environment is progressively degraded due to anthropological and disasters of management.

1. 8/21/2007
Lecture - 11
ENVIRONMENTAL POLLUTION
from
PROCESS INDUSTRIES
In this lecture Pollution -
Introduction by man, waste matter or surplus
Pollution and Pollutants energy into the environment, which directly or
indirectly causes damage to man and his
•
• Types of Pollution environment
• Effects of Pollution
• Managing Pollution
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The Issue
Pollutant - A substance or effect which
adversely alters the environment by changing
the growth rate of species, interferes with the • We use Resources extensively
food chain, is toxic, or interferes with health,
comfort amenities or property values of people and then are NOT responsible for
• The Consequences !!!
Aral Sea
Man made environmental
disaster
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EFFECTS ON BIOSPHERE
1. Damage to human health by specific
chemical substances present in the air, food, Pollution and effects
water and radioactive material
2. Damage to natural environment affecting
vegetation, animals, crops, soil and water
Minamata Disease
3. Damage to visual quality by smoke, fumes,
dust, noise and waste (Jinzu river, Japan)
4. Damage by carcinogens, radioactive
materials and excessive noise
Learning from the Past … Japan Bioaccumulation
• Fueling consumerism …. Doubling income
…… three basic consumer items ….. e.g DDT
zooplankton small fish large fish birds
water 0.04 ppm 0.5 ppm 2 ppm 25 ppm
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4. 8/21/2007
Story
of Bold eagle
In
from Paracelsus ....
Toxicity is Quantity related ..
USA
Anything and
Everything is toxic if
the dose is made so !!
Paracelsus
(1493-1541)
Waste takes many forms
Drinking water and death ! ..
• Woman dies
after water-
drinking
contest
SACRAMENTO, Calif. –
A woman who competed in a radio
station’s contest to see how much
water she could drink without going
to the bathroom died of water
intoxication, the coroner’s office said
Saturday.
2007 !
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5. 8/21/2007
TYPES OF POLLUTION Water Pollution
• Water Pollution
• Air Pollution
• Land Pollution
• Noise Pollution
• Thermal Pollution
• Electro Pollution
• Visual Pollution
Water Pollution – with what? Water Pollution
• Water ( about 99%) Inorganic materials - alkalis, acids, inorganic salts, ammonia,
Solids phosphates, etc.
Heavy metals - chromium, mercury, nickel, copper,
•
• Carbohydrates cadmium etc.
Proteins These are referred to as
Disinfection byproducts - trihalomethanes
Other harmful substances - organochlorides etc.
•
• Fats ‘organic material’ Physical factors - turbidity, colour, temperature etc.
• Nutrients (Nitrogen and Phosphorus)
• Microorganisms.
(On average there are about 10 million per
ml of wastewater. Many are pathogens)
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6. 8/21/2007
Industrial Sources Responsible
for Organic Pollution
Organic Pollutants
Distillery
Inorganic Pollutants
Canning
Heavy metal Pollutants organic Depletion of DO
Sugar matter
Pathogenic Pollutants
Cheese Making
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7. 8/21/2007
Industrial Sources
Responsible for Inorganic
Pollution
Dissolved Oxygen Sources Effluent Problems
Fertilizer algal blooms
reduced light
Soap and detergent penetration
ammonia and
Rubber and latex re-aeration
phosphates (eutrophication)
Agricultural farms
Eutrophication
Fertiliser Application
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8. 8/21/2007
Industrial Sources Responsible for Heavy
Metal Pollution
Sources Effluent Problems
Paper and pulp Mercury - Minamata disease
Chromium toxic to aquatic life
Tanneries Iron and self purifying
Nickel organisms
Textile Lead
Zinc Toxic to humans
Coke-oven Arsenic
Cadmium - Itai-itai disease
Metal plating Copper Bio accumulate
Silver
Sources Discharging Pathogenic
Organisms b) Air Pollution
Sources Organism Diseases
Air is considered safe when it contains no
Sewage Cholera, typhoid,
Bacteria dysentery, harmful dust and gases.
Farm slurry gastroenteritis
diarrhea, salmonellosis Polluted air affects:
Hospital waste Viruses polio, hepatitis,
Protozoa Diarrhea, dysentery, Humans
Medical laboratory (Giardia, amebiasis Animals
Cryptosporidium)
Food processing Helminths Roundworm infestation, Vegetation
pinworm,
beef tapeworm, Materials
pork tapeworm
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9. 8/21/2007
Effects from Air Pollution
Air Pollution
• Global warming has
• Ozone depletion No
(Ozone hole) Boundaries
• Acid Rain
• Various
respiratory
illnesses
Metal foundry refining in early industrial Germany, 1870s
Pollution of air
Particulate Matter PM10 (<10ìm)
- Dust (e.g. cement dust, bagasse, foundry
dust and wind blown solid dust)
- Mist
- Smoke
- Carbon black
- Aerosols
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10. 8/21/2007
Air Pollution and Health
The
Problem
of
DUST
SPM
PM 10
PM 2.5
etc.
Radioactive
nucleids
Some Polluting Process Industries TRANSPORTATION
Three modes of transport
Sulfuric Acid Plants
• Air ( airplanes etc.)
Thermal Power Stations
• Sea (ships, boats etc.)
Nitric Acid Plants • Land (automotive & locomotive)
Cement Plants Products of combustion of fuels are CO, CO2,
Foundaries NOx, hydrocarbons, particulate matter and
Plastic Industries traces of SO2, formaldehyde and Pb.
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11. 8/21/2007
c) Land Pollution
Urbanization and Concentration of Population
Municipal Solid Waste
Industrial Waste and Hazardous Waste
Uncontrolled “Land Treatment”
This is within our
Burning open dumps and forest fires university
Deforestation
Mining and Erosion
d) Noise Pollution
Exposure to prolong noise affects speech,
hearing, general health and behaviour.
Noise Levels – dB
Intensity
frequency
periods of exposure and
duration
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12. 8/21/2007
Human hearing and Frequency
Intensity (Loudness)
• Measure of acoustic
energy of the sound
vibrations
• Expressed in terms of
sound pressure
• Decibels (dB) are the
unit of measurement
on the Loudness
scale
0 16 Hz 20 kHz 5 MHz
Physical Characteristics of Sound How sound is measured
• Measurement and human perception of •Pressure, P, usually Pascals
Sound involves three basic physical P = 1/f
•Frequency, f, usually Hertz
characteristics: I = W/A
•Intensity, I, usually W/m2
– Intensity L’ = log (Q/Qo)
•Bels, L’, derived from logarithmic ratio
– Frequency •Decibels, L, derived from bels L = 10*log (Q/Qo)
– Duration
E.g. Implications of the decibel scale: doubling sound level
would mean that the sound will increase by 10*log2 = +3dB
Ten times the sound level = 10*log10 = +10dB
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13. 8/21/2007
Comparative Noise Levels (dB)
Adding decibels
Walkman (1/2 volume) 94
Telephone Dial tone 80
Talking at Three Feet 65
Quiet Urban Daytime 50
Quiet Urban Nighttime 40
Quiet Rural Nighttime 25
Industrial Noise Sources Electropollution !
• Metal fabrication (pressing, grinding, chipping etc.)
• High pressure burners in furnaces
• Turbines
- a growing
• Compressors problem
• Pumps
• Welding machines
• Cranes and other vehicles
• Pipe lines carrying high velocity fluids and solids
•Vibrating and grinding equipment
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14. 8/21/2007
Power Lines and Pollution Management
Leukemia
• “..children living in proximity to
high voltage powerlines are at
increased risk of childhood
leukaemia, but in finding effects
up to 600 metres away, they http://news.bbc.co.uk/1/hi/health/3967073.stm
Pollution can be controlled by
invoke electric field corona ion
effects as a possible causal proper choice of preventive
mechanism.
and remedial measures
Prof. Denis Henshaw, Professor of
Human Radiation Effects at the
University of Bristol
http://www.electric-fields.bris.ac.uk/
Techniques are changing … Wastewater Treatment
Cleaner
Waste water treatment
Production
Sustainable
Pollution Development
Prevention
Preventive Curative
Recycling
Pollution
Control
Complexity of Environmental Issue Volume reduction Strength reduction Physical Chemical Biological
Dispersion
1960 1980 1990
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15. 8/21/2007
Typical Wastewater
Processing
Air emissions
Wastewater Water
Primary Secondary Tertiary
Treatment Treatment Treatment
Primary sludge Secondary Sludge Tertiary Sludge
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16. 8/21/2007
Physical Methods Biological waste water treatment
Objective Aerobic treatment
Solvent extraction
Remove solid or Anaerobic treatment
•
liquid pollutants • Evaporation
based on density Distillation The organic load is defined by the Biological
Oxygen Demand (BOD).
•
difference or other Filtration
physical property In aerobic systems the water is aerated with
•
Reverse Osmosis compressed air (in some cases oxygen).
(eg. SS or floating
•
Electrodialysis
solids) Anaerobic systems run under oxygen free
•
• Adsorption conditions – biogas is a useful product.
Activated Sludge System
• Metabolism:
Bacterial decomposition and
hydrolysis
Organic Nitrogen NH3
NH3 + O2 NO2- + Energy
NO2- + O2 NO3- + Energy Nitrification
Anaerobic Zone Aerobic Zone
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17. 8/21/2007
Chemical Wastewater Treatment
Ozonation …...
• Neutralization - NaOH, Ca(OH)2, HCl, H2SO4
• Coagulation and
Flocculation - Alum, FeSO4,
• Oxidation - Sodium hypochlorite
• Disinfection - Cl2, O3, NaOCl
Dye Solutions
subjected to ozonation
Air Pollution Control
• Use tall stacks
Air Pollution and Control
• Source reduction by process and raw
material changes (eg. Improved furnace
design and low S fuel)
• Recover valuable material (eg. Hg)
• Bag filters, scrubbers, ESP, cyclone
separators
• Absorption, adsorption, combustion and
catalytic reaction
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18. 8/21/2007
Blue Skies over Puttalam 80% of the air pollution load is
contributed by the transport sector
Land Pollution Control
3R Principle
• Integrated Solid Waste Management
Good agricultural practices
• Reduce
•
• Remediation of polluted soils
Prevention of erosion and silting
• Reuse
•
Containment of hazardous waste and
waste water treatment using land
•
treatment techniques • Recycle
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19. 8/21/2007
Paper
Deaf and Blind School
Compost
Production
Abans Env Services / Paper collection
Glass ( 3 types)
Glass Factory
Plastics (all types)
Different plastic recyclers
University Colour Code – Solid Waste
Noise Pollution Control
Blue – waste paper
Orange – Plastics (milk cartons , cups)
Green – Food waste • Control noise at source by proper choice
of equipment, design modification,
mounting and proper layout
• Isolation or use of baffles
• Use of ear protection devices
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20. 8/21/2007
Desiccated Coconut Industry
DC industry
Sri Lanka
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21. 8/21/2007
Waste takes many forms
Air Emissions
Some additional slides for
information Materials,
Energy,
Water, Products,
Labour, By-Products
Capital
Solid Waste Waste Energy, Wastewater
fertilisers
sewage
(liquid domestic
Harmful Substances
and industrial waste)
Sources Substances Problems
Eutrophication
The process of
minerals minerals Disinfection byproducts trihelomethanes carcinogenic
esp. nitrates esp. phosphates
Agricultural organochlorides persistent
organic material
Pesticides (DDT) bio accumulate
eutrophication
Acids and alkalis inorganic minerals affect biological
algal bloom life, affect
toxicity of CN-, S-
competition consumers can't
for light consume fast enough Plastic, lubricant, PCB persistent, lethal
rubber, paper even at low level
dead plants dead algae
Pharmaceutical, Phenols toxic to fish,MO &
Petrochemical aquatic life
detritus
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22. 8/21/2007
Physical Effects
Physical Parameter Causative Problem
Suspended Solids china clay, peroxide, settlement, turbidity
metal salts reduce light, photosynthesis
organic solids reduce DO
Temperature Cooling water from lower DO, speed up organic
power plants matter degradation
Oil and grease Refineries, terminals Prevents O2 exchange,
storage tanks lethal to birds
Colour pigments, dyes aesthetics, toxic, reduce light
penetration
Foaming anionic detergents, aesthetics, carry SS &
surfactants pathogens, affects aeration
Occupational Health & Safety
Occupational safety and health is the discipline
concerned with protecting the safety, health and
welfare of employees of the industry and the
general public.
Safety in process design can be considered under
the following broad headings.
1. Identification and assessment of the hazard
2. Control of hazards
3. Control of the process
4. Limitation of the loss.
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