir at a low velocity (1 atm, 25 °C).After preheating the water, the intermediate-pressure steam leaving the heat exchanger is then used todrive a low-pressure turbine. Lastly, the steam from outlet of the low-P turbine leaves at a velocity of 10m/s (at 1 atm and 100 °C) via an exhaust 10 m above the pump inlet.The industrial boiler is insulated, but due to the high temperatures and the nature of the process, there areinevitably heat losses. As such, 25% of the heat from the burning of MSW is lost from the boiler.Your assistant has conveniently looked up the following values from the handbook:• Q25 °C, 1 atm: H = 104.93 kJ/kg, phase: liquid@100 °C, 1 atm: H = 2675.53 kJ/kg, phase: steam@250 °C, 10 atm: H = 2942.73 kJ/kg, phase: steam@450 °C, 44 atm: H = 3324.63 kJ/kg. phase: steama) If 1 kg of MSW releases 12000 kJ of heat, what is the net work output of the powerplant?b) If the shaft work in the pump is negligible, what is the work output in the low-P turbine? Hint: performanother energy balance

Net Work Output = h2 - h1 = 2675.53 - 104.53 = 2570.6 kJ/kg Work Delivered = h4 - h3 = 3324.63 -…

a) If 1 kg of MSW releases 12000 kJ of heat, what is the net work output of the powerplant? b) If the shaft work in the pump is negligible, what is the work output in the low-P turbine? Hint: perform another energy balance

a) If 1 kg of MSW releases 12000 kJ of heat, what is the net work output of the powerplant? b) If the shaft work in the pump is negligible, what is the work output in the low-P turbine? Hint: perform another energy balance

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.4DP

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