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An O-type water tube boiler
represents an alternate way of designing
water tube boilers. It is symmetrical, well
balanced and very compact compared to D-type
boilers and A-type boilers.
Capacities for O-type package units can go
as high as 250,000 lbs/hr (115 tons/hr) with
pressures up to 1500 psig (103 bar) and
temperatures up to 1050 oF (565
C). It is appropriate where space is
limited. It can be field erected if required
by site conditions or for size larger than
250,000 lbs/hr (115 tons/hr). It can fire
any fuel but may be less appropriate to fire
no.6 oil than an A-type or D-type boiler. |
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Solid fuels like wood wastes
cannot be fired in the O-type furnace and if
used have to be burned in separate
combustion chamber. The boiler then is used
as a waste heat recovery boiler.
Super heaters are radiant and convective
type and produce quite stable superheated
steam temperatures over all firing range
.That design can be built with membrane
water walls or with tangent tubes. Furnace
sizes are smaller than a D-type or an A-type
and will result in higher heat release rates
influencing NOx levels. They are also used
as heat recovery steam generators. O-types
are popular as portable boilers and boilers
for rents. They are often use for
cogeneration, petrochemical industries,
industrial processes etc.
It is a well balanced boiler design. O-type
boilers are easier to ship by road or by
train than D-type boilers because of the
fact that their shape will ease the passage
through tunnels or bridges and that their
center of gravity is on the center of the
unit.
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Specifications |
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Capacities |
From 10,000 lbs/hr to
80,000 lbs/hr with or without super
heater |
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Pressures |
250 psig (17
bars) design up to 1500 psig (103
bars) |
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Super heaters |
Temperature up to
1050 oF . |
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Fuels |
Oil, gas or
combination |
-Membrane or tangent
tube wall construction to ASME code
section I
-Optional water cooled membrane rear
wall
-Optional water cooled membrane
front wall and burner throat
-Steam purity up to 1 ppm |
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