The Recycling Process
By Danielle and Saadiqah
Trash, trash, and more trash; itís everywhere! Consider: the average person produces 3-4 pounds of trash in a single day; thatís about 21-28 pounds of garbage a week. Just think: a family of four produces 4,368-5,824 pounds of trash in a single year! Thatís a lot of garbage not to think about, so what do we do with all of this refuse? In previous years, garbage was collected and then put into a landfill (the dump). Today these landfills are becoming full, plus they are not environmentally safe. Landfills create dangerous gases (like methane and nitrous oxide) that escape the pits. Also, damage to the ground and to the water supply occur when toxins from the garbage seep into the soil and find their way to groundwater pipes or leak into nearby lakes and streams. Further, plastic and Styrofoam stay virtually intact under the earth forever, while cardboard and paper slowly decompose. The Ogden Martin Systems of Bristol is changing that situation for Bristol, along with 13 other cities in Connecticut. The garbage brought to Ogden Martin is turned into something useful for the Earth.
The process for turning waste into something useful, such as energy or ash, starts at the curbside where garbage is collected by refuse trucks on scheduled days. At Ogden Martin the truck is weighed at a scale-house, located at the entrance to the facility, to determine the amount of waste being processed. The trash is also checked to make sure that it is appropriate for delivery to the facility. These trucks are not supposed to pick up recycleables, but sometimes by accident some recycleables are tossed into regular trashcans, so they have to be removed and taken to another facility outside the plant.
After stopping at the scale-house, the trucks enter the tipping building. There the trucks dump their waste into a storage pit. However, it isnít stored for very long. Almost immediately an overhead crane mixes the trash in the pit and lifts it up onto a feed chute. This feed chute leads to a large furnace where the temperature exceeds 1,800 degrees Fahrenheit. In the furnace the combustion process begins. Hydraulic ram feeders deliver the garbage from the feed chute onto a stoker-grate that is sloped downward; this grate consists of alternate rows of fixed and moving grate-bars. The bars push upward against the natural downward movement of the waste bed. The waste is then burned, producing ash. The bottom ash makes its way to the end of the grate and falls into the water in the Martin Ash Discharger. Then a forced-draft supplies the primary combustion air underneath the grate. After that, the over-fire air is injected through the front and rear walls of the furnace. There the ash is heated once more by a super heater; the energy from this burning ash heats water which converts it to steam which is directed past the blades of a turbine (fan), causing the turbine to rotate. The rotating turbine is connected to an electrical generator that turns and produces electricity. The energy produced is used to run the Ogden Martin plant, with the remainder sold to Northeast Utilities. The residue ash is used for fertilizer to cover landfills.
Ogden Martin Systems of Bristol effectively deals with a product that we cannot continue to live with but, unfortunately, cannot stop producing Ė garbage. It "converts" about 325 tons of waste a day. When burned, the trash loses 90% of its volume, reducing it to just 10% of its original size! This waste-to-energy plant is a healthy alternative to environmentally dangerous landfills. Plus, it is a facility that turns trash to kilowatts, energy that we do need.
NOTE: See TRASH GRAPH which illustrates the volume of garbage we produce.
The Ogden Martin Systems of Bristol. Visitation.