Some advanced topics in wastewater treatment and process

1. Advance Methods in Waste
Water Management
Submitted by,
Sujindran. B
Vicknesh. K

2. Water circulates through the land just as it does through
the human body, transporting, dissolving, replenishing
nutrients and organic matter.
Survival
Cooking
Bathing
Washing

3. Necessity for Water
Treatment• To provide desired quality of water
• To provide and maintain hygienically safe
water
• Removal of hardness, dissolved gases,
odours etc..,
• Eliminating tuberculative and corrosive
nature of water

4. Purification process in public
water supplies
• Screening
• Sedimentation
• Filtration
• Disinfection
• Aeration
• Softening
• Miscellaneous treatments

5. Unit Operation
Changes formed are
»Physical
»Chemica
l
»Biologic
al
Important Unit Operations
•Gas Transfer
•Ion Transfer
•Solute Stabilization
•Solid Transfer
•Miscellaneous
Operations
•Solid Concentration and
Stabilization

6. Chemical Coagulation
Chemicals Used
Aluminum sulphate (alum)
 Polyaluminium chloride (Liquid
alum)
Alum potash
Iron salts (Ferric sulphate or
Ferric chloride)Particles that cause turbidity (e.g. silt, clay) are generally
negatively charged, making it difficult for them to clump
together because of electrostatic repulsion. But coagulant
particles are positively charged, and they chemically attracted
to the negative turbidity particles. With mixing the neutralized
particles then accumulate to form larger particles which settle

7. Super Chlorination
• Super chlorination is a process in which the
chlorine level in water is raised to abnormally
high levels over a very short period of time.
• Over time and with extended use, organic
wastes build up in pool water. These include
body oils/sweat, other body fluids and suntan
lotions.
• Generally, one gallon of liquid chlorine is
needed for every 10,000 gallons of pool
water.
• Super chlorination is used in heavily polluted
water, as well as in the orthotolidine test and

8. Centrifugation
Centrifugation is a separation process
which uses the action of centrifugal force
to promote accelerated settling of particles
in a solid-liquid mixture. Phases formed in
the vessel during centrifugation are,
• The Sediment - The flocs
• The Centrate - The supernatant water

9. 1. Cylindroconical bowl
2. Helical extraction screw (scr
3. Feed
4. Distributor
5. Ring space
6. Settled product
7. Liquid level
8. Drying zone
9. Clarified liquid
10. Adjustable thresholds
Centrifugation

10. Incineration
• Incineration of waste materials converts the
waste into ash, flue gas and heat
• The ash is mostly formed by
the inorganic constituents of the waste, and may
form particulates carried by the flue gas.
• The flue gases must be cleaned of gaseous and
particulate pollutants before they are dispersed
into the atmosphere.
• In some cases, the heat generated by
incineration can be used to generate electric
power

11. The Spittelau
incineration plant
in Vienna, Austria,
designed
by Friedensreich
Hundertwasser.

12. Thermal Desalination
The thermal
desalination process uses
energy to evaporate water
and subsequently
condense it again. When
there is waste heat or
sufficient electricity
available, as is often the
case with refineries and
power plants, thermal
desalination is an efficient

13. Recarbonation
• A process in which carbon dioxide is
bubbled into the water being treated to
lower the pH. The pH may also be lowered
by the addition of acid. Recarbonation is
the final stage in the lime–soda ash
softening process. This process converts
carbonate ions to bicarbonate ions and
stabilizes the solution against the
precipitation of carbonate compounds

14. Process