陶粒改性及其对氮磷的吸附效果研究毕业论文
2022-01-31 21:43:38
论文总字数:21662字
摘 要
人工湿地技术作为一种高效低耗的自然处理工艺,以其优良的特性,已经在世界范围内的污水处理领域得到广泛应用。但人工湿地仍然存在其自身的缺点,提高填料材料的吸附能力是增强人工湿地系统对氮磷去除的关键。
本课题拟将市场上售卖的商品陶粒进行表面改性,改善陶粒的表面特性,增加其吸附能力。
- 以葡萄糖为炭源采用水热法制备了炭化改性。采用SEM、XRD、BRT、FTIR等手段对覆碳陶粒进行表征发现,陶粒炭化改性后陶粒表面呈黑色,表面存在大量碳球;比表面积增大7.43倍,新增Si-O-Si键和C-H键;对氮磷的吸附总量提高了两倍以上。
(2)在炭化改性的基础上分别用水热法和共沉淀法对陶粒进一步进行磁/碳改性。对水热法改性陶粒采用SEM、XRD、BET、FTIR等手段对炭/磁化后的陶粒进行表征发现,陶粒磁/碳改性后表面呈黑色,比表面积增大4.57倍,其表面除水热法覆盖的炭球之外引入了一部分的磁性氧化铁;磁化改性陶粒对氮磷的吸附能力大于原陶粒,略小于炭化改性陶粒。
(3)在炭化改性的基础上采用共沉淀法对陶粒进行磁化改性,进行总量吸附实验后发现改性后陶粒虽比原陶粒吸附总量增大,但是略小于单独炭化的陶粒。
关键词:陶粒;表面改性;水热法;共沉淀法
ABSTRACT
As a high-efficiency and low-loss natural treatment process, the constructed wetland technology has been widely used in the field of sewage treatment worldwide due to its excellent characteristics. However, constructed wetlands still have their own shortcomings. Increasing the adsorption capacity of filler materials is the key to enhancing the removal of nitrogen and phosphorus from constructed wetland systems.
This project intends to surface-modify the commercial ceramsite sold on the market, improve the surface properties of ceramsite and increase its adsorption capacity.
(1) Carbonization modification was prepared by hydrothermal method using glucose as a carbon source. The SEM, XRD, BRT, FTIR and other methods were used to characterize the carbon-coated ceramsite. It was found that the surface of the ceramsite was black after carbonization, and there were a lot of carbon spheres on the surface; the specific surface area increased by 7.43 times, and Si-O- was newly added. Si bond and CH bond; the total amount of nitrogen and phosphorus absorption more than doubled.
(2) Based on the carbonization modification, the ceramic particles were further subjected to magnetic/carbon modification by hydrothermal method and coprecipitation method, respectively. The ceramsite was characterized by SEM, XRD, BET, FTIR and other methods on the hydrothermal modified ceramsite. The results showed that the magnetic/carbon modified ceramic surface was black and the specific surface area was increased by 4.57 times. A part of the magnetic iron oxide was introduced on the surface except for the carbon spheres covered by the hydrothermal method; the magnetically modified ceramic particles had greater adsorption capacity for nitrogen and phosphorus than the original ceramic particles, and slightly less than the carbonized modified ceramic particles.
(3) Based on the modification of carbonization, the magnetite modification was carried out by co-precipitation method. After the total amount of adsorption experiments, it was found that although the total amount of ceramic particles after modification was greater than that of the original ceramic particles, it was slightly smaller than that of carbonization alone. Ceramic grain.
Key words: Ceramsite; Surface modification; Hydrothermal method; Co-precipitation method
目 录
摘要 I
ABSTRACT II
第一章 绪论 1
1.1 引言 1
1.2 人工湿地脱氮除磷 1
1.2.1 人工湿地概述 1
1.3 吸附法常用吸附剂分类 3
1.3.1 沸石 4
1.3.2 活性炭 4
1.3.3 凹凸棒 4
1.3.4 陶粒 5
1.4 课题研究意义 6
1.4.1 陶粒存在的问题 6
1.4.2 陶粒表面改性 6
1.4.3 表面荷正电改性 6
1.4.4 于陶粒表面的碳/铁改性 7
第二章 实验试剂与仪器 8
2.1 原料陶粒来源 8
2.2 实验试剂 8
2.3 实验仪器及型号 8
2.4 表征分析 9
2.4.1 X-射线衍射(XRD) 9
2.4.2 扫描电子显微镜(SEM) 9
2.4.3 红外光谱分析(FTIR) 9
2.4.4 比表面积分析仪(BET) 9
2.5 总量吸附实验 9
第三章 陶粒表面炭化改性研究 11
3.1 陶粒表面炭化改性实验 11
3.1.1 实验仪器与试剂 11
3.1.2 陶粒碳化实验方法 11
3.1.2 碳化改性陶粒吸附性能实验 11
3.2 碳改性实验结果 12
3.2.1 SEM表征 12
3.2.2 BET表征 12
3.2.3 XRD表征 13
3.2.4 FTIR表征 13
3.2.5 吸附实验结论 14
3.2.6 葡萄糖水热碳化的形成机理 15
3.3 本章小结 16
第四章 陶粒表面炭/磁改性研究 17
4.1 陶粒表面的炭/磁化改性实验 17
4.1.1 实验仪器与试剂 17
4.1.2 磁/碳改性陶粒制备方法 17
4.1.3 炭/磁改性陶粒总量吸附实验 18
4.2 陶粒MC2制备实验结果与分析 18
4.2.1 SEM表征 18
4.2.2 BET表征 18
4.2.3 XRD表征 18
4.2.4 FTIR表征 19
4.2.5 磁/碳改性陶粒吸附实验 20
4.3 本章小结 21
第五章 结论与展望 22
5.1 结论 22
5.2 展望 22
参考文献 23
陶粒改性及其对氮磷的吸附效果研究
第一章 绪论
1.1 引言
我国市政污泥、疏浚海泥、河道淤泥数量大,亟需处理,资源化利用是有效的缓解我国目前废弃泥处置困境的有效方法;而我国水污染严重,河湖生态环境治理及污水厂尾水提标改造都需耗费大量的湿地基质及填料等基础材料;基于以上两点,本课题组现已将废弃污泥资源化利用,开发成湿地构建的相关基质及填料产品,变废为宝。
人工湿地技术作为一种高效低耗的自然处理工艺,以其优良的特性,已经在世界范围内的污水处理领域得到广泛应用[1]。但人工湿地仍然存在其自身的缺点,如:人工湿地虽然能够去除绝大部分有机物,但其对于氮磷的去除仅为总量的一半。时至今日的人工湿地系统,氮磷的去除机理主要是通过填料的吸附、沉降等作用,总而言之提高填料材料的吸附能力是增强人工湿地系统对氮磷去除的关键。目前市面上采用的填料材料表面多为大孔或中孔,微孔数目少,比表面积小,吸附性能较差。
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