air filters used for air conditioning applications

1. EZHIL RAJ.S
AIR FILTERS
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2.  Air filter is a device composed of fibrous materials.
 It removes solid particulates such
as dust, pollen, mould, and bacteria from the air.
 Air filters are used in applications where air quality
is important, notably in building ventilation systems .
Air filter
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3. Coarse filters
Fine filters
HEPA
ULPA
Carbon Air Filters
UV light air filters
TYPES
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4.  A prefilter used in air-conditioning systems to remove large
particles such as dust and lint.
 This type of filter is usually reusable after being vacuumed or
washed.
 Range from less than 50 microns to 2000 microns.
COARSE FILTERS
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5.  HEPA is an acronym for “High Efficiency Particulate Air”
 This type of air filter can remove at least 99.97% of dust,
pollen, mold, bacteria and any airborne particles with a size
of 0.3 micrometers (μm)
HEPA FILTER
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6. ULPA is an acronym for "Ultra Low Penetration
Air (filter)"
An ULPA filter can remove from the air at least
99.999% .
 With a size of 100 nanometres (0.1 µm) or
larger.
ULPA FILTERS
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7.  It can readily be used to absorb particles and
trap odors.
Carbon air filters use activated carbon to trap
chemicals and gases, and can also filter
cigarette smoke
CARBON AIR FILTERS
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8. Ultraviolet light air filters use a reaction that
occurs when titanium dioxide is exposed to UV
light.
High intensity UV (240-280 nm) is strong
enough to break down most carbon based
organic compounds, making UV light air filters
a good companion to HEP filters in medical
applications
UV LIGHT AIR FILTERS
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9.  Filters with higher efficiency will have higher pressure drop.
 pressure drop can be calculated by
PRESSURE DROP
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10.  It shows how well a filter removes airborne particles.
 the filtration efficiency E, can be calculated by
 Where,
Cdown is the average concentration of particles at the
downstream location.
Cup is the average concentration of particles at the
upstream location before the filter.
FILTRATION EFFICIENCY
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11.  It is a function of the filtration area.
 The velocity of the air is given by
V=Q/A
where,
Q is the volumetric flow rate through the filter
A is the filtration area.
The standard HEPA filter has an initial 1.0 in. w.c. (249 Pa)
pressure drop at 250 fpm (1.3 m/s) face velocity.
A high capacity HEPA filter has a 1.4 in. w.c. (348 Pa) pressure
drop at 500 fpm (2.5 m/s), with the same quality air filtration
AIR VELOCITY
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12. FILTRATION EFFICIENCY FOR TWO
DIFFERENT VELOCITIES
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13.  Air Velocity Through The Filter Medium.
Particle Size.
Dust Loading On The Filter.
 Filter Packing Density.
 Fiber Diameter And Thickness Of The
Material.
FACTORS THAT AFFECT FILTRATION
EFFICIENCY
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14. Hospital operation theatre
Clean room in medical industry
Toxic environment
Air conditioning
Maintain proper IAQ in living room , office etc
APPLICATIONS
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