直链饱和一元醇膜吸收法处理高浓度甲醛废气  

Treatment of high concentration formaldehyde using straight-chain saturated monohydric alcohols with membrane contactors

作　　者：万新水 朱振中 王志良[2] 吴海星 孙宏辉 

机构地区：[1]江南大学化学与材料工程学院,无锡214036 [2]江苏省环境科学研究院,南京210036

出　　处：《膜科学与技术》2010年第5期47-51,共5页Membrane Science and Technology

基　　金：江苏省科技支撑计划-社会发展基金项目(BE2008685);江苏省环境工程重点实验室开放课题(KF2007001)

摘　　要：采用中空纤维膜接触器,直链饱和一元醇为吸收剂处理高浓度甲醛废气.通过比较一系列直链饱和一元醇（C=2-5）对甲醛去除效率的影响,发现甲醛的去除率虽有一定差异,但并不显著.综合考虑各因素,选择正戊醇为吸收剂较为适宜.研究了甲醛进气浓度、吸收剂温度、甲醛进气流量及吸收剂流量对甲醛去除率和传质系数的影响.结果表明,当甲醛进气浓度为1 228.8 mg/m^3,吸收剂温度为25℃,进气流量为6.7×10^-6m^3/s,吸收剂流量为6.9×10^-7m^3/s时,甲醛出气浓度为1.73 mg/m^3,去除率为99.85%,传质系数为8.71×10^-5m/s.进一步研究表明,吸收反应产物（缩醛）可通过精馏或调节酸度的方法与吸收剂（正戊醇）分离,回收率可达99.5%,分离回收的正戊醇可继续循环使用.A new technique for treatment of high concentration formaldehyde with straight-chain saturated monohydric alcohols by hollow fiber membrane contactor was developed.Firstly,some straight-chain saturated monohydric alcohols（C=2～5） were used as absorbents to compare their efficiency to remove formaldehyde under the same conditions.It discovers that their removal efficiency to formaldehyde have little difference,it is feasible to use n-pentanol as absorbent after considering various kinds of influencing factors.Secondly,some important factors,such as the concentration of the feed gas,temperature of the absorbent,inlet flux of the feed gas and the absorbent flux were thoroughly studied when n-pentanol was used as absorbent.Experimental results show that under proper operation conditions,the inlet concentration of formaldehyde is 1 228.8 mg/m3,the absorbent temperature is 25 ℃,the inlet flux of feed gas is 6.7×10-6m3/s and the absorbent flux is 6.9×10-7m3/s,the outlet concentration of formaldehyde is 1.73 mg/m3,the removal rate of formaldehyde is 99.85% and the overall mass transfer coefficient is 8.71×10-5m/s.Finally,the feasibility of resource utilization of formaldehyde gas was preliminary investigated.It is found that the absorption product can be easily separated through distillation or adjusting the pH of absorbent,and the recovery of formaldehyde can be reached 99.5%.Moreover,the absorbent,n-pentanol,can be recycled.

关 键 词：中空纤维膜接触器 膜吸收 甲醛废气 直链饱和一元醇 

分 类 号：X701[环境科学与工程—环境工程]