自然循环蒸发器沸腾段高度计算

Calculation of Boiling Section Height of Natural Circulation Evaporator

自然循环蒸发器运行过程中易发生结垢堵塞,其主要原因是溶液在换热管中产生沸腾形成结晶垢,要避免换热管内沸腾现象发生,需保持换热管上方有一定液位高度,溶液在液柱静压作用下溶液沸点升高,从而抑制溶液沸腾。为计算出换热管外沸腾段高度,利用传热基本方程及热力学方程,从理论上推导出蒸发器沸腾段高度计算公式,并根据生产数据计算硝酸钠蒸发器沸腾段高度。沸腾段高度计算公式为蒸发器合理设计及操作提供了依据。

The fouling blockage is likely to occur during the operation of natural circulation evaporator.The main reason is that the solution is boiled in heat exchange tube to form crystal scale.In order to avoid the boiling phenomenon in heat exchange tube,it is necessary to maintain a certain liquid level above the heat exchange tube.The boiling point of the solution increases under the static pressure of liquid column,thereby inhibiting the boiling of the solution.In order to calculate the height of boiling section outside the heat exchange tube,the basic equation of heat transfer and the thermodynamic equation are used to theoretically derive the formula for calculating the boiling height of evaporator,and calculate the boiling section height of sodium nitrate evaporator according to the production data.The calculation formula of boiling section height provides a basis for the rational design and evaporator operation.