冷凝和吸附集成技术回收有机废气

有机废气治理的难度在于石化、石油、化工等领域的工艺不同,导致排放的废气组分及浓度相差很大。根据有机废气的特点,选择合适的工艺进行有效治理并实现资源回收是非常必要的。目前,冷凝和吸附集成工艺回收有机废气成为人们的研究重点。冷凝法回收有机废气应用于高浓度场合,尤其适合应用在集成工艺的前端。吸附法回收技术更适合于低浓度油气吸附,作为集成技术的后端处理。有机废气冷凝和吸附集成技术,既发挥冷凝法在冷凝高浓度油气方面高效的优势,以及吸附法在吸附低浓度油气时可以将油气浓度控制在很低范围的优势,同时又可避免单纯冷凝技术由于低温冷凝而引起的成本及操作费用剧增,以及吸附法由于吸附高浓度油气而产生的安全隐患。通过对冷凝和吸附段的工艺及结构参数进行优化,并选择合适的制冷剂及吸附剂,以期最终达到回收率、设备投资、运行能耗及安全性等综合技术经济指标的最优化。

Integrated technology of condensation and adsorption for volatile organic compounds recovery

There are some problems in controlling the emission of volatile organic compounds(VOCs),for the diversity of components and concentrations of different VOCs from the different industries of petroleum or petrochemical.So,it is very necessary to choose a proper technology to control the VOCs emissions and recover the valuable resources from the exhaust gas of VOCs-air,according to the different concentrations and components of VOCs.Currently,the integrated separation technology of condensation and adsorption is a hot research topic for the VOCs recovery.The condensation separation method is high efficient in recovering the high concentration VOCs,but the costs of investment and operation are very high for keeping the outlet VOCs concentration low due to the required low condensation temperature.Thus,the method is especially suitable to be chosen as the front process.The adsorption separation method has an obvious advantage in keeping the outlet VOCs concentration very low in recovering the low concentration VOCs,but it may lead to the risk of fire accidents due to the high heat effect in recovering the high concentration VOCs.Accordingly,the method is especially suitable for the rear process.Some key issues were analyzed and discussed,such as the choice of the proper refrigerant and adsorbent for recovering different VOCs,and the optimization of the process and structure of the integrated separation system so as to achieve higher recovery efficiency,lower costs of the investment and operation,and safe operation.