Solid Waste : Eco friendly Management – Maharashtra Board Class 9 Solutions for Science and Technology (English Medium)
- Kitchen waste is known as biodegradable waste.
- Waste is classified as biodegradable and non-biodegradable waste.
- Biomedical waste is infectious in nature.
- Municipal solid waste is classified as wet solid and dry solid waste.
|Food, Garden waste, Wood||Glass, Rubber, Metal, Plastic|
Solid waste is any unwanted or discarded material by human beings.
Domestic, industrial and commercial establishments such as shops, markets of vegetables, fruits and fish, construction material etc. form a large quantity of garbage. Plastic bags, glass, fibres, containers, scrapped vehicles and discarded building materials are some of the non-biodegradable materials which are present in the municipal solid waste.
Chemicals, paint residues, oil, ash, sludge, heavy metals, fibres and glass are the materials present in industrial waste.
The three important ‘R’s in solid waste management are reduce, reuse and recycle.
- Reduce: Generation of waste should be reduced at the source. Example: Use of plastic or paper should be minimal.
- Reuse: Industrial wastes can be reused by proper techniques and processing. Biodegradable materials can be used for composting or notebooks can be made reusing waste paper.
- Recycle: Recycling is using the same materials for making new products. Plastic, glass and metals can be sent to their respective recycling units.
Household methods in solid waste management:
- At the household level, dry and wet solid wastes are separated and stored in separate containers.
- Then these cans are picked up by the garbage van. After that, these are carried by the municipal transport to landfill sites.
- The dry garbage collected at home can be sent to scrap dealers for recycling.
- The wet garbage can also be used for vermicomposting or composting if there is place to carry out these practices.
Waste separation or segregation, composting, vermicomposting, secured landfill and pyrolysis are the scientific methods in municipal solid waste management.
- Waste separation: In this primary stage, dry and wet wastes are separated, stored and later collected for proper use.
- Composting: Decomposition of degradable kitchen waste in small pits in the backyard, garden or terrace is called composting. Good quality manure can be produced by composting leftover food, peels of fruits vegetables etc.
- Vermicomposting: Converting solid waste into manure or compost with the help of earthworms is called vermicomposting. Vermicompost manure is highly nutritious and can be used for agricultural purposes and garden plants.
- Secured landfill: The site has to be two kilometres away from water bodies. It should not come under the forest zone and should be away from human settlements and highways. Clay and plastic liners are placed in landfills before waste is dumped to prevent the leaching of waste.
- Pyrolysis: In this method, the waste is heated to a high temperature to obtain gas and electricity. Semi-combustible waste is burnt in pyrolysis. It is suitable for municipal solid waste management.
- Biomedical waste is collected and transported safely.
- Different coloured containers are used for collecting different types of waste.
- Vehicles used for transport are regularly disinfected.
- The waste is properly segregated, labelled and appropriately treated.
- Most of the municipalities manage disposal of biomedical waste through different franchises.
- Pyrolysis and incinerators are used to reduce hospital waste.
- To prevent the spread of infections, biomedical waste is properly sterilised and disinfected before disposal.
- Vermicomposting is the method for fast decomposition of biodegradable solid waste with the help of earthworms.
- Earthworm species such as Eisenia foetida and Eisenia andrei are used for this method.
- The manure obtained by vermicomposting is highly nutritious.
- Hazardous waste substances are very dangerous for the natural ecosystem and human life.
- Radioactive and pathogenic wastes and chemical and biological explosives are hazardous wastes.
Bioenergy is obtained from biogas, which is manufactured from organic wastes.
Secured land filling:
- Secured land filling is one of the methods of solid waste disposal.
- In this method, clay and plastic liners are used inside landfill pits before the waste is dumped into them.
- The landfill site must be two kilometres away from water bodies, human settlements and highways.
- Pyrolysis is one of the methods of solid waste management.
- In this method, solid and semi-combustible wastes are heated to a very high temperature.
- Gas and electricity are obtained as a by-product in this method.
An incinerator is a device in which industrial, domestic and biomedical wastes are burnt at a very high temperature.