This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Part a: Fossil Fuels and Products of Combustion Dependency on Fossil fuels is high and likely to increase in the next two decades Fuels were formed over millions years by compression of organic material (plant and animal sources) prevented from decay and buried in the ground o Coal o Natural gas o Petroleum Hydrocarbons comprised primarily of the following elements: carbon and hydrogen with some sulfur, nitrogen, oxygen, and mineral matter o Composition and amounts of these elements change for different fossil fuels Ex. More hydrogen in liquid fuels than in coal per unit mass Natural Gas: carbon, hydrogen, nitrogen, sulfur, oxygen Petroleum: carbon, hydrogen, nitrogen, sulfur, oxygen, minerals Coal: carbon, hydrogen, nitrogen, sulfur, oxygen, minerals Combustion: rapid oxidation of the fossil fuels elements resulting in the generation of heat o When elements oxidize or combine with oxygen, products of combustion are formed o Some fuel (hydrocarbon) may not completely burn during combustion and therefore is released into the atmostphere along with he products Primary pollutants: carbon monoxide (CO), carbon dioxide (CO2), sulfur (SO2), nitrogen dioxide (NOx), nitric oxide (N2O), volatile organic compounds (VOCs) and hydrocarbons (HCs) Particulate Matter: course particles (PM10), fine particles (PM2.5), ammonia (NH3) o 6 products of combustion: Carbon Dioxide: principal product (accounts for 60-90% of the mass of fuels we burn) The united states continues to be the largest single emitter of fossil fuel- related CO2 emissions reaching an all-time high of 5,912 million metric tons of carbon in 2004 o Transportation: 33%, Industrial: 29%, Residential: 21%, and Commercial: 17% United States: 22%, Germany: 3 %, UK: 2%, India: 4%, China18%, Russia: ^%, Japan: 5%, Canada: 2%, Rest of World: 38% Carbon Monoxide: colorless, odorless gas that is formed when carbon in fuel is not burned completely; component of motor vehicle exhaust Sources: on road vehicles, non road vehicles and engines, industrial processes, fuel consumpion Highest levels of CO in the outside air typically occur during the colder months of the year when inversion conditions are more frequent o Inversion: an atmospheric condition that occurs when the air pollutants are trapped near the ground beneath a layer of warm air Sulfur Dioxide: dissolves easily in water; prevalent in raw materials including crude oil, coal, and ores that contain common metals, such as aluminum, copper, zinc, lead, and iron. Formed when fuel containing sulfur, such as coal and oil, is burned and when gasoline is extracted from oil, or metals are extracted from ore....
View Full Document
- Spring '07