A simple presentation on water purification using microorganisms here the water purification process activated sludge is discussed and trickling filters usage and what is use of water purification and use of microorganisms

1. JAYAKUMAR G

2. What is water Purification??
 Water purification is the collective name for a group
of processes that make water more suitable for
drinking, medical use, industrial use, and so on
 water purification is the process by which undesired
chemical compounds,organic and inorganic materials
and biological contaminants are removed from water.

3. What is the need of pure water???
 About 844 million people lack even a basic drinking-
water service. In fact, approximately 159 million
individuals are dependent on surface water, the World
Health Organization (WHO) reports.
 Additionally, at least 2 billion people utilize a drinking
water source that is contaminated with feces. These
water sources can transmit water-borne diseases,
which have been linked to about 502,000 diarrheal
deaths every year.

5. WHO response
 WHO works with Member States and other partners
to:
 promote national policies and investments that
support case management of diarrhoea and its
complications as well as increasing access to safe
drinking-water and sanitation in developing countries;
 build capacity in implementing preventive
interventions, including sanitation, source water
improvements, and household water treatment and
safe storage

6. Methods to purify water
 BOILIING
 FILTERING
 DISTILLING
 CHLORINATION
 Water is purified with filters to remove larger
protozoans, and by chemical or UV disinfection to kill
bacteria and other small pathogens.

7. Water filtering is a method used to filter out undesired chemical
compounds, organic and inorganic materials, and biological contaminants
from water. The purpose of water filtration is to provide clean
drinking water.
Water chlorination is the process of
adding chlorine or chlorine compounds such as sodium hypochlorite
to water. This method is used to kill bacteria, viruses and other microbes
in water. In particular, chlorination is used to prevent the spread of
waterborne diseases such as cholera, dysentery, and typhoid
Boiling is the process by which a liquid turns into a vapor when it is heated
to its boiling point. The change from a liquid phase to a gaseous phase occurs
when the vapor pressure of the liquid is equal to the atmospheric pressure
exerted on the liquid
Distillation is the process of separating components of a mixture based on
different boiling points. Examples of uses of distillation include purification
of alcohol, desalination, crude oil refining, and making liquefied gases from
air.

8. Water purification steps
 Water is first passed through a system of filters and a
coagulating agent is added to remove particulate matter.
 Water is then passed through a membrane filter to remove
large pathogens such as cryptosporidum and giardia.
 To finalize the purification process, chemical disinfection
(usually with chlorine or ozone ) or UV light is applied to
the water to kill bacteria, viruses, and the hardy cysts
produced by cryptosporidium and giardia.

9. Drinking Water Purification
 In order to purify drinking water from a source (such
as a lake, river, reservoir or groundwater), the water
must go through several steps to remove large particles
and different types of pathogens.
 1. Pumping and Containment: Water is pumped from
the source into holding tanks.
 2.Screening: Water is passed through a screen filter to
remove large debris.

10. 3.Storage: Water is stored in reservoirs, tanks, and
water towers in preparation for purification.
Sometimes water is “pre-cholrinated” in this
system to prevent bacterial growth while it is in
storage.
4. Coagulation and Sedimentation: Although there
are many processes by which large particles are
removed from drinking water, most water
purification systems implement some kind of
coagulation system. A chemical that causes
particle aggregation is added to the water, and
clumps of particles form and settle to the bottom
of the reservoir. This is called sedimentation.

11. 5.Membrane Filtration: Membrane filters are
able to remove all particles larger than 0.2 um.
Larger pathogens such as giardia lamblia and
cryptosporidium are trapped in these filters,
but the cysts they produce are small enough to
pass through.
6.Disinfection: Before water is considered
potable, it must be disinfected to remove any
pathogens that passed through the membrane
filter.

12. Methods of Disinfection
 Chlorination is the most common form of
disinfection.
 Chlorine is a strong oxidant, and rapidly kills many
microorganisms, especially bacteria. Because
chlorine is a toxic gas, it can also be dangerous to
sanitation workers.
 Chlorine based compounds like choloramine are
often used. Although chlorine is very effective
against bacteria, it is not as effective against the
cysts formed by protozoans (like giardia lamblia
and cryptosporidium). Chlorine can sometimes
leave residual byproducts in water.

13. Ozone is an unstable molecule that readily gives
up one atom of oxygen providing a powerful
oxidizing agent. This agent is toxic to most
waterborne organisms. Ozone is widely used in
Europe, and is an effective method to kill cysts
formed by protozoans. It also works well against
almost all other pathogens.
Ultraviolet Light is very effective at inactivating
protozoan cysts, and will also kill bacteria and
viruses. However, it is not as effective in cloudy
water. It is sometimes used in concert with
chlorination.

14. Waste water treatment
 Waste water treatment comprises of three different
procedures
 1.Primary treatment
 2.secondary treatment(Biological treatment)
 3.Tertiary tretment

16. Primary Treatment
In primary treatment, sewage is stored in a basin where solids
(sludge) can settle to the bottom and oil and lighter substances can
rise to the top. These layers are then removed and then the
remaining liquid can be sent to secondary treatment. Sewage sludge
is treated in a separate process called sludge digestion.
Secondary Treatment
Secondary treatment removes dissolved and suspended biological
matter, often using microorganisms in a controlled environment.
Most secondary treatment systems use aerobic bacteria, which
consume the organic components of the sewage (sugar, fat, and so
on). Some systems use fixed film systems, where the bacteria grow
on filters, and the water passes through them. Suspended growth
systems use “activated” sludge, where decomposing bacteria are
mixed directly into the sewage. Because oxygen is critical to
bacterial growth, the sewage is often mixed with air to facilitate
decomposition.

18. Activated sludge
 The activated sludge process is a type of wastewater
treatment process for treating sewage or industrial
wastewaters using aeration and a
biological floc composed of bacteria and protozoa.
 oxidizing carbonaceous biological matter, oxidizing
nitrogenous matter:
mainly ammonium and nitrogen in biological matter,
removing nutrients(nitrogen and phosphorus)

19. Aeration tank where air (or oxygen) is
injected in the mixed liquor.
Settling tank (usually referred to as "final
clarifier" or "secondary settling tank") to
allow the biological flocs (the sludge
blanket) to settle, thus separating the
biological sludge from the clear treated
water

26. Trickling filters
 A trickling filter is a type of wastewater
treatment system. It consists of a fixed bed
of rocks, coke, gravel, slag, polyurethane foam,
sphagnum peat moss, ceramic, or plastic media over
which sewage or other wastewater flows downward
and causes a layer of microbial slime (biofilm) to grow,
covering the bed of media. Aerobic conditions are
maintained by splashing, diffusion, and either
by forced-air flowing through the bed or natural
convection of air if the filter medium is porous.

28. Tertitary treatment
 Tertiary treatment is the final cleaning process that
improves wastewater quality before it is reused,
recycled or discharged to the environment.
The treatment removes remaining inorganic
compounds, and substances, such as the nitrogen and
phosphorus.
 Wastewater may still have high levels of nutrients such
as nitrogen and phosphorus
 These can disrupt the nutrient balance of aquatic
ecosystems and cause algae blooms and excessive weed
growth

29. Conclusion:
 Microrgnisms play a crucial role in waste water
treatment
 Microorganisms recycle nutrients in the
environment, by decomposing organic materials
 microbes use nutrients and chemical substances
found in the environment for their own survival.

30.  THANK YOU