5.1.3 The feed water to a boiler enters an economizer at 32°C and leaves at 120°C, being fed into the boiler at this temperature. The steam leaves the boiler 0.95 dry at 2.0MPA and passes through a super- heater where its temperature is raised to 250°C without change in pressure. The steam output is 8.2kg/kg of coal burned and the calorific value of the coal is 28MJ/kg. Take the specific heat capacity of superheated steam = 2.093kJ/kgK and that for the feed water = 4.18kJ/kgK. Determine the energy received per kilogram of water and steam in the following components and express your answers as percentages of the energy supplied by the coal: %3D 5.1.3.1 the economizer

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An electric water heater is fed with an input stream of 15.0 kg/min of water at 17.5°C. Hot water is then provided as two different output streams, one at 43.0°C and the other at 60.0°C. The volume of the water in the tank remains constant and the mass flowrate of the outlet stream at 43.0°C is 10.5 kg/min. Perform the following activities, i. Draw a detailed flowchart for this process with all given information. ii. Calculate the power, Q (in kW) that the electric heater must provide in order to keep the temperatures of the outlet streams at 43.0°C and at 60.0°C, respectively. You must write the mass and energy balances and show your calculation. Given: AH + AĖK + AĖ, = Q – W, where AH stands for the difference in enthalpy; ΔΗ- ΣΗoal -ΣΗit ial s As AH = H; – H,ref = mC,(T; – Tref), if the reference temperature Tref is selected as 0°C, the absolute enthalpy is given by AH¡ = H¡ = mC,T- %3D - %3D k] The specific heat of water is constant and is 4.182 within the range of kgºC temperature…