1.
SEWAGE DISPOSAL,
BIOREMEDIATION
Delrose Thomson
MSc Botany

2.
SEWAGE
• waste matter such as water or human
urine or solid waste:
• Some cities in the world do not have
proper facilities for the disposal of sewage.
Raw/untreated sewage is being pumped
into the sea, from where it pollutes our
beaches.

3.
SEWAGE DISPOSAL
• The process of removing and destroying or
converting the noxious substances of
sewage especially by ammonification and
nitrification through bacterial action.
• Sewage disposal system means sanitary
drainage systems, septic
tanks,cesspools,imhoff tanks, leaching pits,
surface and subsurface leaching filter beds,
and trickling filters,sand bed, or other
approved facilities for the disposal of sewage by
means other than through a public sewer.

4.
PREVENTION OF SEWAGE OVER FLOW
CONSERVE WATER
• Conserving water can help reduce
pollution of our waterbodies.
• More water used in our homes means
more water treated at wastewater
treatment facilities.

5.
• Shut off faucets when not in use
• Repair leaking faucets or pipes
• Take shorter showers
• Install low flow devices on faucets and showerheads and
install low flow/dual flush toilets
• Replace older dishwashers and washing machines with
newer, more energy efficient and water conserving models
• Use rainwater to water your gardens by installing rain barrels

6.
Don't Dump Fats, Oil and Grease
Down Drains
• The build-up of fats, oils and grease causes
many collection system overflows.
• Grease, oils or fatty substances dumped
down residential or restaurant kitchen sinks
can build-up in sewer pipes.
• These build-ups can cause Overflows or
back-ups of sewage into homes.
• Instead of dumping them down the sink, allow
fats, oils and grease to cool and dispose of
them in the trash.

7.
• Certain materials that are commonly flushed
down the toilet or dumped into kitchen sinks
can damage sewer systems and wastewater
treatment equipment,
• Diapers
• Baby Wipes
• Personal Hygiene Products
• Do not flush any of these items, no matter
how small, down the toilet. Throw them in the
trash

8.
Sewage disposal systems
• Sanitary pit privies
• Cesspools
• Septic tanks
• Imhoff tanks.
• Contact beds
• Trickling filters
• Sand beds

9.
Sanitary pit privies
• The sanitary pit privy may be an effective method
for the disposal of human body waste
• properly located, constructed and maintained.
• While few residential homes in towns and cities
use this method of sewage disposal, many
cottages and parks still find use for the
“outhouse”.
• Because the improper disposal of human wastes
is a serious health problem

10.
• Pit privies should not be placed in densely
populated areas, boggy or marshy areas, or
areas where soil is minimal and bedrock is
largely exposed. Soil depth and type should be
such that:
• the pit is at least 1 m x 1 m (3 ft x 3 ft) square
and 1.5 m (5 ft) deep
• the bottom of the pit must be 1 m (3 ft) above
the groundwater table, bedrock

11.
• When sanitary privies fill upto with in a few feet of
soil surface ,the waste should be properly covered
with dirt .

12.
cesspools
• Disposal of sewage on a small scale,such as
from a private home.
• Hole in the ground with walls conctructed of
stone or bricks
• Solids drop to the bottom of cess pool
undergo decomposition.

13.
Septic tank
• A septic tank is an underwater sedimentation tank used for
waste water treatment through the process of biological
decomposition and drainage.
• A septic tank makes use of natural processes & proven
technology to treat wastewater from household plumbing
produced by bathrooms, kitchen drains,and laundry.
• A septic tank system has a relatively simple design. It is an
underground watertight container (mostly rectangular or
round) made of fibre glass, plastic or concrete.
• The Compartments in a septic tank and normally a T-shaped
outlet prevent the sludge and scum from leaving the tank and
travelling into the drain field area.

14.
Imhoff tanks
• Imhoff tanks are mainly for medium
population and sewage with separate
solid and liquid portions while septic
tanks are for a smaller population with
mixed sewage wastes. Imhoff tank is a V-
shaped anaerobic treatment chamber for
wastes.

15.
Trickling filters
• Trickling filter process is one of the types
of aerobic wastewater treatment.
• It is a fixed-bed bioreactor that is the part of
secondary wastewater treatment, which
eliminates the coarse particles, suspended
organic and inorganic waste, small colloids
etc. out of the primary effluent.
• A trickling filter is also called biological
filter, as it makes the use of active microbial
mass as a bioweapon to degrade the waste
out of primary sewage.

16.
• Use of microbes for cleaning up contaminated or
polluted environment.
• Process by which the atmospheric concentrtion
of toxic waste is brought down to below
permissible limits,using living organisms or their
enzymes under controlled condition.
• Clean up polluted environment.
• To repair damaged natural system.
• Solve environmental problem employing
biological agents.

17.
Microorganisms
• Aerobic bacteria
• Pseudomonas,Alcaligens,Sphingomonas,Rodococ
cus and Myconacterium.
• Degrade pesticides hydrocarbons:alkanes and
polyaromatic compounds.
• Methanotrophs
• Aerobic bacteria that utilize methane for carbon
and energy.
• Active against a wide range of compounds.

18.
• Anaerobic bacteria
• Not used frequently aerobic bacteria.
• Applied to bioremediation of polychlorinated
biphenyls in river sediments.
• Fungi
• Able to degrade a diverse range of persistent
or toxic environmental pollutants.

19.
How bioremediation work?
• Some living organism can accomplish these
tasks by enzymatically modifying ,oxidising or
decomposing toxic and hazardous using them
as source of carbon and nitrogen.
• Very significant in solving the problem of the
accumulation of non –degradable toxicants in
the environment.

20.
Based on Types of Degradation:
So, based on the principle of degradation,
bioremediation is of two types;
Biotransformation
In the biotransformation process, various
organic components are partially
degraded, and the remaining portion is
transformed into various other organic
matters.
Biomineralization
Biomineralization is another type of
bioremediation where microorganisms
digest and convert organic waste nutrients
into inorganic materials like water, carbon
dioxide, etc.

21.
Advantages
• Environment friendly technology.
• It is useful for the complete degradation of a
wide varity of contaminants.
• Ideal waste treatment method.
• Not cause disruption of normal activities.
• Even without transferring contaminants from
one place to another,bioremediation can
destroy the target chemicals.

22.
Disadvantages
• Very costly.
• Labour-intensive.
• May take several months for desired result.
• Microbial population require suitable
environmental growth condition.

23.
References
1. Stanley.E.Wedberg (Microbes and you)
2. https://www.degruyter.com/document/doi/10.1351/pac200
173071163/html
3. https://www.cabdirect.org/cabdirect/abstract/19981905867

24.
THANKYOU
Presented by,
Delrose Thomson