Grapple Crane Loading Garbage into Hopper.jpg​First, the trucks delivering waste are weighed at the scale house and monitored for safety. Once cleared, they enter an enclosed tipping area where they unload waste into a concrete storage pit. An overhead crane mixes the delivered waste (large objects that cannot be processed are removed for landfill disposal). The crane lifts the waste to the furnace hoppers located above the back wall of the pit. Air from the pit and tipping area is used for burning the waste. This prevents the escape of dust and odor from the building. Once in the furnace, the waste travels on moving metal grates. A minimum temperature of 1800 degrees F is used, assuring complete combustion and leaving little chance of releasing unburned pollutants.

Hot gases are carried up from the grate area through several boiler tube sections where heat is absorbed to produce steam. The gases pass from the boiler through a scrubber, where a water mist containing lime is mixed with the gases. The gases are cooled and a chemical reaction of the lime with the gases neutralizes any acids and produces particles that can be collected.

Next in the process line is a baghouse that works like a large vacuum cleaner, collecting particles produced in the boiler and scrubber. The cooled and cleaned gases are vented through a stack flue topping out at 275 feet above the ground.

The entire process is guided and monitored by operators from a central control room. All processing activities take place indoors to control dust odors, and to prevent rain water from coming in contact with either waste or ash. Metals in the ash are removed and recycled while the remaining ash is sent to the landfill.

Steam from the boilers power two turbine generators that produce enough electricity to run the campus plants and operations. The remaining electricity is sold to be used in homes and businesses.

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