Ash Analysis
Percent
MgO
[_____]
Na(2)O
[_____]
K(2)O
[_____]
SO(3)
[_____]
Ash Fusion Temperatures
Degrees C
Initial deformation temperature
[_____]
Softening temperature
[_____]
Fluid temperature
[_____]
Ash Fusion Temperatures
Degrees F
Initial deformation temperature
[_____]
Softening temperature
[_____]
Fluid temperature
[_____]
2.3.1
Spreader Stokers
Spreader stokers shall be the overfeed self-feeding type suitable for
burning a portion of the coal in suspension, but sized assuming 100 percent
combustion on the grate. [Coal shall be evenly distributed across the full
width of the grate by not less than [_____] feeder units. Unit shall be
designed for operation of any feeder independently of the others, or it
shall be possible to operate all feeders simultaneously.] Feeders shall be
capable of handling and uniformly distributing coal over the grate area.
Feeders shall be the mechanical-rotating type, shall have no moving parts
within the combustion chamber, and where moving parts are exposed to
excessive heat, such parts shall have all bearings protected by suitable
water jackets. Grease or oil lubrication shall be provided for all
bearings. Stoker shall be designed for readily adjustable feed
distribution of coal on the grates.
2.3.1.1
Grates
Grates for spreader stoker firing shall be high air resistant type and
arranged for powered mechanical or compressed air actuated dumping in
sections. Openings shall provide proper distribution of air under the fuel
bed. [Grates shall be in sections to match the feeders with provisions for
shutting off the forced draft to each section so that any section of the
grate can be cleaned while the others remain in service.] Grates shall be
heavy-duty, heat-resisting cast-iron. Mechanical dumping shall be with
[air-] [water-] actuated power cylinders connected to the grates, and
grates shall be furnished complete with cylinders, linkages, valves, and
piping as required. Each section shall dump independently of other
sections. Necessary over fire air jets complete with fans, ducts, and air
control valves shall be provided as required for proper turbulence and
combustion. Grate drives shall be independent of feeder drives to provide
independent speed variation of feeders and grates.
2.3.1.2
Traveling Grates
Traveling grates shall be high air resistant type especially designed for
spreader stoker firing and for continuous ash discharge. Openings shall
provide proper distribution of air under the fuel bed. Grates shall be
heavy-duty, heat-resisting cast-iron, and individual sections shall be
replaceable without taking the grate out of service. Air seals around
SECTION 15555A
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