作者：韦聪, 何美玲, 韦景悦, 冯春华, 韦朝海

作者单位：华南理工大学环境与能源学院, 广东 广州 510006

关键词：化学需氧量;硫酸汞;氯离子;活性炭;分析方法

摘要：

从讨论Cl-对COD的贡献出发，发现Cl-浓度与COD的线性关系和有机物种类无关的规律，在此基础上提出一种无汞测试高氯低有机物浓度废水的COD分析方法的原理。以含氯模拟工业废水为研究对象，该原理的关键技术在于利用活性炭固定床将模拟废水中的有机物彻底分离而保留Cl-，穿透时间是评价有机物与Cl-分离效果的关键影响因素，并关联分析穿透时间与活性炭填充高度、进水流量和有机物初始浓度等因素的作用。结果表明，当活性炭填充高度为13.5 cm，进水流量为1.0 mL/min和有机物初始浓度为100 mg/L时，含氯模拟工业废水均可利用活性炭固定床彻底分离有机物和Cl-；无汞COD分析方法与国家标准方法对含氯模拟工业废水的COD分析存在显著性差异，当Cl-浓度不超过2 000 mg/L时，无汞COD分析方法的实测值在误差范围内与理论值相吻合，标准偏差处在4.11~11.34 mg/L范围内，变异系数的范围为2.19%~11.02%。综合研究认为，基于活性炭分离原理的无汞COD分析方法有望发展成为一种低污染的替代分析技术。

A mercury-free COD analysis principle for simulated industrial wastewater with high-chlorine ion and low-organic concentration

WEI Cong, HE Meiling, WEI Jingyue, FENG Chunhua, WEI Chaohai

School of Environment and Energy, South China University of Technology, Guangzhou 510006, China

Abstract: The contribution of Cl^- to COD was discussed and the law that the linear relationship between Cl^- concentration and COD is independent of organic species was found. A mercury-free COD analysis method for high-chlorine ion and low-organic concentration wastewater was proposed. The key step about this method is that organics are absorbed completely by activated carbon fixed bed and Cl^- is still remained in wastewater using the simulated industrial wastewater as samples. The breakthrough time is the key factor for evaluating separation effectiveness between organics and Cl^-. The influence factors of breakthrough time which are activated carbon bed height, influent flow rate and initial organic concentration was analyzed. Results indicated that organics are absorbed completely by activated carbon fixed bed by bed height 13.5 cm, influent flow rate 1.0 mL/min and initial organic concentration 100 mg/L. There is a significant difference between the proposed mercury-free COD analysis method and national standard method. COD measured value of wastewater samples using the mercury-free COD analysis method is closed to theoretical value within error range on condition of Cl^- concentration less than 2 000 mg/L. Meanwhile, the standard deviation is in the range of 4.11 mg/L to 11.34 mg/L and the coefficient of variation ranges from 2.19% to 11.02%. In summary, the mercury-free COD analysis method is expected to develop into a low-pollution alternative analysis technique.

Keywords: chemical oxygen demand (COD);mercury sulfate;chloride ion;activated carbon;analytical method

2018, 44(11): 1-11  收稿日期: 2018-07-21;收到修改稿日期: 2018-08-15

基金项目: 国家自然科学基金重点项目（21377040，51778238）；广东省应用型科技研发专项基金项目（2015B020235005）；广东省科技计划资助（2015A020215008）

作者简介: 韦聪(1990-),男,广西河池市人,博士研究生,研究方向为环境科学与工程

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