Air Filtration
The first step in energy-efficient air filtration design is
to determine accurately rather than estimate the filtration
required for the laboratory's process needs and for safety.
Close attention to filtration efficiency will result in significant
energy use reductions over the life of the facility, especially
when the optimization of the filter's final pressure drop is
calculated.
The next step in designing energy-efficient filtration is reducing
pressure loss in filter systems by selecting filters with the
lowest pressure drop available, usually those with deep, extended
surfaces; underrating filter bank(s) by sizing for reduced volume
compared to the rated filter volume; and designing the filter
bank for a low face velocity of no more than 300 feet per minute
(100 feet per minute is best for energy-efficient design). Since
filter life is inversely proportional to the square of velocity,
cutting velocity in half can extend filter life by a factor
of four. Some High-Efficiency Particulate Air (HEPA) filters
cause less pressure drop than the filters typically included
in conventional supply systems; HEPA filtration does not necessitate
large pressure drops.
The features described above will cost more than conventional
designs partly because of their requirements for increased duct
size and filter area. However, these recommendations are usually
shown to be cost effective when life-cycle cost analysis is
done.
Follow the links below for more information from US Labs21 on
the following:
Degree
of filtration (US specific)
Filter
Pressure Drop
Electronic
vs Media Filtration
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