基于O3/UV法的消解终止自动确定方法

为了提高基于臭氧协同紫外（O₃/UV）法的COD在线监测装置的检测效率和检测精度，分析了不同水样在消解过程中二氧化碳气体生成浓度的变化率与有机物消解率之间的关系，提出了一种消解终止自动确定的检测方法.通过采集消解过程中各传感器的数据，基于使用滑动标准偏差法计算二氧化碳气体浓度变化率的标准差自动确定消解终止时间.对不同种类、不同浓度的有机物进行消解实验，发现在二氧化碳实时浓度的标准差小于0.003时，有机物基本消解完全，可认为达到反应终点.该方法不仅可用于COD的在线监测提高检测效率和检测精度，也对基于臭氧协同紫外（O₃/UV）法的废水处理具有指导意义.

An automatic determination method of digestion termination based on O3/UV method

In order to improve the detection accuracy and efficiency for the on-line monitoring device of chemical oxygen demand (COD) by using Ozone in combination with Ultraviolet Radiation (O₃/UV), the relationship between the concentration change rate of the produced carbon dioxide (CO₂) and the digestion rate of organics is analyzed in the digestion of different water samples, a method is further proposed to automatically determine the termination of digestion. Based on the data collected by each sensor during the digestion process, the standard deviation of CO₂ gas concentration change rate is calculated using the moving block standard deviation (MBSD) method, which is applied to automatically determine the termination time of digestion. Digestion experiments with organics of different types and different centration reveal that organics are completely degraded when the standard deviation of CO₂ concentration is less than 0.003, which can be considered as the end point of the reaction. This method can not only improve the detection accuracy and efficiency for the on-line monitoring device of COD, but also has guiding significance to the treatment of wastewater based on O₃/UV method.