How does it work??
Hot, high pressure continuous blowdown water
drained from the boiler contains valuable heat energy.
The continuous blowdown process helps control boiler
water quality and operating efficiency by removing
suspended and dissolved solids from the water in the
boiler drum.
Recovery of up to 50% of the BTU's available may be
accomplished by generating low pressure flash steam in a
flash tank. This supply of steam can be used in
the boiler D/A tank or other low pressure steam
applications. As the flash steam is generated, the
blowdown condensate that remains is used to preheat the
boiler feed water using a low pressure liquid to liquid
heat exchanger.
For smaller, lower pressure blowdown requirements, the
HX Series heat recovery systems utilize a higher
pressure liquid to liquid heat exchanger without a flash
tank to do the heat recovery job.
Madden
System Features
Type HV and Type HC
- No solids buildup. Madden systems are self
flushing, designed to use gravity flow to continuously
clean itself. They operate without becoming
clogged or fouled with solids contained in the dirty
blowdown water.
- Low pressure heat exchangers in the Type HC and Type
HV systems - this reduces stress on equipment and makes
scale buildup unlikely on the cooling side of the heat
exchanger tubes. This is because the temperature
rise of the makeup water cooling medium will usually be
no more than 20° F.
- Flash tanks designed for blowdown - baffles on the
blowdown inlet create water droplets and turbulence to
enlarge the surface area and increase flashing.
Adequate vessel volume produces clean steam without
water carryover. Surface area and retention time
are engineered to facilitate flashing. |
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What is Continuous Top
Blowdown? |
| To prevent scale buildup and to
insure high steam quality and boiler operating
efficiency, boiler water quality specifications must
be maintained. Chemical treatment alone can't
do the job, so water containing concentrated
dissolved and suspended mineral solids is removed
continuously through a top blowdown system. As
the dirty blowdown water is removed from the boiler
drum, it is replaced with fresh makeup water which
improves the boiler water quality. Too much
blowdown wastes heat and chemical treatment.
Too little blowdown results in operation and
maintenance problems. To get the full benefits
of blowdown heat recovery, the blowdown flow must be
continuous, not intermittent. |
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