Development of Standalone Device for In-Situ Water Quality Monitoring System by Means of UV/Vis Spectroscopy

摘要

UV/Vis spectroscopy provides an accurate analysis in measuring several parameters of water to determine its quality, such as nitrate, nitrite, Total Soluble Solid (TSS) and Chemical Oxygen Demand (COD). However, this method requires a solid state instrument making the measurement need to be conducted in laboratory which not suitable for in-situ measurement. Lately, Microelectromechanical systems (MEMS) technology has been developed which could be used to build a small spectrometer sensor. This gives the opportunity to bring spectrometer sensing on field. The aim of the research is to design and analyze the feasibility of standalone device to measure quality of water combined with chemometric. There are four stages of this research: (1) Acquire spectral data and the major chemical compounds of water; (2) Perform chemometric analysis; (3) Design a bespoke small scale UV/Vis Device for water quality detection; (4) Testing the performance of the instrument. The result showed that the device could only provide coefficient of determination (r~2) of TTS around 0.54 while nitrate parameter resulting 0.43. Even though it could not predict the parameters yet, the prediction system has a potential to be improved by using other robust modeling process.