Heat distribution in the distillation tower

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During operation, the economic efficiency of the distillation tower should be carefully considered, while ensuring product quality. At this point, we generally focus on the heat extraction distribution across various recirculations; a good distribution leads to better energy-saving effects. For example, by minimizing the amount of heat extracted from the top or upper sections of the recirculation flow, it is possible to reduce the amount of low-temperature heat that is difficult to recover ； Increasing the heat absorption from the lower return flow allows for an increase in the heat source at high temperatures, facilitating heat exchange and recovery. For example, in atmospheric pressure columns, the commonly adopted heat extraction ratio is top: middle 1: middle 2 = 3:4:3 or 3:3:4. Of course, to reduce low-temperature heat sources, many towers now use a top-circulation reflux method. Therefore, in work it is often necessary to calculate the heat absorption distribution; determining the heat balance for the entire tower involves a large amount of data, making the calculations relatively complex. We should find a relative calculation method for daily production control. The method I use now is to simply calculate the heat from several reflux streams using the enthalpy difference; by summing these values, an approximate total heat uptake for the entire column is obtained, after which the proportion of heat taken up by each reflux stream can be determined. Discussion is welcome.