A Cyclone has different collection efficiency for different size fraction assuming the particles in sphearical shape. 

1.The cylindrical part diameter,length and inlet opening length decides the number of turns happens inside the cyclone for any air flow before leaving through dip tube.

2.The inlet velocity ,cyclone dimeter and number of turns decide the gas residence time in the outer vertex.

3.The gas and material density,viscosity of air,no of turns ,velocity of air decides the cut diameter.

4.Every size fraction's individual efficieny is calculated to get the sigma value of efficiency .

A sheet is attached for quick reference

vdchari

kindly mail me the drop test procedure for cyclone efficience calcukation

Thanks @ rezaisrafil@gmail.com

hello sir 

We have dia3m x len40m kiln we are going to establish 800tpd cement plant 

can you tell us what is the our cyclone diameter size and precalcination size and lenght

out coal 6000kcal / kg 

thank you sir