The application is a dust collection system. The duct from the various pieces of equipment is taken to a bag filter and from there to a carbon bed and then to a second carbon bed before the air is discharged by the fan. The bag filter has a pr. drop of 5 inches, and each carbon bed has 10 inches of pr. drop. The duct in question is between the filter and the first carbon bed, between the carbon beds and then to the fan. The duct is 18" round.
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