Waste Management PDF

WASTE MANAGEMENT Waste - any substance which is discarded after primary use or is worthless, defective and of no use. SOURCES OF WASTE Depending on their source of origin, wastes are classified into the following broad categories: 1. DOMESTIC WASTE Wastes generated due to domestic activities are ca...

WASTE MANAGEMENT Waste - any substance which is discarded after primary use or is worthless, defective and of no use. SOURCES OF WASTE Depending on their source of origin, wastes are classified into the following broad categories: 1. DOMESTIC WASTE Wastes generated due to domestic activities are called domestic wastes. Food leftovers, fruits and vegetable peels, bits of paper, packets, polythene bags, bottles, empty metal and aluminium cans, scrap metals, glass pieces, cotton, rags, discarded clothes, ashes from burning coal, sewage from toilets, batteries, expired medicines, chemicals, etc., are some of the examples of domestic wastes. 2. INDUSTRIAL WASTE Wastes from various types of small and large scale industries are called industrial wastes. Industrial wastes include any material that is rendered useless during or left over in a manufacturing process. Industry uses a great deal of energy that produces waste gases and other materials. Sulphur dioxide, nitrogen oxides emitted from power stations cause health hazards because of their link with acid rain. 3. AGRICULTURAL WASTE Agricultural wastes mainly include crop residue, husks and straws, wood waste, sawdust, molasses, tobacco waste, coconut waste products, rubber waste, nut shells, fruit and vegetable peels, manure, etc. Most of the agricultural wastes are recycled, used for Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu gobar gas and as manure. Agricultural wastes can cause environmental problems, if they are not disposed of properly. 4. COMMERCIAL WASTE Wastes from commercial houses, stores, godowns, hospitals and offices are known as commercial wastes. These wastes contain waste paper, torn out gunny bags, waste packing materials like straw, broken crockery, glasses, food wastes, packing materials, wood pieces and cans. Hospital waste comprises syringes, needles, plastic bottles, bandage, gloves and dead human tissues. 5. CONSTRUCTION WASTE Wastes generated at construction sites, mainly due to demolition and construction rubble is called construction waste. It includes bricks, pipes, plastic, roofing, and insulating materials, asbestos pieces, etc. 6. MINING WASTE Wastes generated during mining operations, excavations, etc. are called mining wastes. They include tailings, slag heaps, debris, etc. Some mining processes use large volumes of chemicals or liquids, which add to the waste generated. These can be toxic or hazardous. 7. ELECTRONIC WASTE OR E-WASTE Electronic waste refers to various forms of electric and electronic equipment that have ceased to be of any value to its users because they have exhausted their utility value due to redundancy, replacement or breakage. These include refrigerators, televisions, washing machines, microwaves, computers and mobile phones. 8. TOXIC AND NON-TOXIC WASTE Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu Certain wastes are classified as toxic wastes because they pose a serious threat to human health and the environment. These wastes result from industrial processes and products. They also include chemicals used in modern agriculture and medical waste from hospitals. The use of chemicals has increased causing health hazards to living beings. SPOILAGE OF LANDSCAPE Spoilage of landscape refers to the accumulation of heaps of garbage and waste that is simply dumped onto vacant land and left to decompose. Open dumps not only ruin the natural beauty of the land but also provide a home to rats and other disease carrying organisms. Both open dumps and landfills may contain poisonous substances that seep into the groundwater or flow into streams and lakes. POLLUTION The word 'pollute' means to degrade or to contaminate. Pollution is thus, an unfavourable modification of the natural world caused entirely or partly due to direct or indirect actions of human beings. Pollution is caused by human activities like addition of toxic chemicals through the atmosphere into the biosphere. WASTE ACCUMULATION AND GLOBAL PROBLEMS The problem with waste is that it remains in our environment. We move waste from one place to another but never get rid of it completely. Nature has recycled waste materials for millions of years. However, human population has increased so rapidly during the last century that the environment is now threatened by our activities and the wastes they produce. Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu Global Warming: When organic waste decomposes, carbondioxide and methane gas is produced. Both carbon dioxide and methane are Greenhouse gases, which contribute to global warming and climate change. The rate of absorption of solar radiation by earth and its emission back into space as infrared waves balances the heat on the earth. The carbon dioxide and other gases form a blanket around the globe which prevents the passage of infrared waves from the earth back into space. Effects of Global Warming: 1. Global temperature is likely to rise by 2°C to 5°C during the next century. 2. Due to rise in temperature by 2°C to 5°C, there is a chance of melting of ice caps on the Earth's poles. This melting of ice will result in the rise of the sea level. 3. Due to an increase in temperature there will be serious climatic changes. This will bring various changes in wind and rain pattern. 4. Higher temperature will cause rise in transpiration, which in turn, will affect the groundwater table. 5. Insects and pests will increase in the warmer climatic conditions. Thus, pathogenic diseases will multiply. Ozone Layer Depletion In the second layer of the atmosphere, i.e., the Stratosphere which lies at the height of 20 km to 50 km from the Earth's surface, lies the Ozone layer. In spite of its low density, the Ozone layer plays an important role in our life. Due to the presence of Ozone layer, ultraviolet rays and infrared rays from the sun cannot reach Earth directly. Ozone layer absorbs the harmful ultraviolet rays from the sun and protects the life on Earth from their harmful effects. Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu ACID RAIN Acid Rain means the presence of excessive acids in rainwater. Burning of coal, wood or petroleum produce sulphur and nitrogen. These two react with oxygen and are converted into their respective oxides-sulphur dioxide and nitrogen dioxide, which are soluble in water. During rain, these oxides react with large quantities of water vapour in the atmosphere to form acids like sulphuric acid, sulphurous acid, nitric acid and nitrous acid. EFFECTS OF ACID RAIN (i) Acid rain increases acidity in the soil and destroys forests and crops. (ii) It corrodes buildings, monuments, statues, bridges, fences and railings. For example, acid rain produced by the pollutants from the Mathura oil refinery has been turning the white marble surface of the Taj Mahal into yellow. (iii) It poses a serious threat to human health, since it contaminates air and water. (iv) It affects the human nervous system by causing neurological diseases. (v) Aquatic species are affected due to acid rain. (vi) Acid rain affects the plant growth. Plant leaves get burnt and dry. HEALTH HAZARDS SPREAD OF DISEASE THROUGH CONTAMINATION Several incidents around the world have demonstrated the potential harm of accumulation of waste on human health. Waste that is not properly managed is a serious health hazard. Unattended waste dumped in the open attracts flies, rats and other creatures that act Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu as vectors of the diseases and spread them among human beings. Domestic waste poses a serious threat since it is organic in nature, it undergoes fermentation and creates conditions favourable for the survival and growth of pathogens. EFFECT ON TERRESTRIAL LIFE Terrestrial life includes all the organisms that live on land - human beings, plants and animals. Effect on Human Beings: Accumulation of solid waste looks ugly, smells foul, attracts insects, rats and other animals that spread diseases. Burning of waste in the open dumpyards causes smoke and foul smelling air. In addition, rainwater can drain through refuse and carry harmful substances to different places. Sanitary landfills are not fit for human settlements because methane and carbon dioxide gases are released in the first two years. These gases are produced when solid wastes start decomposing underground. Effect on Plants: Waste accumulation has dangerous effect on plant life. Plant life is affected either by direct deposition of harmful toxins from wastes or indirectly through soil. The toxins cause: (i) different types of leaf injuries. (ii) premature leaf fall. (iii) decrease in transpiration. (iv) reduction in the rate of photosynthesis. (v) reduction in biological nitrogen fixation. Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu (vi) dust deposited on leaves block the stomata of plants. These decrease the rate of transpiration and inhibit the absorption of nutrients from soil. (vii) smoke emitted by burning of waste causes reduction in root and shoot lengths, number of leaves and number of grains per spike in case of crops like wheat. Effect on Animals and Birds: Scavangers and stray animals like dogs, rats, pigs and cows are directly affected by waste when they feed on the waste for food. Sometimes these animals consume toxins or non-degradable substances like plastic carry bags present in the waste and die due to choking. The wastes consumed by animals also lead to many diseases and other problems. For example, according to a study, mice that were fed on high levels of toxins had difficulty in reproducing and so did their offspring. EFFECT ON AQUATIC LIFE Waste accumulation can cause significant damage to aquatic life, both fresh water and marine. Two categories of waste that cause greatest damage to aquatic life are - pesticides, which run off agricultural lands and industrial and domestic wastes that are improperly disposed of into water bodies, Over one million marine animals including mammals, turtles, fish, sharks, etc. are killed each year due to plastic debris in the oceans. Biomagnification: The term Biomagnification means increasing the concentration of various toxic substances along the food chain. Toxic substances at the level of primary producers get concentrated at each trophic level as they move up the food chain. The phenomenon of concentrated toxic deposition at the higher trophic level is known as bio-accumulation. A small amount of toxic constituent which is neither excreted nor metabolised, gets Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu increased as the food chain moves upward from one trophic level to the next and the toxic constituents become concentrated. SEGREGATION 'Segregation of waste' means dividing the waste into different categories like dry and wet or biodegradable and non- biodegradable. Dry waste consists of waste that does not decay and is non- biodegradable. Ex aluminium foils, tetra packs, plastic products, broken crockery, steel utensils and glass. Wet waste comprises waste that is organic in nature and is biodegradable, i.e., it can be decomposed or broken down by living organisms. Ex- vegetables and fruit peels, stale food, rotten fruits and vegetables, etc. When waste is segregated, there occurs a reduction in the volume of waste that reaches landfills. Air and water pollution is considerably reduced and it becomes easier to apply different processes of waste disposal like composting, recycling and incineration. In fact, segregation of waste is the key to effective waste management. Urban residential colonies should undertake collective efforts for safe disposal of domestic as well as sweepings from the gardens and public parks. These sweepings can be converted into compost and used for the maintenance of these gardens and parks. Sorting out of the reusable material from heaps of waste may often involve much manual labour. In a country like India, the poor rag pickers make a living by sorting out reusable and recyclable items from discarded solids. Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu SEGREGATION OF WASTE Waste can be segregated as: 1. Biodegradable; and 2. Non-biodegradable. Biodegradable waste includes 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.; and b) Toxic waste old medicines, paints, chemicals, bulbs, spray cans, fertilizers and pesticide containers, batteries, shoe polish. c) Soiled hospital waste such as cloth soiled with blood and other body fluids. Toxic and soiled waste must be disposed of with utmost care. DUMPING Open Dumping: In this method, waste materials are dumped in open low lands far away from the city. This method is not environment friendly. This is the cheapest method and does not need much planning. The open pits spoil the sight of the area and become a breeding ground for mosquitoes, flies, insects, etc., that are the carriers of harmful diseases. They give out foul odour. The burning of waste material in the open dumps pollutes the air. Another danger of open dumping is that rainwater could carry the harmful substances to the nearby streams, ponds or lakes and if the water seeps down it could pollute the groundwater. Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu Sanitary Landfill: In this method, the waste is packed and dumped daily at the site and is covered with earth to prevent insects or rodents from entering into the landfill. The waste then is subjected to bacterial decomposition. Physical, chemical and biological reactions take place generating different gases which is used to generate power. Sanitary landfill is a way of disposing refuse on land without creating nuisances or hazards to public health or safety. In a sanitary landfill biological method of disposing of waste is used. The waste undergoes the following five phases: (i) In the first phase of operation, aerobic bacteria depletes the available oxygen and causes the temperature to increase. (ii) In the second phase, anaerobic conditions get established and lead to the evolution of hydrogen and carbon dioxide. (iii) Phase three establishes population of bacteria and the beginning of methanogenic activity, i.e., production of methane from the decomposition of organic matter. (iv) In the fourth phase the methanogenic activity becomes stabilised. (v) The fifth phase depletes the organic matter, and the system returns to aerobic state. ADVANTAGES: The advantages of sanitary landfill as opposed to open dumping are: It is free from air pollution from burning. Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu  The health problems are minimised since flies, rats and other pests cannot breed in the landfill because of the covered wastes. It is mostly free from fire hazards. PLANTATION AT LANDFILL SITE A vegetative cover should be provided over the landfill site in accordance with the following specifications: (i) Locally adopted non-edible perennial plants that are resistant to drought and extreme temperatures should be planted. (ii) The plants grown should be such that their roots do not penetrate more than 30 cms. This condition should apply till the landfill is stabilised. (iii) Selected plants should have the ability to thrive on low-nutrient soil with minimum nutrient addition. (iv) Plantation should be made in sufficient density to minimise soil erosion. MUNICIPAL WASTE MANAGEMENT 1. Collection of Municipal Solid Wastes The following steps should be taken by the municipal authorities: (i) Organising house-to- house collection of municipal solid wastes. Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu (ii) Devising collection of waste from slums and squatter areas or localities. (iii) Bio-medical wastes and industrial wastes should not be mixed with municipal solid wastes. (iv) Horticultural and construction wastes should be separately collected and disposed of. (v) The waste should be segregated into biodegradable and non- biodegradable. (vi) Waste (garbage, dry leaves) should not be burnt. (vii) Stray animals should not be allowed to move around waste storage facilities. 2. Storage of Municipal Solid Wastes The following criteria should be taken into account while establishing and maintaining storage facilities: (i) Storage facilities should be set up and established by taking into account quantities of waste generation in an area and its population density. (ii) These facilities are to be so designed that wastes stored are not exposed to open atmosphere and are aesthetically acceptable and user-friendly; (iii) Storage facilities or 'bins' should have 'easy to operate' design for handling, transfer and transportation of waste. (iv) Manual handling of waste should be avoided. Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu 3. Transportation of Municipal Solid Wastes Vehicles used for transportation of wastes should be covered. This prevents the wastes from being scattered. Waste should not be visible to public, nor exposed to open environment. 4. Community Participation in Segregation of Municipal Solid Wastes The municipal authorities should undertake phased programme to ensure community participation in waste segregation. COMPOSTING Composting of waste is an aerobic (in the presence of air) method of decomposing solid wastes. The organic wastes from households are made to undergo decomposition in such a way that bacteria and other micro-organisms break them down and produce a safe, clean and soil-like material called compost. In India, both the manual as well as mechanical methods of composting are used. In the rural areas, layers of vegetable waste and night soils are alternated in a shallow hole dug in the ground. The mixture is turned regularly for about three months to provide air to the mixture. Then the compost is left for another month without turning for the process to take effect. This method of composting is known as the Indore Method. Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu In the mechanical process, used in Bengaluru and adopted by other cities in the country, the waste material is placed in layers about one metre deep. The material is not turned at all but it decomposes completely in about five months. This method of composting is known as the Bengaluru Method. ADVANTAGES OF COMPOSTING The major benefits of composting are: (i) It enhances soil nutrients and water retention capacity of soils. (ii) It suppresses plant diseases. (iii) If rejuvenates poor soils by adding humus. (iv) It absorbs odours and degrades volatile organic compounds. (v) It prevents pollution by preventing pollutants in storm water run- off from draining into water resources. (vi) It checks soil erosion and silting on embankments. (vii) It reduces cost as there is no need for excess water, fertilizers and pesticides. INCINERATION In cities, vacant areas for disposal sites are not very many; so incineration process is used for waste disposal Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu by industries and municipalities. Incineration is the process of controlled high temperature oxidation of primarily organic compounds that release thermal energy and produce carbon dioxide and water. In short, incineration involves burning of wastes at a very high temperature. Incineration is a useful technology to deal with large quantities of organic hazardous wastes that have high calorific value and cannot be dealt with by other methods. By this method pathogenic organisms are killed and the volume of the waste is reduced upto 50 per cent. However, incineration process has its limitations - (i) it is quite expensive; (ii) it generates ash and combustion gases which have an adverse impact on human health and environment; (iii) incineration consumes significant amount of energy to achieve high temperature. REDUCE-REUSE-RECYCLE WASTE Waste can be effectively managed by using the following three R's of waste management: (i) Reducing the Waste; (ii) Reusing the Waste; and (iii) Recycling the Waste. REDUCING THE WASTE The waste can be reduced by making use of the following methods: (a) Change of Process: In industries, changes can be made in the production process to reduce waste generation. This reduction can be Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu achieved by either changing the material used to finish the product or by using more efficiently the input materials in the production process or both. (b) Waste Concentration: By using scientific techniques such as precipitation and evaporation the amount of liquid waste can be reduced. Incineration can be used to get rid of inflammable wastes. (c) Segregation of Waste: First of all, non-hazardous waste are separated from hazardous waste rather than dumping them together. Then the small amount of hazardous waste can be treated. We can dispose of a large amount of non-hazardous waste in the traditional ways. REUSING THE WASTE In our houses and in industries many materials are discarded as wastes. These materials have some value, for instance glass, metal pieces, rubber, wood fibres and paper products. In developing countries like India, some of the waste materials like old glass bottles, steel tyres, tin cans are reused. For example, shoes or chappals are made from old tyres, water bags are made from leather, lamps are made from tin cans, etc. For example, a beautiful garden (Rock Garden) has been created by Nek Chand in Chandigarh using waste products like tin cans, bottles, broken pieces of crockery, etc. Some solid wastes from the industry can be utilised directly. Flyash from power plants is used as a substitute for cement. Bricks are made from flyash. Flyash is also used in making roads and filling up low-lying areas. Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu RECYCLING OF WASTE Recycling means treating the waste before it is used in a manufacturing process. Bagasse is used in the manufacture of paper pulp. This helps to save trees which are normally used for making paper pulp. Bagasse is also used for making packaging material for dairy products. Paper industry recycles pieces of wood from furniture industry, used and discarded cloth and used paper. Plastics are recycled by plastic manufacturers. About 80 per cent of the plastic waste is recycled in India. ROADS FROM PLASTIC WASTE A Government of India Order in November 2015 made it mandatory for all road developers in the country to use waste plastic, along with bituminous mixes, for constructing the roads. This was done to overcome the growing problem of plastic waste disposal in the country. The technology for this was developed by the 'Plastic Man' of India, Prof. Rajagopalan Vasudevan, Professor of Chemistry at Thiagarajar College of Engineering, Madurai. Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu The plastic waste items that can be used for road construction include plastic carry bags, plastic cups, plastic packaging for potato chips, biscuits, chocolates, etc. For making roads, the plastic waste material is first shredded to a particular size using a shredding machine. The aggregate mix is heated at 165°C and transferred to the mixing chamber, and the bitumen is heated to 160°C to result in good binding. The shredded plastic waste is then added to the aggregate. It gets coated uniformly over the aggregate within 30 to 60 seconds, giving an oily look. The plastic waste coated aggregate is mixed with hot bitumen and the resulting mix is used for road construction. ADVANTAGES: The advantages of using waste plastics for road construction are the following: The process is easy and does not need any new machinery. For every kilo of stone, 50 gms of bitumen is used and 1/10th of this is plastic waste; this reduces the amount of bitumen being used. Plastic increases the aggregate impact value and improves the quality of flexible pavements. Wear and tear of the roads is also quite low. This road construction process is eco-friendly, with no toxic gases being released. Plastic waste helps increase the strength of the road, reducing road fatigue. These roads have better resistance towards rain water and cold weather. Since a large amount of plastic waste is required for a small stretch of road, the amount of waste plastic strewn around gets tremendously reduced. Click here to buy Latest ICSE Class 10 Books-https://amzn.to/3xib8Bu