| Air adsorption has been extensively investigated for purification and treatment of organic gas contaminants, especially for recycling of volatile organic compounds (VOCs). Here we used an activated carbon adsorption system to investigate the adsorption performance of a kind of VOCs. ,The main objective of this study was to develop a model that could predict the adsorption performance curve of the VOC.The VOC selected was dichloromethane. The experiments were undertaken at atmospheric pressure (10 Pa) and three different temperature (15℃, 20℃ and 25℃). Other conditions of this experiment were as follows: The empty bed contact velocity was 0.34m/s, inlet concentration of dichloromethane was 28g/m3, the inner-diameter of bed column is 28mm, and the length of adsorption bed was 400mm. More details about the reactor system were described in the dissertation.Experimental data for dichloromethane was fit with model calculations for each impact studied. The modeling conditions and the physical properties of the fixed-bed and the adsorbent used during model verification were the same as the experimental conditions. All of the mathematic models were calculated by the computer program which compiled by Fortran.The results were concluded that:1. Breakthrough time of an adsorption system could be calculated by the breakthrough model (BT model). The relative error decreased as the reducing of the VOC concentrations.2. Based on the experiment results, mass transfer zone model (MTZ model) also could compute breakthrough time. We could adjust system parameter to make the calculating result fit the experiment result better.3. The model which integrated HERMIT-polynomial and ROSEN-equation (HPRE model) could calculate the outlet VOC concentrations. Thus the model not only could predict the breakthrough time, but also could predict the adsorption breakthrough curve.We also could conclude that HPRE model could fit other adsorption system through adjusting the correlative parameters.
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