Water Quality Monitoring System Design Based On Algae Chlorophyll Fluorescence Kinetics Curves

With the rapid development of social economy, water consumption in industry,agriculture and residents living is increasing, which produce large amounts of thecorresponding industrial wastewater, agricultural wastewater and domestic wastewater.Industrial wastewater often contains heavy metals, which is easy to cause the animalsand plants death; agricultural and domestic wastewater discharged into waters willcausewaters eutrophication, algae and phytoplankton in the water blooms and producered tide. Therefore, water pollution has brought great harm to human life, productionand life and health.Algae contain chlorophyll, which can be used as an indicator of water qualitymonitoring. Quick accessing algae chlorophyll fluorescence kinetics can monitor waterquality, and play a great role in the water quality pollution early warning. In this paper,chlorophyll fluorescence kinetics is used as a measurement to monitor waterpollution.First to obtain algae in the water, certain wavelengths of light is used tostimulate algae chlorophyll fluorescence signal, and plot the kinetic curves.Contrastingwith the health of the kinetic curves of the algae can determine whether the water iscontamination. The following are the main contents of this paper.①Compared the current water quality testing methods and analyzed the currentsituation of water quality testing at home and abroad, we proposed a new method todetect water quality-algae chlorophyll fluorescence method;②Studied the basic principles of fluorescence measurements and proposed generalscheme of algae chlorophyll fluorescence detection system;③Designed Optical of the system and taken advantage of weak signal detectiontechnology lock-in amplifier technology to build the hardware circuit photoelectricdetection system, and designedlow-pass filter to filter out stray light signal toobtainfluorescence signal;④Researched fluorescence signal acquisition hardware circuit about MSP430F149,and developedthe related software for data acquisition;⑤Studied the method of extracting chlorophyll, and used the spectrometer toobtain the optimum excitation and emission wavelength ofchlorophyll. Acquired thefluorescence kinetics of chlorophyll fluorescence kinetics and chlorella, andanalyzedthecurve. Experimental results show that the fluorescence kinetics curves measured by thesystem derived from algae important instructions to verify the role in monitoring waterpollution; and modular, small size, low power consumption design of the system is notonly beneficial to install the system, commissioning and maintenance, but alsoconducive to integrated systems with other systems; while portable systems, stability,and low cost advantages for multi-point dispatched to monitor pollution of the waters,the waters of the overall monitoring is important.