SOLID WASTES

By:

Dr. (Smt) REKHA DASSecretary

Odisha Bigyan AcademyBHUBANESWAR

SOLID WASTES Unwanted, discarded and left-over garbages

generated from different sources in day to day life, thrown anywhere and any time.

Harmful, toxic, poisonous causing environmental pollution and concern for living organisms including man.

Collection, storage, transfer and transport, processing and disposal should be done with the best principles of public health, economics, engineering, conservation, aesthetics and other environmental considerations.

• Domestic wastes,

• Municipal wastes,

• Commercial wastes,

• Institutional wastes,

• Garbage, Rubbish, Ashes,

• Hazardous wastes,

• Hospital wastes

• Agrowastes

• Radioactive wastes

TYPES OF SOLID WASTESTYPES OF SOLID WASTES

These wastes are generated by household activities such as cooking, cleaning, repairs, redecoration, empty containers, packaging, clothing, old books, newspapers, old furnishings, etc.

Domestic wastes :

Wastes generated due to municipal activities and services such as street waste, dead animals, market waste and abandoned vehicles.

Generally, the term is used in a wider sense to incorporate domestic wastes, institutional wastes and commercial wastes.

Municipal wastes :

Composition Percentage

Biodegradable 52%Metal scrap, Rubber, textiles, etc 11%Stones and Rubber 8%Sand 23%Plastics 10%Paper products 6%

Solid wastes generated in offices, wholesale stores, restaurants, hotels, markets, warehouses and other commercial establishments.

These are further classified into garbage and rubbish.

Commercial wastes :

Wastes generated from institutions such as schools, colleges, hospitals, research institutions. The waste includes garbage, rubbish and hazardous wastes.

Institutional wastes :

It includes animal and vegetable wastes due to various activities like storage, preparation and sale, cooking and serving. These are biodegradable.

Garbage:

Residues from the burning of wood, charcoal and coke for cooking and heating in houses, institutions and industries. Ashes consist of a fine powdery residue, cinders and clinker often mixed with small pieces of metal and glass.

Ashes:

Apart from garbage and ashes, other solid wastes produced in households, commercial establishments, and institutions are termed as rubbish.

Rubbish : :

Hospital WastesHospital waste is generated during the diagnosis, treatment, or immunization of human beings or animals or in research activities in these fields or in the production or testing of biologicals.

It may include wastes like sharps, soiled waste, disposables, anatomical waste, cultures, discarded medicines, chemical wastes, etc.

These are in the form of disposable syringes, swabs, bandages, body fluids, human excreta, etc.

This waste is highly infectious and can be a serious threat to human health if not managed in a scientific and discriminate manner.

It has been roughly estimated that, out of 4 kg of waste generated in a hospital at least 1 kg would be infected.

Industrial and hospital wastes are considered to be hazardous as they may contain toxic substances.

Certain types of household wastes are also hazardous.

Hazardous wastes could be highly toxic to humans, animals, and plants; are corrosive, highly inflammable, or explosive; and react when exposed to certain things e.g. gases.

Hazardous Wastes

Garbage - CategoriesOrganic waste:

kitchen waste, vegetables, flowers, leaves, fruits.Toxic waste:

old medicines, paints, chemicals, bulbs, spray cans, fertilizer and pesticide containers, batteries, shoe polish.

Recyclable:paper, glass, metals, plastics.

Soiled:hospital waste such as cloth soiled with blood and other body fluids.

Segregation of wastesWaste can be segregated as

1. Biodegradable and2. Nonbiodegradable.

Biodegradable waste include organic waste, e.g. kitchen waste, vegetables, fruits, flowers, leaves from the garden, and paper.

Non-biodegradable waste can be further segregated into:a) Recyclable waste – plastics, paper, glass, metal, etc.b) Toxic waste – old medicines, paints, chemicals, bulbs, spray cans, fertilizer and pesticide containers, batteries, shoe polish.c) Soiled – hospital waste such as cloth soiled with blood and other body fluids.

Toxic and soiled wastes must be disposed of with utmost care.

Wet waste, which consists of leftover foodstuff, vegetable peels, etc., should be put in a compost pit and the compost could be used as manure in the garden.

Dry waste consisting of cans, aluminium foils, plastics, metal, glass, and paper could be recycled.

Household waste should be separated daily into different bags for the different categories of waste such as wet and dry waste, which should be disposed of separately.

One should also keep a bin for toxic wastes such as medicines, batteries, dried paint, old bulbs, and dried shoe polish.

Segregation of Domestic wastes

Organic matter constitutes 35%–40% of the municipal solid waste generated in India.

This waste can be recycled by the method of composting, one of the oldest forms of disposal.

It is the natural process of decomposition of organic waste that yields manure or compost, which is very rich in nutrients.

Composting is a biological process in which micro-organisms, mainly fungi and bacteria, convert degradable organic waste into humus like substance.

This finished product, which looks like soil, is high in carbon and nitrogen and is an excellent medium for growing plants.

The process of composting ensures the waste that is produced in the kitchens is not carelessly thrown and left to rot. It recycles the nutrients and returns them to the soil as nutrients.

Composting

Compost allows the soil to retain more plant nutrients over a longer period.

It supplies part of the essential elements needed by the plants.

It helps reduce the adverse effects of excessive alkalinity, acidity, or the excessive use of chemical fertilizer.

It makes soil easier to cultivate.

It helps keep the soil cool in summer and warm in winter.

It aids in preventing soil erosion by keeping the soil covered.

It helps in controlling the growth of weeds in the garden.

Composting: some benefits

Plastics

Plastic with its exclusive qualities of being light yet strong and economical, has invaded every aspect of our day-to-day life.

It has many advantages: it is durable, light, easy to mould, and can be adapted to different user requirements.

Once hailed as a 'wonder material', plastic is now a serious worldwide environmental and health concern, essentially due to its nonbiodegradable nature.

Lack of Dumping-yards and Land-filling space.

Hospital wastes contains pathogens, toxic substances, medical equipments and instruments causing diseases, soil and water pollution.

Industrial wastes cause air, water, soil pollution and contamination of groundwater.

Conventional plastics exhibit Carcinogenic and Teratogenic (embryotoxic) properties.

Dioxin and Furans are highly carcinogenic and toxic by-product of the manufacturing process of plastics.

Problems Associated With Solid Wastes

Reduction : Reduce the generation of unnecessary waste, e.g. carry your own shopping bag when you go to the market

and put all your purchases directly into it. Re-use : Do not throw away the soft drink cans or the bottles; cover them with homemade paper or paint on them and use them as pencil stands or small vases.

Re-cycle : Use shopping bags made of cloth or jute, which can be used over and over. Segregate your waste to make sure that it is collected and taken for recycling. Studies have revealed that 7 -15% of the waste is recycled.

Refuse : Instead of buying new containers from the market, use the ones that are in the house. Refuse to buy new items though you may think they are prettier than the ones you already have.

Four “R”s (Refuse, Reuse, Recycle, Reduce) to be followed for waste management :

AGROCHEMICALS :• To meet the food requirement of rapidly increasing population in India, advanced farm-technology started during 1966-67.•William S. Gaud (1968) coined the term ‘Green Revolution’ to describe the growth in agricultural production.•Crop production is doubled or even tripled by widespread irrigation, use of high yield varieties of cereals and pulses and extensive use of agrochemicals.•Agrochemicals include pesticides and inorganic/chemical fertilisers.•They are not eco-friendly.

PESTICIDES :

Pesticides are hazardous chemicals or toxicants used to suppress or kill pests (pathogens).

Pesticides are classified into several groups

Name Chemicals used Target pests

Insecticides : Organochlorine (DDT, DDD, Aldrin) InsectsOrganophosphate (Parathion, Malathion)Carbamate Compund (Carbaryl/Sevin, Baigon)

Nematocides : Ethylene dibromide, Thionazin, Aldicarb Nematodes

Fungicides : Diethyldithiocarbamate, Captan, Folpet, FungiPenta- and Hexa-chlorobenzene.

Herbicides 2-4 dichlorophenoxy aceticacid Weeds2-4-5 Trichlorophenoxy aceticacid 2-methyl-4-chloro-phynoxy aciticacid (MCPA)Borates, Chlorates and Trizines

PROBLEMS ASSOCIATED WITH THE USE OF PESTICIDES :

Most Pesticides are poisonous and cause soil, air, water pollution Damage and kill microbes, earthworms etc. Residual pesticides washed into water bodies and contaminate groundwater by leaching Use of pesticides for storage of food items, consumed by human beings causes harm to alimentary canal, nervous system, reproductie system, urinary system etc. Pesticides passing through food chain causes bioaccumulation and biomagnification. Eg. 1 kg of soil may contain 0.001 mg of pesticides whereas carrot grown may contain 2-6mg/kg and rabbit eating those carrot may contain 20-35mg/kg. Ex. of bioaccumulationa and biomagnification is the high conc. of DDT in birds which interfere in calcium metabolism, so that egg shell can not be hardened. After several generations pests become pesticide resistant. Pests multiply rapidly- pesticide resurgence. Pesticides like DDT, toxaphene, captan are carcinogenic. Pesticides like carbaryl, folpet, pentachloronitrobenzene are teratogenic (embryo toxic). Pesticides causes mutation. Zinc, lead, cadmium used in spinach and cauliflower causes cramps, nausia, interfere brain development, high blood-pressure and heart diseases.

CHEMICAL FERTILISERS :Plants require macro and micro nutrients•Macro nutrients :

• Primary : N, P, K, • Secondary : Ca, Mg, S

(N – promotes plant growth, P-promote root development , K - retain water in plants)

•Micro nutrients : B, Cl, Cu, Fe, Mn, Mo, Zn, Na, CoEffect of Chemical Fertilisers : Several application of Agrochemicals kill beneficial microbes so that soil turns into a dead heap of silt, clay and sand. Each year the physiological capacity of crop increases, so quality of fertiliser use also increases. Repeated application of chemical fertiliser gradually suppresses natural nutrient regeneration capacity of crop-land. Excess NPK fertilisers declines protein content of corn, maize, wheat , gram etc. Excess use of fertiliser damages roots and leaves become yellow- Fertiliser burn Major portion of fertiliser is lost by leaching, denitrification and volatilization, thus polluting soil, air and water.Deposition of NH3 and SO4 causes acidification of soil. Nitrobactor reduces nitrate to nitrite. Nitrate when absorbed in bloodstream reacts with oxyhaemoglobin to produce methamoglobin and causes methamoglobinemia (blueboby syndrom).High amount of fertiliser accelerates algal growth – eutrophication.

RADIO-ACTIVE WASTES :Radioactive wastes are by-products of nuclear power generation and other applications of nuclear fission or nuclear technoogy.

Comprises a number of radioisotopes which are unstable, emit radiations harmful to men and environment.

Radiations are of two types:

IonisingNon-ionising

Ionising Radition : Radioisotopes able to remove electrons from an atom and attach them to other atom, thus producing +ve & -ve ion pairs.eg X-ray, Y-ray, a-, b- particles.Non-ionising Radiation : Don not cause ionisation. Radio wave, micro wave, infrared, visible light, UV radiation.Half-life : Time required for one half of a given number of atom to decay to another form –

I131- 8 days, C14 – 5568 years, Plutonium 239 – 7,10,100 years, Uranium 235- 704 million years. Long half-life radioisotopes are most dangerous than Low-energy

short-life isotopes.

Laws For Solid Waste

Management• Hazardous waste (Management & Handling) Rules, 1989

• Bio-medical wastes (Management & Handling) Rules, 1998

* Recycled Plastics (Manufacture and Usage) Rules, 1999

* Municipal Waste (Management and Handling) Rules 2000

* Manufacture, storage and Import of Hazardous Chemicals Rules,

1989

* Batteries (Management and Handling) Rules, 2001

“Anything else you’re interested in is not going to happen if you can’t breathe fresh air and drink pure water.

Don’t sit idle, do something. You are by accident of fate alive at an absolutely critical moment in the history of our planet”.

Conclusion

Municipal waste

Door-to-door Collection

Middleman who Recycle

Recycling Industry

Landfill Scavengers

Scraps Collected tobe recycled

Heaps of Scrap tyres

E-waste

Recycling Process of Plastic

Recycling of brass metal

Recycled brass metal