Develpoment Of The On-line Monitoring Flue Dust Concentration

With the development of Modern industry and Technology, more accuracy means are needed by all kinds of measurements of dust concentration and granularity. Whether or not to meet these challenges is not only a question about environment, but also a question which concerns healthy of people. The technology on this field is drawing much more attentions.The online flue monitor is a kind of instrument that is built on the Lambert law and the Mie scattering theory. In order to work out the concentration of dust flue based on the theories, we need 2 kinds of data stream, one is the attenuation of laser beam, the other is the diameter of dust, also be called granularity. The former type of the instrument can not process Real-time diameter data, and it works based on a fixed diameter datum in particular situation in which the diameter of dust is previously adopted to correct the result by standard methods.In this paper, in order to work out the average diameter of dust, we need 2 stream of laser to work out the ratio of scattering light of the laser, and then the average diameter of dust. In order to calculate out concentration, we need another 2 streams of laser to work out the attenuation of trans-laser, and then calculate out the concentration. All together, 4 ways of laser are applied in the system. The first pair of beams of laser act as trans-laser and comparison laser to collect the comparison of trans-laser, the other 2 beams act together to collect the ratio of scattering light, which is needed to work out the granularity of dust.The new monitor gathers data from 2 pairs of photoelectric detectors (OPT301) by using C8051F005. both the attenuation of laser and average diameter of dust are calculated by C8051F005.The paper has describe the following content mainly:(1) Summary of online measurement of flue dust;(2) While measuring the density of dust using penetrating law and mere scattering law, analysis of what influence that the scattering angle, light wave and the grain size have on the concentration of dust , and the result that the choosed scattering angle impact on the measurement of the grain size;(3) Analysis of the differences between the light source laser and infrared source laser;(4) Design, debug and build of hardware;(5) Online programming and lab debug of software;(6) Error analysis.