【作者】 黎原小溪；

【导师】 王银叶；

【作者基本信息】 天津城市建设学院 ， 环境工程， 2008， 硕士

【摘要】 高氟地下水在我国分布广泛,已成为影响我国人民健康水平和社会经济发展的一个不可忽视的因素。本论文以有效去除低浓度（1～5mg/L）含氟地下水中过量氟为目的,应用纳米分子筛、硅藻土、改性分子筛、以改性分子筛和硅藻土为原料组成的复合材料,从静态实验、动态实验两方面开展了系列除氟研究。静态实验部分:1、单体材料除氟测试:实验结果表明,（z）XHX型纳米分子筛和硅藻土YN（Y）、CD10除氟效果较好。2、用盐酸对纳米分子筛进行了改性处理,对几种影响条件（盐酸浓度、固液比、煅烧温度、煅烧时间）进行了正交实验测试,正交实验结果显示,影响其除氟效果的主要因素影响力大小顺序为:盐酸浓度>固液比>煅烧温度>煅烧时间。最佳改性条件为: （z）XHX型纳米分子筛在500℃条件下,煅烧1h,再以3:50的固液比,用3.6%的HCl浸渍,烘干。改性分子筛除氟的最佳吸附时间范围是25～40min,材料最佳用量范围是0.25～0.4g/L。3、研究以改性分子筛和硅藻土为原料组成的复合材料。其最佳制备条件为:改性分子筛与YN（Y）,按比例1:1复配,方法采用球磨60min。该材料对氟的饱和吸附容量为18.38mg/g,吸附符合Langmuir吸附等温式。复合材料除氟的最佳吸附时间范围是20～50min,材料最佳用量范围是0.3～0.45g/L。适合处理含氟量在2～5mg/L的低浓度地下水。4、研究了改性分子筛、复合材料在最佳应用条件下,地下水中常见阴阳离子对F-去除的影响。对改性分子筛除氟效果影响大小顺序为SO₄^2->NO₃^->K⁺>Mg²⁺>Ca²⁺>Cl^->HCO₃^-。对复合材料除氟效果影响大小为SO₄^2-> NO₃^-> K⁺> Cl^-> Mg²⁺> HCO₃^-> Ca²⁺。5、利用XRD、IR等表征手段,对分子筛、改性分子筛及复合材料进行了表征。动态实验部分:动态连续处理实验以改性分子筛、复合材料为除氟剂,研究了沉降时间、原水浓度、材料用量和处理时间对除氟效果的影响。最佳连续处理实验条件为材料用量50g/200L,处理时间15min,沉降40min,出水浊度、氟离子浓度均达到国家饮用水标准。研究结果表明,复合材料除氟效率高且稳定、无毒无害、操作简便,比较适用于我国地下水氟浓度超标地区。更多还原

【Abstract】 The population being exposed to drinking water containing fluoride with a concentration higher than the current drinking water standard is believed to be over tens of million in China,and chronic arsenism and fluorosis pose serious social problems to our country. The objective of this study was to remove fluoride from low concentration fluoride ground-water. In this paper, a systematic study including static state and dynamic experiment.The series material including nanoparticle zeolite, diatomite, modified zeolite and composite that making up of modified zeolite and diatomite.Static Expermental:1.The defluoride test of monomer material: the results of experiment showed that na- nosized （z）XHX zeolite and YN（Y）,CD10 diatomite has better effect of defluoride.2.The nanosized zeolite was modified by hydrochloric acid.Study the influential factors of defluoride including: the concentration of hydrochloric acid, ratio of solid and liquidthe, time and temperature of modified process. The results of orthogonal test showed that the sequence of main factors that influenced F--containing groundwater treatment were concentration of hydrochloric acid> ratio of solid and liquidthe >the temperature of modified process>the time of modified process. When the temperature and time of calcined was 500℃and 1 hour, the ratio of zeolite and solution was 1:50 and the concentration of modified solution was 3.6% are the optimal condition of modified. The optinal adsorb condition was: the dosage was 0.25-0.4g/L,the time of adsorbed was 25-40 min.3. A compound metal was developed by modified zeolite and diatomite. The optimal conditions for preparation and fabrication of compound material are that the proportion of modified zeolite : diatomite YN（Y） was 1:1, ball milling time was 60min. The Q0（theoretical maximum adsorption capacity） of compound metal for fluoride was 18.38 mg/g, the adsorption isotherm of fluoride was correspond with the model of Langmuir. The optinal adsorb condition was: the dosage was 0.3-0.45g/L,the time of adsorbed was 20-50 min. The compound material was most suitable for water trement of low concentration fluoride ground-water.4.Study the competitive adsorption of some familiar ions in the groundwater for fluoride,when the applied condition of modified zeolite and compound metal was the optimal condition. The sequence that influenced the effect of fluoride removal by modified zeolite was SO₄^2->NO₃^->K⁺>Mg²⁺>Ca²⁺>Cl^->HCO₃^-. The sequence that influenced the effect of fluoride removal by compound metal was SO₄^2-> NO₃^-> K⁺> Cl^-> Mg²⁺> HCO₃^-> Ca²⁺.5. Nanoparticle zeolite, modified zeolite and composite were characterized by XRD and IR.Dynamic Experiment:In the continuous-flow column experiment, concentration of the raw water, the dosage of compound metal, contact-time were important factors. The optimal condition of dynamic experimentation was that the dosage was 50g/200L, the contact-time was 15min. The treated water meets the drinking water quality standards. The results of the study showed that compound metal was promising to replace those common adsorbents because of excellent fluoride removal ability, innocuity, cheap carriers. Compound metal had gotten successfully application the practice.更多还原