Seattle Waste-to-Energy Facility

Reducing the amount of trash disposed off in oceans and landfills is necessary in today’s increasingly crowded and wasteful world.

Building a waste-to-energy plant near the city of Seattle would provide a solution for reducing the amount of trash Seattle sends to Oregon. Furthermore, designing the facility with improved technology found in Denmark, the WTE facility will have fewer emissions than facilities that burn coal, oil, or LFGTE (landfill gas-to-energy).

The WTE facility will reduce landfills and generate green energy benefitting society and minimally impacting the environment.

Team Five: Joon Jung, Thomas Horst, Yamir Godil, Lucas James, Jacob Aylesworth

Numerous countries around the world use waste-to-energy facilities (WTE) to reduce their dependency on landfills while generating heat and power. A few of the countries include: Denmark, Germany, Netherlands, Norway, Sweden, Russia, Ukraine, China, Taiwan, Egypt, and Japan.

Europe has over 400 WTE facilities. Denmark, Germany, and the Netherlands have been leading Europe in turning waste into energy; they also have high recycling rates. Denmark has been using WTE facilities for over 100 years and was the first country in the world to ban the disposal of burnable materials in landfills.

The percentages for material disposal in Horsholm, Denmark, are as follows: 61% recycled, 34% incinerated, 4% landfill, 1% special disposal. The New York Times, in April 2010, mentioned, the plant in Horsholm was considered a ‘respected neighbor, producing no noticeable odors.’

WTE facilities are used throughout the world to manage the landfill challenge. No new WTE facility plants have been produced in the U.S. in over 15 years. It is time for the U.S. to re-evaluate.

Figure 5. Waste-to-Energy Facility on the Isle of Man between Great Britain and Ireland. Courtesy of Ramboll Group.

The world’s global trash production is increasing at a tremendous rate. The industrial revolution has brought forward new mechanical, chemical and other products which post-use are difficult to dispose. Most of the trash that is produced by mankind is either disposed off in oceans or landfills. The process of dumping trash is expensive and has numerous drawbacks.

The Pacific Ocean holds the largest garbage dump in the world and sometimes is referred to as the eighth continent. It is of the size of Texas and extends 100 feet below the surface level. Many biologists estimate millions of birds and marine species have died from poisoning after mistakenly ingesting pieces of plastic from the dump when looking for food.

Landfills are also used to dispose of trash. However, landfills pollute the local environment by contaminating soil and groundwater, generating greenhouse gases, and promoting disease spreading agents such as rats, flies and mosquitoes. Landfills also affect the economy of the city by reducing land values, and creating a negative environment for the society. Lastly, they cause an array of health problems as they emit harmful gases that cause cancer, affect the nervous system, and cause other diseases..

World Trash Problem

Why is Burning Trash Green?

What is a Waste-to-Energy Facility (WTE)?

Figure 1. Comparison of carbon dioxide equivalents for waste-to-energy facility (WTE) and conventional electricity-generating technologies.

Figure 2. Comparison of nitrogen oxide emissions for waste-to-energy facility (WTE) and conventional electricity-generating technologies

Figure 3. Comparison of sulfur oxide emissions for waste-to-energy facility (WTE) and conventional electricity-generating technologies

A waste-to-energy facility reduces the volume of trash entering a landfill and generates electricity by incineration.

The filtering systems implemented in newer WTE facilities clean the air more effectively than conventional electricity-generating technologies. The processes are similar to regular fossil fuel filters. As shown in figures below, WTE facilities have a higher efficiency in reducing emissions such as CO2e , NOx, and SOx.

Garbage will be picked up the same as always and burned in our plant. There is 350,000 tones of trash made in Seattle that we can use to generate approximately 20 MW of electrical power.

How much of waste did Seattle produce in 2009?350,000 tons of trash (excluding recyclables) 1000 pounds of trash per person

How much electricity will be generated and sold?34 MW generated 21 MW to be sold 21MW equivalent to running 20,000 Seattle homes

Volume reduction by incineration?75 to 90% reductionOne ton of waste reduces to about one square foot

Polychlorinated dibenzo-dioxins and furans (PCDD/F) cause human health problems. The plant uses a felt layer filled with a catalyst developed by Gore that destroys PCCD/F. The system can reduce PCDD/F emissions at incineration plants to 0.065 ng/Nm3, far below the regulatory limit of 0.1ng/Nm3.

Dioxins and FuransSOx ScrubberSOx refers to sulfur oxide gasses emitted when fuels containing sulfur are burned. Sulfur oxides in the atmosphere are the primary cause of acid rain. By adding lime (CaCO3) a chemical reaction is induced that causes the Sulfur to be captured in a solid by product CaSO4 (Gypsum), which is then disposed of.

DeNOxNOx refers to nitrogen oxides that are formed in some amount in all high temperature combustion. Nitrogen oxides cause smog and other atmospheric effects. The DeNOx system catalyzes a reaction in the gasses and they are then absorbed by a chemical filter.

Electrostatic PrecipitatorThe ESP removes dust

particles from the exhaust by electrically charging the particles, which are then attracted to a charged plate. The dust is later discharged, shaken off the plates, and disposed of. There are household air filters sold that work on the same principle.

WTE Emission Comparison to Other Technologies NOX Emissions SOX Emissions CO2 Equivalent Emissions

Graphs published in: P. Ozge Kaplan; Joseph DeCarolis; Susan Thorneloe; Environ. Sci. Technol.  2009, 43, 1711-1717

Canoeing through waste.

1. Collect

2. Shred

3.Incinerate

4.Filter

5. Electricity

World WTE

Filtering Technology Conclusion

Seattle WTE Predictions