|Home » Forums » Dust Collection, Safety and Plant Operation » Message||Login|
You are not logged in. Consider these WOODWEB Member advantages:
closed loop system5/22
I have a closed loop bathhouse style system. I have hoppers with airlocks/augers dropping material into a 8" pipe that gets picked up by a 5HP blower and blown into a sealed 40 yard roll off bin. I have 8" flex entering the bin and 8" flex exiting the bin to return air back to the front of the loop. My issue is I seem to have a ton of pressure coming back in and through the "airlocks" creating a air pocket in the hopper above the auger. Therefore backing up the system. Is the issue just my airlock that seems to allow a burst of air between flaps as it rotates? or do i have too much pressure for a standard airlock?
Hello Dan, I know enough to be dangerous so take what I say with a grain of salt.
I was working on setting up a system like that and they spec'd a "Special Venturi Transfer Intake" My understanding of that is it is a special device to create suction at the bottom of the rotary airlock as the air goes by.
Aget Manufacturing in Michigan manufactures them (they are not cheap).
Good luck and report back.
Sounds like the vanes in your airlock are wore out allowing blow by from the transfer fan causing the problems you describe. It is a simple job to replace them. Should also make your collector more effective.
Typically on a closed loop transfer system, the return air coming from your enclosed van needs to be at least 1 inch larger diameter than the air going into it.
I think Tim is correct. You need a 10" return from the hopper, to prevent back pressure.
We have a Belfab closed loop system and they specified 6” going to the trailer and 8” return. They also specified blast gates on each end to create positive or negative pressure on the trailer.