Exhaust requirement for dust tank.

[pfrey]

I have a tank that fills at a known rate (14000 lb/min) and the material density (51 lb/cu ft). I am trying to verify that my dust collection system is drawing enough air to prevent dusting. Basically, I want CFM in less than CFM out. I applied a formula I found (CFM= lb/min divided by lb/cu ft). This seems correct. Am I overlooking key points? By the way, my dust collector says it's pulling aprox 400 cfm and I calculate 275 cfm going into the tank.

 

[Chance17]

Your analysis looks OK. Lets see if I understand.
275 cfm represents actual air displaced by the solids.
125 cfm is extra air input to remove dust.
The total dust collector load is 400 cfm.
Correct ??

 

[pfrey]

You are correct. Thanks for the confirmation!