Charging Characteristics of Sulfur powder in Elbow of Pneumatic Conveying System

Abstract Eliminating static electricity is a difficult thing for pneumatic conveying. In this paper, the most representative powder sulfur is selected as the research object. Therefore, in order to study the influence of pipe elbows on the charging characteristics, pneumatic conveying experimental platform was applied to conduct experiments to investigate the synergistic effects of airflow velocity, particle mass flow rate, particle water content and particle size on the charge characteristics, and the optimal ratio of elbow was designed. The results show that, when the particle size was constant, the charge-mass ratio increases with the increase of the airflow velocity, showing a linear positive relationship and increases firstly and then decreases with the increase of mass flow. When the airflow velocity was constant, particles were -40 μm, the effect of particle size on the charge-mass ratio becomes more significant. When the particle size was +40 μm, the charge-mass ratio of sulfur powder increases with the decrease of particle size, the influence is not notable. When the mass flow kept constant, the charge-mass ratio of sulfur powder increases as the particle size decreases. When the water content increases from 0 to 0.4%, the charge-mass ratio decreases by 14.3%-16.9%. However, if the water content continues to increase, the charge-mass ratio is stable. The charge-mass ratio of sulfur powder decreases with the increase of the bend ratio of right-angle elbow. As the technological layout is satisfied, the bend ratio can be increased to the range from 2.5D to 3D appropriately. This research can give reference to the design of sulfur powder pneumatic conveying system, so that the reasonable system ratio can be ensured.