MIL-HDBK-1003/6
Waste Oil. The use of waste oil as a supplementary fuel should be
5.4.2.6
undertaken only with proper precautionary measures to ensure that the oil does
not contain products that will damage equipment or generate pollutants that
will be harmful to the environment.
5.4.3
Natural Gas
5.4.3.1
Applications. Furnish the equipment and piping called for in ANSI
Z223.1, National Fuel Gas Code/NFPA 54. Consult with the gas transmission
company to determine whether gas will be supplied on a continuous or
interruptible basis.
Metering and Meter Locations. Gas meters shall be selected and
5.4.3.2
located according to criteria in ANSI Z223.1/NFPA 54. The utility company
should be consulted to determine whether it will provide the metering station
with accessories, housing, connecting pipeline, and if the utility has
specific piping requirements. In addition to the main plant meter, individual
meters shall be provided for each boiler.
Pressures. Where the supplied gas pressure is too low for the
5.4.3.3
required burner turn-down range, use a pressure blower (radial vane or paddle
wheel type; refer to MIL-HDBK-1003/8, Exterior Distribution of Utility Steam,
HTW, CHW, Natural Gas, and Compressed Air) to add to its rated pressure to
obtain the proper burner pressure. Allow for pressure drops in piping and
burner control valves in computing the pressure regulator valve setting.
Venting. Gas mains, burner headers, gas piping, etc., shall be
5.4.3.4
vented according to the criteria in NFPA 85A, Prevention of Furnace Explosions
Singe Burner Boiler-Furnaces and NFPA 85B, Prevention of Furnace Explosions in
Gas Multi-Burner Boiler.
Wood. Wood products potentially available as fuel for generating
5.4.4
steam in central heating plants are hogged, wood chips, sawdust and bark.
Appropriate dust control measures shall be taken to prevent explosive mixtures
of dust from being present in the plant. Handling and storage of sawdust
pellets must be in accordance with ANSI/NFPA 664, Wood Processing and
Woodworking Facilities.
Wood Delivery. Since wood burning is mainly confined to areas
5.4.4.1
where it is locally available as a by-product or waste, most deliveries are by
truck. Unloading wood from trailers can be accomplished with truck dumpers,
which tilt the trailers and allow chips to fall into an unloading hopper.
Wood Handling Equipment. Belt conveyors with suitable fire
5.4.4.2
protection should be used for transporting wood waste from storage to surge
bins. These surge bins supply the distributors (mechanical or pneumatic)
which feed the wood waste into the boilers. Surge and storage bins should all
have counter-rotating screws on the bottom to minimize bridging of stored wood
chips.
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