1. Under the guidance of: Dr. M.K. Sateesh
WASTE TREATMENT
Presented by:
Sadhana Reddy
Under the guidance of:
Dr. M.K. Sateesh

2. CONTENT OVER VIEW OF WASTE WATER TREATMENT INTRODUCTION
SOURCES FOR WASTE WATER
TERMS
COMPOSITION OF DOMESTIC WASTE WATER
OVER VIEW OF WASTE WATER TREATMENT
Primary Treatment
Secondary Treatment:-Activated sludge , Trickling filter & oxidation pond.
Tertiary:-Removal of Nutrients , Heavy metals , Pathogens

3. INTRODUCTION
The term sewage treatment is now a days is replaced by waste water treatment.
Sewage treatment is the process of removal of contaminants from waste water.
The treatment is of chemical, physical and biological process
Their are 2 types of waste water based on the out lets-:
1.House and Hotel out let.
2.Industrial out let

4. SOURCES FOR WASTE WATER

5. Contamination of concern in water treatment
Suspended solids
Bio degradable organics
Pathogens and parasites
Nutrients
Priority pollutants
Refractory organics
Heavy metals
Dissolved inorganics

6. TERMS Biochemical Oxygen Demand[BOD]:-
It is the amount of dissolved oxygen [DO] consumed by microorganisms for the biochemical oxidation of organic.
Chemical Oxygen Demand [COD]:-
It is the amount of oxygen necessary to oxidize the organic carbon completely to CO2’ H2O, and ammonia.

7. TYPES OF BOD (i) Carbonaceous BOD (CBOD)
CBOD is the amount of Oxygen used by a mixed population of heterotrophic microorganisms to oxidize organic compounds
Org comp O2 hetrotrophs CO2+H2O+NH4+ Bacterial mass
Bacterial bio film O2 𝑝𝑟𝑜𝑡𝑜𝑧𝑜𝑎 Protozoa biomass +CO2
(ii) Nitrogenous Oxygen demand (NOD)
Autotrophic bacteria such as nitrifying bacteria also require oxygen to oxidize NH4+ to nitrate. The oxygen demand exerted by nitrifiers is called as NOD and also autotrophic BOD

8. COD Chemical oxygen demand (COD)
COD is the amount of oxygen necessary to oxidize the organic carbon completely to CO2 , water and ammonia.
COD is measured via oxidation with potassium dichrome (K2CR2O7) in presence of sulphuric acid & silver is expressed in mg/L.
If COD is higher than BOD it means that the amount of organic compounds are high which are not easily bio degraded.
In untreated domestic waste, water COD ranges between to 1000mg/L

9. Composition of domestic waste
Domestic waste water is a combination of human and animal excreta (faeces & urine) and grey water resulting from washing, bathing and cooking.
People excrete g wet weight of faeces & 1& 1.3 L of urine per capita per day.
Domestic waste is composed of mainly
Proteins %
Carbohydrates %
Fats & oils 10%
Urea derived from urine

10. Contd…
Even it includes a large number of trace organic compounds that is pesticides , surfactants, phenol & priority pollutants
The latter category comprises non metals (As , SC) metals (Cd, Hg, Pb) benzene compounds ( benzene , ethyl benzene) & chlorinated compounds

11. Overview of waste water treatment
Physical forces as well as chemical & biological process drive the treatment of waste water.
Unit operations :- Treatment methods that rely on physical forces are called unit operations. These includes
Screening
Sedimentation
Filtration or flotation
Unit process:- treatment methods that rely on chemical and biological processes are called unit process

12. Contd… Chemical unit consists of Biological unit process involves
1. Include disinfection
2. adsorption or precipitation
Biological unit process involves
1. microbial activity
2. organic matter degradation
3. removal of nutrients

13. Contd.. Waste water treatment comprises of four steps
Preliminary treatment :- the objective of this operation is to remove debris and coarse materials that may clog equipment's implant.
Primary treatment :- treatment is brought about by physical process such as screening and sedimentation.

14. Contd..
3. Secondary treatment:- Biological and chemical are used to treat waste water. Even nutrient removal also generally occurs during secondary treatment.
Biological :- activated sludge, trickling filter, oxidation ponds
Chemical :- Disinfection
4. Tertiary or advanced treatment:- unit operations and chemical unit process are used to further remove BOD, nutrients, pathogens, parasites and sometimes toxic substances

18. Activated sludge process
Activated sludge is suspended growth process that began in England at the turn of the century.
This process has since been adopted world wide as a secondary biological treatment for domestic waste water.
This process consists essentially of an aerobic treatment that oxidises organic matter to CO2, H2O , NH4 & new cell biomass
Air is supplied to this process by diffused or mechanical disposed

19. Contd…
Effluent from primary treatment is pumped into a tank and mixed with bacteria – rich slurry known as activated sludge
Air or oxygen is supplied to encourage the growth of bacteria.
The material then goes to a secondary setting tank where the water is siphoned off the top of the tank & sludge is removed from the bottom.

20. Contd..
Food to Microorganism ratio [F/M] :- A portion of the sludge in the clarifier is recycled back to aeration basin & the remainder is wasted to maintain a proper F/M
F/M ratio indicates the organic load into the activated sludge system & expressed in kilogram BOD per kilogram of MLSS per day.
F M = Q∗BOD MLSS∗V
Q = flow rate no of sewage in million gallons per day
MLSS= Mixed liquor suspended solids (mg/L)
V= Volume of aeration tank (gallons)

21. Activated sludge

22. Major contents of sludge
Bacteria
Fungi
Zooglea
Pseudomonas
Flavobacterium
Alcaligenes
Achromobacter
Corynobacterium
Acinebacter
Bacillus
Filamentous
Eg: Sphaerotilus
Gliding Bacteria
Eg:- Beggitoa
Geotrichum
Pencillium
Cephalosporium
Cladosporium
Alternaria

24. Trickling filter
It is the processing unit which will be circular either rectangular tank containing the filter medium.
Depth will be approximately 1.0 to 2.5m this surface area is provided for microbial growth.
The filter media used in trickling filters are stone[crushed limestone & granite], ceramic material, treated wood, hard coal or plastic media.

26. Microorganisms found in trickling
BACTERIA
FUNGI
ALGAE
PROTOZOA
Zooglea
Fusarium
Ulothrix
Bodo
Pseudomonas
Penicillium
Phormidium
Monas
flavobacterium
Aspergillus
Anacystis
Colpidium
Ahromobacterc
Mucor
Euglena
Vorticella
Alcaligenes
Geotrichum
Chlorella
Amoeba
FB:Sphaerotilus.
Yeasts
Arcella
N. communis, N. oligotropha
Nitrobacter

27. Oxidation pond
Here oxygenation is usually achieved by diffusion and by photosynthetic activity of algae
In the ditches the microorganisms grow as suspended particles.
The water in pond moves in clock wise direction.
Temperature is for about 22 C
Duration time is 15 hours
Area is of 15 million gallons

29. Removal of nitrogen
Biological oxidation of nitrogen from ammonia to nitrate[NITRIFICATION]followed by DENITRIFICATION the reduction of nitrate to nitrogen gas.
Nitrosomonas (ammonia oxydizing bacterium or AOB) & Nitrospira ( anitire oxidizing bacteria or NOB)
The target region of Nitrosomonas is Amo Agene & 16Sr DNA is target region of Nitrospira
BABE:- Bio augmentation batch enhanced process can be used to augment nitrification in activated sludge operating at sub optional solid retention times

30. Different systems Single sludge system
This system comprise a series of aerobic & anaerobic tanks in lieu of single aeration tank .

31. Multi sludge System
Carbonaceous oxidation, nitrification & de nitrification are carried out in three separate systems
Methanol or settled sewage can serve as source of carbon for de nitrifier

32. Bardenpho Process
The process consists of 2 aerobic & 2 anoxic tanks followed by sludge setting tank

33. Removal of phosphorus A/O ( Anaerobic/ oxic ) process
A/O process consists of anaerobic zone. During anaerobic phase , inorganic phosphorus is released from the cells as a result of polyphosphate hydrolysis. The energy released is used for up taking of BOD
Bardenpho process: This system remove nitrogen as well as phosphorus.
University of cape town process (UCT):In this system train of 3 tanks of anaerobic-anoxic-aerobic followed by clarifier.

34. UCT

35. BY MICROORGANISMS
Polyphosphate accumulating organism [PAOs] are selectively enriched and accumulated large quantities of phosphorous with in the cell.
Up to 20% of their cell.
Example for PAOs is Gammaproteo bacteria of genus Acinetobacter ,Microlunatus phospovorus.
Polyphosphate hydrolysis organism[PHA]are hydrolysed P.
Example: Betaproteo bacteria, Lampropedia spp.

36. PAO”s Organism

37. Heavy metal Removal
Heavy metals are the major toxicants found in industrial waste waters.
The affinity of biological solids for heavy metals was found to follow the order:Pb>Cd>Hg>Cr3+>Cr6+>Zn>Ni.
It was reported that biofilm microorganisms were 2 to 600 times resistant to metals than planktonic.

39. Disinfection Chlorine Temperature. Effect of pH.
It help in inactivation of microorganisms by cell injury.
Disruption of cell permeability.
Expose to chlorine leads to leakage of proteins,RNA and DNA.
Interrupts nutrient transportation, inhibits cell respiration, damages iron sulfur center.
Arest enzyme action by accumulation of hydrogen peroxide.

40. Disadvantages
Chlorination of drinking water is risk for bladder, kidney and colorectal cancers.
The disinfection by products [DBPs] are mutagens or carcinogens and teratogens.
Cardiovascular diseases.
Examples of microorganisms- E. coil, Poliovirus,
Campylobacter jejuni.

41. Chloramination Examples:-
NH3 + HOCl NH2Cl + H2O (Monochloramine, pH 8.5)
NH2Cl + HOCl NHCl2 + H2O (Dichloroamine, pH 4.5)
NHCl2 + HOCl NCl3 + H2O (Trichloroamine, pH <4.5)
Examples:-
Bacteria- E.coil, Coli forms, Mycobacterium fortuitism, M.avium, M. Intracellular , S. tphimurium, Shigella sonnei.
Viruses- Polio I, Hepatitis A , Coli phage MS2, Rotavirus SA11.
Protozoan : Cysts-Giardia muris

42. Chlorine dioxide
Destruction of cysts pathogenic protozoa such as Naegleria gruberi.
At pH 9.0 bacteriophage F2 is inactivated by acting up on protein coat
It disturb the protein synthesis in bacterial cell.
Examples-Bacillus subtilis spores, K. pneumonia.

43. Chlorine dioxide

44. OZONE
By passing dried air between electrodes separated by air gap and applying alternating current.
The volts used here is from 8000 to 20,000V.
Standard oxidation potential is 2.07eV but for in activation of bacteria it needs 0.10g/L.
Example-E. coli to 0.2
Enteric viruses-0.04 to 0.42.
Mycobacterium > Polio virus 1 > Candida parapsilosis > E.coi >
Salmonella typhimurium.

46. Process DISADVANTAGES
Free radicals are produced to aqueous media that inactivates microorganisms.
DISADVANTAGES
Mutagenic by product is bromate (BrO3 ) carcinogen
More electricity, costly
It don’t cause damage to bacterial spore DNA

47. U.V LIGHT @ wavelength of 253.7nm It damages micro organisms DNA
It causes thymine & cytosine dimer which block DNA replication
For viruses it damages viral genome, or virus coat
Protozoan cysts >bacterial spores>viruses> vegetative bacteria.

48. DISADVANTAGES Difficulty in determining U.V dose
Formation of biofilms on lamp surface
Electrical problem

49. PHOTO INACTIVATION Solar radiation PhoTODYNAMIC inactivation
Solar ≥ 600w/m2 for 5 hours to reduce pathogens
Ex:- vibrio cholerae, salomenella.
Water in plastic bottle is exposed to sunshine for 7 h to 550C
It is also called as photochemical disinfection
It consists of visible or sunlight as energy source, O2 & sensitizer dye such as methyl blue, rose Bengal or eosin
It reduce the poliovirus I for 1.8 log
Here flow will be 50m3/h
35min in reduce 4-5 log of microorganisms

50. PHOTODYNAMIC INACTIVATER

51. PHOTO CATALYTIC
Titanium dioxide [Tio2]+Fluorescent or sunlight=photo catalytic.
Even it degrades the endotoxin which are released from the cells.

53. REFERENCES http:⁄⁄ www.scitrav.com ⁄ wwater53⁄ water lnk.htm
[collection of web pages on activated sludge]
⁄enviro ⁄ html⁄icr⁄dbp.htm1
[disinfection byproducts from U.S.EPA]
http :⁄⁄ ⁄owm⁄ mtb⁄ U.V.pdf
[U.V disinfection]
Waste water Microbiology[3rd edition] by GABRIEL BITTON.
Environmental Biology for Engineers and Scientists by David A.Vaccari, Peeter F. Strom,Jaes E.Alleman

54. THANK YOU