Ecole des Mines de Nantes, GEPEA, UMR-CNRS 6144, Nantes, France.
J Hazard Mater. 2011 Dec 30;198:95-102. doi: 10.1016/j.jhazmat.2011.10.019. Epub 2011 Oct 8.
Organic vapors emitted from solvents used in chemical and pharmaceutical processes, or from hydrocarbon fuel storage stations at oil terminals, can be efficiently captured by adsorption onto activated carbon beds. To recover vapors after the adsorption step, two modes of regeneration were selected and could be possibly combined: thermal desorption by hot nitrogen flow and vacuum depressurization (VTSA). Because of ignition risks, the conditions in which the beds operate during the adsorption and regeneration steps need to be strictly controlled, as well as optimized to maintain good performances. In this work, the optimal conditions to be applied during the desorption step were determined from factorial experimental design (FED), and validated from the process simulation results. The regeneration performances were compared in terms of bed regeneration rate, concentration of recovered volatile organic compounds (VOC) and operating costs. As an example, this methodology was applied in case of dichloromethane. It has been shown that the combination of thermal and vacuum regeneration allows reaching 82% recovery of dichloromethane. Moreover, the vacuum desorption ended up in cooling the activated carbon bed from 93°C to 63°C and so that it significantly reduces the cooling time before starting a new cycle.
有机蒸气从化学和制药过程中使用的溶剂中排放，或者从石油码头的碳氢燃料储存站中排放，可以通过吸附到活性炭床上来有效地捕获。为了在吸附步骤后回收蒸气，可以选择两种再生模式并可能结合使用：热氮气流和减压（VTSA）热解吸。由于点火风险，需要严格控制床在吸附和再生步骤中运行的条件，并进行优化以保持良好的性能。在这项工作中，通过析因实验设计（FED）确定了在解吸步骤中要应用的最佳条件，并从过程模拟结果中进行了验证。从床再生速率、回收挥发性有机化合物（VOC）的浓度和运行成本方面比较了再生性能。例如，在二氯甲烷的情况下应用了这种方法。结果表明，热和真空再生的结合允许达到 82%的二氯甲烷回收率。此外，真空解吸最终将活性炭床从 93°C冷却至 63°C，从而大大减少了在开始新循环之前的冷却时间。
