Transcript Recycling - 新會商會中學 San Wui Commercial Society

Recycling
Every day we damp a lot of domestic,
industrial & agricultural wastes. Some of
the materials in the rubbish will decay:
this include the left-over food, fruit
peelings, etc. They can be broken down
into simple inorganic materials by the
action of bacteria and fungi. We call this
sort of pollutant biodegradable. Other
kinds of rubbish will not decay, because
they are made of substances which
cannot be broken down into simple
inorganic materials. They are called nonbiodegradable. They include plastic,
polystyrene, metal, etc.
This kind of rubbish wastes a
large space of the landfill site and
cannot burn. But we may use
another method to treat with this
kind of rubbish, which is called
recycling. By recycling, we can
make use of used materials like
paper, metal products and plastic
products from the waste again.
For example, we can collect and
melt used glass and metals for the
production of new glass bottles
and new aluminum cans.
Type of rubbish can be recycle
timber products
(e.g. furniture)
paper
metal products
aluminium can
plastics (e.g. tires,
plastic bottles, etc)
Aim of recycling
Save resources
Timber, metal and plastic are non-renewable
resources. Recycling can help to reduce the
using the left materials.
Reduce deposal waste
As part of the rubbish are taken to recycle. Thus
reduce the area of landfill site use.
Protect the environment
As it prevent the burning of plastic in incinerator
and reduce the area of landfill site use.
The fact in Hong Kong of recycling
About 1.94 million tones of waste were
recovered in Hong Kong in 2001. This
represented about 36% of the total waste arising
in the city. The recovered wastes were either
recycled locally (0.17 million tonnes1) or
exported to the Mainland and other countries for
recycling (1.77 million tonnes2).
The major kinds of recyclable wastes recovered
included paper, plastics and metal, which
accounted for about 98% of the waste recovered.
The remaining 2% were glass, wood, rubber
tires and textile.
The fact of paper recycling
The paper recycling process starts by
beating waste paper into pieces in a
stirring tank to generate paper pulp.
Contaminants are removed while the
remaining fibers are fed into fiber refiners
to produce refined fibers. The flowing
refined pulp is then directed to a paper
former for layer deposition. The paper
layer is de-watered by a mechanical press,
followed by vacuum suction and thermal
drying to produce corrugated medium for
paper container and paperboard.
The recycled paper produced by local
recyclers confines to corrugated paper and
duplex paper card for packaging. A variety
of waste paper including the high value
waste paper (e.g. white paper and
computer printout), old corrugated
cardboard, newspapers and other mixed
paper, are being exported to overseas
countries for recycling.
About 800,000 tones of waste paper were
recovered in Hong Kong. This represented
about 58% of the waste paper generated
(dry weight).
The fact of plastic recycling
The recycling of plastic waste is limited to
clean scraps and rejects from
manufacturing sources. Though domestic
recovery of plastic bottles has increased
significantly since the introduction of the
waste separation bins in housing estates
and public places, there is still limited
reprocessing of post-consumer plastic
such as plastic bottles and plastic bags
due to many practical constraints and
barriers.
Most local plastic recyclers consume only
clean and homogeneous pre-consumer
plastic waste collected from the industrial
sector. The plastic waste recycling process
starts with the sorting by resin types. The
plastics are rinsed to remove
contaminants. The sorted and washed
waste is then crushed and mixed with
colourant before melting and pelletising.
The pellets produced will be sold to plastic
product manufacturers as raw material.
The fact of metal recycling
Waste metals are broadly classified into
two types: ferrous and non-ferrous metal.
The most common ferrous metals
recovered in Hong Kong are: -iron
-tinplate -alloy steel scrap -other scrap
Non-ferrous metals recovered include:
-copper & alloys -zinc -nickel -tin
-aluminium -precious metal -lead -metal
ash & residues
About 803,000 tones of ferrous metal were
recovered. This represented about 91% of
the ferrous metal waste arising in the
territory. The major kinds of ferrous metals
recovered included structural steel, scrap
vehicle and scrap home appliances.
About 76% of the total non-ferrous metal
arising was recovered. Out of the 76,800
tones recovered.
The recovered metal is first classified, melt
and then turn to it shape by molding.
The limiting factor of recycling
Although the environmental awareness of the
general public has increased significantly in
recent years, their willingness to actively
participate in waste reduction still needs to be
enhanced.
Promoting waste avoidance on purely
environmental reasons may not be sufficient.
As costs for collection and disposal services
are not linked directly with the quantity of
wastes generated through charging, there is
no financial incentive for waste producers to
reduce waste.
The built environment inhibits recycling
activities from the domestic waste stream.
Small flat sizes restrict source separation
and storage practices.
Low values, high transportation cost or
lack of market demand for recovered
materials particularly for plastics, glass,
paper, metal, textiles, tires and organic
materials.
The predominance of small and medium
recovery and recycling enterprises
discourages investments in waste
recovery technologies.
On Government level,
Provide more Waste Separation Bins at each
buildings, plazas, leisure and cultural venues,
schools, country parks, offices & factories.
Encourages materials re-use, recovery and
recycling to help achieve waste reduction.
Allocating suitable land solely for recycling
purpose at affordable rent is a major measure
for supporting the waste recycling industry. As
the profit of waste recovery and recycling is
often marginal, leasing land through open
tendering exclusively to waste recyclers could
lower their operation cost. This would help
promote the local recycling activity in Hong
Kong.
Organise more activities which are promoting
the recycling and reusing of useful rubbish.
Set up a recycling fund scheme for the
recycling factories, and for organising
recycling activities.
On personal level,
Collect & classify the rubbish like
aluminium can and paper which can be
recycle or reuse. Put these kind of rubbish
into the Waste Separation Bins.
Use both side of paper.
Reduce the using of products made by
plastic (e.g. plastic bag or bottle), always
reuse and put into the Waste Separation
Bins.
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