Transcript Click to add title - University of Cincinnati

Biology: November 5th, 2008
• Objectives:
Develop and understand the importance of
wastewater treatment
• Things to do:
Pick up the worksheets
Fill out Assessment sheet and turn it in
Experience the waste of water
Jeopardy
• Due Dates:
Brochure 11/18/2008
Wastewater treatment
How humans make use of nature
Amr Safwat – STEP 2008-2009
Brochure
Due Date: 11/18/2008
• Definition of Wastewater
• Materials in Wastewater
• How can wastewater be cleaned
• What is a wastewater treatment plant
• How can we reduce our wastewater
• Lab results
• Future technlogies
• References
Outline
1. What is wastewater?
2. Where does the wastewater go?
3. What is a wastewater treatment pant?
4. Wastewater treatment steps
5. Biological treatment & Bacteria
6. Who works at a treatment pant?
3. Cincinnati Wastewater Treatment Pants
What is Wastewater?
• Wastewater is a liquid waste,
which consists of animal,
vegetable, mineral or chemical
matter in solution or in
suspension with water
• It comes from residents and
businesses who flush different
matter + water down their toilets
or pour it down their sinks and
drains
Where does wastewater go?
• Wastewater drains into a
network of pipes maintained by
the local sewer service
municipalities
• Sewer systems are built to
collect and flow wastewater and
rainwater using the natural slope
of land, generally towards the
sea front or to wastewater
treatment plants
What is a wastewater treatment
plant (WWTP)?
• A WWTP is the place where wastewater is
treated to prevent contamination and
destruction of our waterways, and our
natural water resources
• It includes physical, chemical and
biological processes to remove physical,
chemical and biological contaminants
Water Treatment
1. Screening &
Filtering
1
2
2. Sedimentation
3
3. Filtration
5
4
4. Aeration
5. Chlorination
Water Treatment
1. Screening
2
2. Grit Chamber
1
3
3. Primary
4
5
Sedimentation
4. Aeration Tank
5. Secondary
Sedimentation
Wastewater treatment steps
Step 1
Step 2
Step 3
Primary
treatment:
Secondary
Treament:
Tertiary
Treatment:
Includes
romvoval of
large objects
some solid
materials like
debrit, gravel,
sand or liquids
like fats, oils and
grese from the
water
Includes
degradation of
biological
content of the
sewage such
as are derived
from human
waste, food
waste, soaps
and detergent
Includes a final
treatment to
effluent (water)
to increase the
water quality,
before the
water is
discharged to
the natural
waterways
Biological treatment?
• In the aeration tanks
microorganisms and
wastewater are mixed,
aerated, and maintained
in suspension (activated
sludge)
• In the secondary clarifier
solids are removed and
the activated sludge is
returned to the aeration
tanks
Biological treatment?
• The effluent (out-flowing water) from the primary
treatment stage is send to the secondary stage
were the water is biologically treated
• Most treatment plants use an aerobic biological
process, for which bateria are used
• Some bacteria (unicellular microorganisms)
need oxygen and orbanic matter to live
Bacteria
•
•
•
•
Bacteria are simple, colorless, onecelled plants that use soluble food
and are capable of self-reprodcution
without sunlight
There are two main groups: aerobic
and anaerobic. They can be found
everywhere in soil, acidic hot springs,
water, in animals, plants and in our
body. There are one million bacterial
cells in one mL of fresh water
Bacteria are considered as
decomposers due to their
indispensable ecological role of
decaying organic matter in nature
Humans make use of this by using
them in secondary treatment stage to
decompose organic matter in
wastewater
Perfect Water Cycle –
Eco-Boulevards
* Source: pruned.blogspot.com
Who works at WWTP?
• Civil engineers plan and design many parts of a
WWTP
• Chemical engineers design the primary and secondary
stages and they also make sure that the cleaned water
has a certain quality before it is discharged
• Microbiolologists make sure that enough bacteria and
oxygen is provided
WWTP in Cincinnati
• There are 10 wastewater
treatment plants in the greater
Cincinnati area. They collect 200
million gallons of wastewater
every day
• The Sycamore Creek Wastewater
Treatment Plant was originally
built in 1957 with a design
average treatment capacity of 1
million gallons per day (MGD).
Since that time, the plant has
been expanded three times (1966,
1970 and 1991) to increase
treatment to its present capacity of
~20 MGD*
* Source: MSD website
Jeopardy
Why do we need to learn about wastewater?
a)
b)
c)
d)
Jeopardy
How do we use bacteria in a wastewater treatment plant?
a)
b)
c)
d)
Jeopardy
How is water cleaned in the secondary treatment stage?
a)
b)
c)
d)