In our plant we are having a pfister feeder ( fine coal feeding to kiln firing) from the fine coal silo. The coal flow is as follows....

fine coal silo-agitator-rotary air lock-calibration bin- pfister

We have a venting line to bag filter from the calibration bin.

we are facing a problem of positive pressure in the vent line given to bag filter from the bin. Also there is rush out of coal from the rotary air lock.

Please guide us in this regard.................

Thank you ■