2.3.2
Heat Exchanger
The heat exchanger shall be of the water bath or concentric tube type and
shall be provided with an integral factory-fabricated insulation jacket.
Heat exchanger insulated jacket shall be insulated with a minimum of 40 mm
1-1/2 inches of fiberglass having a density of 12.0 kg per cubic meter 0.75
pcf and a K-factor of 2.15 at 38 degrees C 0.38 at 100 degrees F. The
jacket shall have minimum 16 gauge sides and 5 mm 3/16 inch plate top and
bottom.
2.3.2.1
Sludge Tubes
Sludge tubes shall be standard weight ductile iron pipe with cast iron
return bends with flanged, gasketed connections. Return bends shall be
readily removable for inspection, cleaning, or replacement. Sludge tubes
and return bends shall be large enough to pass a [_____] mm inch diameter
sphere. Sludge tube connections shall be arranged to prevent sludge
contamination of the heating water due to a gasket or connection failure.
2.3.2.2
Pressure Relief Valve
A pressure relief valve, constructed and installed in accordance with ASME
BPVC SEC IV shall be provided. The valve discharge shall be piped to
within 150 mm 6 inches of the floor in full line size.
2.3.3
Burning Equipment
**************************************************************************
NOTE: Delete type of burner and fuel train for
inapplicable fuels.
**************************************************************************
The burning equipment shall be of the capacity to develop the specified
boiler capacity and shall have dual fuel, combination or separate, burners.
The burning equipment shall include equipment for burning either digester
gas, with heat content of approximately 22.3 MJ per cubic meter 600 Btu per
cubic foot and a specific gravity of 0.8, or [No. 2 fuel oil, with heat
content of 39,000 MJ per cubic meter 140,000 Btu per gallon] [natural gas,
with heat content of 37.3 MJ per cubic meter 1,000 Btu per cubic foot or a
mixture of the two gases] [LP gas with heat content of [_____] MJ per cubic
meter Btu per cubic foot]. Gas piping and equipment for LP gas shall
conform to NFPA 58.
2.3.4
Electric Control Panel
A single electric control panel, containing the digester temperature
controller, the burner controller, and the branch circuit breakers and
magnetic starters for the sludge circulating pump, induced or forced draft
fan motor, and heat exchanger water circulating pump shall be provided.
Induced or forced draft fans, motor, and associated boiler and burner
controls shall be in accordance with Section 15561A CENTRAL STEAM
GENERATING SYSTEM COMBINATION GAS AND OIL FIRED. Controllers shall be in
accordance with NEMA ICS 1, circuit breakers shall be in accordance with
NEMA SG 6, and motor controls and motor control centers shall be in
accordance with NEMA ICS 1, NEMA ICS 2, NEMA ICS 3, NEMA ICS 4, NEMA ICS 6,
UL 508, and UL 845. [The control panel shall include provision for
integrating the control function of the building radiation hot water
circulating pump into the control package.] The control panel shall be
SECTION 11380
Page 15
Previous Page
