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13. Recycling:

Managementof Solid Waste

OBJECTIVES
> To recall that humans produce many waste materials
> To understand that human wastes may become food for disease vectors
> To appreciate that there are different ways of disposal of human refuse
> To understand the benefits of recyding

Human refuse contains such items as metals, plastic bags, glass, remains of food and ash. This
refuse must not be allowed to accumulate because:
It is inconvenient, and gets in the way of people, their vehicles and their animals.

It is unpleasant to look at.
It could act as a breeding ground for organisms which transmit disease.
To prevent refuse (rubbish) from building up it can be delivered to refuse tips, landfill sites or
incinerators. The refuse disposal sites are normally sited away from residential areas, and
surrounded by fences to stop rubbish blowing away and prevent children from playing in them.
Two alternative ways of disposing of the refuse - incineration and landfil. Each of these
methods has the advantage that it can provide energy, and so reduce our use of fossil fuels.

Recycling

Recycling involves reusing waste products or materials which would otherwise be thrown away.
This includes reusing items in their original form and sending materials away to special centres
where they can be melted down or pulped to act as raw materials in industry.
Items that can be reused include:
glass milk or soft drink bottles
plastic shopping bags
paper that has only been written on one side
clothes
... and materials that can be pulped or melted down include:
glass bottles
aluminium cans

plastic bottles
paper and card
scrap metal.

Plastic bottles can be melted and reused in clothing, for example!

Non-biodegradable plastics cannot be broken down by natural biological processes. They may
accumulate and are a danger to fish, birds and mammals. If they can be collected they may be
recycled.

Learning Module Organisms and Their Environment | Class 11 40