2.3
FUEL BURNING EQUIPMENT
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NOTE: The designer must include all the required
data for proper design of the boiler. Delete all
references to coal and stokers where oil is the only
fuel to be utilized.
Paragraphs describing stoker equipment not required
shall be deleted. Stokers and stoking equipment
selected will be based on the following:
Boilers having output capacities of 3,517 kW
(12,000,000 Btuh) or more will be equipped with
mechanically-driven grates operating continuously or
intermittently. Dump grates will not be permitted
in boilers in this size range. Spreader stokers
will be specified when bituminous coal with ash
content on a dry basis in excess of eight percent or
ash fusion temperature lower than 1200 degrees C
(2,200 degrees F) is to be used. Pulsating grate
units will be water-cooled and complete with
automatic coal feed and continuous ash removal.
Conveyor stokers may be specified if suitable for
the type of coal available. Chain or traveling
grate may be specified by deletion of one type of
grate, or the choice between the two types may be
left to the Contractor by including both types in
the description. The following is a general guide
in determining which type of grates to investigate:
__________________________________________________________________________
MW Output
(Size) Type of Grate and Stoker
__________________________________________________________________________
735 - 5860
Single retort, stationary grate, underfeed
stokers
5860 - 8800
Single retort, moving grate, underfeed stoker
1465 - 22000
Reciprocating grate, front continuous ash
discharge stoker
1465 - 29500
Vibrating conveyor grate, front continuous ash
discharge stoker
5860 - 36500
Water-cooled, incline grate, hopper fed
vibrating grate stoker
8800 - 120,000
Spreader stoker, continuous front ash discharge
__________________________________________________________________________
__________________________________________________________________________
(MBtuh Output
(Size) Type of Grate and Stoker
__________________________________________________________________________
2,500 - 20,000
Single retort, stationary grate, underfeed
SECTION 15555A
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