南京化工职业技术学院

毕业论文（设计）开题报告

学生姓名:

学 号:

院 系:

专 业: 环境监测与治理技术

题 目: COD的测定影响因素的原因

指导教师:

2013年 12月

COD的测定影响因素的原因

摘要：我国已将COD值作为检测水体被污染程度的的主要参数之一，它在环境监测和污染治理中发挥了越来越重要的作用。为进行逐日的控制分析，需要快速、高效的分析方法，以便尽快反映出水质的污染情况。COD的准确测量值对水质的评判非常重要，但是在实验中测定COD往往会受到很多因素的影响。本文就COD测定中的影响因素和改进方法及原理加以探讨，在总结前人研究成果的基础上，根据自己的理解对已有的COD测定影响因素的排除方法作一个总结并提出改进，旨在为污水中COD测定提供系统的参考依据。

关键词：COD；污水；测定；影响因素

Factors affecting the determination of the COD

英文摘要：Our country has been one of the main parameters of the COD value as the detection of water contamination levels, which play an increasingly important role in environmental monitoring and pollution control. For daily control analysis, requires fast and efficient analysis methods in order to reflect the contamination of water as soon as possible. COD accurate measurement of water quality is very important to judge, but the experimental determination of COD is often affected by many factors. In this paper, factors affecting the determination of COD and improved methods and principles to be explored, in summarizing the results of previous studies based on measured according to their own understanding of the factors affecting the existing COD exclusion method and suggest improvements for a summary of the purpose Determination of COD in wastewater delivery systems of reference.

Keyword：COD, Sewage, Determination, Factors

目录

1.绪论 ................................................................................................................ 1

1.1研究背景 ................................................................................................................... 1 1.2研究的目的与意义 ................................................................................................... 1 1.3国内外研究现状 ....................................................................................................... 2 1.4本论文的研究思路 ................................................................................................... 3

2. COD的测定方法介绍 ................................................................................. 3

2.1重络酸钾法 ............................................................................................................... 3 2.2分光度法 ................................................................................................................... 4 2.3臭氧法 ....................................................................................................................... 4 2.4新型测量方法 ........................................................................................................... 5

2.4.1电化学法 ........................................................................................................ 5 2.4.2极谱法 ............................................................................................................ 5 2.4.3原子吸收法 .................................................................................................... 5 2.4.4光催化法 ........................................................................................................ 6

3. 影响COD测量的因素与消除 ................................................................... 6

3.1水中还原性物质的干扰及消除方法 ....................................................................... 6

3.1.1Cl-的干扰及消除 ............................................................................................ 6 3.2空白试验值的影响及解决方法 ............................................................................... 8

3.2.1硫酸质量对空白值影响及解决方法 ............................................................ 8 3.2.2实验用水对空白值影响及解决方法 ............................................................ 8 3.2.3试剂浓度对空白值及测定的影响 ................................................................ 8 3.3水样的保存与均化影响与消除 ............................................................................... 9 3.4重铬酸钾浓度的影响 ............................................................................................. 10 3.5其它影响因素的排除 ............................................................................................. 11

4.COD测定方法的设计与改进 .................................................................... 11

4.1实验部分 ................................................................................................................. 11

4.1.1实验原理 ...................................................................................................... 11 4.1.2实验仪器和试剂 .......................................................................................... 13

4.1.3实验步骤 ...................................................................................................... 14 4.1.4 注意事项 ..................................................................................................... 14 4.2结果与讨论 ............................................................................................................. 15

4.2.1硫酸亚铁铵浓度的计算 .............................................................................. 15 4.2.2 含乙醇溶液的CODCr值测定结果 ......................................................... 15 4.2.3含甲醇溶液的CODCr值测定结果 ............................................................ 16 4.2.4含甲苯，乙苯和苯酚溶液的CODCr值测定结果 .................................... 17 4.2.5 未知水样CODCr值测定结果 ................................................................. 18 4.3实验结论 ................................................................................................................. 18 4.4改进建议 ................................................................................................................. 19

5. 总结 ............................................................................................................ 20 附 录 ........................................................................................................... 20

附录一 ：仪器的使用说明 ......................................................................................... 20 附录二：我国水处理行业的现状 ............................................................................... 22

参考文献 ......................................................................................................... 24 致谢 ................................................................................................................. 25