Data Acquisition And Control System Software Design Of Laser-Induced Breakdown Spectroscopy Sewage Detection Device

Industrial sewage discharge is the main cause of water pollution and the main source of the toxic metallic element in water. The traditional technologies which are used to detect the industry sewage couldn't satisfy the needs of on-line, real-time and continuous monitoring in industry. Laser-Induced Breakdown Spectroscopy (LIBS) is a new type of component analysis technique. It is widely recognized as one of the best online detecting methods for industrial wastewater in the world. A device has been developed for sewage detection by LIBS in lab. The software part work of the device was introduced in this thesis, such as the real-time data acquisition, data analysis, data processing of spectrum signal, device automatic control and so on. The industrial sewage from a certain chemical plant was detected with the device and the results showed the software program meets the detection requirements. The main research contents include:1) Using Visual C + + programming language and Labview graphical programming language, the Laser-Induced Breakdown Spectroscopy signal data of heavy metal element in sewage were collected and analyzed. The underlying function of data acquisition card and some specific control module were generated dynamical link library with Visual C + +. And they were transplanted into Labview flat, by a specific graphical programming language to realize all tasks.2) The data processing in some practical LIBS application were realized with corresponding algorithm. By taking full advantage of Labview programming language in data processing all algorithm procedure were written. The effective spectral signal data and the eigenvalue were obtained. The elements spectrum signal database was established.3) Through software programming, the spectrometer was synchronously and accurately controlled and high precise position was realized as the wavelength scanning. The spectrometer data acquisition control system software was programmed with Labview, it's functions included spectrum signal acquisition, the stepping motor revolving speed and direction control, time synchronization, etc. The software would effectively eliminate the measurement error by manual work.4) A LIBS detection device was set up to verify whether the software control section meet the requirements. Through the realization of the time evolution experiment, the data stability processing, element calibration curve, detection limit and the theoretical analysis, the experimental results showed the software meets the design requirements and the setup could be used to measure the sewage from factory.All the work was an important part of study on the detection device of industrial sewage with LIBS technology. The software programming ideas, programming techniques, algorithm and some specific function modules, which were dealt with in this thesis, will help for LIBS application on other areas (gas, soil, mud, etc.) and provide technical support.