Development and testing of online multi-parameter optical water quality detection module

There are many problems in aquaculture and surface water monitoring, such as difficulty in real-time measurement, difficulty in tracking water pollution source and lack of multi-parameter miniaturized rapid detection equipment. Based on photoelectric detection technology, combined with the principle of light scattering and absorption, using four different wavelength LED light sources, an integrated online multi-parameter water quality monitoring module has been developed. Through highly integrated light path design and light source multiplexing, we overcame the interference caused by turbidity and chromaticity, which has the greatest impact on chemical oxygen demand (COD) detection in water quality detection. By optimizing the design of software and hardware, we used an open detection chamber design to overcome the problems of bubbles in common closed chambers. It realized the rapid measurement of COD, turbidity, chromaticity and total dissolved solids (TDS) in water. The experimental results showed that the correlation coefficients between the measured values and their true values of COD, turbidity and chroma in the standard solution were all above 0.98. The measurement results were in good agreement with the actual values. To sum up, the module is highly integrated, convenient for multi-point online deployment, and can realize rapid real-time monitoring of multiple parameters in the water. It provides new technical means for real-time monitoring of water quality and traceability of pollutants in the water.