摘要以含苯有机废气作为研究对象,建立了膜吸收-减压膜蒸馏的新型组合工艺。通过实验开展了膜吸收工艺在VOCS净化领域的研究,也对减压膜蒸馏工艺的再生性能进行了初步的研究。以n-甲酰吗啉(NFM)水溶液为吸收剂,疏水性多孔聚丙烯中空纤文膜组件为气、液膜接触器。通过实验研究得出了进口气流量、吸收剂流量、吸收剂浓度和进口气中苯的初始浓度等因素对去除率和总体积传质系数的影响。结果表明:膜吸收工艺具有较高的传质效率以及较高的稳定性和可操作性。在NFM体积分数为40%,进口气浓度为3.4~6.5mg•L-1,进口气流量为50~300ml•min-1条件下,C6H6的去除率可达到为50%~98%。在减压蒸馏过程中,通过实验研究得出了浓度、流速、温度等因素对吸收液再生性能的影响。结果表明:减压膜蒸馏技术对含苯NFM水溶液具有较好的再生效率,可达到80%以上。在NFM体积分数为40%,液速为30ml•min-1~70ml•min-1,浓度为0.18g•L-1~0.45g•L-1,温度在30℃条件下,膜通量在0.4×10-3~6.6×10-3mg•cm-2•min-1之间。9995
关键词:膜吸收;减压膜蒸馏;n-甲酰吗啉;;含苯废气
Abstract
In this paper, we established a new combined process, membrane-based gas performance of vacuum membrane distillation. This experiment focuse on a membrane based gas absorption process for the separation benzene (C6H6) from N2 and on vacuum membrane distillation (VMD) process for the absorbent regeneration. Using NFM aqueous solution as absorbent and PP as the membrane contactor. Effects of gas and liquid flow rate, absorbent concentration, benzene initial concentration in feed gas et al. on the removal efficiency and mass transfer coefficient were studied. The result shows that the characteristics of separation of C6H6/N2 by membrane contactor are of quicker mass transfer velocity and higher efficiency of separation.The removal efficiency achieves 50%~98%, when following conditions were used: volume rate of NFM,40%;consistency of feed gas, 3.6~6.5mg•L-1; flow rate of feed gas,50~300ml•min-1.In the cacuum membrane distillation process, effect of various factors, including concentration of absorbent , flowrate of absorbentand and temperature of absorbent were investigated.The result shows that VMD has higher efficiency of regeneration in separation of C6H6 from the aqueous solution od NFM, and the regeneration efficiency should be higher than 80%.The flux achieves 0.4~6.6×10-3mg•cm-2 •min-1, when following conditions were used: volume ratio of NFM, 40%; flowrate of absorbent, 30ml•min-1~70ml•min-1; concentration of absorbent, 0.18g•L-1~0.45g•L-1; temperature of absorbent,30℃.
Key words: membrane-based gas absorption , vacuum membrane distillation ,n-Formyl morpholine(NFM), waste gas containing benzene.
目录
摘要 I
Abstract II
1 绪论 1
1.1引言 1
1.2 VOC控制技术现状 1
1.3膜分离技术 1
1.4膜吸收技术 2
1.4.1膜吸收技术的研究方向 2
1.4.2系统工艺研究 2
1.4.3吸收液的筛选 3
1.4.4膜材料的筛选和膜组件的开发 3
1.5减压蒸馏技术 3
1.6 立题意义与研究内容 4
1.6.1立题意义 4
1.6.2研究内容 4
2实验与操作 5
2.1实验材料和试剂 5
2.1.1 膜组件 5
2.1.2吸收剂 5
2.1.3仪器 6
2.2 实验分析方法 6
2.2.1 气相中苯含量的测定 6 膜吸收处理含苯有机废气研究:http://www.751com.cn/cailiao/lunwen_8892.html