Investigation On Properties Of Laser-induced Plasma Spectroscopy Of Coal With Different Carbon Chcmical Forms And Signal Collections

With the unit capacity of coal power plants continue to increase as well as the strongerneeds of the energy conservation, a component of coal as fired online detection technology isin urgent need. Laser-induced breakdown spectroscopy(LIBS) is a rising material compositionand concentration analysis technique based on atomic emission spectroscopy in nearly fourdecades with the characteristic of minimal damage to sample, fast analysis speed,multi-element simultaneous analysis. LIBS has demonstrated great potential in coal as firedcomponents online detection in the field of combustion.The process and mechanism of the interaction of the coal matrix and laser are the key toreally applying LIBS to the online analysis of coal quality. Domestic and foreign scholarshave done a certain amount of work in this regard. This paper has carried on followingresearch on characteristics of laser induced breakdown spectroscopy of coal by a method ofcombining the theoretical knowledge and experimental analysis:The process and the basic characteristics of the spectral lines were introduced in detail.Meanwhile, the quantitative calibration models were presented. Also, the establishing of thebasis equipment of laser-induced breakdown spectroscopy and the cold state suction typewind powder device were in detailed description.The different atmospheres (air, nitrogen, argon) were used to analyze the differences ofplasma mechanisms of atomic emission and molecular emission with different carbon forms,The results showed that the variation rules of C2molecular emission intensities are similarwith neutral atomic emission CI for the carbon materials with different forms. However, thevariation rule of CN molecular emission is different, which mainly depends on the structuralcharacteristics of samples and the interaction mechanism between the plasma and surroundingenvironment.Aiming at the physical form of coal as fired in actual power plants--pulverized coalflow, the plasma emission spectrometry signal characteristics in different optical collectionswere analyzed on the cold state suction type wind powder device, The analysis results showthat for the pulverized coal flow, the stability of the lines collected by back-side are better,while the counts of the lines collected by side are stronger.Finally, a summarization was given and the prospect was proposed for probably work.