industrial pollution and control

Subject : Industrial Pollution and Control [Theory] Branch: Metallurgy

Semester: 5th

Faculty: Mr. Vikram Singh Nanda Code: 338512 (38)

Department of Metallurgy, OPJIT, Punjipathara, Raigarh [C.G]

Class Lecture Notes of Unit-1

[Classification of pollutants]

Subject: Industrial Pollution and Control

[Theory - 338512 (38)]

Branch: Metallurgical Engineering Semester: 5th

Faculty: Mr. Vikram Singh Nanda

Classification of pollutants: Sources, Ecological Imbalance

� Biodegradable and non-biodegradable pollutants

� Review of Metal Pollution [Arsenic, Cadmium, Lead, Mercury]

� Review of Water Pollution

� Review of Sound Pollution

� Review of Air Pollution

� Review of Solid Waste Pollution

� Review of Thermal Pollution

� Review of Radiation Pollution, and Noise Pollution!


Semester: 5th



Pollution and pollutants The change (disturbance) in any component of the environment which leads to its deterioration is termed as pollution of the environment. It is the undesirable change in the physical or biological components which adversely alters the environment. Pollutants: The substance which is present in harmful concentration and is the agent who causes pollution is termed as the pollutant. CLASSIFICATION OF POLLUTANTS: On the basis of existence in nature

• Quantitative Pollutants- The substances which are already present in the environment, but are termed as pollutants when their concentration (quantity) increases in the environment. eg. CO2 is present in the environment in greater quantity than normal and is hence termed as a quantitative pollutant.

• Qualitative pollutant- The substances which are not normally present in the environment and are added by human beings and are pollutants by nature. Eg. insecticides, pesticides

On the basis of the form in which they persist

• Primary Pollutants- The substances which are directly emitted from the source and remain in that form are termed as primary pollutants eg, smoke, fumes, ash, dust, nitric oxide and sulphur dioxide

• Secondary pollutants- The substances which are formed by chemical reaction between the primary pollutants and constituents of the environment (i.e. those which are already present in the environment) .eg smog, ozone, sulphur trioxide, nitrogen dioxide.

On the basis of disposal

• Bio-degradable pollutants- the pollutants which are decomposed by natural processes eg domestic (municipal) sewage.

• Non bio-degradable pollutants- The pollutants which don’t decompose naturally or

decompose slowly eg DDT, aluminium cans.


Semester: 5th



Biodegradable pollutants

Pollutants that can be used and decomposed by microbes, insects or other animals and birds are called biodegradable pollutants. Examples of biodegradable pollutants are excreta [Waste matter (as urine or sweat but especially stool) discharged from the body], organic wastes, paper, leftover food etc. Biodegradable pollutants can be converted into harmless products through biological activities. Biodegradable means that by microorganisms something must turn back into

naturally occurring minerals, usually co2, ch4, dirt (humus - Partially decomposed

organic matter; the organic component of soil) water.

Biodegradable waste can be commonly found in municipal solid waste (sometimes

called biodegradable municipal waste, or BMW) as green waste, food waste, paper

waste, and biodegradable plastics. Other biodegradable wastes include human

waste, manure, sewage, slaughterhouse waste. In the absence of oxygen much of

this waste will decay to methane by anaerobic digestion.

The main environmental threat from biodegradable waste is the production of

methane in landfills. Methane is 21 times as potent a greenhouse gas as carbon

dioxide and accounted for some 3% of total greenhouse gas emissions in the EU-15

in 1995.

There is concern that greenhouse gas, methane, might be released when any

biodegradable material, including truly biodegradable plastics, degrades in an

anaerobic [Living or active in the absence of free oxygen] or landfill environment.

Methane production from landfills is rarely captured or burned, but it rather enters the

atmosphere, where it is a potent greenhouse gas.

Methane production from specially managed landfill environments is captured and

used for energy or burnt off to reduce the release of methane in the environment.

Most landfills today capture the methane biogas for use in clean inexpensive energy.

Of course, incinerating non-biodegradable plastics will release carbon dioxide as

well. Disposing of biodegradable plastics made from natural materials in anaerobic

(landfill) environments will result in the plastic lasting for hundreds of years.

Is cloth biodegradable or non-biodegradable? : - It depends on what the cloth is

made of.

Non-Biodegradable pollutants:

Pollutants that cannot be converted to harmless products through natural activities are called Non- Biodegradable pollutants. Examples of Non-Biodegradable pollutants are plastic, polythene etc. Depending on physical state, these Non-Biodegradable pollutants can be (1) gaseous (2) solid (3) liquid or (4) suspended substances.


Semester: 5th



Non-biodegradable implies that the material is totally immune from attack by any

biological/natural elements and therefore, will exist forever in essentially the same

form for ever.

Bio-degradable pollutants can be broken down by living organisms where as non-

biodegradable cannot be broken down back into the soil.

In general, differences are based on whether or not the action of "a biological agent"

can cause the waste in question to be "degraded" to some acceptable level.

Biodegradable means that natural processes can break down the material into their

natural components. Whereas, non-biodegradable materials would not be affected

by natural processes that would break the material down. Plastic usually is non-

biodegradable, because there are very few natural processes that could break the

plastic down into smaller elements, whereas something like wood will rot and decay

and be recycled back into the soil.

Biodegradable implies that the material will be destroyed / dissembled by biological

and/or natural elements. Nitric Acid rain manufactured in thunderstorms , Oxygen in

the air, ultraviolet light in sunlight, and all kinds of microscopic "critters [“creature”

especially living-organisms] in the atmosphere and soil which "chomp” [chewing off]

on all kinds of materials [including some petroleum products].

Biodegradable wastes decompose into soil.

• Kitchen food scraps • Garden waste • Paper and egg shells • Human and animal waste • cardboard boxes

Non-biodegradable wastes take a long time or never to decompose.

• metal cans • bottles • toxic chemicals • plastic products • metal scraps

Municipal solid waste (MSW), commonly known as trash or garbage is a waste type consisting of everyday items we consume and discard. It predominantly includes food wastes, yard wastes, containers and product packaging, and other miscellaneous inorganic wastes from residential, commercial, institutional, and industrial sources. Examples of inorganic wastes are appliances, newspapers, clothing, food scrapes, boxes, disposable tableware, office and classroom paper, furniture, wood pallets, rubber tires, and cafeteria wastes. Municipal solid waste does


Semester: 5th



not include industrial wastes, agricultural wastes, and sewage sludge. The collection is performed by the municipality within a given area. They are in either solid or semisolid form. The term residual waste relates to waste left from household sources containing materials that have not been separated out or sent for reprocessing. Following are the different types of wastes.

• Biodegradable waste: food and kitchen waste, green waste, paper (can also be recycled).

• Recyclable material: paper, glass, bottles, cans, metals, certain plastics, etc. • Inert waste: construction and demolition waste, dirt, rocks, debris. • Composite wastes: waste clothing, Tetra Packs, waste plastics such as toys. • Domestic hazardous waste (also called "household hazardous waste") & toxic

waste: medication, e-waste, paints, chemicals, light bulbs, fluorescent tubes, spray cans, fertilizer and pesticide containers, batteries, shoe polish.

The chief causes of pollution are industrialization and urbanization. Various

pollutants pollute the atmosphere. These pollutants adversely affect the life of

organism [A living thing] directly or indirectly. These pollutants accumulate in the

body and spread in the food web. On the basis of medium in which pollutants

spread, pollution can be classified into three types. (1) Aerial pollution (2) Aquatic

(water) pollution (3) Terrestrial [Land] pollution.

MAINTENANCE OF ECOLOGICAL BALANCE IN NATURE Ecological balance The rich diversity of life that inhabits the earth helps in maintaining a balanced environment. The perfect balance between the physical environment and the living organisms in nature is called ecological balance. Herbivores eat plants, and are themselves eaten by carnivores. The number of plants, herbivores and carnivores is maintained in such a way that there are enough organisms of different species to survive. However, various human activities cause interference and imbalance in nature. Ecological imbalances may lead to: • Destruction of natural habitat of wild life. For example, cutting of forests have resulted in the disappearance of Cheetah, and a falling number of tigers in India. • Addition of various chemicals from industries in the Kalu River near Bombay has resulted in extinction of the Bombay duck, a favorite fish of the people living in this area. • Capturing or killing of lions has led to an increased number of herbivores that compete for grass. They may uproot grass, making the soil barren that may lead to soil erosion and desertification. • Disturbance in the food chain, which has resulted in an enormous increase in the population of a particular types of organisms, while others may become endangered. Impact of human population on the environment The population of India has crossed the figure of 1 billion and the world population is estimated to have touched the 6 billion mark. To meet the demand of food, housing and energy, environmental resources are being exploited at a fast pace.


Semester: 5th



Environment has the potential to replenish most of its resources in a certain period of time. However, over-exploitation of resources and human activities have altered it leading to many environmental problems, such as: • Deforestation, • Destruction of wild life, • Air, water and land pollution, • Diminishing fossil fuels (oil, coal and natural gas), • Concentration of pesticides in alarming proportions in organisms, and • Depletion of ozone layer and global warming.


Semester: 5th



REVIEW of Air Pollution:


Semester: 5th




Semester: 5th



Evidence for Global Warming and Greenhouse effect

• The 20

th century was the warmest century in the past 1000 years.

• 2005 was the warmest year on record

• Mean global temperature rose about ½ º C (1 ºF) in past 100 years

• Increased frequency of hurricanes

• Methane levels have risen 145 % [Fig 1 below]

Figure 1: Global concentration of methane gas over the past 1000 years indicates a dramatic increase

beginning about 100 years ago. The data was obtained from air bubbles trapped in ice in Greenland.

• Since industrial revolution in 19th

century, CO2 concentrations have risen

34 %, highest in 650,000 yrs [Fig 2 is country wide CO2 emission plot]

• Rising sea temperatures

• Last century, the world’s sea level rose by 10-20 cm

• Disappearing glaciers

• Melting Arctic sea ice

• Melting Antarctic sea ice

Figure2 : Annual per capita carbon dioxide (CO2) releases for the 15 countries with the highest total

emissions, 2000. (1 metric ton = 1000 kg


Semester: 5th



Review of Solid Waste Pollution

Municipal solid waste (MSW) is the waste we know best. However, MSW is

only one among many wastes: construction and demolition debris, municipal

sludge, combustion ash, mining and drilling debris, agricultural wastes,

industrial process wastes including sludge, hazardous waste, and others.

There are several methods currently in use for disposal of solid waste. These

methods include landfills, incinerators, and recycling. In the United States,

less than 10% of solid wastes are recycled, more than 5% are incinerated, and

80% are disposed of in landfills (Environmental Task Force, 1986).

What is in Municipal Solid Waste and who produces it ?

Household waste contains anything that we choose to discard, including still

usable and recyclable items: waste food, papers and news papers , packaging,

bottles, metal cans, batteries, grass clippings and other yard waste, clothing,

furniture and appliances, paint and other discarded household chemicals; the “

other ” category includes appliances (white goods) , furniture, batteries, and

household hazardous waste (HHW) . HHW includes residual paints, oily

product s such as automotive maintenance products, and pesticides.

For many years paper has been the largest proportion of MSW in the United

States, about 34% by weight in 2006. This figure shows only what the US

federal government views as MSW. Some states also consider construction and

demolition debris to be MSW, where it equals about 12% by weight. And some

communities consider other wastes as MSW, which may include sludge from

drinking-water treatment and wastewater treatment plants, septic tank sludge,

medical and slaughter house waste, and fast -food grease. Households are only

one contributor to MSW. Others are institutions such as hospitals, government

offices, schools, and prisons; and commercial businesses including restaurants,

grocery stores, and offices. Industries too generate MSW.

Landfills

When we "throw away" something, it does not just "go away" – most of it goes

into a landfill. A sanitary landfill is a site where solid waste is disposed on land

to prevent public health and safety hazards. Landfills have strict guidelines for

placement. They must be constructed in areas where the possibility of

contamination if groundwater will be minimal, with a series of pipes to remove

leachate beneath a clay liner. Garbage must be compacted and covered with six

inches of soil daily, and land must be reclaimed as landfill operations are

completed.


Semester: 5th



Landfills are running out of room. Landfills are becoming "landfulls". Each day

Americans throw away 400 million pounds of food, junk 20,000 cars and

discard 18,000 TV's. The United States has 5% of the world population, but it

produces 30% of the world's garbage.

Leaks from landfills can contaminate groundwater. These are called leachates,

which are liquid wastes and can be formed when water mixes with buried waste.

Leachates may contain a variety of hazardous materials, including household

hazardous wastes.

Incineration

Incineration (the burning of waste) reduces the amount of waste by about 30 –

40%. With recycling, incineration can at best reduce the amount of waste by

about 80%. Incinerators can also be used to produce lasting electricity, by

generating steam with the burning waste, and using the steam to turn turbines.

There are concerns about the need for air pollution controls to keep particulate

matter from escaping into the air. Also, the ash remaining must be buried in a

landfill, and this residue often contains toxic metals and dioxins, which are

classified as hazardous wastes.

Recycling and the Need for Resource Recovery

Natural resources contained in wastes are growing more limited and more

expensive. We can no longer afford to waste energy or to discard valuable

resources that are still usable.

The Three R's

Reduce. Everyone can help reduce the amount of waste produced in this

country. Buy products that last longer, and only buy the amount of a product

needed for the job. Support businesses that use less packaging.

Reuse. Reuse products instead of buying new ones, and swap with others

products that are no longer being used.

Recycle. Take paper, cardboard, used motor oil, batteries, certain plastics,

construction materials, etc. to recycling centers. Compost [collect and convert to

fertilizer] kitchen scraps and yard wastes.

Recycling Paper

• Recycling old paper uses 50% less energy compared to making paper from

trees.


Semester: 5th



• Each ton of paper that is re-cycled replaces and preserves an acre of

harvestable trees.

Recycling Aluminium and steel cans:

• Making aluminum out of recycled aluminum uses 95% less energy than

making aluminum from bauxite ore, yet only 54% of all aluminum cans

were recycled in 1981. In other words, Aluminium recycling has major

environmental advantages – it uses up to 95% less energy than mining

it from bauxite, and reduces air and water pollution about the same

amount. Meanwhile, 3% of the world’s electricity goes into making new

aluminum cans and about a third of that electricity is generated from coal-

burning power plants.

• Steel cans: Recycling steel cans reduces energy consumption about 60%

compared to starting with raw materials. Both bauxite mining for

aluminum and iron mining for steel can be highly polluting and also

result in major land degradation in the area where mining occurs. These

are also called tin cans because some are still tin coated.

USA Municipal Solid Waste Distribution:

Fig: Materials in US MSW (2007) (254 million tons or 230 million tonnes before recycling)


Semester: 5th



Why does Municipal Solid Waste concern us?

Almost any garbage is unpleasant. It has unpleasant odours. Diapers and other

sanitary items have microorganisms, sometimes pathogens. So do rotting food

and yard wastes. ▪ Although HHW is only a small part of MSW, it can pose

problems such as catching on fire, or injuring the skin or eyes of workers

coming in contact with it, or breathing its fumes. However, a material need not

be hazardous to present problems.

Large quantities of packaging are generated: its composition may make it

difficult to recycle, or prevent it from biodegrading. And if it contains even

trace amounts of hazardous metals, expensive controls are necessary to prevent

metal emissions if it is incinerated.

Some MSW, once disposed of in a landfill may last indefinitely. Even dumped

in the open environment where there is sunlight, heat, and water, many items –

especially plastics – are long lived as shown in following fig.

Litter at the roadside is ugly, and dangerous to some wildlife. How long will it

stay before decaying may be an ugly surprise as shown in above figure.


Semester: 5th



Review of Thermal Pollution

Thermal Pollution is the increase in the normal temperatures of natural waters

caused by intervention of human activities.

Major Causes

Nuclear power plants

Deforestation

Soil erosion

Greatest source of heated water is from steam electric generating stations

Figure: Block diagram of a fossil-fueled electric generating station.

Nuclear Power Plants

Nuclear power plants use water as a cooling agent. After the water is used, it is

put back into a water supply at 9-20oC warmer

Effects of Increased Water Temperature

� Thermal shock – aquatic life adapted to a certain water temperature can

go into shock when the temp is changed even 1 or 2 degrees C.

� Oxygen dissolved in water decreases

� Increases the rate of photosynthesis, which increases the amount of plant

growth, developing eutrophic conditions


Semester: 5th



� Increases the metabolic rate of fish, which increases their need for oxygen

Biotic Effects of Thermal Pollution

� Changes in the environment may also result in a migration of organisms

to another, more suitable environment and to in-migration of organisms

that normally only live in warmer waters elsewhere. As a result one has

the problem of compromising food chains of the old and new

environments. Biodiversity can be decreased as a result.

� Changes of even one to two degrees Celsius can cause significant

changes in organism metabolism and other adverse cellular biology

effects. Principal adverse changes can include rendering cell walls less

permeable to necessary osmosis, coagulation of cell proteins, and

alteration of enzyme metabolism. These cellular level effects can

adversely affect mortality and reproduction.

� Growth & reproduction very sensitive to temperature

Under Drought Conditions

� Less water is absorbing more heat.

� Water flow is lower and slower.

� Insufficient water to function as a heat exchanger.

� Water gets hotter.

Deforestation

� The decrease in vegetation increases the amount of light that hits the

water, which increases the temperature of the water

� Deforestation also increases Soil Erosion. Erosion makes the water

muddy, which decreases the light absorbed.

Possible Solutions of Thermal Pollution

� Energy alternatives

� Desalination plants

� Less nuclear power

� End shoreline deforestation

� Prevent soil erosion


Semester: 5th



REVIEW OF Radiation POLLUTION

Radiation occurs when unstable nuclei of atoms decay and release

particles. There are many different types of radiation. When these

particles touch various organic materials such as tissue, damage

may, and probably will, be done. Radiation can cause burns, cancers,

and death.

Three Types of Radioactive Decay

There are three main types of radiation:

o Alpha radiation o Beta radiation o Gamma radiation

Units of Measurement

The unit used to measure radiation dosage is the rem, which stands

for roentgen equivalent in man. It represents the amount of radiation

needed to produce a particular amount of damage to living tissue. The

total dose of rems determines how much harm a person suffers. At

Hiroshima and Nagasaki, people received a dose of rems at the

instant of the explosions, then more from the surroundings and, in

limited areas, from fallout. Fallout is composed of radioactive

particles that are carried into the upper atmosphere by a nuclear

explosion and that eventually fall back to the earth's surface.

Effects of Radiation Exposure on Human Health

Although a dose of just 25 rems causes some detectable changes in

blood, doses to near 100 rems usually have no immediate harmful

effects. Doses above 100 rems cause the first signs of radiation

sickness including:

� nausea

� vomiting

� headache

� some loss of white blood cells

Doses of 300 rems or more cause temporary hair loss, but also more

significant internal harm, including damage to nerve cells and the

cells that line the digestive tract. Severe loss of white blood cells,


Semester: 5th



which are the body's main defense against infection, makes radiation

victims highly vulnerable to disease. Radiation also reduces

production of blood platelets, which aid blood clotting, so victims of

radiation sickness are also vulnerable to hemorrhaging. Half of all

people exposed to 450 rems die, and doses of 800 rems or more are

always fatal. Besides the symptoms mentioned above, these people

also suffer from fever and diarrhea. As of yet, there is no effective

treatment--so death occurs within two to fourteen days.

In time, for survivors, diseases such as leukemia (cancer of the

blood), lung cancer, thyroid cancer, breast cancer, and cancers of

other organs can appear due to the radiation received.

Major Radiation Exposure in Real Life Events Case studies

Hiroshima and Nagasaki

For more information on what happened at Hiroshima and Nagasaki,

consult the nuclear past page and the nuclear warfare page.

Many people at Hiroshima and Nagasaki died not directly from the

actual explosion, but from the radiation released as a result of the

explosion. For example, a fourteen-year-old boy was admitted to a

Hiroshima hospital two days after the explosion, suffering from a

high fever and nausea. Nine days later his hair began to fall out. His

supply of white blood cells dropped lower and lower. On the

seventeenth day he began to bleed from his nose, and on the twenty-

first day he died.

At Hiroshima and Nagasaki, the few surviving doctors observed

symptoms of radiation sickness for the first time. In his book

Nagasaki 1945, Dr. Tatsuichiro Akizuki wrote of the puzzling,

unknown disease, of symptoms that "suddenly appeared in certain

patients with no apparent injuries." Several days after the bombs

exploded, doctors learned that they were treating the effects of

radiation exposure. "We were now able to label our unknown

adversary 'atomic disease' or 'radioactive contamination' among other

names. But they were only labels: we knew nothing about its cause or

cure... Within seven to ten days after the A-bomb explosion, people

began to die in swift succession. They died of the burns that covered

their bodies and of acute atomic disease. Innumerable people who had

been burnt turned a mulberry color, like worms, and died... The

disease," wrote Dr. Akizuki, "destroyed them little by little. As a


Semester: 5th



doctor, I was forced to face the slow and certain deaths of my

patients."

Doctors and nurses had no idea of how their own bodies had been

affected by radioactivity. Dr. Akizuki wrote, "All of us suffered from

diarrhea and a discharge of blood from the gums, but we kept this to

ourselves. Each of us thought: tomorrow it might be me... We became

stricken with fear of the future." Dr. Akizuki survived, as did several

hundred thousand others in or near Hiroshima and Nagasaki. In fact,

at least ten people who had fled from Hiroshima to Nagasaki survived

both bombs.

The survivors have suffered physically from cataracts, leukemia and

other cancers, malformed offspring, and premature aging, and also

emotionally, from social discrimination. Within a few months of the

nuclear explosions, leukemia began to appear among the survivors at

an abnormally high rate. Some leukemia victims were fetuses within

their mothers' wombs when exposed to radiation. One child who was

born two days after the Hiroshima explosion eventually died of acute

leukemia at the age of eighteen. The number of leukemia cases has

declined with time, but the incidence of lung cancer, thyroid cancer,

breast cancer, and cancers of other organs has increased among the

survivors.

Three Mile Island

For more information on what happened at Three Mile Island, consult

the nuclear past page.

On a Wednesday morning, maintenance workers cleaning sludge

from a small pipe blocked the flow of water in the main feedwater

system of a reactor at Three Mile Island near Harrisburg,

Pennsylvania. The sift foreman heard "loud, thunderous noises, like a

couple of freight trains," coming. Since the reactor was still

producing heat, it heated the blocked cooling water around its core

hot enough to create enough pressure to have popped a relief valve.

Some 220 gallons of water per minute began flowing out of the

reactor vessel. Within five minutes after the main feedwater system

failed, the reactor, deprived of all normal and emergency sources of

cooling water, and no longer able to use its enormous energy to

generate electricity, gradually started to tear itself apart.

The loss of coolant at the reactor continued for some 16 hours. Abort

a third of the core melted down. Radioactive water flowed through


Semester: 5th



the stuck relief valve into an auxiliary building, where it pooled on

the floor. Radioactive gas was released into the atmosphere. An

estimated 140,000 people were evacuated from the area. It took a

month to stabilize the malfunctioning unit and safely shut it down.

The reactor was a total loss and the cleanup required years of repair

and hundreds of millions of dollars.

No one was reported injured and the little radiation that leaked out

was quickly dispersed. Although this accident did cost lots of money

and time, no one was hurt.

Chernobyl Nuclear Power Station, USSR

I took this info from documentary on “Chernobyl disaster” in

Discovery channel dated 7th August 2011. – [Vikram Singh Nanda]

A far more serious accident occurred at Chernobyl, in what was then

still the Soviet Union. At the time of the accident, the Chernobyl

nuclear power station consisted of four operating 1,000 megawatt

power reactors. Without question, the accident at Chernobyl was the

result of a fatal combination of ignorance and mismanagement. "As

members of a select scientific panel convened immediately after the...

accident," writes Nobel laureate Hans Bethe, "my colleagues and

I established that the Chernobyl disaster tells us about the deficiencies

of the Soviet political and administrative system rather than about

problems with nuclear power."

Although the problem at Chernobyl was relatively complex, it can

basically be summarized as a mismanaged electrical engineering

experiment in night shift carried out by junior engineers [instead of

senior staff/scientists], which resulted in the reactor exploding due to

overheating [due to lack of cooling water circulation]. The explosion

was chemical, driven by gases and steam generated by the core

runaway, not by nuclear reactions. Flames, sparks, and chunks of

burning material [consists of Uranium and plutonium] were flying

into the air [1km high] above the unit. These were red-hot pieces of

nuclear fuel and graphite. About 50 tons of nuclear fuel evaporated

and were released by the explosion into the atmosphere. In addition,

about 70 tons were ejected sideways from the periphery of the core.

Some 50 tons of nuclear fuel and 800 tons of reactor graphite

remained in the reactor vault [underground chamber], where it

formed a pit of a volcanic crater as the graphite still in the reactor had

turned up completely in a few days after the explosion. Failure

analysis revealed the root cause of explosion was mismanagement


Semester: 5th



and wrong decision of carrying out experiment/test in night shift by

junior engineers. 8 senior engineers were held responsible for this

mismanagement and were rigorously punished for 10 years behind

bars.

The resulting radioactive release was equivalent to ten Hiroshimas. In

fact, since the Hiroshima bomb was air-burst--no part of the fireball

touched the ground--the Chernobyl release polluted the countryside

much more than ten Hiroshimas would have done. There was danger

of ground water contamination due to underground construction of

nuclear reactor. Soviet Union Army were called to clear the

contaminated debris and they were using heavy lead cloths and

individual army personal was not working more than 3 minutes in a

stretch. The whole explosion site was covered [with the help from

USA] with thick cemented slab in order to stop nuclear radiation

coming out from debris/underground site. Many people died from the

explosion and even more from the effects of the radiation later. Still

today, people are dying from the radiation caused by the Chernobyl

accident. The estimated total number of deaths will be 16,000.

Children were and still today suffering from thyroid cancer.

Medical Treatment of Radiation

For a more in-depth view of current medical technologies available to

the treatment of radiation, go to the medical imaging page

There is currently no effective medical treatment available for

potentially fatal radiation doses. The case of the Japanese boy

mentioned above illustrates an important fact about radiation

sickness. The boy had probably received a dose of 450 rems or more,

yet his symptoms were about the same as those of a person who

received about 300 rems. Medical science has no way of telling the

difference between people who have received fatal doses and will die

despite all efforts and others who received less radiation and can be

saved. Treatment for the ones that can be saved includes blood

transfusions and bone-marrow transplants. Bone-marrow transplants

rejuvenate the supply of white blood cells which was affected by the

radiation.


Semester: 5th



Review of Water Pollution

Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans

and groundwater). Water pollution affects plants and organisms living in these

bodies of water; and, in almost all cases the effect is damaging not only to

individual species and populations, but also to the natural biological

communities. Water pollution occurs when pollutants are discharged directly or

indirectly into water bodies without adequate treatment to remove harmful

compounds.

Water pollution is a major problem in the global context. It has been suggested

that it is the leading worldwide cause of deaths and diseases, and that it

accounts for the deaths of more than 14,000 people daily. An estimated 700

million Indians have no access to a proper toilet, and 1,000 Indian children die

of diarrheal sickness every day. Some 90% of China's cities suffer from some

degree of water pollution, and nearly 500 million people lack access to safe

drinking water. In addition to the acute problems of water pollution in

developing countries, industrialized countries continue to struggle with

pollution problems as well.

Water is typically referred to as polluted when it is impaired by anthropogenic

contaminants and either does not support a human use, like serving as drinking

water, and/or undergoes a marked shift in its ability to support its constituent

biotic communities, such as fish. Natural phenomena such as volcanoes, algae

blooms, storms, and earthquakes also cause major changes in water quality and

the ecological status of water.

Water pollution categories

Surface water and groundwater have often been studied and managed as

separate resources, although they are interrelated. Sources of surface water

pollution are generally grouped into two categories based on their origin.

Point source pollution Point source pollution refers to contaminants that enter a waterway through a

discrete conveyance, such as a pipe or ditch. Examples of sources in this

category include discharges from a sewage treatment plant, a factory, or a city

storm drain. The U.S. Clean Water Act (CWA) defines point source for

regulatory enforcement purposes. The CWA definition of point source was

amended in 1987 to include municipal storm sewer systems, as well as

industrial storm-water, such as from construction sites.


Semester: 5th



Fig: Point source pollution - Shipyard - Rio de Janeiro.

Non–point source pollution

Non–point source (NPS) pollution refers to diffuse contamination that does not

originate from a single discrete source. NPS pollution is often the cumulative

effect of small amounts of contaminants gathered from a large area. The

leaching out of nitrogen compounds from agricultural land which has been

fertilized is a typical example. Nutrient runoff in storm-water from “sheet flow”

over an agricultural field or a forest is also cited as examples of NPS pollution.

Contaminated storm water washed off of parking lots, roads and highways,

called urban runoff, is sometimes included under the category of NPS pollution.

However, this runoff is typically channelled into storm drain systems and

discharged through pipes to local surface waters, and is a point source. However

where such water is not channelled and drains directly to ground it is a non-

point source.

What are the sources of water pollution?

There are many causes for water pollution but two general categories exist:

direct and indirect contaminant sources.


Semester: 5th



Direct sources include effluent outfalls from factories, refineries, waste

treatment plants etc. that emit fluids of varying quality directly into urban water

supplies. In the United States and other countries, these practices are regulated,

although this doesn't mean that pollutants can't be found in these waters.

Indirect sources include contaminants that enter the water supply from

soils/groundwater systems and from the atmosphere via rain water. Soils and

ground waters contain the residue of human agricultural practices (fertilizers,

pesticides, etc.) and improperly disposed of industrial wastes. Atmospheric

contaminants are also derived from human practices (such as gaseous emissions

from automobiles, factories and even bakeries).

Causes of water pollution

The specific contaminants leading to pollution in water include a wide spectrum

of chemicals, pathogens, and physical or sensory changes such as elevated

temperature and discoloration. While many of the chemicals and substances that

are regulated may be naturally occurring (calcium, sodium, iron, manganese,

etc.) the concentration is often the key in determining what is a natural

component of water, and what is a contaminant.

Oxygen-depleting substances may be natural materials, such as plant matter

(e.g. leaves and grass) as well as man-made chemicals. Other natural and

anthropogenic substances may cause turbidity (cloudiness) which blocks light

and disrupts plant growth, and clogs the gills of some fish species. Many of the

chemical substances are toxic. Pathogens can produce waterborne diseases in

either human or animal hosts. Alteration of water's physical chemistry includes

acidity (change in pH), electrical conductivity, temperature, and eutrophication.

Eutrophication is an increase in the concentration of chemical nutrients in an

ecosystem to an extent that increases in the primary productivity of the

ecosystem. Depending on the degree of eutrophication, subsequent negative

environmental effects such as anoxia (oxygen depletion) and severe reductions

in water quality may occur, affecting fish and other animal populations.

What are the effects of water pollution?

The effects of water pollution are varied. They include poisonous drinking

water, poisonous food animals (due to these organisms having bio-accumulated

toxins from the environment over their life spans), unbalanced river and lake

ecosystems that can no longer support full biological diversity, deforestation

from acid rain, and many other effects. These effects are, of course, specific to

the various contaminants.


Semester: 5th



Groundwater pollution

Interactions between groundwater and surface water are complex.

Consequently, groundwater pollution, sometimes referred to as groundwater

contamination, is not as easily classified as surface water pollution. By its very

nature, groundwater aquifers are susceptible to contamination from sources that

may not directly affect surface water bodies, and the distinction of point vs.

non-point source may be irrelevant. A spill or ongoing releases of chemical or

radionuclide contaminants into soil (located away from a surface water body)

may not create point source or non-point source pollution, but can contaminate

the aquifer below, defined as a toxin plume. The movement of the plume, a

plume front, can be part of a Hydrological transport model or Groundwater

model. Analysis of groundwater contamination may focus on the soil

characteristics and site geology, hydrogeology, hydrology, and the nature of the

contaminants.

Measurement of water pollution

Water pollution may be analyzed through several broad categories of methods:

physical, chemical and biological. Most involve collection of samples, followed

by specialized analytical tests. Some methods may be conducted in situ, without

sampling, such as temperature. Government agencies and research organizations

have published standardized, validated analytical test methods to facilitate the

comparability of results from disparate testing events.

Physical testing

Common physical tests of water include temperature, solids concentration like

total suspended solids (TSS) and turbidity.

Chemical testing

Water samples may be examined using the principles of analytical chemistry.

Many published test methods are available for both organic and inorganic

compounds. Frequently used methods include pH, biochemical oxygen demand

(BOD), chemical oxygen demand (COD), nutrients (nitrate and phosphorus

compounds), metals (including copper, zinc, cadmium, lead and mercury), oil

and grease, total petroleum hydrocarbons (TPH), and pesticides.

Biological testing

Biological testing involves the use of plant, animal, and/or microbial indicators

to monitor the health of an aquatic ecosystem.

Debate: Waste is actually waste or waste is valuable?


Semester: 5th



HOW TO CONTROL POLLUTION PROBLEM ?

Science provides many practical solutions to minimizing the present level at

which pollutants are introduced into the environment and for remediating

(cleaning up) past problems. All of these solutions come with some cost (both

societal and monetary). In our everyday lives, a great deal can be done to

minimize pollution if we take care to recycle materials whose production

creates pollution and if we act responsibly with household chemicals and their

disposal. Additionally, there are choices we make each day that also can affect

the quantity of pollutants our actions will introduce into the environment.

Heavily packaged foods, for instance, contain boxes, cartons, bottles etc.. made

with polluting dyes, many of which are released from groundwater at municipal

landfills. Whether we choose to drive to the corner store rather than walk or ride

a bicycle will determine how much we personally contribute to acid and

hydrocarbon emissions to the atmosphere (and ultimately to global fresh water

supplies).

In the end, there are many choices on the personal and societal level that we

must make (consciously or not) that affect the amount of pollution our town or

country will be forced to live with. Our standard of living and very way of life

is based upon practices which are inherently "dirtier" than those of our distant

ancestors, although they too polluted their environment to some extent. Without

taking a step backward in terms of our standards of living, the answer seems to

lie in a combination of many small changes in our daily practices and paying

more for goods and services, so that manufacturers of various materials and

drivers of automobiles (for instance) will have cleaner devices with which to

conduct their activities.


Semester: 5th



Review of Sound / Noise Pollution


Semester: 5th




Semester: 5th



Summary of all types of Pollution for quick review


Semester: 5th



industrial pollution and control

Documents

primary pollutants

industrial pollution

g pollution

nature quantitative

noise pollution

metallurgy semester

department of metallurgy

control theory branch