shall have micrometer capacity adjustment from 0-100 percent while the
chemical feed pump is running and metering accuracy within plus or minus
one (1) percent. Chemical feed pump components shall be constructed of
materials suitable for the chemicals being pumped. Drive motors shall be
120 volts ac, 60 Hz, single phase, with general purpose dripproof
enclosure. Chemical feed tank shall be fabricated of materials suitable
for chemicals used and shall be provided with fill and chemical feed drain
connections and gauge glass. Chemical feed tank shall be furnished with
one chemical feed pump, mounted and piped with piping and fittings
constructed of materials suitable for the chemicals being pumped, and shall
include a suction strainer and 13 mm 1/2 inch relief valve. Chemical feed
tank shall have hinged cover. Chemical feed tank bottom shall be dished
concave to radius equal to diameter of tank.
2.11.2
Agitator
Chemical feed tank shall be equipped with agitator. Agitator shall be
motor driven with Type 316 stainless steel impeller and drive shaft.
Maximum speed shall be 1750 rpm. Agitator and support shall be mounted on
of chemical feed tank.
2.11.3
Boiler Chemical Treatment System
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NOTE: For steam boiler plant with more than one
boiler select a bulk storage system 800 liters (200
gallons) for each chemical or dedicated feeder
system for each chemical with individual drums 200
liters.(50 gallons) for the chemical treatment for
**************************************************************************
The following shall be provided for each boiler:
a.
Three (3) chemical feed pumps. Each pump shall be provided with a
pressure relief valve piped on discharge side of the pump to
divert overpressurized chemical solution back to the storage tank.
Chemical feed pumps shall have capability of accepting 4 to 20 mA
dc signal.
b.
[One (1) 800 liter 200 gallon bulk storage tank.]
c.
[Three (3) 200 liter 50 gallon drums.]
d.
be 1650 kPa 225 psig and maximum temperature shall be 120 degrees
C 250 degrees F. Water meters shall be turbine type with cast
iron Maine cases.
e.
Proportional chemical feed controller and electronic pulse timer.
Pulse timer shall control proportional feed of treatment chemicals
based on feedwater as measured by a contacting head water meter.
Controller shall have following features:
(1)
Painted steel NEMA 12 enclosure.
(2) Panel display including: proportional pulse timer,
automatic-off-manual switch, push-to-test momentary switch which
simulates a water meter pulse and runs the timer for one cycle,
SECTION 15561A
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