Predicting cyclone emissions with a new computer mode

Abstract

Cyclone emission tests were conducted on 1 D-3D and 2D-2D cyclones with varied outlet tube sizes and inlet velocities. Talc and wheat dusts were used in testing the laboratory scale models. Data from these tests were used in developing a mathematical computer model capable of predicting outlet dust emissions given the following input variables: dust type and inlet concentration. inlet air velocity, and cyclone type. The model was developed based on the observation that a cyclone fractional efficiency curve (FEC) resembled a normal distribution's cumulative distribution function (CDF). The cut-point and sharpness-of-cut of the FEC were correlated to the mean and standard deviation of the normal distribution's CDF, respectively. The model also estimated cyclone pressure drops based on given inlet velocities. Results showed that the correlation of parameters was indeed acceptable. Actual versus program generated emission concentrations were similar, with the estimated emissions being slightly higher. Actual test results showed 1 D-3D emission concentrations being less than 2D-2D emissions under similar conditions. Reduced cyclone outlet sizes increased cyclone dust collection efficiencies, but with higher pressure drops. Lower than design inlet velocities reduced cyclone dust collection efficiencies. There was minimal collection efficiency difference between beaded cone and smooth cone cyclones. Tests with extended cyclone outlet tubes versus design outlet tubes also showed minimal collection efficiency differences.