重金属废水处理工艺设计
Heavy metal wastewater treatment process
design
学 院：理 学 院 专 业 班 级：环境工程1001班 学 号：100704128 学 生 姓 名：郜 月
指 导 教 师：李 艳 平 （副教授）
2014 年 6 月
摘 要
目前，水污染问题已经成为全球性普遍问题，严重影响了人类的生存和社会经济的发展并且越来越受到人们的高度重视。因此，治理水污染，保护水资源已经成为人类的目标。
随着我国电镀行业的日趋发展，电镀废水作为世界三大污染之一，对于当今提倡环保的时代来说是特别值得重视的处理项目。众所周知，电镀行业会产生大量含重金属的废水，而重金属废水中含有大量的有毒物质，如果不经处理直接外排会造成严重的水体污染。因此，对电镀行业中废水中的重金属的处理至关重要。废水的化学处理及物理处理都是净化污水的重要手段，而二者的结合是更加有效的方法。
本文首先描述了我国重金属废水的处理意义，电镀重金属的危害以及电镀废水处理的基本现状和处理方法，结合本次设计中浙江省某电镀厂的实际情况和处理要求，决定采用化学和物理相结合的办法来处理重金属废水，化学法中是采用了中和法与絮凝法，而物理法中则是采用了物理沉淀法。此次工艺所采取的方法简便易操作且原理简单。利用絮凝反应对于含铬废水应首先在酸性条件下投加还原剂，将Cr6+还原成Cr3+，然后加Ca(OH)2进行化学沉淀处理。对于铜离子、锌离子、镍离子等通过加氢氧化钙调节PH，进行中和沉淀处理。
关键词：含铬废水;重金属废水;沉淀法。
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Abstract
At present,water pollution problem has become a global common problem,a serious impact on the survival of humanity and the social and economic development,and attaches great importance to more and more human.Therefor, to control water pollution and protect water resource have become a human target .
With the speedy development of the electroplating enterprise in our country,electroplating,as one of the biggest pollutions in the world,cause the pollution more and more severely. As we all know ,electroplating can produce wastewater with a lot of heavy metal ions ,and heavy metal wastewater also has many of toxic substances,which direct efflux without treatment will cause serious water pollution.So,it is important to remove heavy metal of the wastewater in the electroplating .Chemical and physical treatment of wastewater treatment is an important means of purifying sewage，however，The combination of the two approaches is more effective.
This paper first describes the significance of heavy metals in waste water treatment，the hazardous of heavy metal plating ,basic status of electroplating wastewater treatment and treatment .For example (Biological , Physical chemistry ,Electrochemical ,Chemical method ), then combined with the actual conditions and processing requirements of a electroplating factory in Zhejiang province ,it is decide to use the combination of Physical method and Chemical method to treat the wastewater .Chemical method is the use of a neutralization method with flocculation. The physical method is the use of physical precipitation. The approach taken in the process simple and easy to operate and simple principle. For the use of chromium-containing wastewater flocculation reaction under acidic conditions should first be adding a reducing agent, the reduction of Cr6 + to Cr3 +, then add Ca (OH) 2 for chemical precipitation treatment. For copper ion, zinc ion, nickel ion, PH adjusted by calcium hydroxide, and for the precipitation treatment.
Key words: wastewater containing chromium; heavy metal wastewater; method of precipitation.
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目 录
摘 要 .................................................................. I Abstract ................................................................. II 第1章 绪 论 ............................................................ 1
1.1 重金属废水的处理意义 .............................................. 1 1.2 电镀行业重金属废水的危害 .......................................... 1 1.3 电镀行业重金属废水处理的基本现状 .................................. 2 1.4 电镀重金属废水处理方法 ............................................ 2
1.4.1 生物法 ...................................................... 2 1.4.2物化法 ...................................................... 3 1.4.3 电化学法 .................................................... 3 1.4.4 化学法 ...................................................... 4
第2章 设计依据及内容 .................................................... 6
2.1 自然资源 .......................................................... 6
2.1.1 厂址地理概况 ................................................ 6 2.1.2 气候特点 .................................................... 6 2.1.3 地质资料 .................................................... 6 2.2设计内容及要求 .................................................... 7
2.2.1 工程概况 .................................................... 7 2.2.2 设计依据 .................................................... 7 2.2.3 电镀重金属废水处理后的水质要求 .............................. 7 2.2.4 水质水量 .................................................... 7
第3章 污水处理工艺方案的确定 ............................................. 8
3.1处理站选择 ........................................................ 8 3.2 设计要求 .......................................................... 8
3.2.1 设计规模 .................................................... 8 3.2.2 水质水量及处理要求 .......................................... 8 3.3 设计原则 .......................................................... 9 3.4 工艺方案与工艺流程 ................................................ 9 第4章 主要处理构筑物的计算 ............................................. 11
4.1 反应调节池 ....................................................... 11
4.1.1 设计参数 .................................................. 11
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4.1.2工艺尺寸 ................................................... 11 4.1.3 进出口及液位 ............................................... 11 4.1.4 提升泵 ..................................................... 12 4.1.5调节池水泵扬程计算 ......................................... 12 4.2 中和池1 ......................................................... 13
4.2.1设计参数 ................................................... 13 4.2.2工艺尺寸 ................................................... 13 4.2.3 进出口及液位 ............................................... 13 4.3絮凝反应池1 ...................................................... 13
4.3.1设计参数 ................................................... 13 4.3.2工艺尺寸 ................................................... 14 4.3.3 进出口及液位 ............................................... 14 4.4沉淀池1 .......................................................... 14
4.4.1 参数选取 ................................................... 14 4.4.2 工艺尺寸设计 ............................................... 15 4.5 生物接触氧化池 ................................................... 16
4.5.1设计参数 ................................................... 16 4.5.2生物接触氧化池填料容积 ..................................... 16 4.5.3生物接触氧化池总面积 ....................................... 17 4.5.4 设计计算 ................................................... 17 4.5.5 污水与填料接触时间 ......................................... 17 4.5.6 接触氧化池总高度 ........................................... 17 4.5.7 生物接触氧化池需气量计算 ................................... 18 4.5.8 空气管道计算 ............................................... 19 4.6调节池2 .......................................................... 19
4.6.1设计参数 ................................................... 19 4.6.2工艺尺寸 ................................................... 19 4.6.3 进出口及液位 ............................................... 20 4.6.4 配套设备 ................................................... 20 4.6.5调节池水泵扬程计算 ......................................... 20 4.7中和池 2 ......................................................... 21
4.7.1 设计参数 ................................................... 21 4.7.2 工艺尺寸 ................................................... 21
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