Page 27 - dust collection systems

second), high pressure pulse created by any technique, with
or without a venturi.

As shown in above figure, if a venturi is installed on top of

the tube sheet, the entire bag length can be utilized for

effective filtering as compared to alternative design using a

venturi within the bag.

A major difference between reverse air baghouse cleaning

and pulse jet baghouse cleaning is primarily one of time

scale. The reverse air pulse used in pulse jet baghouse

cleaning is a fraction of a second in duration while the

reverse air cleaned baghouses described in the previous

chapter all use reverse air flow of much longer durations

(tens of seconds).

, in a pulse jet bag filter, individual bags are supported by a

metal/wire/filter cage, which are fastened to the tube sheet

at the top of the casing. The metal cage prevents collapse of

the bag. Dust laden air/gas enters from the bottom of the

casing and flows from outside to inside the bags. the air

passes through the bags (filter media) while solids are

retained on the outside surface of the bags. A signal from the

solid state timer actuates the opening of the normally closed

solenoid valve. Opening of the solenoid valve releases the air

pressure in the tube connecting the solenoid to the
pulse/diaphragm valve, resulting in release of air pressure