Environmental polluttion


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Environmental polluttion

  1. 1. Cross Curricular project Topic: Environmental Pollution Submitted by:-Group 3 Jawahar Class;-10th Navodaya Vidyalaya Session:-2013-14 B. Cuttack, Rayagada Guided by:-Mr. J.Sahoo (PGT Math) Mr. P.R.Pilli (TGT English) Mr. J.verma (TGT S.Sc) Mr. K. Sahoo (PGT Chemistry) Mr. D. Mohanty (PGT Physics) Mr. J. Racheta(PGT Biology) Name of the group member Saroj Kumar Padhy
  2. 2. Siba Sankar Sahu Manoj Naik Santosh Sabar D.Sai Kumar N. Tanmay Prasanta Garadia Tapan Hikaka ACKNOWLEDGEMENT
  3. 3. This work was initiated by our all teacher for whom we have had great regard. It has been our privileged to continue the project and see it successfully through to completion. This would not have been possible but for the support and cooperation we received from various individual .At last we want to acknowledge to our computer teacher and other teachers and them who raised their helping hand towards this project. Certificate This is to certify that a project entitled ‘Environmental Pollution’ was made for the cross curricular project to be submitted for the FA-3 for the academic session 2013-14. SIGN OF THE PRINCIPAL Content 1. Introduction
  4. 4. 2. What is pollution 3. Types of pollution 4. Air pollution 5. Light pollution 6. Littering 7. Noise pollution 8. Water pollution 9. Soil pollution 10. Thermal pollution 11. Conclusion 12. Bibliography Introduction Environmental pollution is any discharge of material or energy into water, land, or air that causes or may cause acute or chronic detriment to the Earth's ecological balance or that lowers the quality of life. Pollutants may cause primary damage, with direct identifiable
  5. 5. impact on the environment, or secondary damage in the form of minor perturbations in the delicate balance of the biological food web that are detectable only over long time periods. The industrialization of society, the introduction of motorized vehicles, and the explosion of the human population, however, have caused an exponential growth in the production of goods and services. Coupled with this growth has been a tremendous increase in waste byproducts. The indiscriminate discharge of untreated industrial and domestic wastes into waterways. the spewing of thousands of tons of particulates and airborne gases into the atmosphere, the "throwaway" attitude toward solid wastes, and the use of newly developed chemicals without considering potential consequences have resulted in major environmental disasters, including the formation of smog in the Los Angeles area since the late 1940s and the pollution of large areas of the Mediterranean Sea. Technology has begun to solve some pollution problems and public awareness of the extent of pollution will eventually force governments to undertake more effective environmental planning and adopt more effective antipollution measures. WHAT IS POLLUTION? Pollution is any discharge of material or energy into water, land, or air that causes or may cause acute or chronic detriment to the Earth's ecological balance or that lowers the quality of life or in simple terms we can say that pollution is the contamination of the waste materials into the earth’s ecology. Pollutants may cause primary damage, with direct identifiable impact on the
  6. 6. environment, or secondary damage in the form of minor perturbations in the delicate balance of the biological food web that are detectable only over long time periods. TYPES OF POLLUTION Pollution is of following types:1. 2. 3. 4. 5. 6. 7. Air pollution Light pollution Littering Noise pollution Water pollution Soil contamination Thermal pollution Air pollution Air pollution is the introduction of chemicals, particulates, or biological materials into the atmosphere that cause discomfort, disease, or death to humans, damage other living organisms such as food crops, or damage the natural environment or environment. The atmosphere is a complex dynamic natural gaseous system that is essential to support life on planet Earth. Stratospheric ozone depletion due to air pollution has long been recognized as a threat to human health as well as to the Earth's ecosystems. Indoor air pollution (see Air log) and urban air quality are listed as two of the World’s Worst Toxic Pollution Problems in the 2008 Blacksmith Institute World's Worst Polluted Places report.
  7. 7. Sources of air pollution The sources of air pollution are classified into two groups: 1. Natural Sources 2. Man made sources Natural Sources of Air Pollution:-They are dust storms, forest fires, ash from smoking volcanoes, decay of organic matters and pollen grains floating in air. Manmade Sources of Air Pollution:- They are population explosion, deforestation, urbanization and industrialization, whose effects can be explained as follows: 1. Burning of fuels like wood, cow dung cakes, coal and kerosene in homes pollute the air. 2. Exhaust gases emitted by motor vehicles which pollute the air are the major source of air pollution in big cities. 3. Industries pollute air by releasing various types of pollutants such as sulphur dioxide, oxides of carbon, nitrogen oxide, chlorine, asbestos dust and cement dust. 4. Thermal power plants pollute air by emitting sulphur dioxide and fly-ash. 5. Nuclear power plants pollute air by releasing radioactive rays. 6. Use of fertilisers and pesticides in agriculture pollute the air. 7. Mining activities releases particulate matter into the air and pollutes it. 8. Indiscriminate cutting of trees and clearing of forests increases the amount of carbon dioxide in the atmosphere and thereby pollutes it. 9. Use of chlorofluorocarbons in refrigerators, fire extinguishers and aerosol sprayers pollutes air by depleting the ozone layer. Schematic drawing, causes and effects of air pollution:(1) greenhouse effect, (2) particulate contamination, (3) increased UV radiation, (4) acid rain,
  8. 8. (5) increased ground level ozone concentration, (6) increased levels of nitrogen oxides. Major primary pollutants produced by human activity include: Sulphur oxides (SO2) - especially sulphur dioxide, a chemical compound with the formula SO2. SO2 is produced by volcanoes and in various industrial processes. Since coal and petroleum often contain sulphur compounds, their combustion generates sulfur dioxide. Further oxidation of SO2, usually in the presence of a catalyst such as NO2, forms H2SO4, and thus acid rain.[2] This is one of the causes for concern over the environmental impact of the use of these fuels as power sources. Nitrogen oxides (NO2) - especially nitrogen dioxide are expelled from high temperature combustion, and are also produced naturally during thunderstorms by electric discharge. Can be seen as the brown haze dome above or plume downwind of cities. Nitrogen dioxide is the chemical compound with the formula NO2. It is one of the several nitrogen oxides. This reddish-brown toxic gas has a characteristic sharp, biting odor. NO2 is one of the most prominent air pollutants. Carbon monoxide (CO) :- is a colourless, odourless, non-irritating but very poisonous gas. It is a product by incomplete combustion of fuel such as natural gas, coal or wood. Vehicular exhaust is a major source of carbon monoxide. Volatile organic compounds - VOCs are an important outdoor air pollutant. In this field they are often divided into the separate categories of methane (CH4) and non-methane (NMVOCs). Methane is an extremely efficient greenhouse gas which contributes to enhance global warming. Other hydrocarbon VOCs are also significant greenhouse gases via their role in creating ozone and in prolonging the life of methane in the atmosphere, although the effect varies depending on local Air quality. Chlorofluorocarbons (CFCs) – They are harmful to the ozone layer emitted from products currently banned from use. Ammonia (NH3) - emitted from agricultural processes. Ammonia is a compound with the formula NH3. It is normally encountered as a gas with a characteristic pungent odor. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to foodstuffs and fertilizers. Ammonia, either directly or indirectly, is also a building block for the synthesis of many pharmaceuticals. Although in wide use, ammonia is both caustic and hazardous.
  9. 9. Harmful Effects of Air Pollution: 1. Air pollution affects respiratory system causing breathing difficulties and diseases such as bronchitis, asthma, lung cancer, tuberculosis and pneumonia. 2. Air Pollution affects the central nervous system causing carbon monoxide poisoning.CO has more affinity for hemoglobin than oxygen and thus forms a stable compound carboxyl hemoglobin(COHb),which is poisonous and causes suffocation and death. 3. Air pollution causes depletion of ozone layer due to which ultraviolet radiations can reach the earth and cause skin cancer, damage to eyes and immune system. 4. It causes acid rain which damages crop plants, trees, buildings, monuments, statues and metal structures and also makes the soil acidic. 5. It causes greenhouse effect or global warming which leads to excessive heating of earth's atmosphere, further leading to weather variability and rise in sea level. The increased temperature may cause melting of ice caps and glaciers, resulting in floods. 6. Air pollution from certain metals, pesticides and fungicides causes serious ailments. Lead pollution causes anaemia, brain damage, convulsions and death. Certain metals cause problem in kidney, liver, circulatory system and nervous system. Fungicides cause nerve damage and death. Pesticides like DDT(Dichloro diphenyl trichloroethane) which are toxic enter into our food chain and gets accumulated in the body causing kidney disorders and problems of brain and circulatory system. Prevention And Control of Air Pollution:Different techniques are used for controlling air pollution caused by 'gaseous pollutants' and that caused by 'particulate pollutants'. Methods of controlling gaseous pollutants:The air pollution caused by gaseous pollutants like hydrocarbons,sulphur dioxide,ammonia,carbon monoxide,etc can be controlled by using three different methodsCombustion,Absorption and Adsorption. 1. Combustion:- This technique is applied when the pollutants are organic gases or vapours. The organic air pollutants are subjected to 'flame
  10. 10. 2. 3. 1. 2. 3. combustion or catalytic combustion' when they are converted to less harmful product carbon dioxide and a harmless product water. Absorption:- In this method,the polluted air containing gaseous pollutants is passed through a scrubber containing a suitable liquid absorbent.The liquid absorbs the harmful gaseous pollutants present in air. Adsorption:In this method,the polluted air is passed through porous solid adsorbents kept in suitable containers.The gaseous pollutants are adsorbed at the surface of the porous solid and clean air passes through. Methods of controlling particulate emissions:- The air pollution caused by particulate matter like dust,soot,ash,etc, can be controlled by using fabric filters,wet scrubbers,electrostatic precipitators and certain mechanical devices. Mechanical Devices:- It works on the basis of following:Gravity:- In this process,the particulate settle down by the action of gravitational force and get removed. Sudden change in the direction of air flow:- It brings about separation of particles due to greater momentum. Fabric Filters:- The particulate matter is passed through a porous medium made of woven or filled fabrics. The particulate present in the polluted air are filtered and gets collected in the fabric filters, while the gases are discharged. Wet Scrubbers:- They are used to trap SO2,NH3 and metal fumes by passing the fumes through water. Light Pollution Light pollution is the pollution caused by misplaced artificial light. It is a growing problem that threatens wildlife, humans, natural habitats, our energy use and the heritage of appreciation for our night sky. Leaving lights on in vacant buildings, outdoor lights pointing up to the sky and unshielded outdoor lights all contribute to light pollution or sky glow. There are 4 different components of light pollution: Urban sky-glow: Artificial lights that are pointed upwards or misplaced cause the sky to unnaturally “glow” blocking the view of stars. Light trespass: Light that lands in areas where it is not wanted or needed. Example: light from a neighbor’s house is also lighting up your back yard.
  11. 11. Glare: The bright uncomfortable light that comes off of poorly built lamps. This causes a decrease in visibility. Clutter: A grouping of bright light (Example: New York City) contributing to skyglow, trespass, and glare. Light Pollution and Humans Light pollution has consequences for human health. Night vision can be severely impacted. Glare on the eyes from excessive night lighting can cause disability glare. Disability glare is glare from roadway lighting that is so bright it causes us to avert our eyes. Older drivers are particularly vulnerable to disability glare. Disability glare reduces: · Ability to distinguish contrast · Color perception The aging eye is also susceptible to eyestrain and loss of night vision. Light Pollution and Wildlife Light pollution also negatively affects animals in a bigger way than most would think. The sky glow from towns and cities cause nocturnal wildlife around the world to experience a loss of their night ecosystem. Mammals: Mammals lose a lot of their internal night systems due to over lit areas. Nocturnal animals such as raccoons, bats, and deer suffer greatly, causing a decrease in population, difficulties with finding food, exposure to predators, and an increase in mortality. Amphibians: Light pollution causes amphibians to suffer by lowering population, decrease in body weight, and confusion between insects that protect nature rather than harming it. If an ecosystem is anywhere near an urban area with high amounts of light pollution, amphibians will suffer.
  12. 12. Insects: You have probably seen insects fly around your porch light. This is a striking example of how artificial light affects wildlife. Insects such as moths and flies suffer a decrease in population due to light pollution because it is easier for predators to hunt the insects. The decreased insect population impacts all the animals that feed on insects as their main food source. Birds: If any animal species suffer from light pollution, birds definitely suffer the most. Over 100 million birds in the United States die from collisions with lighted buildings alone. The lighted buildings attract them. That’s not all; some migrating birds don’t reach their destination because the artificial lights interfere with their navigation and can throw them off course. Reptiles: As you may know, sea turtles travel up on beach shores to bury their eggs in the sand. But what if the beach is near a bright urban area? Baby sea turtles rely on the moon to lead them to the sea. Artificial light can lead them to roads where cars can run them over or to someplace far off until they die from exhaustion. This explains one reason why sea turtles are decreasing in population. Causes of light pollution Light pollution is caused by uncontrolled emissions and reflections. The design of most of the light emitting sources allows a significant fraction of light to go up in the sky. Excessive use of light emitting sources also causes significant loss of light energy and increases the production of greenhouse gases. Careless outdoor lighting is also responsible for light pollution. Estimates point out that about one-third of the energy used for outdoor lighting is sent to outer space where it doesn't serve any useful purpose and causes light pollution. The rate at which the urban areas are expanding is contributing to the increase in the levels of light pollution. The range of new outdoor lighting products has also led to an increase in the light pollution levels. Three decades ago, the outdoor lighting products that were available to the public were limited to incandescent lights, mercury vapor lamps, etc. but today more powerful fixtures are available. These products are more powerful than needed and are poorly shielded causing light to spill in areas where it
  13. 13. is not needed. Control of light pollution The following steps can be taken to reduce the light pollution:1. Avoid causing light pollution do not fit unnecessary lights do not use excessively bright lights, a 150 watt tungsten halogen lamp is quite adequate, 300 or 500 watt bulbs are too powerful for domestic security lighting 2. Action against light pollution If you are experiencing light pollution from your neighbours try approaching the owner of the offending light, politely requesting: re-angling or partial shading of the light fitting of a passive infra red sensor using a lower power bulb Littering Litter is the biggest cause of visual pollution and impacts on our environment causing damage to waterways and harm to animal and marine life. It is expensive to clean up and a difficult issue to police. The presence of litter increases the likelihood of socially unacceptable behaviour as it sends the message that the area is uncared for. People are more likely to report feeling unsafe in a littered area and have a lower level of satisfaction with a littered community. Litter includes a broad range of items and can occur almost anywhere, from places where people frequent, to places people seek out to dump their material. Littering behaviour is fascinatingly complex and research shows that there is no typical 'litterer.
  14. 14. There are many different ways people litter from leaving things behind to stuffing their litter in nooks and crannies to flinging items out of cars. People’s reasons for littering vary widely and what people report that they do, upon closer observation, is not necessarily how they behave. Effects of litter Effect on humans:Litter can harm humans and the environment in different ways. Hazardous materials contained within litter and illegally dumped rubbish can leach into water sources, contaminate soil and pollute the air. When tires are burned they can smoulder for long periods of time emitting hundreds of chemical and compounds that pollute the air causing respiratory illnesses. Additionally the residue left behind can harm the soil and leach into groundwater. Visual pollution is a major effect of litter. Effect on wildlife:Animals may get trapped or poisoned with litter in their habitats. Cigarette butts and filters are a threat to wildlife and have been found in the stomachs of fish, birds and whales, who have mistaken them for food. Also animals can get trapped in the rubbish and be in serious discomfort. For example, the plastic used to hold beverage cans together can get wrapped around animals' necks and cause them to suffocate as they grow. Other instances where animals could be harmed by litter include broken glass lacerating the paws of dogs, cats, and other small mammals, fishing net being caught around the neck of a seal, etc. Why do people litter? The reasons people might litter include: Laziness. More than half of all littering occurs within five metres of a garbage can or bin
  15. 15. Deliberate action. Often litter is not simply left behind, but placed carefully in chosen locations Poor design and location of garbage cans Not enough garbage cans Habit and forgetfulness Unavailability of ashtrays What are some possible solutions? Make sure you waste goes in a garbage bin – beside it is not enough! Take your garbage home with you when visiting a local park or beach Pack a litter less lunch by using reusable containers Use reusable bags, instead of plastic bags, when shopping Noise pollution Noise pollution is the disturbing or excessive noise that may harm the activity or balance of human or animal life. The source of most outdoor noise worldwide is mainly caused by machines and transportation systems, motor vehicles, aircraft, and trains. Outdoor noise is summarized by the word environmental noise. Poor urban planning may give rise to noise pollution, since side-by-side industrial and residential buildings can result in noise pollution in the residential areas. Indoor noise is caused by machines, building activities, music performances, and especially in some workplaces. There is no great difference whether noise-induced hearing loss is brought about by outside (e.g. trains) or inside (e.g. music) noise. High noise levels can contribute to cardiovascular effects in humans, a rise in blood pressure, and an increase in stress and vasoconstriction, and an increased
  16. 16. incidence of coronary artery disease. In animals, noise can increase the risk of death by altering predator or prey detection and avoidance, interfere with reproduction and navigation, and contribute to permanent hearing loss. Effects of noise pollution Effect to humans:- Noise pollution affects both health and behaviour. Unwanted sound (noise) can damage psychological health. Noise pollution can cause annoyance and aggression, hypertension, high stress levels, tinnitus, hearing loss, sleep disturbances, and other harmful effects. Furthermore, stress and hypertension are the leading causes to health problems. Sound becomes unwanted when it either interferes with normal activities such as sleeping, conversation, or disrupts or diminishes one’s quality of life. High noise levels can contribute to cardiovascular effects and exposure to moderately high levels during a single eight-hour period causes a statistical rise in blood pressure of five to ten points and an increase in stress, and vasoconstriction leading to the increased blood pressure noted above, as well as to increased incidence of coronary artery disease. Noise pollution also is a cause of annoyance. A 2005 study by Spanish researchers found that in urban areas households are willing to pay approximately four Euros per decibel per year for noise reduction. Effects on wildlife:- Wildlife faces far more problems than humans because noise pollution since they are more dependent on sound. Animals develop a better sense of hearing than us since their survival depends on it. The ill effects of excessive noise begin at home. Pets react more aggressively in households where there is constant noise. They become disoriented more easily and face many behavioural problems. In nature, animals may suffer from hearing loss, which makes them easy prey and leads to dwindling populations. Others become inefficient at hunting, disturbing the balance of the eco-system. Species that depend on mating calls to reproduce are often unable to hear these calls due to excessive man made noise. As a result, they are unable to reproduce and cause declining populations. Others require sound waves to echo-locate and find their way when migrating. Disturbing their sound signals means they get lost
  17. 17. easily and do not migrate when they should. To cope up with the increasing sound around them, animals are becoming louder, which may further add to the pollution levels. Causes of noise pollution 1. Industrialization: Most of the industries use big machines which are capable of producing large amount of noise. Apart from that, various equipments like compressors, generators, exhaust fans, grinding mills also participate in producing big noise. 2.Poor Urban Planning: In most of the developing countries, poor urban planning also play a vital role. Congested houses, large families sharing small space, fight over parking, frequent fights over basic amenities leads to noise pollution which may disrupt the environment of society. 3. Social Events: Noise is at its peak in most of the social events. Whether it is marriage, parties, pub, disc or place of worship, people normally flout rules set by the local administration and create nuisance in the area. People play songs on full volume and dance till midnight which makes the condition of people living nearby pretty worse. In markets people selling clothes via making loud noise to attract the attention of people. 4. Transportation: Large number of vehicles on roads, aeroplanes flying over houses, underground trains produce heavy noise and people get it difficult to get accustomed to that. The high noise leads to a situation wherein a normal person lose the ability to hear properly. 5. Construction Activities: Under construction activities like mining, construction of bridges, dams, buildings, stations, roads, flyovers take place in almost every part of the world. These construction activities take place everyday as we need more buildings, bridges to accommodate more people and to reduce traffic congestion. The down point is that these construction equipments are too noisy. Control of noise pollution There are many methods which help to control the noise pollution. The source of noise must be reduced. The path of transmission of sound must be stopped and the receiver of noise must be safe guarded.
  18. 18. The amount of traffic must be reduced near the residential homes, educational institutes and hospitals. The machinery must be redesigned and the vehicles must be properly maintained. The acoustical furnishing must be done so that the sound can be absorbed. The industries must be built away from the residential areas and the legal laws must be established and observed to protect the humans from noise pollution. A general awareness programme to educate the people must be done. Water pollution Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans, aquifers and groundwater). Water pollution occurs when pollutants are directly or indirectly discharged into water bodies without adequate treatment to remove harmful compounds. Water pollution affects plants and organisms living in these bodies of water. In almost all cases the effect is damaging not only to individual species and populations, but also to the natural biological communities. Types of water pollution There are many types of water pollution because water comes from many sources. Here are a few types of water pollution: 1. Nutrients Pollution Some wastewater, fertilizers and sewage contain high levels of nutrients. If
  19. 19. they end up in water bodies, they encourage algae and weed growth in the water. This will make the water undrinkable, and even clog filters. Too much algae will also use up all the oxygen in the water and other water organisms in the water will die out of oxygen from starvation. 2. Surface water pollution Surface water includes natural water found on the earth's surface, like rivers, lakes, lagoons and oceans. Hazardous substances coming into contact with this surface water, dissolving or mixing physically with the water can be called surface water pollution. 3. Oxygen Depleting Water bodies have micro-organisms. These include aerobic and anaerobic organisms. When to much biodegradable matter (things that easily decay) end up in water, it encourages more microorganism growth, and they use up more oxygen in the water. If oxygen is depleted, aerobic organisms die, and anaerobic organism grow more to produce harmful toxins such as ammonia and sulfides. 4. Ground water pollution when humans apply pesticides and chemicals to soils, they are washed deep into the ground by rain water. This gets to underground water, causing pollution underground. This means when we dig wells and bore holes to get water from underground, it needs to be checked for ground water pollution. 5. Microbiological In many communities in the world, people drink untreated water (straight from a river or stream). Sometimes there is natural pollution caused by microorganisms like viruses, bacteria and protozoa. This natural pollution can cause fishes and other water life to die. They can also cause serious illness to humans who drink from such waters. 6. Suspended Matter Some pollutants (substances, particles and chemicals) do not easily dissolve in water. This kind of material is called particulate matter. Some suspended pollutants later settle under the water body. This can harm and even kill aquatic life that live at the floor of water bodies. 7. Chemical Water Pollution Many industries and farmers work with chemicals that end up in water.
  20. 20. These include chemicals that are used to control weeds, insects and pests. Metals and solvents from industries can pollute water bodies. These are poisonous to many forms of aquatic life and may slow their development, make them infertile and kill them. 8. Oil Spillage Oil spills usually have only a localized affect on wildlife but can spread for miles. The oil can cause the death of many fish and stick to the feathers of seabirds causing them to lose the ability to fly. Effects of water pollution The effects of water pollution are varied and depend on what chemicals are dumped and in which locations. Many water bodies near urban areas (cities and towns) are highly polluted. This is the result of both garbage dumped by individuals and dangerous chemicals legally or illegally dumped by manufacturing industries, health centers, schools and market places. 1.Death of aquatic (water) animals The main problem caused by water pollution is that it kills life that depends on these water bodies. Dead fish, crabs, birds and sea gulls, dolphins, and many other animals often wind up on beaches, killed by pollutants in their habitat (living environment).
  21. 21. 2.Disruption of food-chains Pollution disrupts the natural food chain as well. Pollutants such as lead and cadmium are eaten by tiny animals. Later, these animals are consumed by fish and shellfish, and the food chain continues to be disrupted at all higher levels. 3.Diseases Eventually, humans are affected by this process as well. People can get diseases such as hepatitis by eating seafood that has been poisoned. In many poor nations, there is always outbreak of cholera and diseases as a result of poor drinking water treatment from contaminated waters. 4. Destruction of ecosystems Ecosystems (the interaction of living things in a place, depending on each other for life) can be severely changed or destroyed by water pollution. Many areas are now being affected by careless human pollution, and this pollution is coming back to hurt humans in many ways. Control of water pollution Water pollution is a major environmental concern today that adversely affects the surroundings, causing serious injury to the environment as well as human health. At JSPL, water pollution is controlled by adopting a range of stringent regulatory measures and monitoring processes. The company has attained ‘Zero Discharge’ status by adopting state-of-the-art technology for water treatment. As per the guidelines of CREP, a 4.3 – 4.9 m3 per T of long product is currently being used by JSPL. Through effective water conservation and reuse methods specific water consumption for long product and flat product is maintained within range of 4.2 – 5.3 which is much below the CREP guideline of MoEF. Some of the measures, which have been implemented for effective control of water pollution, are as follows: Coke Oven Quenching: The waste water generated during quenching is taken to settling tanks. After settling, the water is reused for quenching the hot coke. Sinter plant: Blow-down water is used in sinter nodulizing.
  22. 22. Blast furnace: Dust laden waste water is treated in effluent treatment plants and the treated water is recycled back to the process to scrub blast furnace gas. SMS: The waste water is taken to a settling tank and the outlet water of the tank is reused. The blow-down water is used in slag granulation. Rolling mill: Process waste water is skimmed for oil and scale and then recycled back to the plant. No wastewater is discharged. DRI: Cooling close-circuit effluent-recycling system has been installed. Waste water from the cooling section is taken to a hot water well and then to the cooling tower and the cold water well, from where it is recycled back into the process. Power Plant: DM plant wastewater is treated in the neutralization pit. After treatment, the water is reused for wet ash handling system. Submerged Arc Furnace: Waste water is reused for slag cooling and dust suppression. Sewage Treatment Plants (STP): Three sewage treatment plants (combined capacity 3050 KL/ day) have been installed. The treated water is 100% reused for horticulture and green cover. Garage, DG Set & Compressor Houses: Oil separators have been provided. Clean water is further treated in the STP. Soil pollution Soil contamination or soil pollution is caused by the presence of xenobiotic (human-made) chemicals or other alteration in the natural soil environment. It is typically caused by industrial activity, agricultural chemicals, or improper disposal of waste. The most common chemicals involved are petroleum hydrocarbons, polynuclear aromatic hydrocarbons (such as naphthalene and benzo (a) pyrene), solvents, pesticides, lead, and other heavy metals. Contamination is correlated with the degree of industrialization and intensity of chemical usage Types of soil pollution Soil pollution is of following types:1. Agricultural Soil Pollution
  23. 23. I. pollution of surface soil II. pollution of underground soil 2. Soil pollution by industrial effluents and solid wastes I. pollution of surface soil II. disturbances in soil profile 3. Pollution due to urban activities I. II. pollution of surface soil pollution of underground soil Causes of soil pollution Soil pollution is a result of many activities and experiments done by mankind which end up contaminating the soil. Here are some of the leading soil pollution causes: 1. Industrial wastes such as harmful gases and chemicals, agricultural pesticides, fertilizers and insecticides are the most common causes of soil pollution. 2. Ignorance towards soil management and related systems. 3. Unfavorable and harmful irrigation practices. 4. Improper septic system and management and maintenance of the same. 5. Leakages from sanitary sewage. 6. Acid rains, when fumes released from industries get mixed with rains. 7. Fuel leakages from automobiles, that get washed away due to rain and seep into the nearby soil. 8. Unhealthy waste management techniques, which are characterized by release of sewage into the large dumping grounds and nearby streams or rivers. The intensity of all these causes on a local or regional level might appear very small and you may argue that soil is not harmed by above activities if done on a small scale! However, thinking globally, it is not your region or my place that will be the only sufferer of soil pollution. In fact, it is the entire planet and mankind that will encounter serious problems, as these practices are evident almost everywhere in the world.
  24. 24. Effects of soil pollution The effects of pollution on soil are quite alarming and can cause huge disturbances in the ecological balance and health of living creatures on earth. Some of the most serious soil pollution effects are: 1. Decrease in soil fertility and therefore decrease in the soil yield. How can one expect contaminated soil to produce healthy crops? 2. Loss of soil and natural nutrients present in it. Plants also would not thrive in such soil, which would further result in soil erosion. 3. Disturbance in the balance of flora and fauna residing in the soil. 4. Increase in salinity of the soil, which therefore makes it unfit for vegetation, thus making it useless and barren. 5. Generally crops cannot grow and flourish in polluted soil. Yet, if some crops manage to grow, they would be poisonous enough to cause serious health problems in people consuming them. 6. Creation of toxic dust is another potential effect of soil pollution. 7. Foul smell due to industrial chemicals and gases might result in headaches, fatigue, nausea, etc., in many people. 8. Soil pollutants would bring in alteration in the soil structure, which would lead to death of many essential organisms in it. This would also affect the larger predators and compel them to move to other places, once they lose their food supply. Soil pollution can be cured by transporting the contaminated soil layer to some remote place, thus making it once again fit for use. Harmful chemicals from the soil can also be removed by aerating it. These are just 'tentative solutions'. However, let us remember the proverb, 'prevention is better than cure', and follow proper a soil management system, maintain sewage systems, and avoid the overuse of fertilizers and pesticides in the soil. So let us begin the movement of soil pollution prevention from our own lands itself!!! Prevention of soil pollution The following steps can be taken to control the soil pollution:-
  25. 25. 1. 2. 3. 4. 5. 6. Use of pesticides should be minimized. Use of fertilisers should be judicious Cropping techniques should be improved to prevent growth of weeds. Special pits should be selected for dumping wastes. Controlled grazing and forest management. Wind breaks and wind shield should be built in the areas exposed to wind erosion 7. Planning of soil binding grasses along banks and slopes which are prone to rapid erosin. 8. Afforestation or reforestation should be done. Thermal pollution Thermal pollution is the act of altering the temperature of a natural water body, which may be a river, lake or ocean environment. This condition chiefly arises from the waste heat generated by an industrial process such as certain power generation plants. The concept is most frequently discussed in the context of elevating natural water temperature, but may also be caused by the release of cooler water from the base of reservoirs into warmer rivers. Elevated river temperatures can also arise from deforestation or urbanization that can reduce stream shading. Thermal pollution is one parameter of the broader subject of water pollution. There can be significant environmental consequences of thermal pollution with respect to surface receiving waters such as rivers and lakes; in particular, decrease in biodiversity and creation of an environment hospitable to alien aquatic species may occur. Regulation of thermal pollution has been more elusive than for other forms of water pollution, although straightforward
  26. 26. mitigation measures are available, especially in the case of elevated temperature discharges. Causes/Sources of thermal pollution: Industrial Effluents- Industries require cooling water for heat removal and cooling purposes. This heated water when discharged into the water system increases the temperature of water body. Nuclear Power plants-Nuclear power plants emit large quantity of heat and traces of radioactive substances which increases the temperature of water bodies. Coal- fired power plants- It is one of the major source of thermal pollution. Domestic sewage-When the domestic sewage is disposed off into water bodies like river, lakes etc it increases the temperature of receiving water. Radioactive waste- Dumping of radioactive waste in marine system increases the temperature when these substances radiate energy. Effects of Thermal pollution: There are two types of effects of thermal pollution Thermal shock: Due to decrease in DO levels there is suffocation of plants and animal species which creates anaerobic conditions .The sudden change in the temperature causes harm to the aquatic organisms. Thermal enrichment: The heated water is used for irrigation purposes to extend plant growing seasons. The warmer water also increases the metabolic rate of aquatic organisms (which in turn decreases the life expectancy of these organisms). The speedy growth is beneficial for commercial purposes. Mitigation There are several means of reducing impacts of warm water termal discharges, including use of cooling ponds, cooling towers and also productive use of the heated water for a secondary industrial process or space heating. In the
  27. 27. case of cold water discharge from reservoir bottoms, the mitigation is not as straightforward, and can often be very expensive. Since there are seasonal variations in the degree of vertical thermal stratification, the timing of water releases can sometimes be conducted to minimize cold water differents in the discharge, provided these releases are consistent with needs for flood control or power generation. In the summer, for example, there may be extremes in formation of cold water layers at the reservoir bottom; such times would be adverse for cold water release impacts downstream. Regulation Some countries and even individual states and provinces require limits on discharges that lead to thermal pollution of receiving waters. although this aspect of water pollution has proven to be more elusive than conventional chemical discharge. In many cases regulation has come about through judicial application of the United States Clean Water Act and other statutes. For example, in a state statute challenge the court found that anticipated thermal pollution impacts were sufficient grounds to reverse approval of construction of two nuclear power plants. Regulation may take very different approaches; in some laws, a best practice is required, such as the use of cooling ponds or cooling towers for waste heat discharge. In other cases, a numerical limit on acceptable temperature increase in the receiving waters is applied. For example, the World Bank standard provides a maximum increase of three degrees Celsius at the margin of the mixing zone.