Wheelabrator Concord

Trash being dropped off

On Friday we took a class trip to the Wheelabrator Technologies Inc. Incinerator in Concord, NH. While the tour was not as informative as I had hoped it would be we got to wear cool hard hats and see the incinerator in action. Our tour guild Rob seams like a really nice guy just not the brightest bulb in the bunch. He was a shift superviser and has been working at the incinerator for 10 years. As a shift superviser he is in charge of 20 people durring day time operations and 4 durring night. Rob told us that his"favorite part of the job was the people he works with," but he also enjoys the science behind turning garbage into power.

The crane

Generator

Our tour started in a conference room where we watched a movie that took us through the operations of the incinerator. Wheelabrator opened its first plant in 1985 and since then has opened many more slowly perfecting the proces of clean energy production. The process starts when a truck arrives at the plant it is weighed and then drops its load in the receiving building where it is sorted and stacked to be put into the incinerator, all of this happens on the tipping floor. The trash is then picked up by giant crains and dumped into hoppers that feed the waist into the furness where "it burns on reciprocating grates." There is air flow above and below the trash so that it burns and turns completely to ash. The ash is then filtered out of the furness and brought to a mono fill in Franklin.

The furness

Adding powdered carbon

Scrubber

The hot air that is given off from the burring trash rises up to a boiler thought boiler tubes, the steam that is hight pressure that is produced in this process is then used to run a generator. The steam is then condensed and sent back to the boiler. After the heat is taken out of the hot air it is sent off to be cleaned. The first step in the cleaning process is the adding of powdered carbon to remove harmfull chemicals from the air such as  mercury and dioxins. The the air is sent through the scrubber, where lime and water is sprayed into the air to get rid of pollutants, this is like the shower and then the air must but dried in the bag house. The bag house is full of fabric filters that remove all the little stuff from the air. From the bag house the air goes up and out the stack but the out going air is always monitored.

Bag House

The Concord incinerator has been in operation since 1989 and runs 24 hours a day 7 days a week. They burn 500 tons a day. The web site says that they reduce this by 90% but Rob told us that 200 tons of ash go to the land fill each day witch is not a 90% reduction. The generator produces 14(Rob) or 15(web site) megawatts of power, witch powers 17,000 homes in the concord area.

While at the incinerator the most important things I learned were that the claw games in movie theaters are a scam and being a crane operator at an incinerator dose not increase your chances and the tipping floor would be an amazing place for an action sequence, I did get a good visual on how an incinerator works witch was good, it is always nice to put a visual to the ideas we learn about in class. All in all I thought that the field trip was good and lots of fun, although a slightly more informed guild would have been nice.

Photos and information from www.wheelabratortechnologies.com