atomizer wheel, and operational monitoring and control system. Atomizers
supplied under this paragraph shall be of the rotary design and shall have
a proven record of efficient and reliable service in previous lime slurry
applications. Provide atomizers with quick disconnects on the atomizer
motor and feed system to allow rapid changeout of atomizers while the steam
generators are on-line. The atomizers motor drive shall be as specified in
paragraph entitled "Pumps, Valves, Motors." The transmission connecting
the drive motor to the atomizer shall be of the belt or gear-box type. The
transmission assembly shall be designed to produce the wheel tip speed
required for proper slurry atomization over the range of operating
conditions, and shall be provided with a simple means of changing the wheel
tip speed, so that the design value can be changed if operational
experience indicates the need for adjustment. The wheel tip speed shall be
a minimum of 137 meters per second 450 feet per second. Gear units shall
comply with all applicable AGMA standards. Bearings shall be the
manufacturer's standard design for this application. Bearings shall have
an operating life of at least 6,000 hours. Provide a complete lubrication
system for each installed atomizer including necessary pumps, reservoirs,
filters, heat exchangers, piping, valves, instrumentation and controls, and
other accessories, as required, to circulate, clean, and cool the
lubricating oil for the atomizer drive and transmission bearings. The
lubrication system shall be designed with redundant features and controls
required to provide safe and reliable operation of the atomizer and to
prevent damage to the atomizer motor or transmission assembly due to loss
of lubrication. The atomizer wheel shall be designed so that parts exposed
to abrasion from the slurry are wear resistant and replaceable. The wheel
body shall be constructed of stainless steel. The orifices in the wheel
shall be provided with silicon carbide inserts. The wheel shall be
dynamically balanced to minimize vibration of the atomizer unit. Provide
instrumentation and controls as specified in Section entitled
"Instrumentation and Controls." Include as a minimum the monitoring of the
following atomizer operating conditions: motor amperage, lubricating oil
pressure, oil temperature, oil reservoir level, motor temperature, atomizer
vibration, slurry feed rate, and water feed rate. One complete, ready to
run, spare atomizer including motor and drive shall be provided for the
Flue Gas Cleaning System. Provide two stands for storing one spare
atomizer in an upright position. Provide a stand to hold one atomizer for
maintenance. Provide two complete, ready to install, spare atomizer
wheels. Two complete sets of tools, as required to disassemble and
assemble the entire atomizer, shall be provided. Atomizers shall be
designed so that normal maintenance can be performed by plant maintenance
personnel who have been trained, as specified in paragraph entitled
"Operator Training Program."
2.7.2.2
Two-Fluid Nozzle Atomizers
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NOTE: Alternate arrangement applicable only when
plant design includes idle boiler at plant maximum
demand load.
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Provide multiple-slurry atomizers for each spray dryer absorber, each with
its own flue gas plenum to ensure adequate contact of the flue gas with the
atomized slurry. Atomizers supplied under this paragraph shall be of the
two-fluid nozzle design using compressed air as the atomizing fluid and
shall have a proven record of efficient and reliable service in previous
lime slurry applications. Atomizers shall be provided with quick
disconnects on the compressed air and lime slurry feed lines to allow rapid
SECTION 15864N
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