Design And Verify Of Water Ammonia Nitrogen Detection System

With the deepening of the process of industrialization, the environmental problems are facing severe challenges. Fresh water is also polluted because of industrial wastewater and domestic sewage by the wanton pollution emissions. From the point of view to construct a practical optical detection system, the building process of the system and problems encountered was described. To verify the system's reliability after it was complete, a solution of known concentration was tested.During the project, optical design and optimization was done through lens optimization. A xenon lamp was selected as light source based on the basic principles of spectrophotometry. A control system was established based on a set of AVR microcontroller to receive and test signal, some of the small circuit module can also be used for other applications. Finally, the self-built system was used to test the solutions of different concentrations of ammonia nitrogen based on Nessler basic principle to ensure the system can work well. This photoelectric detection system, can be used not only in water quality testing of the concentration of ammonia nitrogen, but also can be used in relevant research work in the future.Through the system design and analysis of chemical processes, Nessler reagent is a strong ammonia concentration testing methods, the Nessler reagent contains some toxic ingredients, experiments need to pay attention to anti-virus preparations. The design of the detection system need to consider how to better control the completion of the beam, the system noise need to be controlled as small as possible. while preparing Nessler's reagent solution, strict control of reagent is needed to ensure the controllability of sample concentration and experimental result's unity.