Mass transfer condenser capacity

Cp is the molar thermal capacity of the vapour L is the latent heat of volatilization and (Tg-Ts) is the temperature gradient between the gas phase and the condensed phase surface. Therefore, to estimate the volatilization of PbS by fitting the conditions for heat and mass transfer in the flame, (Sh/Nu)-(D/a)=l can be assiuned. 

A double-effect forward-feed evaporator is required to give a product which contains 50 per cent by mass of solids. Each effect has 10 m2 of heating surface and the heat transfer coefficients are 2.8 and 1.7 kW/m2 K in the first and second effects respectively. Dry and saturated steam is available at 375 kN/m2 and the condenser operates at 13.5 kN/m2. The concentrated solution exhibits a boiling-point rise of 3 deg K. What is the maximum permissible feed rate if the feed contains 10 per cent solids and is at 310 K The latent heat is 2330 kJ/kg and the specific heat capacity is 4.18 kJ/kg under all the above conditions. 

Where Q = Heat-Transfer Rate Fs = Steam Mass Flow AHs = Latent Heat of Vaporization F = Feed Rate Cp = Heat Capacity of Feed T0 = Steam Supply Temperature Pt = Steam Supply Pressure P2 = Steam Valve Outlet Pressure Ps = Condensing Pressure Tj = Inlet Temperature T2 = Outlet Temperature A Tm = Log Mean Temperature Difference Ts = Condensing Steam Temperature... 

A stirred tank shall be heated with condensing steam at pressure. It is filled with mass Ml of a liquid, which is at starting temperature Tlo- The heat transfer area is A. The tank wall thickness is. The tank wall has a heat conductivity of its heat capacity is insignificant (Fig. 4.3-10). 

Because only 0.03 wt% of the hydrocarbon entering the column condenses, the system can be treated as an inert gas dehumidification by use of Equation 6-23. For 70 IMTP packing, the value of the coefficient is 11.1 at atmospheric pressure, as shown in Table 6-3. Correcting this coefficient to the 0.3 power of the pressure, at 48 psia this coefficient will increase to 15.9. The base heat transfer coefficient at the bottom of the bed will be 1,396 Btu/h ft °F, while at the top of the bed it will be 899 Btu/h ft °F. The heat transfer coefficient must be adjusted for the effects of gas and liquid flow rates. This acjjustment is made by taking Uy as a function of the vapor capacity factor (Fg) to the 0.74 power and the liquid mass flow rate to the 0.40 power. The adjusted logarithmic average volumetric heat transfer co-efficient is 2,270 Btu/h ft °F. 

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