Air pollution control equipments are used to regulate or negate various system emissions. It can be found in a wide range of manufacturing, processing, research and production facilities. In case, air cleaning and purifying systems are used to provide a healthy and contaminant-free work environment, while in others they are in place to prevent the escape of harmful chemicals, vapors or dust into the air.
Common varieties of air pollution control equipment include scrubbers, dust collectors, Bag House Filters and electrostatic precipitators.
Cyclones, a fairly widespread type of control equipment; spin polluted vapors at high-speed. Gravity forces the heavier materials (the pollutants and dust) to the edge of the spinning vapors, where it is collected. Air flows in a helical pattern, beginning at the top (wide end) of the cyclone and ending at the bottom (narrow) end before exiting the cyclone in a straight stream through the center of the cyclone and out the top. Larger (denser) particles in the rotating stream have too much inertia to follow the tight curve of the stream and strike the outside wall, then fall to the bottom of the cyclone where they can be removed. The lighter, pollutant-free fumes are then released. These systems, along with a tremendous variety of other specialized or unique pollution control devices are in place at factories and production facilities like Woodworking shops, pharmaceutical manufacturers, cotton gins, rock crushes, and cement plants.
Bag House Filter
Bag filters use fabric bags to remove particles from dust-laden gas.
They can achieve high efficiencies for fine particles because of the build-up of particles on either the inside oe outside surface of the bag depending on the design.
As dust builds up, the pressure across the beg increases, so the filters need regular cleaning. Mechanical shaking using a reverse airflow or a pulse of compressed air are used to dislodge the dust from the fabric surface, which then falls by gravity into a collection systems.
- Have high collection efficiency for respirable dust
- Can use strong woven bags, which can withstand intensified cleaning cycle to reduce residual dust buildup
- Simple to operate
- Have low pressure drop for equivalent collection efficiencies