ENVIRONMENTAL POLLUTION.ppt _Compatibility Mode_

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					                                                                            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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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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       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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                             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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                                                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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                                                                 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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     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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                                                           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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       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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     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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                                                          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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    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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             Typical Wastewater
                 Processing
                                Air emissions

Wastewater                                             Water
        Primary        Secondary            Tertiary
       Treatment       Treatment           Treatment



     Primary sludge   Secondary Sludge   Tertiary Sludge




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            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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      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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     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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                                                     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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Desiccated Coconut Industry
        DC industry
          Sri Lanka




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                                                                                                            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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                   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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