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随着经济的迅猛发展以及城市化进程的加快,建筑垃圾数量大增。建筑垃圾 的随意堆放,不仅破坏生态环境,而且也是一种资源浪费。目前,国内外已开始 重视对建筑垃圾的资源化利用。砖是建筑行业的三大基本材料之一。本文以建筑 垃圾中普遍存在的建筑废砖为原材料制得吸附剂,考察了其对磷酸盐、氨氮、氟 化物及亚甲基蓝的吸附行为,探讨了各吸附条件对吸附效果的影响,并进一步研 究了吸附动力学和吸附热力学,旨在深入研究确定建筑废砖对水中污染物的吸附 机理,开发一种高效、易得、经济的吸附剂,以便于防止和控制日益严重的水污 染现象。本试验研究结果如下, (1)建筑废砖颗粒吸附水中初始浓度为 100 mg/L 磷酸盐的动力学结果表明, 吸附平衡时间为 216 h,20°C 时吸附量为 2.10 mg/g,4°C 时为 1.11 mg/g。其吸附动 力学可较好地符合伪二级吸附动力学模型;建筑废砖颗粒对磷酸盐的吸附符合 Langmuir 吸附等温模型。 (2) 20℃条件下吸附初始浓度为 100 mg/L 磷酸盐影响因素试验表明,本试验 的最佳吸附条件为,振荡速度为 150rpm,废水 pH 值在 2 左右,此时去除率达 83.90%。在四种无机阴离子共存的污水体系中, 只有 HCO 3 - 对建筑废砖吸附除磷 有较大的抑制作用,其余阴离子(Cl - 、NO 3 - 、SO 4 2- )均无显著的影响,说明建筑 废砖能够选择性地吸附水体中的磷酸盐污染物, 适宜作为除磷吸附剂。 (3) 在 20℃和 4℃条件下,建筑废砖颗粒对初始浓度为 10mg/L 的氨氮平衡吸 附量分别为 0.07mg/g 和 0.05mg/g,去除率分别为 27.0%和 21.9%,去除率较低,。 (4) 对水中氟化物的振荡吸附试验和不同初始浓度条件下吸附行为的研究的 结果表明,本试验建筑废砖颗粒对氟化物的去除基本无效果,不适于作为除氟吸 附材料。 (5)建筑废砖颗粒对初始浓度为 10mg/L 亚甲基蓝的吸附平衡时间为 72h,去西安建筑科技大学硕士学位报告 除率达 98.2%。振荡速度、初始 pH 值以及温度都对吸附无明显影响。动力学分 析结果表明,建筑废砖颗粒对亚甲基蓝的吸附符合伪二级动力学方程;等温线拟 合结果表明,对亚甲基蓝的吸附符合 Langmuir 等温模型。通过不同浓度吸附效果 的对比,发现建筑废砖只适合浓度为 200 mg/L 以下含亚甲基蓝废水的处理。 (6)不同产地建筑废砖对水中污染如氨氮和磷的去除效率有很大差异性,本 研究的结果表明西安周边的以黄土为原料的废砖对这些污染物的吸附容量明显小 于福建等地以红壤为原料的废砖,因此,在将建筑废砖用于水处理,如作为人工 湿地填料强化其对营养盐的去除时,应充分考虑这种地域差异性。 关 键 词,建筑废砖;磷酸盐;氨氮;氟化物;亚甲基蓝 报告类型,基础研究西安建筑科技大学硕士学位报告 Feasibility Study on the Removal of Pollutants in Wastewater Using Construction Waste Brick as an Adsorbent Specialty:Municipal Engineering Author: Zhai Xuna Advisor: Prof. Ren Yongxiang Abstract With the rapid development of economy and acceleration of urbanization, the number of construction waste increased dramatically. Arbitrarily stacking of construction waste will not only the ecological environment, but also cause the waste of resources. Currently, domestic and overseas have begun to pay great attention to the resource utilization of construction waste. Brick is one of the three basic building materials.In order to develop an efficient, readily available and economic adsorbent for pollution removal to prevent and control the increasingly serious water pollution, this paper investigated the adsorption behavior of phosphate, ammonia nitrogen, methylene blue and fluoride to construction waste brick in aqueous solutions, and analyzed the absorption characteristics of the four pollutants. The results are as follows: (1) The results of dynamic analysis on the adsorption of phosphate to construction waste brick revealed that the adsorption equilibrium might take 216 hours to reach, and the adsorption capacity could be 2.10 mg/g at 20°C and 1.10 mg/g at 4 °C, respectively. Characteristics of adsorption could be best described by the pseudo-second-order model, and the behavior was fitted well with Langmuir isotherm. (2) The result of effect factors in 20°C indicated that: when oscillation speed was 150 rpm, and the wastewater pH was around 2, the experiment could reach the maximum removal rate of 83.90%. In the water system of the coexistence of four inorganic anions, they all had no significant impact on the phosphorus removal, except HCO 3 - , it had greater inhibition on the adsorption of phosphorus onto construction waste brick. So construction waste brick in this study could be selective for adsorption of phosphate in water bodies, and appropriate for phosphorus removal adsorbent.西安建筑科技大学硕士学位报告 (3) In the conditions of 20 °C and 4 °C, the construction waste brick particle had the adsorption capacity of 0.07mg/g and 0.05 mg/g, and the removal efficiencies were 27.0% and 21.9% respectively for the ammonia nitrogen concentration of 10mg/L. It showed that construction waste brick in this study was not a kind of excellent performance of ammonia nitrogen adsorbent because of its low removal rate. (4) The results of the adsorption behavior of the different oscillation speed and initial concentrations of fluoride in the water showed that, construction waste brick almost had no effect on the removal of fluoride. Therefore, it was not suitable for fluoride removal. (5) Construction waste brick had the adsorption equilibrium time of 72 h, and the removal rate of 98.2%, when the methylene blue of 10mg/L. Oscillation speed, initial pH and temperature had no significant effect on the adsorption. Characteristics of adsorption could be best described by the pseudo-second-order model, and the behavior was fitted well with Langmuir isotherm. By the comparison of the adsorption effect in different concentrations, it demonstrated that construction waste brick was only suitable for concentrations of 200mg/L below of methylene blue wastewater treatment. (6) Different origin of construction waste brick had very different removal efficiency of pollutants, such as ammonia nitrogen and phosphate. The results of this study indicated that, the adsorption capacity of the pollutants on waste brick in Xi’an was significantly smaller than in Fujian. Because waste brick in Xi’an was made by loess, while waste brick in Fujian was made by red soil. Therefore when the construction waste brick was used for wastewater treatment, such as strengthen the nutrient removal in constructed wetlands, should fully take into account the regional difference. Key words: construction waste brick; phosphate; ammonia nitrogen; fluoride; methylene blue. Paper type: Fundamental Research西安建筑科技大学硕士学位报告 I 目 录 1 绪论 ............................................................................................................................ 1 1.1 营养盐类物质..................................................................................................... 1 1.1.1 水体富营养化 ............................................................................................. 1 1.1.2 污水除氮方法 ............................................................................................. 2 1.1.3 吸附剂的类型及特点 ................................................................................. 3 1.1.4 污水除磷方法 ............................................................................................. 4 1.1.5 除磷吸附剂的种类及特点 ......................................................................... 5 1.2 氟......................................................................................................................... 6 1.2.1 氟的性质 ..................................................................................................... 6 1.2.2 氟的分布、来源及对人体的危害 ............................................................. 6 1.2.3 饮用水中允许含氟量 ................................................................................. 8 1.2.4 国内外除氟研究现状及进展 ..................................................................... 8 1.3 亚甲基蓝........................................................................................................... 11 1.3.1 染料废水的来源及性质 ........................................................................... 11 1.3.2 亚甲基蓝的危害 ....................................................................................... 11 1.3.3 亚甲基蓝废水的处理方法 .............................