Development Of The Instrument For Detecting The Ozone Disinfection Effect In Water Based On Improved ORP Method

In order to raise the monitoring level of disinfection effect in the process of water treatment that using ozone as sanitizer, a kind of oxidation-reduction potential (ORP) method which belongs to electrochemistry technology is proposed. The problems, the solutions and also the development of detecting instrument are studied when using this method.Via the comparison of many kinds of detecting methods that using ozone as sanitizer in water, the remaining concentration of sanitizer is pointed out not to be a better instrument to reflect the disinfection effect. As highly related with the disinfection effect, the ORP method is adopted.The principle of ORP method, the principle of disinfection detecting, together with the standard and characters of ORP are studied in this article. Via analyzing the data and experiment, the flow rate and temperature are pointed out to be the factors which influence the stability of the ORP detecting when using ozone as sanitizer in water.In the process of ORP detecting the flow rate and temperature can affect the result, the reasons are analyzed and the improved methods are given in this article. In order to solve the flow rate problem, the method of revolving solution is adopted to control the flow rate and strike up the electrodes' homeostasis; the temperature compensation is applied in order to solve the temperature affection to the standard potential of reference electrode. The best flow rate range is 1.83～2.2m/s by the flow rate affection experiment.The holistic design theory of the instrument whose core is the high performance ATmega8 MCU is introduced in this paper, and realized in both hardware and software. The EMC design for both hardware and software is considered to improve the instrument's anti-interference ability.The experimental results show that the instrument for detecting the ozone disinfection effect in water based on improved ORP method is feasible; moreover it also has many advantages, such as fast response, high precision and convenient maintenance. So it will have a great application foreground.