Material balance means that the amount of material entering the alcohol recovery tower per unit time should be equal to the sum of the amounts of materials leaving the tower. The material balance reflects the production capacity of the tower, which is mainly adjusted by the amount of feed and the amount of discharge at the top and bottom of the tower. During operation, the change of material balance is specifically reflected in the liquid level at the bottom of the column. When the operation of the column does not meet the overall material balance, it can be reflected from the change in the pressure difference of the column. For example, if there is more input and less output, the pressure difference of the tower will rise. For a fixed alcohol recovery tower , the tower pressure difference should be within a specific range, the tower pressure difference is too large, the speed of the rising vapor in the tower is too large, the mist entrainment is serious, and even liquid flooding occurs and the normal operation is destroyed; If the pressure difference of the tower is too small, the speed of the rising vapor in the tower is too small, the mass transfer effect of the gas-liquid two-phase on the tower plate is reduced, and even liquid leakage occurs, which greatly reduces the efficiency of the tower plate. If the material balance is not well mastered, the operation of the entire tower will be in a chaotic state. Mastering the material balance is a key to the operation of the tower. If the normal material balance is destroyed, it will affect the other two balances, that is, the gas-liquid phase balance cannot achieve the expected effect, and the heat balance is also destroyed and needs to be readjusted.
The gas-liquid phase balance mainly reflects the quality and loss of the product. It is met by adjusting the operating conditions (temperature, pressure) of the alcohol recovery tower and the gas-liquid contact on the tray. Only when the temperature and pressure are fixed, can there be a definite gas-liquid phase equilibrium composition. When the temperature and pressure change, the composition determined by the gas-liquid phase equilibrium will change, and the quality and loss of the product will change accordingly. The gas-liquid phase balance is closely related to the material balance. If the material balance is well mastered, the rising vapor velocity in the tower is appropriate, and the gas-liquid contact is good, the heat and mass transfer efficiency will be high, and the tray efficiency will also be high. Of course, the temperature and pressure will also change with the change of the material balance.
https://www.syhgzben.com/
