活性炭纤维吸附工业有机废气及其深度处理

发布时间：2018-10-26 19:30

【摘要】：继SO2、NOX之后挥发性有机化合物(VOCs)引起的环境问题又成为各国关注的焦点。活性炭纤维(ACF)作为第三代吸附剂拥有着优良的吸附性能,广泛应用于VOCs治理技术中。针对石化、包装、印刷、制药、皮革等行业产生大量的苯、甲苯、丁酮、乙酸乙酯等有机废气,本文使用活性炭纤维吸附法并进一步精馏提纯,分别对活性炭纤维吸附有机废气和后处理提纯进行了研究,主要内容如下：研究了活性炭纤维对单组份乙酸乙酯和混合组分的吸附特性,结果表明,活性炭纤维对乙酸乙酯和有机废气混合组分的吸附具有吸附平衡时间短、平衡吸附量大,在一定的时间内都能使净化气中的有机成分达到排放标准,但是混合组分会发生置换作用而使平衡吸附量会比单组份乙酸乙酯的平衡吸附量稍微大一些,同时不同进气浓度、流速等因素也会对平衡吸附量有着较大的影响。实验设备在运行一个月、三个月和一年时其吸附性能都能保持在80%以上,具有良好的循环使用性能。通过对活性炭纤维吸附机理的分析,以吸附等温方程Langmuir方程和Freundlich方程对实验数据进行拟合,发现Langmuir方程对等温吸附线的拟合最好,说明了活性炭纤维吸附主要是以单分子层吸附为主,同时也验证了活性炭纤维具有大量的微孔结构。采用精馏装置对活性炭纤维吸附解吸后产生的水相进行分离提纯,再使用3A分子筛除去回收的有机溶剂中的微量水分。实验结果表明,含水率为86%的有机水相经过精馏提纯后得到含水率为12%,再通过3A分子筛深度提纯后得到99.8%的有机溶剂。3A分子筛再生的中试实验中,选择吹冷风1h后,在220-C时,吹热风3h并保证热空气出口温度在150℃左右,降温时间3h,循环周期约在7h,再生的分子筛吸附效果良好,符合工业生产的要求。通过SEM图对3A分子筛结构进行分析,3A分子筛的吸附性能主要是由其内部的膜状物结构和立方体结构决定的。中试时3A分子筛吸附器运行一年后吸附性能仍良好,脱水后的有机溶剂含水率能够保持在3%以下,整套设备运行稳定。用CHEMCAD模拟乙酸乙酯和水的精馏过程,模拟结果如下,当进料组成为含水率为86%的乙酸乙酯混合液,当精馏塔进料塔板为22块浮阀式塔板时,能够得到含水率小于10%的乙酸乙酯混合液,理论上计算能够得到精馏工艺参数和条件来指导实验。结合活性炭纤维吸附和后处理提纯各自的优势,本文对有机废气吸附回收实例做了工程分析,结果表明在吸附周期内,活性炭纤维对有机废气的去除率达到98%以上,能够达到排放标准,具有很好的社会和经济效益。
[Abstract]:After SO2,NOX, the environmental problems caused by volatile organic compounds (VOCs) have become the focus of attention. As the third generation adsorbent, activated carbon fiber (ACF) has excellent adsorption performance and is widely used in VOCs treatment technology. In order to produce a large amount of organic waste gases such as benzene, toluene, butanone, ethyl acetate and so on in petrochemical, packaging, printing, pharmaceutical, leather and other industries, this paper uses activated carbon fiber adsorption method and further distillation purification. The adsorption and purification of organic waste gas by activated carbon fiber were studied respectively. The main contents are as follows: the adsorption characteristics of activated carbon fiber to ethyl acetate and mixed components were studied. The adsorption of the mixture of ethyl acetate and organic waste gas by activated carbon fiber has a short equilibrium time and a large amount of equilibrium adsorption. In a certain period of time, the organic components in the purified gas can reach the emission standard. However, the equilibrium adsorption capacity of the mixed group will be slightly larger than that of the monocomponent ethyl acetate due to the displacement effect. At the same time, different inlet air concentration, flow rate and other factors will also have a greater impact on the equilibrium adsorption capacity. The adsorption performance of the experimental equipment can be kept above 80% in one month, three months and one year, and it has good recycling performance. By analyzing the adsorption mechanism of activated carbon fiber, the experimental data were fitted with the adsorption isothermal equation Langmuir equation and Freundlich equation. It was found that the Langmuir equation fitted the isothermal adsorption line best. The results show that the adsorption of activated carbon fiber is mainly monolayer adsorption, and it is also proved that the activated carbon fiber has a large number of micropore structures. The aqueous phase produced by adsorption and desorption of activated carbon fiber (ACF) was separated and purified by rectifying device and triple-A molecular sieve was used to remove trace water from the recovered organic solvent. The experimental results show that the organic water phase with 86% moisture content is purified by distillation and the moisture content is 12%, and 99.8% organic solvent is obtained after deep purification of 3A molecular sieve. After 1 h of cold air blowing and 220-C, the hot air is blown for 3 h, and the outlet temperature of hot air is about 150 鈩，

本文编号：2296731