Wastewater treatment is a process used to remove contaminants from wastewater and convert it into an effluent that can be returned to the water cycle. Once returned to the water cycle, the effluent creates an acceptable impact on the environment or is reused for various purposes (called water reclamation). The treatment process takes place in a wastewater treatment plant. There are several kinds of wastewater which are treated at the appropriate type of wastewater treatment plant. For domestic wastewater (also called municipal wastewater or sewage), the treatment plant is called a sewage treatment plant. For industrial wastewater, treatment either takes place in a separate industrial wastewater treatment plant, or in a sewage treatment plant (usually after some form of pre-treatment). Further types of wastewater treatment plants include agricultural wastewater treatment plants and leachate treatment plants.

1. Recent challenges and
trends in waste
wastewater Treatment
Manahil Khanam Durrani

2. What is wastewater?
• Wastewater is the polluted form of
water generated from rainwater
runoff and human activities. It is also
called sewage.
• It is typically categorized by the
manner in which it is generated—
specifically, as domestic sewage,
industrial sewage, or storm sewage
(stormwater).

3. Wastewater
Treatment
It’s the journey to treatment and return to the
environment

4. Wastewater
contaminants
•Suspended solids
•Biodegradable Organics
•Pathogenic Bacteria
•Nutrients (N&P)

5. Where does
wastewater
comes from?
• Residence
• Human and animal excreta and
waters used for washing, bathing
and cooking.
• Commercial Institution
• Dairy & industrial establishment
• Slaughterhouse waste, Dairy Waste,
Tannery waste etc.

7. Parameters
considered
measuring
the chemical
characteristic
s of
wastewater
Biochemical oxygen demand (BOD)
Chemical oxygen demand (COD)
Total solids (TS)
Volatile solids (VS)
Total nitrogen (TN)
Total phosphorus (TP)
pH and Alkalinity

8. Levels of Wastewater
Treatment
• Primary wastewater treatment
• Secondary wastewater treatment
• Tertiary wastewater treatment

9. Primary wastewater treatment
wastewate
r is
temporaril
y held in a
settling
tank
where
heavier
solids sink
Once settled,
these
materials
are held
back while
the
remaining
liquid is
discharged
or moved
through to

10. Secondary wastewater treatment
works on a
deeper
level than
primary
and is
designed to
substantiall
y degrade
the
biological
content of
Completing
secondary
wastewater
treatment
allows for
safer
release into
the local
environme
nt,
reducing

11. Secondary
wastewater
treatment
It is done in one of three ways
• Biofiltration
• Aeration
• Oxidation ponds

12. Tertiary wastewater
treatment
• Raise the quality of the water to domestic and
industrial standards
• Meet specific requirements around the safe
discharge of water.
• In the case of water treated by
municipalities, tertiary treatment also
involves the removal of pathogens, which
ensures that water is safe for drinking
purposes.

14. Emerging trends in
wastewater Treatment
Technologies

15. Emerging trends in
wastewater Treatment
technologies
• One of the primary reasons that has driven the inception
of new or improved wastewater treatment technologies
is the legislation and hefty fines that are attracted when
the disposal of wastewater does not meet the set
discharge limits.
• This impact on the financial wellbeing of factories and
industries has fueled the emergence of new or improved
treatment technologies.

16. Advance Technologies
Emerging technologies, that are
used for wastewater treatment are
• MembraneTechnologies
• Reverse and forward osmosis
• Electro-dialysis (ED) and electro-
dialysis reversal (EDR)
• Ion exchange membranes
• Microalgal
• Microbial fuel cell (MFC)
technologies..

17. Challenges in Wastewater
Management

18. Challenges in
Wastewater
Management
• Advances in technology have begun to make these processes more
streamlined than ever.
• These advances do not mean that there are not challenges to overcome
when it comes to wastewater management.
• Following are major challenges in wastewater management
• Energy Usage. ...
• Staffing Issues. ...
• Sludge Protection. ...
• Treatment Plant Environmental Footprint.

19. Energy Usage
• Energy requirements necessary to
operate a wastewater treatment
plant is one of the biggest
challenges they face.
• The wastewater filtration process
consumes between 3 and 15% of
the nation’s electricity annually.

20. Staffing Issues
• Similar to other industries, finding
qualified plant operators has become a
challenge. Properly trained workers skilled
in the process of wastewater treatment is a
must.
• There are not enough employees to go
around. Another aspect of this issue is that
typically treatment facility operator
management can account for up to 30% of
annual operational costs.

21. Sludge Protection
• Sludge is the residue generated during
wastewater treatment. A major
challenge environmentally for
wastewater treatment facilities is how to
dispose of this excess sludge produced
during the process.
• Safe and long term solutions for sludge
disposal is an essential component of
any properly operating treatment
facility.
• Sludge can be recycled and used in
agricultural applications because it
contains organic matter and nutrients
useful to agriculture.

22. Treatment Plant
Environmental Footprint
• There have been recent
improvements in green
technology that improve
the way water is being
treated.
• These innovations will help
reduce the environmental
footprint left behind by
water treatment facilities
from disposal of what is
left behind after clean
water has been discharged.

23. Wastewater
Treatment
From waste to
Resource