How will be the excess filter ratio affects the particulate removal efficiency?
a) Excessive filter ratios – ‘Filter ratio’ is defined as the ratio of the carrier gas volume to gross filter area, per minute flow of the gas. Excessive filter ratios lower particulate removal efficiency and result in increased bag wear. Therefore, low filter ratios are recommended.
How is dust collector capacity calculated?
For a rectangular port, calculate the area (multiply length times width, in inches). Then, multiply that area times 28 to find the approximate flow in CFM @ 4,000 feet per minute (FPM).
How do you calculate air to fabric ratio?
To calculate air-to-cloth ratio, take the amount of airflow (CFM) and divide that by the amount of filter area within your dust collector. For example, if you’re calculating for a cartridge collector, a typical range would be a 4:1 air to cloth ratio.
How do you calculate air-to-cloth ratio in a bag filter?
Simply put, the air-to-cloth ratio of a filter is the amount of air flowing through each square foot of filter media each minute. To calculate the air-to-cloth ratio for your dust collector, divide the airflow in cubic feet per minute by the total square footage of the filter media in all of the cartridges.
What are baghouse filters what pollutant does this target?
Mercury – baghouse fabrics are coated with powdered activated carbon to absorb mercury or other difficult to capture air pollutants. Toxic media – unit is capable of filtering toxic materials such as dust, mist, fume, or smoke from the air.
How do baghouse filters work?
Baghouse systems are engineered to collect, capture, and separate dust and particulates from the air. The gas stream then passes through the filters, while particles remain on the filter media surface, thus separating the particulates from the air.
How do you calculate filter efficiency?
The efficiency of the filter can be calculated directly from the beta ratio because the percent capture efficiency is ((beta-1)/beta) x 100. A filter with a beta of 10 at five microns is thus said to be 90 percent efficient at removing particles five microns and larger.
How does the air to cloth ratio affect the baghouse?
Maintaining an adequate air to cloth ratio enables the baghouse to operate at peak efficiencies, collecting more than 99.9% all dust particles that pass through it.
How is CFM generated in a baghouse?
Most often baghouses are sized and categorized according to CFM. In general, the larger the space being vented or the greater the number of pickup points in the system the more CFM required. The CFM generated by the system fan can be fixed or adjusted (Variable Frequency Drive or VFD Fans).
How is suction measured in a baghouse system?
– Vacuum pressure or suction is measured in inches of water gauge, w.g. and is the basis of a properly functioning dust collection system. The system fan must supply enough suction to pull the materials from the collection point (s) all the way through the ductwork to the baghouse and then through the filters and out to exhaust.
How are baghouses used to control air pollution?
Well-designed and operated baghouses have been shown to be capable of reducing overall particulate emissions to less than 0.05 g/m3 (0.010 gr/ft3), and in a number of cases, to as low as 0.002 to 0.011 g/m3 (0.001 to 0.005 gr/ft3).