Plastic-Recycling

University of Science and Technology Houari Boumediene
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Plastic Recycling
Faculty of Electronics and Computer Science
By:
DIDANE Aziz
and
MOKEDDEM Rafik

I- Introduction:
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• Plastic is among the most popular and important
materials used in the modern world. The basic raw
materials of plastic are petroleum and gas, we can
optimize the lifespan of plastics by recycling and
reusing them.
• Plastic recycling refers to the process of recovering
waste and scrap plastic and reprocessing it into useful
product. But many plastic product is nonbiodegradable,
it's necessary to protect and clean
environment

Cycle of Plastic Recycling
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II- Plastic recycling process:
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• An item made out of plastic is recycled into a
different product, which usually cannot be recycled
again.
• Before any plastic waste is recycled, it needs to go
through different stages

1-Collection:
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• Plastics are available in a
number of forms for example
plastic containers, jars, bottles,
plastic bags, packaging plastic.
Due to their nature and
availability. Tons of scrap
plastic are collected and sent to
a collecting yard where they
are then packed and
transported to plastic
processing plants.
Bottle Balls

2-Sorting:
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• The actual plastic recycling process starts with sorting of the
different plastic items by their resin content and color. There
are specially designed machines that help in sorting of the
plastics according to their resin content.
• The sorting machine will emit in the near infrared, and then
analyze the reflected wave to determine the material. As for
the sorting of the color, it is done by camera

3-Shredding:
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• After sorting the plastics, the next step is to cut the
plastics into pieces. The plastic bottles and containers
are then ground and cut into tiny pieces or flakes. The
heavier and lighter plastic flakes are separated using a
specially designed machine. The separation process
helps in ensuring that the different plastics are not put
together or mixed up in the final product.
Remember that different
plastics are used to make
different items.

4-Cleaning:
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• After a complete separation, the flakes or chunks
are then washed with detergents to remove the
remaining contamination.
• The plastic flakes are then subjected to moderate
heat to dry.
• The company practices quality tests on flakes and
if they are conclusive, they can be stored in silo.

5-Melting:
• The dry flakes are melted down.
They can be melted down and
molded into a new shape or they
are melted down and processed
into granules as shown in the
figure on the right.
• The flakes are introduced into the
extruder and heated therein. The
plastic comes out of the extruder
head in the form of monofilaments
or wires that cool in contact with
the water in the tank. The wires
pass through the die where they
are cut by a rotating blade. This
process provides the correct grain
or granulate required.
Plastics granulate
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III- Advantages of recycling
plastics:
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• Plastics should be recycled because of a number of reasons
as can be seen below:
a)-Burden on the Environment:
Plastic goods are useful because they are durable, but this becomes a
disadvantage when items are discarded. In nature, plastic bits and
pieces become unsightly nuisances and hazards to animals. When
plastics are eliminated through recycling, the environment looks clean
and inhabitable.

)-Provision of a Sustainable
Source of Raw Materials:
Recycling plastics provides a sustainable source of raw materials to the
manufacturing industry. Once the plastics are recycled, they are sent to
industries to be redesigned and converted into new shapes and used in
different appliances.
c)-Consumes Less Energy:
Recycling plastic saves energy. The process of manufacturing plastic using
natural raw materials is expensive and time consuming compared to the
recycling process.
d)-Reduces Landfill Problems:
Recycling plastics minimizes the amount of plastic being taken to the
ever diminishing landfill sites.
Most countries have designated areas specifically meant for burying
plastics. When they are recycled, these sites will receive little plastic
garbage. The remaining areas can be used for other purposes.
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IV- Conclusion:
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In conclusion, plastic industries offer considerable
benefits for the future, but it is evident that our current
approaches to production, use and disposal are not
sustainable and present concerns for wildlife and human
health.
We have considerable knowledge about many of the
environmental hazards, and information on human health
effects is growing, but many concerns and uncertainties
remain. There are solutions, but these can only be
achieved by combined actions.

Thank you for your attention!
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