Wastes and how to manage them
Biodegradable waste is broken down by microbes; non-biodegradable waste is not. Landfills, incineration and recycling handle waste, but the 4 R's best cut how much we make.
Biodegradable vs non-biodegradable
Waste is also grouped as municipal (from towns), hazardous (dangerous, including radioactive waste) and biomedical (from hospitals).
Why open garbage is a problem
- As population grows, the waste we make is becoming hard to manage.
- Open dumps are breeding grounds for flies, rats and mosquitoes, which spread disease.
- Rainwater running off garbage heaps pollutes nearby land and water.
- Radioactive waste from nuclear reactions takes a very long time to decay and harms all living things.
Ways of handling waste
| Method | How it works | Example or drawback |
|---|---|---|
| Landfill | Solid waste is dumped and covered in chosen low-lying sites | Used by cities and some villages; needs a lot of land |
| Incineration | Waste is burnt after removing recyclable material; the ash goes to a landfill | Used for biomedical waste in big cities; but it gives off toxic gases |
| Recycling | Waste is processed into a new, useful product | Plastics and paper recycled; town waste turned into manure; rice husk made into wood particle board |
| Biogas | Microbes break down cattle dung (and even human excreta) to give a fuel gas | Gives cooking fuel, and the leftover slurry is good manure |
The 4 R's at home
- Reduce: make less waste in the first place; carry a cloth bag and a refillable water bottle.
- Reuse: use things again, such as glass jars for storage and old cloth as dusters.
- Repair: mend torn clothes, bags and shoes, and fix appliances instead of throwing them away.
- Recycle: give old newspapers, bottles and cans to the kabadiwala so they can be made into new things.
- Keep wet (biodegradable) and dry (non-biodegradable) waste in separate bins, so each can be handled properly.
A steel tiffin, a cloth bag and a refillable water bottle cut plastic waste every day. Many villages turn cattle dung into biogas for cooking, and the slurry left behind is good manure.
1 marks: “Which of these is non-biodegradable: a banana peel, an old newspaper, a used battery?” The used battery.
2 marks: “What is incineration? Give one advantage and one drawback.” Burning waste after removing recyclables. Advantage: reduces bulk and deals with biomedical waste. Drawback: gives off toxic gases that pollute the air.
3 marks: “Name the 4 R's and explain how each one reduces the waste a family produces.” Reduce: buy and use less (cloth bag). Reuse: use items again (jars). Repair: mend instead of discarding (clothes, appliances). Recycle: send paper, glass, cans to be made into new products.
Bio-yes goes back to nature; bio-no stays and harms. Reduce, Reuse, Repair, Recycle: the best waste is the waste never made.