氢氧化铁改性滤料去除水中硫酸盐的研究

发布时间：2018-05-29 18:01

  本文选题：氢氧化铁 + 改性滤料　； 参考：《哈尔滨理工大学》2017年硕士论文

【摘要】：目前去除水中硫酸盐的方法有:化学沉淀法(钡法、钙法)、物理法(冷冻法、膜法)、离子交换法、生物法、吸附法等。近年来,研究者们一直在关注吸附法去除水中的硫酸盐,常采用的吸附材料有针铁矿、蒙脱石等多孔材料。本研究采用氢氧化铁对石英砂滤料进行改性,考察改性滤料层对水中硫酸盐的去除效果。实验将新生态氢氧化铁附着在7cm厚的滤床中,通过滤床过滤含有硫酸盐的原水,考察滤料种类、滤料粒径、硫酸盐浓度、过滤速度、p H值等对改性滤料去除硫酸盐的影响。实验结果表明:氢氧化铁改性滤料表层存在Fe(OH)_3溶胶体系,胶状的水合氧化铁(Ⅲ)有较强的吸附性,当以较低的滤速注入含硫酸根的原水时,硫酸根可与Fe(OH)_3溶胶表面吸附的高价铁离子发生聚沉(尤其是在酸性环境下),形成聚沉物,并被滤料截留,从而使硫酸根得到去除。研究发现,采用新生态氢氧化铁改性过的石英砂(粒径为1.18-1.4mm)滤料对硫酸根的去除效果要优于新生态氢氧化铁改性过的柱状活性炭滤料(粒径为1.5mm),二者的平均去除率分别为71.58%和62%;对于粒径为1.18-1.4mm的改性石英砂,在其它条件一定时,初始硫酸根浓度越小,硫酸根的去除率越高;通过改变石英砂的粒径范围发现,粒径为0.42-0.71mm时,硫酸根的去除效果最佳,平均去除率达到了80%;在不同的粒径范围内,用新生态氢氧化铁改性过的石英砂滤料对硫酸根的去除效果要优于用预制备氢氧化铁改性过的石英砂滤料,二者的去除率范围分别为69.76%-79.87%和59.57%-72.12%;尽管硫酸根的去除率与Fe(OH)3在石英砂滤料上的涂装量成正比,但由此带来的变化量不大,当涂装量从1000 mg·L~(-1)变化到2000 mg·L~(-1)时,硫酸根的去除率变化量不超过5%;过滤过程因素对新生态氢氧化铁改性滤料去除硫酸根的效率有影响,随着原水水温的升高,硫酸根的去除率总体呈上升趋势,在原水pH值为3-10时,随着p H值的增大,硫酸根去除率呈现减小趋势,p H值对吸附容量也有影响,原水pH=3-4时,吸附容量最大,为23mg·g~(-1)。
[Abstract]:At present, the methods of removing sulfate in water include chemical precipitation method (barium method, calcium method), physical method (freezing method, membrane method, ion exchange method, biological method, adsorption method and so on). In recent years, researchers have been paying attention to the adsorption of sulfate in water. The adsorption materials are goethite, montmorillonite and other porous materials. In this study, ferric hydroxide was used to modify quartz sand filter material, and the removal effect of sulfate in water by modified filter media layer was investigated. The new ecological ferric hydroxide was attached to the 7cm thick filter bed. The raw water containing sulfate was filtered by the filter bed. The effects of filter media type, filter media particle size, sulfate concentration, filtration speed and pH value on the removal of sulfate from the modified filter media were investigated. The experimental results show that there is Fe(OH)_3 sol system in the surface layer of ferric hydroxide modified filter media, and the colloidal hydrated ferric oxide (鈪，

本文编号：1951872