In this case, will the top circulation draw out the water?
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Top temperature: 124, top circulation extraction temperature: 143, water dosage in reaction: 74 tons, fractionation pressure: 0.1978 MPa, cold reflux: 50 tons
The evacuation of the top circulation water is closely related to the temperature of the top circulation return tower; it is necessary to prevent the temperature of this tower from dropping too low, as this could lead to the evacuation of the top circulation water. Generally, the temperature of the top circulation return tower is maintained between 75 and 85°C.
The data is incomplete; normally, no water should be present. This post was last edited by “Ignorance is no crime” on January 2, 2008, at 13:35.]
Please specify what data is required!
Whether there is water in the top layer depends on the dew point temperature of water vapor at the vapor pressure at the extraction location; if the temperature of that layer is lower than this temperature, then there is water present, whereas if it is higher, then no water is present. To calculate the dew point, it is necessary to adjust the pressure and molar composition to compute the partial pressures/It should be clarified that this is not the case
Yes, water can be carried along. Our device has experienced situations where there was a circulation of water at the top! The parameters are more or less as you said! I don’t know the specific reason either!
The data should also include the top circulation flow rate; moreover, your cold return flow rate is too high, which results in a high load on the tower top cooler and a large pressure drop at the top of the distillation tower, pushing the water downward.
Under normal circumstances, as long as the return temperature of the top circulation is not too low, such problems will not occur.
What is the processing capacity, and is the cold reflux too high?/
The pressure at the top of the tower is too high; it is necessary to calculate the dew point temperature of the water vapor at this pressure, to determine whether the extraction temperature is higher than this value. If it is higher, then no water will be carried along during evacuation; otherwise, it is required to adjust the reflux from the top of the tower or the cold reflux stream in order to raise the extraction temperature. It seems your extraction temperature is too low.
The top pressure of the tower does not reflect the state of water vapor inside the tower; the vapor partial pressure within the tower should be calculated instead. Too low a return tower temperature can also easily lead to water entrainment in the top circulation. Excessive cold reflux will cause the liquid phase temperature on the trays in the top section of the tower to be too low, allowing steam to condense easily.