Page 142 - Materials Chemistry, Second Edition

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Municipal Solid Waste Collection 113

TABLE 5.2
Factors to Consider in Selecting Waste Collection Equipment

Loading Location Loading and Unloading Mechanisms
Compactor trucks are loaded on the side, back, or front. Loading mechanisms should be considered for com-
Front-loading compactors are often used with self-load- mercial and industrial applications, and for residences
ing mechanisms and dumpsters. Rear loaders are often when municipalities wish to minimize labor costs over
used for both self and manual loading. Side loaders are capital costs. A variety of unloading mechanisms are
more likely to be used for manual loading and are often available
considered more efficient than back-loaders when the
Design Considerations—Loading
driver does some or all of the loading
• Labor costs of collection crew
• Time required for loading
Truck Body or Container Capacity • Interference from overhead obstructions such as tele-
3
Compactor capacities range from 10 to 45 yd .
phone and power lines
Containers associated with hauled systems generally • Weight of waste containers
3
have a capacity range of 6 to 50 yd . To select the opti-
Design Considerations—Unloading
mum capacity for a particular community, the best trade-
off between labor and equipment costs should be • Height of truck in unloading position. Especially
determined. Larger capacity bodies may have higher cap- important when trucks will be unloaded in a building
ital, operating, and maintenance costs • Reliability and maintenance requirements of hydraulic
Heavier trucks may increase wear and tear, and corre- unloading system device
sponding maintenance costs for residential streets and
Truck Turning Radius
alleys
Radius should be as short as possible, especially when
Design Considerations part of route includes cul-de-sacs or alleys. Short wheel-
• The loading speed of the crew and the collection base chassis are available when tight turning areas will
method used be encountered
• Road width and weight limits (consider weight of both
waste and vehicle) Watertightness
• Capacity should be related to the quantity of wastes Truck body must be watertight so that liquids from waste
collected on each route. Ideally, capacity should be an do not escape
integral number of full loads
• Travel time to transfer station or disposal site, and the Safety and Comfort
probable life of that facility Vehicles should be designed to minimize the danger to
• Relative costs of labor and capital solid waste collection crews
Design Considerations
Chassis Selection
• Carefully designed safety devices associated with
Chassis are similar for all collection bodies and materials
compactor should include quick-stop buttons. In
collected
addition, they should be easy to operate and
Design Considerations convenient
• Size of truck body. Important for chassis to be large • Truck should have platforms and good handholds so
enough to hold truck body filled with solid waste that crew members can ride safely on the vehicle
• Road width and weight limitations (also need to con- • Cabs should have room for crew members and their
sider waste and truck body weight) belongings
• Air emissions control regulations • Racks for tools and other equipment should be
• Desired design features to address harsh treatment supplied
(e.g., driving slowly, frequent starting and stopping, • Safety equipment requirements should be met
heavy traffic and heavy loads) include the following: • Trucks should include audible back-up warning
high-torque engine, balanced weight distribution, good device
brakes, good visibility, heavy-duty transmission, and • Larger trucks with impeded backview should have a
power brakes and steering video camera and a cab-mounted monitor screen
(continued)