WASTE E8by Mickey MulderGeorge Washington High School

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"According to the World Wildlife Fund's 2006 Living Planet Report, we are now turning resources into waste 25% faster than the Earth can turn waste back into resources“ –John Green

Methods of Waste DisposalLandfill SitesIncinerationRecyclingBurial of Radioactive Waste

LANDFILLS!!!!

A Little About LandfillsWaste is increasing rapidly, so sequentially

landfills compactly is decreasing.Landfills take up land where people, animals

and plants could be growingThey are the most common form of waste

disposal

The ProsWaste is out of sight out of mind

People believe once the garbage has left there home or office it doesn’t effect them….. WRONG!!!

Its easyThat’s It, there are many better alternatives

to landfills including recycling and incineration

The ConsUgly, Stinky, Space consuming, Loads of garbageTransportation costs to landfills are high and tend to

be far away from cities. For example Toronto outsourced their garbage all the way to Michigan.

Underground water and soil pollution can permanently scar the surrounding land as well as the organisms living there

Anaerobic decomposition of organic wastes, such as most foods, plants, and some other garbage can releases the green house gas methane (CH4) as well as ammonia (NH3), Hydrogen Sulfide and others

Medical waste and biological contaminatesMedical Waste also tends to be thrown in landfills,

although not much of this waste can be recycled, some materials can be made from recycled goods which ultimately cuts down on garbage, this includes things like pipette tips, as well as biological storage bags or boxes. Found on http://www.ehs.uci.edu/programs/biosafety/medwasteguide.pdf

Other medical waste includesCHEMO wasteSharpsPharmaceuticalChemical waste

INCINERATION!!!

What’s the deal with incineration?!?!

Incineration is the burning and melting of garbage in order to produce energy and slag

This resulting slag can either be used in construction such as building roads and buildings or be safely discarded in a landfill

Incineration also requires energy to transport waste similar to a landfill, however in the burning process some energy can be recovered

The good, the bad, and the uglyThe Pros The ConsCreates EnergyDoesn’t scar the land

like a landfillCan kill disease causing

microorganismsUses less space, and is

not as unattractive as a landfill

Expensive, and still uses more energy that eat creates

The burning of plastics release dioxins into the environment

Slag doesn’t serve many purposes

RECYCLING!!!

RecyclingRecycling is presently the best way to get rid

of waste. Not only does it reduce green house gasses, conserve energy, and have lower costs, but your neighbors will thank you for it!

The recycling process is divided into four partsGlassMetalsPlasticsPaper Products

Glass-The process1st Glass is separated by colors mainly, clear,

amber, and green, many glass containers for food and drinks fall into these categories. However special composition glass such as mirrors and light bulbs cannot be recycled.

2nd The glass in than crushed, and is now called “cullet.”

3rd The glass is exposed to magnets to remove metal and a vacuum to get rid of paper and plastic.

4th The glass is finally heated to about 1200˚C where it is mixed with sand, limestone, or ash to create new bottles jars and tiles

Glass- The BenefitsReduces costs in mining for new glass such

as mining waste and cost of raw materialsUses only a third the energy to produce as

virgin glassUses only half the water virgin glass doesReduces use of landfillsCullet can be used in constructionGlass can be recycled over and

over again

Metals- The ProcessThe metals must be separated into ferrous

metals and non ferrous metals (I.E. Tin cans separated from Aluminum cans)

1st The Metal is cut up than magnets separate the lighter aluminum metal by flotation.

Next the metals are melted and reused

Metals-The BenefitsConserves raw materialsDramatically reduces energy costs, water

use, and landfill use, therefore less greenhouse gasses

Aluminum and steel, the most common recycled material, can be recycled over and over again! Non ferrous

(left)Ferrous (right)

Plastics

Plastic-The ProcessBecause of the many different types of plastic,

such as polyethene and polystyrene, it is expensive and difficult to recycle plastics.

Hence the numbering system which helps to manually separate similar plastics.

Low density polyethylene (LDPE), polypropylene (PP), polystyrene (PS) can not always be recycled however polyethylene terephthalate (PETE) and high density polyethylene (HDPE) can.

Once similar products are combined they are melted and reused

PETE- polyethylene terephthalate- found in soft drink, water and beer bottles etc.

HDPE- high density polyethylene- found in bleach, milk jugs, juice bottles etc.

V-vinyl- found in PVCLDPE- low density polyethylene-

Squeezable bottles, bread, frozen food, dry cleaning and shopping bags

PP- polypropylene- found in some yogurt containers, syrup bottles and ketchup bottles

PS- polystyrene- found in Disposable plates and cups, meat trays, egg cartons and carry-out containers

Plastics-The BenefitsGreatly reduces landfill sites and use of

incineratorsUses less petrochemicalsUses less energy and water compared to

virgin plasticsThere are many uses for recycled plastics,

from plastic lumber such as Trex to polyester fibers.

Paper

Paper-The ProcessPaper with wax or plastic coatings cannot be recycled

therefore paper must first be separatedPaper is than chopped and mixed with water as well

chemicals such as Calcium Oxide (CaO) and Calcium Carbonate (CaCO3)

This process brakes the paper down and creates pulp.Spinning this pulp than removes heavy objects like

paper clips and staples, the ink is than washed away by adding more water

Other chemicals are used to remove dyes, inks, and glues

Paper-The Process cont.Often fresh pulp is added, if this not treated

to remove lignin, a glue in wood that holds fibers together, the paper will turn yellow in sunlight such as with newspapers

Hydrogen Peroxide (H2O2) or Chlorine Dioxide (ClO2) can also be used to bleach the paper

Paper- The BenefitsOnly needs half the energy and water that

virgin paper needsReduces trees that have to be cut down,

preserving natural forests and saving animal habitats

By saving forests use also reduce greenhouse gasses as CO2 is consumed by plants

Extends life of landfill sites because less trash is there

Note: Paper can only be recycled so many times as the fibers lose strength

Radioactive Waste!!!

What is Radioactive Waste?It all started when the French physicist Henri

Becquerel (1896) accidentally discovered that some isotopes undergo reactions that change the nuclear form

There are three common types of radiationAlphaBetaGamma

Alpha RadiationAn Alpha radiation an alpha particle, a

positively charged helium nuclei.These alpha particles have a low penetrating

power, only about a few centimeters of air and can be stopped by clothing paper and skin.

Beta RadiationBeta radiation occurs in beta decay when a

stream of negatively charged electrons are expelled from an atom

In beta decay, a neuton converts to a proton emitting a beta decay in the process. The beta particle is identical to an ordinary electron.

Beta particles, electrons, can penetrate a few meters of air, this is still only a moderate penetrating power.

Gamma RadiationGamma rays are emitted if a nucleus still has

excess energy following decay and the emission of other particles. They are electomagnetic in nature (called photons), with a discrete, unique energy (this is used to identify different radioisotopes).

Photons are packets of energy, with wave like properties. Photons make up light.

Gamma rays are not physical particles, but their interactions with matter are described by assigning them particle-like properties.

Gamma rays can penetrate 10cms of lead and up to a couple meters of concrete

Radioactive Half livesBecause of decay, all radioactive isotopes,

eventually brake down into other materials, when only half the original substance is left, it has gone though 1 half-life

Half-lives can range from milliseconds to billions of years depending on the element and isotope

To equate half lives use the equation:Original Mass = Remaining

Mass 2^half life

Radioactive Waste DisposalThere are three levels of waste storage,

depending on the type of decay it produces and the length of half life

Low Level WasteMedium or Intermediate WasteHigh-level Waste

Low-Level WasteHolds 90% of nuclear waste, but is only

responsible for about 1% of the radiationCompacted to reduce volume, than buried in

shallow lined land-burial trenches90% of this waste will return to background

radiation within 100 years.This radioactive waste typically has only alpha

and low level beta radiation and short half-livesWaste includes clothes, gloves, paper, products

from nuclear fuel cycle, hospitals and nuclear research facilities

Mid-Level/ Intermediate WasteThis waste is often stored in steel containers

in concrete vaults below groundIntermediate waste is used with intermediate

levels of beta decay, and with intermediate half-lives, shockingly.

This waste is produced from nuclear reactor parts and processing nuclear fuel

High-level WasteVery small percentage of waste but is the biggest

contributor to radiationMust be stored for a very long time, which causes

the most problemsPresently the best solution is to change the liquid

waste into glass, than burying deep underground in earthquake free environments. Such as granite or salt mines.

This waste is normally due to high beta or gamma radiation with a long half-live

High-level waste comes from spent fuel rods, and processing of spent nuclear fuel

The End