11-25 Fuel types and uses

APES 2024

Biomass fuel sources

Biomass fuel sources

are easily accessible

Biomass can be

foudn and gathered by hand

Biomass is used in

developing nations for heating and cooking

Biomass examples

wood and peat

Peat

partially decomposed organic matter like ferns and other plants found in wet, acidic ecosystems like bogs

Coal

a solid fuel formed primarily from the remains of trees, ferns, and other plant materials preserved 280 mil - 360 mil yrs ago

3 coal types

• lignite (worst)

• bituminous

• anthracite (best)

Heat, pressure and depth of burial contribute to the development of

the various types of coal

The largest coal reserves are in

the US, Russia, China, and India

Acid drainage

chemical runoff from strip mining enters waterways

Sulfuric acid leaches

metals from rocks due to acid drainage

US regulations require companies to

restore strip-mined land, but complete restoration is impossible

Mountaintop removal removes

tons of rock and soil

Mountaintop removal destroys

immense amounts of habitat and creeks

Loosening of regulations in 2002 allowed companies to

legally dump debris into valleys and rivers regardless of the consequences

Clean coal tech

technologies, equipment, and approaches to remove chemical contaminants while generating electricity from coal

Clean coal tech scrubbers

chemically convert or remove pollutants (removing sulfur dioxide or nitrogen oxides)

Coal that contains lots of water can

be dried

Gasification

coal is converted into cleaner synthesis gas (syngas)

Syngas

can be used to turn a gas or steam turbine

Steps for using coal to produce electricity

1. burning fuel from coal transfers energy to water, which becomes steam

2. chemical reaction between the fuel and oxygen that yields carbon dioxide and water and releases energy

3. kinetic energy contained within the steam is transferred to the blades of a turbine, a large device that resembles a fan

4. energy in the steam turns the turbine, the shaft in the center of the turbine turns the generator

Cogeneration

The use of a fuel to generate electricity and produce heat (AKA combined heat and power)

Cogeneration example

if steam is used for industrial purposes or to heat
buildings it is diverted to turn a turbine first (improves the efficiency to as high as 90%)

Natural gas

decaying remains of plants and animals (mostly marine) buried under layers of rock, converted by pressure into oil (petroleum) and natural gas over time

Mostly methane (CH4)

natural gas

Natural gas forms when

oil is trapped in porous, sedimentary rock under harder impermeable rock, does not let gas escape

Combined cycle

used in natural gas powered plant, uses a steam turbine to generate electricity, a separate turbine is powered by exhaust gases from the natural gas burning, efficiency can be up to 60%

Coal burning power plant efficiency is around

36%

Crude oil (petroleum)

decaying organic matter trapped under rock layers is compressed into oil over time, extracted by drilling a well through the layers and reaching
underground deposit, oil is pumped out under pressure

Crude oil is converted into different products through

fractional distillation

Burned in a furnace and vapor passes into a column
where different hydrocarbons are separated based on their boiling point

crude oil

Lower boiling point at top and

higher at the bottom

Crude oil products

• Petroleum gas

• Gasoline (for cars)

• Naptha (for plastic)

• Jet fuel

• Diesel fuel

• Motor oil

• Bitumen (asphalt for roads)

Oil sands

slow-flowing, viscous deposits of bitumen mixed with sand, water, and clay

Bitumen

A degraded petroleum that forms when petroleum migrates to the surface of Earth and is modified by bacteria

CTL (coal to liquid)

the process of converting solid coal into liquid fuel

Hydrologic fracturing (fracking)

method of oil and gas extraction that uses high pressure fluids to force open existing cracks in rocks deep underground

Allows extraction of natural gas from locations that were difficult to reach – not economically feasible

hydrologic fracturing (fracking)

Hydrologic fracturing (fracking) example

Marcellus Shale, PA, NY

Nonrenewable but not a fossil fuel

nuclear power

Nuclear power

electricity generation uses uranium-235 as a fuel source

Fission

a nuclear reaction in which a neutron strikes a relatively large atomic nucleus, which then splits into two or more parts, releasing additional neutrons and energy in the form of heat

A nuclear power plant uses heat from nuclear fission to boil water, this water produces

the steam to turn the turbine, which turns a generator

Nuclear disaster

• Three Mile Island – no radioactivity released – in Pennsylvania, 1979

• Chernobyl - due to human error, 1986

• Fukushima – due to a tsunami after an earthquake, 2011

Nuclear disasters

Have short and long term impacts on the environment

Nuclear power environmental effects

• Considered cleaner because it does not produce air pollutants

• Does release thermal pollution – raises water temperature too high for organisms – water is put into cooling towers before release

• Less dissolved oxygen in warmer water, more dissolved oxygen in cold water releases radioactive, hazardous solid waste