Industrial Effluents and Waste water treatment

1. Industrial Effluents and Wastewater Treatment
Naveera khan
Muhammad Ibrahim
Areesha Fareed
Shifa Tariq
L1F17BSBT0055
L1F17BSBT0058
L1F17BSBT0075
L1F17BSBT0079
Group # 7

2. Contents:
1. Effluents
2. Industrial Effluents
3. Types of Industries
 Food Industry
 Organic Chemical Industry
 Iron and Steel Industry
 Offshore Drilling
 Effects of Offshore Drilling
 Drilling fluids
 Oil spills or Leaks
 Other effects of Offshore Drilling
4. Waste water Treatment
 Primary Treatment or Mechanical Treatment
 Physical Treatment
 Screen Chamber
 Grit Chamber
 Floatation or skimming tank
 Chemical Treatment
 Sédimentation
 Coagulation
 Filtration
 Floculation
 Secondary Treatment or Biological Treatment
 Aerobic Treatment
 Activated Sludge Process
 Trickling Filter
 Anaerobic Treatment
 Oxygen Pond
 Tertiary Treatment or Advance Biological or
Chemical Treatment
 Precipitation
 Nitrogen Stripping
 Chlorination
 Other advanced methods
 Ultraviolet Light
 Ozone
• Sludge Processing
 Anaerobic Digester
 Sludge Dewatering and Drying
5. Conclusion
6. References

3. Effluents:
• Effluent is an outflowing
of water or gas to a
natural body of water,
from a structure such as a
wastewater treatment
plant, sewer pipe, or
industrial outfall.
Effluent, in engineering,
is the stream exiting a
chemical reactor.

4. Industrial Effluents

5. • It is caused by emission of industrial waste (effluent) into water bodies. It is the
main source of water pollution. Industrial waste includes organic pollutants and
toxic chemical that is heavy metals, acid and alkalis, Oils, lubricant, petroleum
and grease
Pollutants Industrial Source Impact of Industrial Waste
• Heavy Metals
1. Lead
2. Mercury
• Paint Industry
• Smelting Chemical Industry
• Lead inhibit action of bodily
enzyme
• Mercury transforms inti water
soluble methylmercury by
bacterial action and thus
contaminates fish
• Acids
1. Sulphuric Acid
• Mine Drainage • Acid cause corrosion of metal
and concrete
• Alkalies • Textile and paper industries • Alkalies in industrial waste
affects aquatic life.
• Oil • Oil refineries • Oil waste is harmful for fish and
marine birds.
• Petrochemical • Petroleum plants • Petrochemical are toxic to
marine life

6. Types of Industries:
Following are some major types
of industries responsible for
industrial effluents
1. Food industry
2. Organic chemical industry
3. Iron and steel industry
4. Offshore drilling
Paper
27%
Food
15%
Yard Trimming
14%
Plastics
13%
Metals
9%
Rubber,Leather
and Textiles
9%
Wood
6%
Glass
4%
Other
3%
TYPES OF INDUSTIES

7. 1. Food Industry:
• Vegetable washing—generate
waste water with—increased
particulate matter
• Animal processing – generate
waste water with—added
antibiotics, pesticides
2. Organic Chemical
Industry:
• These industries manufacture or use,
complex organic chemicals which
includes pesticides, paints, detergents,
plastics etc

8. 3. Iron and steel industry:
• Conservation of iron to steel,
contaminates waste water with—
hydraulic oils.
4. Offshore Drilling:
• Offshore drilling involves
exploring of oil and gas beneath
the ocean floor.

9. Effects of Offshore Drilling:
• Drilling fluid:
Drilling mud or fluid is pumped into the
well during drilling to cool, lubricate and
regulate the pressure while drilling.
Residual drilling is claimed to be toxic
and contains heavy metals and petroleum
products of various concentrations.
Impact of drilling fluid- it affects the
health and reproduction of marine animals
• Oil spills or leaks:
 It is the leakage of oil and petroleum
products into sea water due to accidents
of ships and oil takers or leakages of
pipelines or storage tanks.
 They occur when oil is produced—from
offshore well and stored temporarily or
may also happen during transportation by
pipes or tankers.

10. Other effects of Offshore Drilling:
• Damage caused by oil spills-on marine organisms such as fishes,
reptiles, amphibians and birds that live in or near the ocean are badly
effected by oil wastes which may contain volatile organic compounds.
• Oil spills deteriorate thermal insulation and damages reproductive
system.
• Gill of fish get coated with oil leading to their death.
• It interrupts the food chain, which may cause extinction of species.
• It penetrates bird’s feathers and effects its buoyancy.
• Oil spreads on water surface and thus reduces the amount of oxygen in
water. On reaching coast it harms coastal marine life.

11. Wastewater Treatment

13. • When effluent discharged into a river body such as lake, river or sea a
number of process occur like physical, chemical and biological
characteristics of water change which cause loss of organism.
• Non bio-degradable pollutant like mercury are most deadly as they
accumulate in aquatic organism which lead to Bio magnifications.
• The treatment procedure are generally divided into four steps:
I. Primary Treatment or Mechanical Treatment
II. Secondary Treatment or Biological Treatment
III. Tertiary Treatment or Advance Biological or Chemical Treatment
IV. Sludge Processing

14. I. Primary Treatment or Mechanical
Treatment:
• A mechanical way to treat effluents.
• Suspended solids and floating
materials are removed.
• Some methods of physical filtration
are:
1. Physical treatment.
A. Screen Chamber
B. Grit Chamber
C. Floatation or skimming tank
2. Chemical treatment.
A. Sédimentation
B. Coagulation
C. Filtration
D. Floculation

15. 1. Physical Treatment:
A. Screen Chamber:
Screen chamber remove dead animals, branches of tree, logs of
wood, rags and other coarse floating material.
The effluent is passed through the bar screens for rag removal. In
this section, two automatic bar screen cleaners remove large solids
(rags, plastics, etc.) from the raw sewage. The collected material is
placed in dumpsters to be taken later to the landfill.
B. Grit Chamber:
Grit include sand, ash, egg shell etc. Of diameter less than 0.2 mm. Next, the
effluent moves to the grit tanks. These tanks reduce the velocity of the effluent so
that heavy particles may fall to the bottom. The solids are pumped to an auger pump
which separates the water from the grit while the water moves onward. The grit
(mostly inorganic solids) goes to a dumpster which is taken to a landfill. There are
two complete grit removal systems which are rotated in operation for equal hours.
C. Skimming Tank:
Fats, waxes, fatty acid, soap, minerals and vegetable oil present in waste water are
collectively called as oil and grease. As oil and grease are lighter than water they are
normally separated by natural flotation. The bubbles of air are passed on the bottom of the
tank and floating matter rises and remain on the surface of waste water which can be
separated easily.

16. 2. Chemical Treatment:
A. Sedimentation:
Settling down of suspended particles at the bottom of water is called
Sedimentation.. In this process water is collected into big pond, slowly-
slowly impurities are settled down by gravitation. The main objective of
Sedimentation are:
• The suspended and colloidal impurities are separated in sedimentation
tank by gravitation.
• The main principle of sedimentation is to allow water to rest or flow at
a very slow velocity.
• The process of settling of particles depend mainly on velocity of flow,
size, shape and specific gravity of particles and viscosity of liquid.
B. Coagulation:
• Colloidal particles which are fine particles of size finer than 0.0001
mm carry electric charges on them.
• The turbidity in water is mainly due to the presence of very fine
particles of clay, silt and organic matter.
• Coagulation is the process in which certain chemical agent is mixed
with water then colloidal and suspended particles are agglomerated and
form insoluble metal hydroxide known as flocks.
C. Filtration:
• Filtration is done in order to remove colloidal and suspended matter
remaining after sedimentation and to remove bacterial load.
• The process of filtration usually consist of allowing the water pass
through thick layer of sand or porous material which retain coarse
impurities on its surface and in pores.
D. Flocculates:
• Flocculates are organic high molecular weight compound comprising
many inorganic group. - These group groups undergo ionization when
dissolve in water.
• Two important flocculates are
1. polyacrylamide
2. BA-2 flocculate.
• Most of colloidal particles carry negative surface charge but molecule of
flocculate are positively Hence neutralization of charges take place.

17. II. Secondary Treatment:
• It is the process in which microorganism play a very important role for the
treatment of effluent.
• Microorganism like bacteria, fungi decompose the organic waste and
convert into simpler form.
• There are two types of secondary treatment:
1. Aerobic Treatment - The treatment which is carried out by microorganism in the
presence of oxygen.
A. Activated Sludge Process
B. Trickling Filter
2. Anaerobic Treatment - The treatment which is carried out by aerobes in the
absence of oxygen. The need of oxygen is supplied by oxidation of oxygenated
compound for e.g. SO2
3. Oxygen Pond

18. Aerobic Treatment:
A. Activated Sludge Process:
• Sewage from sedimentation tank enter into aeration tank. Here 20 – 30 % of active sludge is mixed. The mixture is aerated and
mixed in the tank for about 4 to 8 hours.
• An efficient aeration for 3 – 6 hour is occupied for sludge while for industrial waste 6 – 24 hour of aeration is required.
• The microorganism oxidize organic matter, in the presence of abundant quantity of oxygen in the aeration tank. Sewage is
allowed to settle in secondary sedimentation tank.
• This settled sewage has undergo aeration and has active microorganism.
• The activated sludge is obtained by settling sewage in the presence of
excess oxygen. Thus activated sludge is that sludge which settle down
after the sewage has been freely aerated and agitated for a certain time.
• When activated sludge is mixed with effluent, the aerobic bacteria
oxidize the organic matter and promote coagulation and flocculation.
• Some advantages of activated sludge method are:
i. The effluent is free from bed smell and odor
ii. Give Clear sparkling treated liquid

19. B. Trickling Filter:
• After primary treatment the
effluent is passed through the bed
the filter medium which is
consisting of bed of stone in
which microorganism or bacteria
are present. - Bacteria get
nutrient. Bacteria attack on
carbohydrate, protein, oil, fats
which is essential for the growth
of bacteria.

20. Oxidation Pond (Lagoon)
• The oxygen pond is shallow pond where waste water is purified by action
of algae and aerobic bacteria.
• Latter on oxygen is released during the process of photosynthesis. Aerobic
bacteria get O2 from atmosphere and convert the organic matter present in
sewage and liberate CO2 which is again taken by algae during the process
of photosynthesis.
• The contents of the aeration tanks are commonly referred to as the mixed
liquor suspended solids (MLSS).
• The activated sludge converts organic substances into oxidized products
and a settle able flock which is settled out in the secondary clarifiers.

21. III. Tertiary Treatment or Advance waste
water treatment:
• The main function of tertiary treatment is to decrease the load of
nitrogen and phosphorous compound present in the effluent by the
following process:
1. Precipitation
2. Nitrogen Stripping
3. Chlorination

22. A. Precipitation:
The effluent received after the secondary
treatment is mixed with calcium oxide. The
lime then react with phosphorous compound
in waste to from insoluble calcium
phosphate, which then settle down at the
bottom of settling tank.
B. Nitrogen Stripping:
Nitrogen present in waste water is generally in
the form of ammonia gas, nitrates and nitrites.
Ammonia is highly undesirable in streams and
lakes because it is extremely lethal to aquatic
biota. Nitrogen eventually enhance
Eutrophication In order to remove nitrogen air is
forced through the effluent which thereby result
in the removal of ammonia gas.
C) Chlorination:
It is the process in which chlorine is used to kill micro-
organism.
The main purpose of chlorination are
• To assist in the formation of floc in the process of
coagulation together with other chemical. - To prevent
corrosion of sewers.
• To prevent spread of epidemic.

23. Other advanced methods
• Some other advanced methods of tertiary treatment are:
A. Ultraviolet Light
B. Ozone

24. A. Ultraviolet Light:
• The water is passed through banks of
cylindrical, quartz-jacketed fluorescent
bulbs. Some dissolved materials, such
as iron and some organic compounds,
can also absorb some of the light.
• Ultraviolet disinfection is becoming
more popular because of the increasing
complications associated with the use
of chlorine.

25. B. Ozone:
• Ozone is too unstable to store, and has to be made as it is used. It is
produced by passing an electrical discharge through air, which is then
bubbled through the water.
• While chlorine can be dosed at a high enough concentration so that
some of it remains in the water for a considerable time, ozone is
consumed very rapidly and leaves no residual.
• It may also produce some chemical byproducts, but probably not as
harmful as those produced by chlorine.

26. IV. Sludge Processing:
• Sewage processing describes the processes used to manage and
dispose of sewage sludge produced during sewage treatment.
• It has two methods:
1. Anaerobic Digester.
2. Sludge Dewatering and Drying.

27. 1. Anaerobic Digester
• In the anaerobic digesters another group of
bacteria begin to digest and dissolve the
solids to their basic components.
• This process uses bacteria which do not
need atmospheric oxygen to survive, so
therefore, no air is bubbled into the tanks.
• The anaerobic digesters produce a stable
sludge which is readily dewatered.

28. 2. Sludge Dewatering and Drying
• The engine generator runs on digester or natural gas. The generator
supplies electrical power to essential pieces of treatment plant
equipment.
• After most of the organic solids have been digested, the sludge is
pumped to sand drying beds or to the belt filter presses.
• The dewatered solids are then squeezed between two belts to further
dewater them.
• The resulting solids are in the range of 18-20 percent solids.

29. Conclusion:
• The issue of industrial effluents concerns every nation on the planet.
• As a result, many steps have been taken to seek permanent solutions to
the problem..
• Better technology is being developed for disposal of waste and
recycling as much polluted water in the industries as possible.
• Wastewater treatment is an important initiative which has to be taken
more seriously for the betterment of the society and our future.

30. References:
• M. Samer. (2015). Biological and Chemical Wastewater Treatment
Processes. Retrieved from: https://www.intechopen.com/books/wastewater-
treatment-engineering/biological-and-chemical-wastewater-treatment-
processes
• Patterson, J W. (1985). Industrial wastewater treatment technology.
Retrieved from: https://www.osti.gov/biblio/7253209
• Kumar. (2013). Waste water treatment. Retrieved from:
https://www.slideshare.net/kumar_vic/waste-water-treatment-18653689
• Nusrat Bashir. (2016). Wastewater Treatment. Retrieved from:
https://www.slideshare.net/NusratBashir3/waste-water-treatment-ppt
• Sarita Dhal. (2015). Industrieal Waste. Retrieved from:
https://www.slideshare.net/saritadhal37/industrial-waste-48273167