Research And Design Of On-line Pulp Laser Particle Size Analyzer

On-line detection of pulp granularity has been one of the problems before technology researchers.To guarantee the quality of products and optimal control, it is necessary to realize online particle size detection.In this way,we can make the whole production process realize closed loop control.Compared to a variety of particle size distribution measurements,we find that the best method for measuring particle size distribution of the slurry is a laser particle size measurement method. The main problems of traditional laser particle size analyzer is high cost and bad for on-line detection.in order to solve these two problems,we design an online grinding analyzer based on two-color laser.Research work is as follows:Firstly,concepts such as particle size distribution are introduced.Mie scattering theory and measurement principle of laser particle size analyzer were studied.Then,the overall structure of the slurry particle size analyzer was designed,including the transmission unit, an optical system, the receiving unit and the signal processing and control unit.In this paper, the specific hardware and software design were given,using MSP430F149 microcontroller drive line CCD and acquire and process CCD photo-generated electricity signal.At the same time, the display circuit design, communication circuits and power supply circuits were designed.Thirdly,it studied the inversion algorithm of size distribution, namely non-binding algorithm and constraint algorithm which were compared and summarized.And an improved constrained algorithm for slurry particle size measurements was put forward. Finally, a simple experiment platform was set up.Laboratory tests were carried out and particle size distribution results for slag which range from 1 micron to 100 micron were analyzed.Through the study of the subject,the theoretical and experimental study of grinding grain size analyzer based on two-color laser was designed. Experiments show that adopting the line CCD as a photodetector of slurry particle size analyzer and using SCM to collect and process data is feasible.In this way, needs of pulp grinding particle size distribution measurement can be meet.