WASTEWATER TREATMENT

1. Lecture 1
Wastewater
Engineering:
Overview
Instructor
Dr. Sarah Farrukh
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2. Course Contents
 Water Issues: Current Status and the Role of Water
Reclamation and Reuse
 Water Reuse: Past and Current Practices
 Health and Environmental Concerns in Water Reuse
 Technologies and Systems for Water Reclamation and
Reuse
 Removal of Residual Particulate Matter
 Different Filtration Technologies (lab scale, Pilot plants)
 Reutilization of Water
 Case Studies/ Published papers
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3. Books
Water Reuse Issues , Technologies and
Applications by MetCalf &Eddy
Membrane Processes for Water Reuse
1st Edition by Anthony Wachinski
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4. Part 1: Water Reuse: An
Introduction
 It is important to understand the concept of
sustainable water resources management as a
foundation for water reclamation and reuse. It will
include current and potential future water shortages,
principles of sustainable water resources management,
and the important role of water reclamation and reuse
are introduced briefly.
 The past and current practices of water reclamation
and reuse are presented, which also serve as an
introduction to the subsequent engineering and water
reuse applications.
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5. Part 2: Health and Environmental
Concerns in Water Reuse
Health and environmental issues related to
water reuse are discussed in Part 2. The
characteristics of wastewater are introduced,
followed by a discussion of the applicable
regulations and their development. Because
health risk analysis is an important aspect of
water reuse applications, Lectures will be
devoted to this subject including tomethods
used in risk assessment, chemical risk
assessment, and microbial risk assessment.
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6. Part 3: Water Technologies and
Systems for Water Reclamation
and Reuse
The various technologies and systems available
for the production and delivery of reclaimed
water are the subject of Part 3. Although design
values are presented, detailed design is not the
focus of these chapters. Rather, the focus is on
the dependable performance of the processes
and technologies. Detailed discussions are
provided with respect to constituents of concern
in water reuse applications including particulate
matter, dissolved constituents, and pathogenic
microorganisms.
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7. Part 4: Water Reuse Applications
Because water quality and infrastructure
requirements vary greatly with specific water
reuse application, major water reuse applications
are discussed in separate in Part 4: no potable
water reuse applications including agricultural
uses, landscape irrigation, industrial uses,
environmental and recreational uses,
groundwater recharge, and urban nonpotable
and commercial uses.
Indirect and direct potable reuses are discussed
with several notable projects.
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8. PRINCIPLES OF SUSTAINABLE WATER
RESOURCES MANAGEMENT
Historically, water resources management has
focused on supplying water for human
activities, with an intrinsic assumption that
technological solutions would keep pace with
steadily increasing water demands and
progressively more stringent water quality
requirements.
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9.  Past water resources development was based on
manipulating the natural hydrological cycle by
attempting to balance the inherent water availability in
a region with societal needs for water in the context of
the social and economic background of the region,
population, and the extent of urbanization.
 Because of the social, economic, and environmental
impacts of past development and the prospects of
potential water shortages, a new paradigm for water
resources development and management is evolving,
based on the principles of sustainability.
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10. Hydrological cycle
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11. The Principle of Sustainability
“Humanity has the ability to make development
sustainable to ensure that it meets the needs of
the present without compromising the ability of
future generations to meet their own needs.”
Sustainability is becoming a driving principle of
political, economic, and social development and
it has achieved considerable public acceptance;
however, the debate still continues over just what
is to be sustained, how, and for whom.
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12. Impacts of water
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13. Disputes on Water
Dispute over water in the Nile Basin. ...
Water shortages and public discontent in Yemen.
...
Turkey, Syria and Iraq: conflict over the
Euphrates-Tigris. ...
Transboundary water disputes between Afghanis
tan and Iran. ...
Dam projects and disputes in the Mekong River
Basin. ...
Dispute over water in the Cauvery Basin in India.
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14. Media Projection
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16. In 2015, NASA's satellite data revealed that 21 of
the world's 37 large aquifers are severely water-
stressed. With growing populations, and
increased demands from agriculture and
industry, researchers indicated that this crisis is
only likely to worsen.
 Clean Energy….Clean Environment.. Clean Water
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17. Water Conservation
Water conservation has been viewed
historically by the water industry as a standby
or temporary measure that is utilized only
during times of drought or other emergency
water shortages.
This criteria changed…..
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19. Water Reclamation and Reuse
Water reclamation is the treatment or
processing of wastewater to make it reusable
with definable treatment reliability and
meeting water quality criteria.
Water reuse is the use of treated wastewater
for beneficial uses, such as agricultural
irrigation and industrial usage.
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20. Water Reclamation and Reuse
Treated municipal wastewater represents a
more reliable and significant source for
reclaimed water as compared to wastewaters
coming from agricultural return flows, storm
water runoff, and industrial discharges.
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26. Current and Potential Future
water shortage
The total volume of renewable freshwater in
the global hydrologic cycle is several times
more than is needed to sustain the current
world population.
However, only about 31 percent of the annual
renewable water is accessible for human uses
due to geographical and seasonal variations
associated with the renewable water
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27. The world population in 2002 was estimated
at 6.2 billion with an annual growth rate of 1.2
percent, or 77 million people per year.
To put the recent growth in perspective, the
world population in the year 1900 was only
1.6 billion and in 1950 it was 2.5 billion. It is
projected that the world population in 2050
will be between 7.9 billion and 10.3 billion
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29. Population in metropolitan cities
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30. Pakistan….
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31. Implementation Hurdles
While water reclamation and reuse is a
sustainable approach and can be cost-effective in
the long run, the additional treatment of
wastewater beyond secondary treatment for
reuse and the installation of reclaimed water
distribution systems can be costly and energy
intensive as compared to such water supply
alternatives as imported water or groundwater.
Furthermore, institutional barriers as well as
varying agency priorities can make it difficult to
implement water reuse projects in some cases.
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32. Public Support
The public’s awareness of sustainable water
resources management is essential; thus,
planning should evolve through a community
value-based decision-making model.
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33. Advances in Water Reclamation
Technologies
Cost-effective and reliable water reclamation
technologies are vital to successful
implementation of water reuse projects.
Comprehensive research on advanced
treatment technologies and their
combinations, including membrane processes,
advanced oxidation, and reliable disinfection
is essential
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34. Wastewater Reclamation and
Reuse
Conventional technologies for water and
wastewater treatment may be incapable of
reducing levels of trace contaminants up to
the desired concentration levels;
Therefore new technologies that offer
significantly improved levels of treatment
need to be tested and evaluated
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35. Wastewater Reclamation and
Reuse
Technologies for water reuse applications:
Membranes (pressure driven, membrane bioreactors)
Carbon adsorption
Advanced oxidation
Ion exchange
Air stripping
Membranes are most significant development for
treatment applications; Membranes produce high
quality treated effluent suitable for reclamation
Wastewater reclaimed with membrane technology can
be effectively used for indirect potable applications
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37. Grading Policy
► Mid term: 30%
► Final: 40-50%
► Assignments: 10-15%
► Quizzes: 10-15%