Donaldson Torit fabric filters are becoming the leading brand of bag filters used in baghouse dust collectors. They are useful in removing many different types and sizes of dust particles. Still, a question exists. How efficient are they?
In the past, a weight basis was used to determine the efficiency of fabric filters. This was done by conducting a weight efficiency test, which measures how much weight was filtered out compared to what passed through the filter. The weight efficiency test was conducted using a dust sample that had particles of multiple different sizes. One main problem with this is that larger particles, which are more easily filtered out, make up most of the original dust sample’s weight. This would then assign the filter a very high efficiency percentage based on weight, even if there was a higher amount of fine particles that did not get filtered out.
Now, there is a more accurate measure of fabric filter efficiency. This is called the fractional efficiency curve. It is tested by running a sample of dust of similar small particle sizes through the filter. Having the particles all the same size more accurately shows the true percentage of dust particles that are filtered out. The fractional efficiency curve shows the efficiency of the filters for different particle sizes. This curve shows that the efficiency of these filters increases exponentially with larger particle size.
Donaldson Torit fabric filters also have several other features that set them apart from other filters. The Donaldson Torit Dura-Life bag filters last, on average, 2-3 times longer than standard 16 oz. polyester bag filters. Dura-Life bag filters are the standard filter used on all Donaldson Torit baghouse dust collectors. They are also available as replacements for all other brands of baghouse dust collectors.