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Where Does the Trash Go?
Unit 5 - Big Idea Technology, by itself, is neither good nor bad, but decisions about the use of products and systems can result in desirable or undesirable consequences.
One Pound of Trash
Americans create a lot of trash. The Environmental Protection Agency
(EPA) estimates that each individual generates about 1.5 tons of solid waste per year -- about 4.5 pounds per person, per day.
If we continue this pattern, we will have each created 90,000 pounds of trash in our lifetime.
Lets Estimate! What is the approximate volume of
this one-pound trash bag? What shape is it closest too? What is the formula for volume for
this shape? Let’s measure and calculate!
How much in your lifetime?
Now, multiply the volume of that one bag times 90,000.
There are 250,000 people living in Howard County. How many pounds of trash will the people in our county produce in your lifetime?
22.5 billion pounds!!!
In this lesson, students will:
Discuss the impacts of “waste materials” on the environment.
Describe how various “waste materials” can be recycled, reused, or re-manufactured into new products.
Describe, analyze and evaluate the impacts that inventions and innovations have had on the environment.
Cite examples of the development and use of technology posing ethical problems.
What do we do with our old tires?
Although today’s tires last for more miles than they did in the past, the number of cars on the road is increasing and the average number of miles driven annually is also increasing.
More miles….. Still more tires
Tire Scrap in The United States
According to the Scrap Tire Management Council, the standard assumption is that waste (also know as scrap) tires are generated at a rate of one tire per person per year.
The population of United States of America is approximately 300 million people.
What Can Be Done? Toss them in the landfill?
Used Tires as Fuel?
Rubber tires have a very high BTU content which makes them a good source of fuel for cogeneration (the joint production of useful heat and electricity) incinerator facilities or other industries that require incinerators, such as paper mills or cement kilns.
What is a BTU?
A BTU is the amount of heat required to change the temperature of one pound of water one degree.
BTU stands for British Thermal Unit – it is a measurement of heat energy
How many BTU’s in a tire?
The BTU of tire rubber is approximately 15,000 per pound, which is higher than some types of coal and about twice as high as garbage. How much heat energy could a 30 pound tire produce?
15,000 X 30450,000 BTU
Used Tires as Fuel! In 2000, approximately 47 percent
of the 273 million scrap tires generated in the United States were burned for fuel.
Whole tires and rough tire chips are used at cement kilns, pulp and paper mills, power plants, waste-to-energy plants and industrial boilers.
Click here to viewThe Envirotire Video
How can they do this?
Not all good news……
Incinerating tires has its downside….
Pollution - Modesto Energy Company tire incinerator in Westley, California.
5800 lbs/hour of tires, generating about 14 megawatts of electricity
Tire Incineration = Toxic Emissions
Is the energy worth all of this?
The facility was found to be emitting conventional air pollutants as follows:
Particulate matter: 44,100 pounds/yearHydrogen chloride and HCl : 1,428 pounds/yearSulfur dioxide: 11,930 pounds/yearOxides of nitrogen (NOx): 57,400 pounds/yearCarbon monoxide: 76,256 pounds/year
Not just tires….. What else needs to be disposed of
eventually? List 3-5 items that are difficult to
dispose of safely.
What do we discard? Make a list of 20 household (and school)
items that are typically thrown into the trash.
Include daily items, occasional items, and rare items.
Examples Daily – kleenex Occasional – apple core Rare – broken plastic toy
Create “Trash” Cards Share and Compare your list with a
neighbor. As a team, write the name of 20
trash items on index cards. (one per card)
Write your initials on the back each card
Turn them in!
Let’s Examine Our Trash
Sort through a pile of “trash cards” and divide them into these 4 categories Can be reused Can be recycled Can be composted Must be sent to the landfill
4/14 Drill - Copy
Composting - the purposeful biodegradation of organic matter, such as yard and food waste. The decomposition is performed by micro-organisms, mostly bacteria
EbD Resources