Environmental Pollution Control

Environmental Pollution Control CHE F411

BITS Pilani BITS Pilani Pilani Campus

Ajaya Kumar Pani

Department of Chemical Engineering B.I.T.S-Pilani, Pilani Campus

Lecture-1 02-08-2017 BITS Pilani BITS Pilani Pilani Campus

Lecture-1 02-08-2017 BITS Pilani BITS Pilani Pilani Campus

Introduction BITS Pilani BITS Pilani Pilani Campus

CHE F411Environmental Pollution Control

Air pollution deaths expected to rise because of climate change Don’t drink from these polluted Bengaluru rivers! (1st August)

SC seeks clarity on pollution from crackers (30 th July) Doctors to educate patients on pollution (29th July) Underweight, premature infant birth has another reason – Pollution (28th July) Pay Rs 10 lakh for pollution in Mathura: NGT to Cantonment Board (26th July)

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Introduction • “Nature has enough for satisfying everybody’s need but not for anybody’s greed”. • Desire for more and more comfort • Nature has created the coal and petroleum in millions of years and we have exhausted them in hundreds of years. • In the last 300 years we have consumed most of the coal and almost all of the petroleum products. • Out of the 1,30,000 MW installed capacity of electricity production in India about 66% is by fossil fuels (coal+ petroleum products), 24% by hydropower, 4% by nuclear means and only 6% by renewable energy resources like solar, wind, biomass including small hydropower plants 8 October 2017

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ENERGY CONSUMTION AND DEMAND Improvements in technology for discovery and utilization of fossil fuels. Two main reasons for this growth in energy consumption •

Exponential growth of world’s population

•

Per capita energy consumption rate which is also exponential

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Acid Rain Acid rain" is a popular term referring to the deposition of wet (rain, snow, sleet, fog, cloudwater, and dew) and dry (acidifying particles and gases) acidic components.

Distilled water, once carbon dioxide is removed, has a neutral pH of 7. Liquids with a pH less than 7 are acidic, and those with a pH greater than 7 are alkaline. "Clean" or unpolluted rain has an acidic pH, but usually no lower than 5.7, because carbon dioxide and water in the air react together to form carbonic acid, a weak acid according to the following reaction: H2O (l) + CO2 (g) H2CO3 (aq) H ++ HCO3 •

Carbonic acid is a weak acid and the acidity in rainwater can be quickly neutralized in contact with materials. But the presence of sulphuric acid or nitric acid in the atmosphere can lower the pH of rain droplers below 5.6 and such rain is considered as acidic It can affect biota of aquatic ecosystem { limited carbonate-bicarbonate natural buffering capacity}

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Greenhouse effect • • •

• • •

The Earth receives energy from the Sun in the form UV, visible, and near IR radiation most of the radiation passes through the atmosphere without being absorbed or reflected. Of the total amount of energy available at the top of the atmosphere (TOA), about 26% is reflected back out to space by the atmosphere and clouds and 19% is absorbed by the atmosphere and clouds. Most of the remaining energy is absorbed at the Earth's surface. The surface radiates thermal radiation that consists of wavelengths that are much longer than the wavelengths that were absorbed Most of this thermal radiation is absorbed by the atmosphere, thereby warming it The atmosphere radiates energy both upwards and downwards; the part radiated downwards is absorbed by the Earth's surface. This leads to a higher equilibrium temperature than if the atmosphere were absent.

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By their percentage contribution to the greenhouse effect on Earth the four major gases are • water vapor, 36 –70% • carbon dioxide, 9 – 26% • methane, 4 –9% • ozone, 3 –7%

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Carbon Emissions and Global Warming Climate change and increasing concentrations of the so called greenhouse gases CO2 CH4 , N2O, O3 and chlorofluorocarbons (CFC’s ) in the atmosphere due to human activities are reasons for environmental problems These gases magnify the natural green house effect and will increase the formation of water vapor thus enhancing the warming trend ozone, nitrous oxide and CFC are now banned by international treaty because of their damaging effect on earths protective ozone layer.. But in India it is still in use Energy and related activities contribute 50% and industry has share of 24% •

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Carbon Emmissions and Global Warming Impact : Global avg tem to increase by 0.3 deg C per decade in next 100 yrs Severe climatological changes

Alter the sea level , ( thermal expansion of earth surface and rapid melting of galciers and ice caps) US EPA- anywhere from 1 and half meter by 2100 with diastrous consequences Low lying countries such as bangladesh and netherlands would be devasted by such rises Eastern Himalays glaciers will vanish by 2035 Rising sea water- Cascading effects

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Reduction in Carbon Emissions Control strategy to reduce the emissions Carbon emissions: 1989- 5764 million tonnes Projected to double by 2020 if the current trend is maintained

To stabilize the Concentration of CO 2 SCIENTIST BELIEVE TO CUT THE Global emissions by 2 billions tonnes annually ---Use of coal curtailed by 90% ----Oil by 50%

Technologies to be used : Energy efficient technology, combined cycle (25%), forest related technologies bomass ased, solar-thermal and solar-photovoltaic technologies

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Impact of Urban Areas Impact of Hydroelectric and Nuclear Energy: Worlds Hydroelectric power production is half that of produced by fossil fuels . Industrial developed regions of Africa, South America and south east Asia which represent 60% of world total India- 41000 MW ( more than 50% of total potential) Construction of large dams affects hydrology, terrestrial system and aquatic system, salinity, turbidity reduction, serious depletion of fisheries

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Impact of Urban Areas Nuclear Energy: 3 % of India Electricity generations

Ambitious plans to have installed nuclear capacity of 10000 MW by year 2000 ( not realized) Uranium reserves in India are 67000 tonnes of U 3O8 13000 present in monazite sands

Advantage: Air pollution is less, radioactive emissions can be kept very low Land use optimum (1/17 of required for coal – Uranium ) Fear

Radiation hazard its decay

, inhalation of products,

radon

gas

and

this cause cancer, genetic damage) 22

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Chemical Pollution 5 million chemicals have been synthesized in the world in last 40 years They are synthesized without proper technological and toxicology reports

Steel, non ferrous metals fertilizers and petroleum are the sources of lead, zinc arsenic, nickel, beryllium and mercury. Greater threat to environment than SO 2 Arsenic occurs in phosphate rock

Slowly accumlates in the body and excreates slowly Zinc toxicity is iron deficiency anaemia

Indiscrimate use of DDT…links to food chaib and accumulate in human body Pesticide residues are in all varieties of food like milk, fish, fruits and vegetables

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Marine Pollution Human activities include 75% of marine pollution worldwide Entry sources such as sewage, forestry and pathogens, heavy metals

50% of oil pollutions comes from land as runoff from cars, heavy machineries and industries The discharge of nutrients and sediments into the sea cause algal blooms, deplete water of oxygen impede photosynthesis Destroy marine lifes

Spread diseases like cholera and typhoid. Pesticides cause disease in fish. DDT and fat soluble toxicants are way up in the food chain and accumulate in the fat of marine animals

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Ozone Depletion Ozone layer in the stratosphere serves as a shield protecting the earth surface from the sun’s deadly ultraviolet radiation . As ozone absorbs UV radiation it is broken down into oxygen molecule and an electronically excited oxygen radical. The oxygen molecule and oxygen radical then recombine to form a new ozone molecule available to absorb more UV radiation. Chlorofuorocarbons (CFC) when used in air condition and refrigeration were valued for their stable and non toxic properties. The highly stable CFC produced in lower troposphere pass the zone without any change and reach

stratosphere. Here they are impacted by UV radiation and release destructive chlorine atoms

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Ozone Depletion Cl +O3→ClO+O2(step 1)

• ClO+O.→Cl +O2(step 2)

The above reaction also removes oxygen radical thus preventing it from recombining As seen there is no net consumption of Cl atoms and merely act as a catalyst for the

reaction. Thus one atom can convert many ozone molecules to ordinary oxygen molecules before ultimately forming a stable product . Reactions are actively swift Downward trend due to international regulations New Processes such as HCFC and HFC (as sunstitutes much lower affect or zero affect)

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Environmental disasters • Chernobyl • Bhopal • Kuwaiti Oil Fires • Love Canal • The Exxon Valdez • Tokaimura Nuclear Plant • The Aral Sea • Seveso Dioxin Cloud • Minamata Disease • Three Mile Island 8 October 2017

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Pollution Control Authorities MOEF CPCB SPCBs NGT

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• Systematic pollution of our environment is one of the biggest hazards faced by humanity today • Task of preserving the purity of environment is of utmost significance • Two most pressing demands are (1) protection of environment (2) efficient use of natural resources • There is need of technical manpower who could develop and implement effective means for protecting the environment

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Environmental engineering • The application of science and engineering principles, under constraint, to the protection and enhancement of the quality of the environment and to the enhancement and protection of public health and welfare

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What kinds of pollution are there? Water

Pollution

Solid Waste 8 October 2017

Air 23


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Course outline •To understand the challenges of air borne pollutants and master the methods to control them •To understand the challenges of water borne pollutants and master the methods to control them •To understand the challenges of solid waste and master the methods to control them •To acquire skill in designing and/or capacity enhancement of air pollution control equipments, water treatment processes, solid waste disposal and control processes •To become aware of the various Indian laws and regulation related to pollution control

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Course outline Text Book T1. Davis, M. L. and D. A. Cornwell, “Introduction to Environmental Engineering”, McGraw Hill, New York, 5th ed., 2013. T2. Rao, C.S., Environmental Pollution Control Engineering, New Age International 2nd Ed., 2006. Reference Books R1. Sincero A. P., Sincero G. A., Environmental Engineering: A Design Approach, PHI, 1996. R2. Peavy, H.S., Rowe, D.R. and Technobanolous , G., “Environmental Engineering” McGraw Hill, 1985. Research papers from different journals 8 October 2017

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Course outline Module No

Lecture Session

L1.1 Introduction, global warming, green house effect, climate change, river pollution etc. Significance of Environmental Engineering course, Handout discussion

Referen ce

Learning Outcome

Ch. 9, T1 Ch. 1, T2

To know the different types of air pollutants, their sources & effects. Awareness about the Air act

1. Introduction, Air pollution: sources & effects

L1.2 Definition and Scales of Concentration , Classification and Properties of Air Pollutants Emission Sources

L1.3 Effects of air pollution, The air act 8 October 2017

Ch. 2 T2

Ch. 2 T2 28


Course outline L2.1 Types of pollutant sampling and measurments, Ambient Air Sampling 2. Air pollution sampling & measurement

L2.2 Stack Sampling, Analysis of Air Pollutants L3.1 Temperature Lapse rate and Stability L3.2 Wind Velocity and Turbulence, Plume Behaviour L3.3 Dispersion of Air Pollutants

3. Meteorological aspects of air pollutant dispersion

L3.4 Estimation of Plume Rise

Ch. 3, T2

To study the types of air pollutants sampling & measurement.

To study the meteorological conditions prevailing in the atmosphere, which affect the dispersion of Ch. 9, T1 pollutants Ch. 4 T2 emitted into the atmosphere.

L3.5 Application of Gaussian Plume model for estimating pollutant concentration at any place

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Course outline L4.1 Types of control, efficiency calculation, various types of particulate emission control methods

To study different control methods for removal of particulates from air.

L4.2 gravity settling chamber, cyclone separator L4.3Bag filter, electrostatic precipitator 4. Air pollution control methods and equipment

L4.4 Gaseous pollutant removal: Absorption

Ch. 9, T1 Ch. 5 T2

L4.5 Gaseous pollutant removal: Adsorption, combustion L4.6 Gaseous pollutant removal (centrifugal and venturi scrubber) L4.7 Control of specific gaseous pollutants (SOx, NOx, CO) 8 October 2017

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Course outline To know the different types of water pollutants & their effects.

L5.1 Water Resources, Origin of wastewater, Types of Water Pollutants and their effects

5. Sources & classification of water pollutants

L5.2 Dissolved oxygen estimation, DO sag curve L5.3Ultimate BOD determination using Thomas method

Ch. 7, T1 Ch 6 T2

L5.4 Types of water pollutants, The water act To study the different methods of analysis of water pollutants.

L6.1 Sampling, Method of Analysis(Understanding of concepts of DO, BOD, COD, TOC) L6.2 analysis of DO, BOD, COD, TOC 6. Wastewater sampling and analysis

Ch 7, T2

L6.3 Determination of Inorganic Substances, Physical Characteristics, Bacteriological Measurements, Water Quality Standards To study the primary, secondary and advanced treatment methods for water and wastewater.

L7.1 Basic Processes of Water Treatment, Pretreatment, Screening, Sedimentation,

7. Wastewater treatment

L7.2 Discrete settling phenomenon, design of sedimentation tank L7.3 biological treatment, study and design of activated sludge process L7.4 zone settling process, design of secondary clarifier

Ch. 8, T1

L7.5 ultrafiltration, microstraining, adsorption L7.6 Reverse osmosis, ion exchange

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L8.1 Solid waste: Sources and Classification, Public Health Aspects, Methods of Collection, Disposal Methods, Potential Methods of disposal

11, T1

L8.2 Hazardous Wastes : Definition and Sources, Hazardous Waste Classification

8. Solid and Hazardous waste management

L8.3 Potentially Non Compatible Wastes, Hazardous Waste Management Strategy, Treatment Methods, Solidification and Stabilization

Ch 12 T1

To know the sources of solid wastes, their types, effects, methods of collection & methods of disposal. To study hazardous waste management including radioactive waste management.

L8.4 solid waste management regulation, hazardous waste management regulation L8.5 Basics of radioactivity & radiation, effects of radiation and protection methods L8.6 types of radioactive wastes, disposal methods L 9.1 characteristics of sound wave, sources of noise, effects 9. Noise pollution

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L9.2 measurement of noise, control techniques, noise regulation act

Ch. 11, T1 Ch. 11, T1

Ch.10, T1

To know the sources of noise pollution, its effects, measurement of noise & control techniques for noise pollution.

32


Evaluation Scheme EC No.

Evaluation Component

1.

Surprise Quizzes

2.

Assignments/Semi nar

3.

Mid Semester Test

4.

Comprehensive Exam.

8 October 2017

Weightage Duration

During lecture hour

Date, Time & Venue

% (Marks)

Nature of Component

16

CB*

14

**

90 min

30

3 hr.

40

-

CB and/or OB CB and/or 33

Environmental Pollution Control

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