Differential Pressure Measurement across Baghouse

Differential Pressure Measurement across Baghouse is very important to determine the filtering efficiency of the baghouse fan. The increased differential pressure across the baghouse ( bag dust collector) shows that there is jamming inside the bags. Jamming may be due to clogging of the bags.

The manufacturer specifies the rated pressure drop across BDC (Baghouse dust collector).


The baghouse dust collector has long, cylindrical bags. The bags are made of fabric. The main function of the bags is to filter dust particles out of the air stream. The dust-laden air- the air that has lots of dust, smoke, and impurities- enters the baghouse.

The baghouse fan creates the suction or draft to direct the dust-laden air into the BDC. Dirty air enters in the inlet of BDC, passes through the bags, it gets cleaned here, and exits from the outlet of the BDC. The dust collected in the bags dislodges into the BDC hopper during purging of the air through the solenoid valve. The efficiency of the dust collectors also depends on the air purging cycle.

The clean air can be released into the environment or reused in the process

Differential Pressure Measurement across Baghouse

The differential pressure measures the flow in the stream. The clogged bags cause hindrance to flow of air stream. As a result, the differential pressure increases across the baghouse. The DP transmitter’s pressure measurement indicates how clogged the bags are.

The DP transmitter gives a signal to the BDC controller when the DP reaches above the set point. The BDC controller issues command to the solenoid valve at a faster rate to bring the differential pressure down.

The bag choking problem increases if the bag’s cleaning is not perfect during purging. The pressure of the purge air is very important in the cleaning process. If the control air pressure is low than the rated purge air pressure, it can beget the problem of bags chocking gradually.