电镀厂废水处理
学 院:
专 业:
姓 名:
指导老师:
机械与车辆学院
机械工程及自动化
辛超
学 号:
职 称:
070401031032
王立涛、王 五
教授、助教
中国·珠海
二○一三年五月
摘 要
电镀是世界三大污染行业之一,随着我国乡镇电镀企业的迅速发展,我国的电镀污染问题日趋严重。本文首先阐述了我国电镀废水的污染现状以及对人类产生的危害,在对化学处理、离子交换、电解法、生物处理等电镀废水处理方法的分析和比较后,结合乡镇电镀企业要求工艺简单、成本低等特点,决定采用NaHSO3化学还原沉淀法处理该企业的含铬、锌废水。本工艺是在pH=2.5时用NaHSO3溶液将Cr6+还原为Cr3+,在用NaOH溶液调节pH=8后生成Cr(OH)3和Zn(OH)2沉淀,在添加絮凝剂PAM后生成的絮体在斜板沉淀池中沉淀,出水经过滤器过滤后可回用于过滤器反冲洗水及各种溶液的配制,或者达标排放,而污泥则统一交于专业的环保公司处理。在设计中采用了较为先进的ORP测定仪、在线pH计和液位计实现反应过程的自动控制。通过设计计算确定了各构筑物的尺寸以及设备的选型,并对设计和操作管理中的要求进行了说明,最后对电镀废水治理的前景进行了展望。
关键词:电镀废水;Cr;Zn
ABSTRACT
With the speedy development of the electroplating enterprise in towns in our country, electroplating industry,as one of the biggest pollutions in the world,causes the pollution more and more severely。
In this paper, describes the present situation of the electroplating effluent water pollution and the great harm it makes to the human kind has been described. After the analyses and the comparison of different ways for treatment of electroplating effluent such as chemical treatment process、ion exchange process、electrolytic method and biological process, I decide to adopt the NaHSO3 reduction-precipitation to treat the waste water containing Cr and Zn for the corporations, considering the features of the town electroplating corporations'demands of simple techniques, low costs, etc.This technology is to deoxidize Cr6+into Cr3+ by NaHSO3 solution at the pH=2.5,then adjust the pH to 8 with NaOH solution to make Cr(OH)3 and Zn(OH)2 sediment.The flocculating constituent,formed after adding the flocculating agent PAM, can be deposited in the sloping plank settling tank. The water left after filtrating through a sank filter can be recycled as the backwash of sank filter and be used in confecting various solutions or be discharged an emission standard.And, the sludge can be solved by the professional environmental protecting companies.It adopts some relatively advanced equipment such as measuring element of ORP、pH meter and content gauge realize the automata of the reaction process.Through elaborate designation and calculation,the size of each construct and the type election of the equipment have been ascertained.Besides,with explanations about the designation and the demands in the operating management,it finally comes to the prospect of solving the problem of the waste water from plating.
Keyword: electroplating effluent;chromium ;zinc
目 录
第一章 电镀行业环境保护现状 - 1 -
1.1 中国电镀行业概况 - 1 -
1.2 电镀污染现状 - 1 -
1.3 电镀废水的危害性 - 3 -
1.4 电镀废水处理方法 - 5 -
第二章 设计背景 - 9 -
2.1 项目概况和意义 - 9 -
2.2 设计条件 - 9 -
2.3 设计原则 - 9 -
第三章 处理工艺的确定 - 10 -
3.1 工艺流程选择 - 10 -
3.2 工艺流程说明 - 11 -
3.3 工艺条件控制 - 12 -
第四章 单体构筑物的设计计算 - 13 -
4.1 调节池 - 13 -
4.2 反应池 - 14 -
4.3 斜板沉淀池 - 16 -
4.4 中间水池 - 21 -
4.5 过滤器 - 22 -
4.6 清水池 - 24 -
4.7 药剂投配系统 - 24 -
4.8 污泥处理系统 - 25 -
第五章 管网布置与水力计算 - 28 -
5.1 平面布置 - 28 -
5.2 高程布置原则 - 28 -
5.3 水力计算 - 28 -
第六章 设计管理要求 - 32 -
6.1 设备与材料要求 - 32 -
6.2 电气控制系统设计要求 - 32 -
6.3 处理药剂及药品消耗 - 33 -
6.4 操作管理注意事项 - 33 -
6.5 劳动定员 - 34 -
第七章 工程概算 - 36 -
7.1 设备工程 - 36 -
7.2 土建工程 - 36 -
7.3 运行费用与处理成本测算 - 37 -
7.4 电镀废水治理发展前景 - 38 -
参考文献 - 40 -
致 谢 - 41 -