Waste can be basically separated in to two main groups.

1.     Biodegradables: waste which has or animal or plant origin that can be broken down by other organisms. For example: food waste, garden waste

Biodegradables can further be subdivided in to two categories as short term biodegradables and long term biodegradables.

Short term biodegradables: eg. Green leaves and food waste. This type of waste can be directed to composting or biogas generation.

Long term biodegradables: coconut shells, king coconut and coconut husks and tree trunks

2.    Non biodegradables: waste that cannot be degraded by other organisms.

For example: plastics, polythene, glass and metal items in waste. These materials can be recycled.

*Papers are biodegradable. But when separating waste paper is categorized under non biodegradables as paper can be recycled.

National color codes for categorizing waste:

1. Biodegradables: Food and kitchen waste, garden waste
2. Paper
3. Plastics
4. Glass
5. Metal and coconut shells

Tips to be considered in separating waste

•    Put only ‘clean’ ‘dry’ plastics, polythene, glass or metal item in to the recycle bins. Shake, scrape or rinse off food residues from the recyclables and shake off the water after rinsing. Do not pack the recyclable tightly.   Allow air-drying where possible

•    Use a minimum amount of water to clean your plastic, polythene, glass or metal. Items

•    Don’t crush waste paper. Flatten and fold before discarding. Flattened paper takes up less space.

• •    Flatten plastic bottles, where possible.
• •    Fold the polythene bags into a triangle before putting them in to the recyclable bin.

i.    Fold the bag in to two along the mid long axis

ii.    Do the same till you get a strip about 1’ wide.

iii.    Fold one corner of the strip like a triangle.(It will result a triangular end)

iv.    Fold the triangular end over the rest

v.    Keep folding till you end up with a triangle.

•    Keep old mobiles or mobile batteries in an envelope and hand over at any Dialog Telecom arcade.

•    Currently we most local authorities do not have facilities to collect and dispose batteries, fluorescent bulbs etc.

Composting is the purposeful aerobic biodegradation of organic matter.  Microorganisms like Aerobic bacteria and fungi metabolize organic material resulting compost.

Major methods of composting in Sri Lanka are barrel method, pit composting, heap composting, jeewa kotuwa. Jeewa kotuwa (live cage), barrel and pit composting methods are practiced at house hold level while most of the local authorities composting their waste do practice heap composting method.

Boigas production: is the production of a gas by anaerobic digestion of organic material. The resultant gas can be used as bio fuel. Dry Batch system, Floating dome and fixed dome methods are the comment used methods of biogas systems in Sri Lanka.