低浓度甲醛水溶液的气液平衡体系研究

Research on the vapor-liquid equilibrium system of formaldehyde aqueous solution with low concentration

利用气液平衡测定装置,在加压条件下,首次测定了低浓度(质量浓度为1%以下)甲醛水溶液的气液平衡参数.根据实验数据计算出的低浓度甲醛水溶液的相对挥发度的平均值与相同条件下较高浓度的甲醛水溶液的相对挥发度的理论值很接近.通过饱和蒸汽压法及Wilson模型对低浓度下甲醛-水二元体系的气液平衡参数进行了理论计算,并将计算值与实验值进行了比较,验证了实验数据的真实可靠性.获得的低浓度下甲醛水溶液的气液平衡参数可为回收甲醛采用的加压精馏塔的工业设计提供理论依据和参考.

By the vapor-liquid equilibrium measuring device,the vapor-liquid equilibrium parameters of formaldehyde aqueous solution with low weight concentration of below 1% was measured under high pressures for the first time.The average value of relative volatility for the formaldehyde solution with low concentration,which was calculated by the experimental data,is very close to the reported one for formaldehyde aqueous solution with higher concentrations.The vapor-liquid equilibrium parameter of formaldehyde solution with low concentration was theoretically calculated by the saturated vapor pressure method and Wilson model,and compared with the experimental data.The little relative deviation between them has verified the authenticity and reliability of the experimental data.The vapor-liquid equilibrium parameters obtained in this paper can offer theoretical basis and reference for the design of the high pressure distillation,and the recovery of formaldehyde from the waste water can be achieved successfully by high pressure distillation.Therefore,the vapor-liquid equilibrium parameters obtained in this paper has a certain Industrial significance.