改性沸石吸附柱去除氨氮的研究毕业论文

摘 要 氨氮是引起水体富营养化和环境污染的重要物质，采纳沸石去除水中氨氮是水污染控制领域的讨论热点之一。沸石是一种廉价的非金属矿物，具有独特的吸附和离子交换性能。天然沸石在改性过程中, 硅的质量分数显著减少，而钠的质量分数增多. 这样有利于 NH4+-N 的交换反应，因此改性沸石对氨氮的吸附 NH4+-N 的性能加强。本讨论首先对天然沸石进行了改性，确定了最佳的改性条件，并通过采纳动态法讨论改性沸石吸附柱去除微污染水源中氨氮的规律，包括改性沸石的粒径大小、入水流速、初始氨浓度等参数的影响，绘制穿透曲线。通过讨论，本文得出了以下结论：①沸石改性的最佳条件为：NaCl 溶液浓度 3mol/L，水浴温度 70～75℃，时间 3h；② NaCl 改性沸石的去除率明显高于未改性的。相比之下对氨氮的去除率增加了 8%；③沸石粒径越小，去除率越高，改性效果越好。沸石粒径在 0.5-1mm 是对氨氮的去除率最高；④入水流速越小，改性沸石对氨氮的去除率越高；⑤废水的初始浓度越低，改性沸石对氨氮的去除率越高。最高可到达 74%.关键词：改性沸石 氯化钠 氨氮 吸附 AbstractAmmonia-nitrogen(NH4+)is an important contaminant foreutrophication of water bodies and environmental pollution. Zeolite is a cheap non-metallic minerals,with unique adsorption and ion -exchange performance。 After natural zeolite is modified quality score of silicon significantly reduces ， And quality score of Sodiumincreases 。 It helps in ammonium-ion exchange ， so dsorption performance of modified zeolite strengthens。Atfirst the natural zeolite was modified by chemical approaches in the research,and choose thebest modifyingcondition of zeolite.Then study its treatment effect of low concentration NH4+in columnreactor and draw breakthrough curve, investigating such factors as pellet size, velocityof flow and nitial ammonia concentration etc. The main results of this research were as follows:ⅠUnder these circumstances:,c=3mol/l,T=70～75℃,the modification time3hours ， we can get the the right modified zeolite; Ⅱ removal efficiency of...