Research And Design Of Multi-parameter On-line Monitor For Groundwater Quality

Since the First-five-year Plan of National Economy Development,China has made great progress in the industrial field.However,rapid development has brought a series of environmental problems,among which groundwater pollution is one of them.In recent years,with the enhancement of national environmental awareness,groundwater pollution has begun to receive widespread attention.In the latest five-year plan,the country has listed groundwater resource monitoring as one of the major tasks.The realization of on-line monitoring of groundwater quality is the key to this task.On-line monitoring of groundwater quality is an important part of water resources protection.It can provide real-time water quality data for monitoring personnel.When water resources are polluted,early warning information can be issued in a timely manner.Based on the development status of the on-line groundwater quality inspection system at home and abroad,this project proposes a multi-parameter remote online monitoring scheme for groundwater quality based on UV-spectrophotometry,and designs a monitoring prototype according to the scheme.The specific research content can be categorized as follows:(1)According to the current situation of water quality monitoring and development at home and abroad,several commonly used water quality monitoring methods are compared.Combined with the characteristics of groundwater monitoring,the principle of UV-spectrophotometric detection of water quality and data processing methods are introduced,and the noise of the photodiode preamplifier circuit of the monitoring system is theoretically analyzed.(2)Completed the development and commissioning of on-line monitoring prototypes for groundwater quality chemical oxygen demand,total organic carbon,nitrate nitrogen,and turbidity,including three parts: system structure process design,system hardware circuit design,and system software design.(3)According to the analysis of noise theory,complete the configuration of the parameters of the photodiode preamplifier circuit components,and use PSpice software to simulate and verify;complete the mathematical modeling and verification experiments of TOC and COD correlation(two groundwaters in Hangzhou City);Completion of mathematical modeling and confirmatory experiments of turbidity compensation of groundwater with turbidity in the range of 0~100NTU.(4)According to the ultraviolet(UV)absorption of water quality automatic online monitor technical requirements specification standards,the monitoring of the prototype performance indicators for testing.(6)Summarize the research content of the project and analyze and look forward to the issues that still need to be studied.