Waste collection vehicle
From Wikipedia, the free encyclopedia
A waste collection vehicle (WCV)/ refuse collection vehicle (RCV), garbage truck (in North America), rubbish truck (in Australia), or dustcart, or sometimes dustbin wagon (in Britain and other Commonwealth countries), is a truck specially designed to pick up smaller quantities of waste and haul it to landfills and other recycling or treatment facilities. They are a common sight in most urban areas.
Contents |
[edit] Types of waste collection vehicle
There are five basic models of waste collection vehicles:
- Front loaders
- Rear loaders
- Automated Side loaders (ASL)
- Pneumatic collection
- Grapple trucks
[edit] Front loaders
Front loaders generally service commercial and industrial businesses using large waste containers with plastic lids [dumpsters (US) or wheelie bins (UK)]. The truck is equipped with automated forks on the front which the driver carefully aligns with sleeves on the waste container using a joystick or a set of levers. The waste container is then lifted over the truck. Once it gets to the top the container is then flipped upside down and the waste or recyclable material is emptied into the vehicle's hopper. Once the waste is dumped, it is compacted by a large blade called a "packer blade" that pushes the waste to the rear of the vehicle. Most of the newer WCVs have "pack-on-the-go hydraulics" which lets the driver pack loads while driving, allowing faster route times.
[edit] Rear loaders
Rear loaders commonly service residential areas. They have an opening at the rear that a waste collector can throw waste bags or empty the contents of bins into. Often in many areas they have a lifting mechanism to automatically empty large carts called toters without the operator having to lift the waste by hand. Typical bin sizes are 35-95 gallon carts.
Another popular system for the rear loader is a rear load container specially built to fit a groove in the truck. The truck will have a wire / chain or strap system for lifting in the two "eyes" on the rear top. The waste will then slide into the tray of the truck. Normal sizes are 6 to 22 m³. The disadvantage of the large containers is that it requires a lot of free space upwards, while the smaller bins never reach higher than the truck itself.
The rear loader usually compacts the waste with a sweep-and-slide system that digs in the waste and compresses it against a moving wall, that will move it towards the front of the vehicle as the pressure forces the hydraulic valves to open.
[edit] Automated Side Loaders (ASL)
Photo: see "Sideloader" under "external links"
Side loaders are trucks very similar to front end loaders. The differences are that a side loader only picks up smaller containers such as toters. 96,64 and 35 gallon trash carts with attached lids commonly used for residential waste collection. Automated Side Loaders are mostly used only in residential areas. Another difference is that ASL trucks pick the container up over the side and not over the front. The mechanical arm can have a reach of up to 9 feet, which allows trash to be collected around obstacles such as parked cars, mail boxes etc. The arm is operated by either a joystick just like a front end loader or by four switches. An ASL truck only uses one operator where as a traditional rear load garbage truck in town areas often require two or three people; driver and one or two men unloading trash bins.
[edit] Pneumatic collection WCVs
Pneumatic collection WCVs have a crane with a tube and a mouthpiece that fits in a hole, usually hidden under a plate under the street. From here it will suck up waste from an underground installation. The system usually allows the driver to "pick up" the waste, even if the access is blocked by cars, snow or other barriers.
[edit] Grapple trucks
Grapple trucks enable the collection of bulky waste. A large percentage of items in the solid waste stream are too large or too heavy to be safely lifted by hand into traditional WCVs. These items (furniture, large appliances, branches, logs) are called bulky waste or "oversized". The preferred method for collecting these items is with a grapple truck. Grapple trucks have hydraulic knucklebooms, tipped with a clamshell bucket, and usually include a dump body or trailer.
[edit] History
Wagons and other means had been used for centuries to haul away solid waste. Trucks were first used for this purpose soon after their invention. The 1920s first saw open topped WCVs used for the purpose, but soon covered vehicles became used more often. The open tops tended to drop waste and had poor odours. These covered trucks were first introduced in more densely populated Europe than in North America, but were soon used everywhere.
The covered vehicles were still modified dump trucks, however. The main difficulty was that the waste collectors needed to lift the waste to shoulder height. The first technique developed in the late 20s to solve this problem was to build round compartments with massive corkscrews that would lift the load and bring it away from the rear. A more efficient model was the development of the hopper in 1929. It solved this problem by developed a cable system that a could pull waste into the truck.
In 1937 George Dempster invented the Dempster-Dumpster system in which wheeled waste containers were mechanically tipped into the WCV. His containers were known as Dumpsters, which led to the word dumpster entering the language.
In 1938 the Garwood Load Packer revolutionized the industry when the notion of including a compactor in the truck was implemented. The first primitive compactor could double a truck's capacity. This was made possible by the availability of relatively cheap hydraulic presses.
1955 saw the Dempster Dumpmaster the first front loader introduced. They do not become common until the 1970s, however. The 1970s also saw the introduction of smaller dumpsters, often known as wheelie bins which were also emptied mechanically.
Since that time there has been little dramatic change. Compactor designs however, have been many and varied, one of the most popular being the traditional "sweep and slide" system where hydraulically-powered plates scoop out the waste from a loading hopper and subsequently compact it against the material already loaded. The Heil Colectomatic used a combination of a lifting loading hopper and a sweeper blade to clear and compact waste in anticipation of the next load.
So-called "continuous" compactors were popular in the 1960s and 1970s. The German Shark design (later Rotopress) used a huge rotating drum, analogous to a cement mixer, in conjunction with a serrated auger to grind down and compact the garbage. SEMAT-Rey of France pioneered the rotating rake system (also used in the British Shelvoke and Drewry Revopak) to both mutilate waste and break down large items. High fuel consumption has seen a decline in the popularity of continuously compacting garbage trucks.
In the mid 1970's Petersen Industries introduced the first grapple truck for municipal waste collection.
In 1997 Lee Rathbun, introduced the Lightning Rear Steer System. This system is unique because it includes an elevated, rear-facing cab for both driving the truck and operating the loader. This configuration allows the operator to follow behind haul trucks and load continuously.
There has long been the dream of the fully automated WCV that could do away with all but the driver. Some cities do have these systems (see Side Loader above), but they are generally unable to deal with unexpected situations.
[edit] See also
[edit] External links
[edit] General
- History of refuse collection - Historical information and many pictures of WCVs.
- Classicrefusetrucks.com - History of mechanical refuse collection equipment
- Sideloader truck - picture
[edit] Manufacturers
- Garbage Trucks - Heil Environmental, history of the oldest U.S. garbage truck maker, modern garbage trucks
- Garbage Trucks - Information and images of Freightliner garbage trucks and how they work.
- Grapple Trucks - Information on and pictures of Petersen Industries grapple trucks. Site also includes links to articles and editorials on bulky trash and grapple trucks.
- Grapple Trucks - Vortex Truck and Equipment, Information and pictures of grapple trucks
