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compact heat exchanger uses condensing steam to heat liquid petroleum distillates in an oil refinery. The steam is under 3.302 bars of pressure, entering the heat exchanger at T1j =

410 K as saturated vapor. The steam condenses fully and exits the heat exchanger still at T1,0= 410 K, but as saturated liquid. A. Knowing that the mass flow rate of steam is 215 kg/hour, and looking up the latent heat of vaporization (H for steam at 3.302 bars, what is the rate of energy lost from the steam as it condenses (in W)? B. If the petroleum distillates have a mass flow rate of 3370 kg/h and a heat capacity of 2.39 kJ/kg-K, and enter the heat exchanger at T2i = 305 K, what is the exit temperature for the petroleum distillates (assuming they do not change phase)? (Note: an energy balance means that heat lost by the steam must enter the petroleum distillates – in other words, the internal energy lost by the steam = the internal energy gained by the distillates. We'll assume that there is no loss of heat to the environment). C. If the heat exchanger has an overall heat transfer coefficient of U = 114 W/m²-K, what surface area is required inside the heat exchanger to allow the heat to transfer from the steam to the petroleum distillates?(Note: The log mean temperature difference is defined as ATIM = {(T1j – T2,0)-(T1,0-T2,;)}/In{(T1j –T2,0)/(T1,0-T2,)}, where T1i is the inlet temperature of the steam, T1,0 is the outlet temperature of the steam, T2; isthe inlet temperature of the petroleum distillates, and T20 is the outlet temperature of the distillates.

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