摘要
水环境污染的治理与预防均要求水质检测能够实时化、在线化以及便携化。水质参数如化学需氧量（COD）和硝酸盐氮的在线监测，通常需要泵阀管路的实验室化学方法的现场化，分析时间长，需化学试剂和废液回收。研制了一种基于紫外光谱法的在线测定COD和硝酸盐氮的水质监测系统。它由脉冲氙灯、凹面全息光栅和光谱扫描结构等组成，可以同时测定水样在200～720nm的光谱。棒状仪器直接投入水中，通过计算水样紫外吸光度测定水中COD和硝酸盐氮的质量浓度。
This paper is aimed to make a research advance review on the submersible water-quality monitoring systems on the basis of the spectral ultraviolet principle. As is known, water pollution control and prevention has been more and more demanding to call for real- time, online and portability in testing and controlling the water quali- ty. Online monitoring in this way even asks for providing such param- eters as chemical oxygen demand （COD）and nitrate nitrogen, which used to be gained in the laboratory through chemical experiments with the help of valves and pipes, and, therefore, ask for a longer analy- sis time and chemical reagents and waste recycling. To overcome such inconveniences and meet the above, we are inclined to introduce an online testing technology of direct determination of COD and ni- trate nitrogen content based on the ultraviolet absorption, which is by nature a kind of online detection technology without chemical reagents and pre-treatment samples. We have also introduced in this paper a novel water quality monitoring system for COD and nitrate nitrogen based on UV-visible spectrometry, consisting of a pulsed xenon lamp, concave holographic grating and a spectral scanning structure, which is capable to determine any spectrum of water in the 200 - 720 nm range. By using a rod-like instrument that can be put into the wa- ter to do the testing directly, detecting the COD and nitrate nitrogen concentration in the water by testing the UV absorbance. In so doing, the above mentioned methods can be adopted to classify the samples through a series of experiments with standard solution of the potassium hydrogen phthalate and standard solution of the Potassium nitrate. In addition, we have also found a suitable mathematical model to test water for its contaminants from the database so as tn enhance the abil- ity of the UV water testing technology and gain other water quality in- dices. Besides the above review, we have also done some water sam- ples experiments ourselves to raise the availability and feasibility of the instruments under test by means of actual water samples of COD and nitrate nitrogen content prepared by ourselves. Thus, it can be seen that the above technical review and our own research activities are expected to provide a new kind of green detection technology for surveying the pollution sources and monitoring of surface water origins such as that in lakes, rivers and so on.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2012年第6期98-102,共5页
Journal of Safety and Environment
基金
国家自然科学基金项目(11074134)
天津市科技支撑计划项目(10ZCKFSH02200)
国家重大科学仪器项目(2011YQ15004008)
关键词
光谱学
水质监测
化学需氧量
硝酸盐氮
紫外吸收
spectroscopy
water quality monitoring
chemical oxygen demand
nitrate nitrogen
UV absorption
