Chapter 19 Coal

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energy return on energy investment (EROEI)

(net energy) a metric that allows us to compare the amount of energy we get from any individual source to the amount we must expend to obtain, process, and ship it

How much coal does the US use in a year

1 billion tons

How much coal does is take to generate 1 kilowatt hour of electricity

1 pound

The US has __ times more coal than oil and natural gas combined

10

Subsurface mines also account for ___ of all methane release in the United States

10%

At current rates of usage, proven coal reserves should last about

120 years but longer if deeper reserves can be accessed

The United States has __ of the world's coal reserves, with much of its best, low-sulfur bituminous coal found in Appalachia.

28%

Environmental impact statement

A document outlining the positive and negative impacts of any proposed environmental action (including alternative actions or taking no action); used to help decide whether or notthat action will be approved.

What was majority of the coal used for

American households and businesses

Health impacts of coal

Birth defects Black lung disease

What causes more deaths than mining accidents amoungst miners

Black lung disease(breathing coal dust)

Which fossil fuel produces the most air pollution?

Coal

Fossil fuels include

Coal, petroleum and natural gas

Alterations of nutrient cycle due to coal minging

Extra sulfates, released from blasted rock, have increased nitrogen and phosphorus availability, and in so doing have led to eutrophication microbes transform sulfate into hydrogen sulfide, which is toxic to many aquatic plant species.

Where does most of our energy come from

Fossil Fuels

Coal

Fossil fuel formed when plant material is buried in oxygen-poor conditions and subjected to high heat and pressure over a long period of time

2 most common causes of mine explosions

Methanegas fumes and coal dust

Fossilfuel

Non renewable carbon based resources that were formed over millions of years ago

carbon capture and sequestration

Removing carbon from fuel combustion emissions or other sources and preventing its release into the atmosphere.

Surface mining

Removing dirt and rock that overlays a mineral deposit close to the surface in order to access that deposit.

Advantages for using coal

Safer to ship, cheaper to extract, and the US is more abundant of it

Dangerous toxin found in streams downhill from mining operations

Selenium

Subsurface mines

Sites where tunnels are dug underground to access mineral resources.

______ are among the most controversial features of the landscape created by mountaintop removal

Slurry impoundments—reservoirs of thick black sludge that accompany each mining operation

Mountain top removal

Surface mining technique that uses explosives to blast away the top of a mountain to expose the coal seam underneath; the waste rock and rubble is deposited in a nearby valley

Energy

The capacity to do work

Overburden

The rock and dirt removed to uncover a mineral deposit during surface mining.

Acid mine draining

Water flowing past exposed rock in mines that leaches out sulfates. These sulfates react with the water and oxygen to form acids (low-pH solutions).

Challenges to subsurface mining

Water seeps easily into tunnels, and as it does, toxins leech from the surrounding rocks into the gathering pools,

Strip mining

Workers use heavy equipment to remove and set aside overburden so that they can harvest the coal beneath. When they finish mining one strip of land, they return the overburden to the open pit and move on to a new strip.

The US's leading coal producer in 2010

Wyoming, then Appalachia

Strip mines are used in areas like

Wyoming, where the coal is close to the surface and the ground above is fairly level.

What is peat

a soft mash of partially decayed vegetation

Coal has a EROEI of

about 8:1 (8 units of energy produced for every 1 unit consumed for a net production of 7),

More than 40% of electricity generation worldwide, and 45% in the United States, comes from

burning coal

How do co fired power plants work

by feeding pulverized coal into a furnace to generate heat, which then powers a system that produces electricity.

The next big challenge is

carbon capture and sequestration

Another emerging clean coal technology involves

chemically removing some of coal's contaminants before burning it

Potential solution for coal mining

clean coal technology—technology that minimizes the amount of pollution produced by coal

Surface mining techinques are used when

coal seams are close to the surface

Ways to us less coal

design and use more energy-efficient appliances reduce our coal consumption through simple conservation efforts like turning off lights and electronics when we're not using them

Coal-fired power plants also generate tons of

fine ashen particles made up mostly of silica

Toxins released from coal that threaten human health

gases (sulfur dioxide, carbon monoxide, nitrogen oxide, and planet-warming carbon dioxide), radioactive material (uranium and thorium), and particulate matter (soot)

Disadvantages to this process is

it requires energy (thus lowering coal's EROEI) and generates hazardous waste (from the toxins found in the coal)

the U.S. Surface Mining Control and Reclamation Act,

mandated that areas that have been surface mined for coal be "reclaimed" once the mine closes

To get coal beneath peaks

miners began by clear-cutting the forest then drilled holes deep into the side of the mountain set dynamite in those holes, and blasted as much as 1,000 feet of mountain into a mass of rubble known as overburden

Electricity

natural form of energy (lightning and nerve impulses are electrical) that we have learned to create on demand, producing it in a central location and sending it out via transmission lines to where we want it to go.

Effect of this process

obliterated the forest habitat, buried countless streams, and permanently reordered the land's natural contours.

How coal is formed

over long periods of time as plant matter is buried in an oxygen-poor environment and subjected to high heat and pressure

Methane

potent greengas

The EPA's new Mercury and Air Toxic standards will

regulate a limit to how much these toxic air emissions power plants could release

Reclamation

requires that the area be returned to a state close to its pre-mining condition

As the layers of minable coal have grown thinner and harder to reach

the coal industry has become both more sophisticated and more destructive in its approach to extracting the coal.

Environmental costs of coal

the destruction of Appalachia, the pollution of Earth's atmosphere with CO2 and other greenhouse gases.

How were Appalachian coal beds established

the gradual accretion of decomposing swamp vegetation compressed and baked by heat and time they were buried under a mud so thick it kept oxygen out Instead of being fully decomposed by bacteria, their remains produced peat more and more layers of sediment were laid down over the peat, pressure and heat compressed it into the denser rocklike material that we know as coal

Federal law requires that after ceasing operations

the land used for surface coal mines must be restored to close to its original state

Advantage to subsurface mining

they don't disrupt or permanently alter large surface areas Employ more people

What is the vast majority of coal used for

to generate energy

The EPA would register ____as one of the worst environmental disasters in the eastern United States' history

toxic sludge into the Big Sandy River of Martin County, Kentucky

closed mines

where all the coal has been harvested


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