Questions regarding distillation and heat exchange area
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I’m a newcomer working in the pesticide industry, and I’ve encountered the following problem recently: Given that the distillation rate of a distillation vessel is 150 kg/h, it is necessary to determine the heat exchange area of this vessel. I personally feel that there are quite a few parameters missing, but after all I’m a newcomer without any direction; I hope everyone can **give some advice – based on the parameters available now, is it possible to determine the heat exchange area? If not, what other parameters are needed?
Is there any inherent relationship between the distillation volume and the heat exchange area? Is it necessary to know things such as the composition of the medium being distilled, the heat source used, and so on?
1. First, calculate the heat required to heat the medium’s vapor to another temperature as follows: Q_medium = m*Cp1*(boiling temperature of the medium – t1) + m*r + m*Cp2*(t2 – boiling temperature of the medium). Here, m is the amount of material that evaporates, Cp1 is the specific heat capacity of the liquid phase, r is the latent heat of vaporization, Cp2 is the specific heat capacity of the gas phase, t1 is the inlet temperature, and t2 is the outlet temperature. 2. Secondly, the heat obtained by the evaporation vessel should be equal to the heat obtained by the medium; using this relationship, it can be seen that Q_vessel + Q_medium = Q_total. This value is related to parameters such as the heat source conditions (temperature, location, distribution), the heat transfer efficiency, and the heat transfer area. The required values have already been specified; to calculate Q_vessel, refer to heat exchanger design or boiler design principles. Additionally, with all other values constant, Q_vessel is generally proportional to the heat transfer area