Study On Detection Of Water Quality Parameters Based On Spectrometric Method

With the shortage of water resources and the increasingly serious pollution of water source,while the living standards are constantly improving,water quality issues gets more and more attention.Water quality measurement is the premise and basis for water resources protection and management.Chemical Oxygen Demand(COD)index indicate the amount of organic matter in water,and ammonia nitrogen is the main oxygen consuming pollutant in waterbody.Both of them are significant indicators forwater quality detection.In this paper,we designed a small immersion detection system for COD in drinking water and ammonia nitrogen of fisheries,respectively.The main work of this paper isOrganized as follows:1.Consult the literature to understand the detection methods of GB and industry of commonly used water quality parameters,as well as analyze the characteristics and shortcomings of traditional methods and optical methods.Investigate the current research status of water quality parameters detection at home and abroad,and evaluate the performance and cost of existing analytical instruments.besides,new methods that appear in frontier literature is presented.2.Using UV absorption spectrometry to detect COD.The light path and software data acquisition system of drinking water COD detection system was designed according to the requirements of low cost and portable.3.Using fluorescence spectroscopy to detect ammonia nitrogen in water.An ammonia sensitive fluorescence dye is selected,and an ammonia sensitive membrane is prepared through a number of experiments.In order to avoid interference,a layer of waterproof breathable film is further coated on the fluorescent sensitive film,and the performance of different gas-permeable materials is compared and analyzed.Finally,suitable materials are obtained to prepare the ammonia-sensitive fluorescent film.4.The light path structure,circuit control system and data acquisition system of ammonia detection system is designed.Choosing optics to set up optical path;designing light source control circuit and using acquisition card and LabVIEW to achieve control of light sources and acquisition of fluorescence data displayed on the PC.5.The performance testing of the detection system.The standard curve of absorbance and COD concentration is obtained by using the drinking water COD detection system.The system can also distinguish between different types of drinking water and monitor changes in the concentration of COD after the drinking water is placed open.To different concentrations of ammonia,the ammonia detection system designed can produce a different fluorescence response,pH of the solution does not cause interference.