S3 SEWAGE STORAGE, TREATMENT AND DISPOSAL Assignment
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Transcript of S3 SEWAGE STORAGE, TREATMENT AND DISPOSAL Assignment
APPRECIATION
Assalamualaikum…
Praise is presented only for ALLAH Almighty Disposer of all things. Peace and
blessings be upon beloved Prophet Muhammad leaflets bearing the revelation to
illuminate be universe, the companions, his family, all the scholars and lovers of Islam
throughout the world.
Thank God, that we can complete this assignment work to be handed over to Mr.
Huzaime b. Abdul Hadi very well. From making this assignment, we can add our
knowledge about the sewage storage, treatment and disposal.
Lastly, we would like to thank Mr. Huzaime b. Abdul Hadi. He has been providing
guidance and information on how to produce this work. Thank you also to friends who
also give lessons and share ideas and information.
Sewage storage, treatment and disposal | 1
INTRODUCTION
All sewage should be drained and treated with proper disposal.For the planned
development, sewage treatment plant will discharge into a centralized to the treatment
works prior to disposal.While for the area or areas otherwise limited, would waste
treated on site or collected while and then transported to the treatment plant.
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1. Distinguish between the role of anaerobic and aerobic bacteria in the
breakdown of domestic sewage.
Anaerobic are caused by anaerobic bacteria. Anaerobic bacteria do not grow on
solid media in room air (10% carbon dioxide and 18% oxygen); facultative anaerobic
bacteria can grow in the presence as well as in the absence of air. Microaerophilic
bacteria do not grow at all aerobically or grow poorly, but grow better under 10% carbon
dioxide or anaerobically. Anaerobic bacteria can be divided into strict anaerobes that
can not grow in the presence of more than 0.5% oxygen and moderate anaerobic
bacteria that are able of growing between 2 to 8% oxygen.[1] Anaerobic bacteria usually
do not possess catalase, but some can generate superoxide dismutase which protects
them from oxygen.
An aerobic organism or aerobe is an organism that can survive and grow in an
oxygenated environment. Faculitative anaerobes grow and survive in an oxygenated
environment and so do aero tolerant anaerobes.
One area of sewage treatment that is not well understood is the bacterial
decomposition process.
Bacteria may be aerobic, anaerobic or facultative. Aerobic bacteria require
oxygen for life support whereas anaerobes can sustain life without oxygen. Facultative
bacteria have the capability of living either in the presence or in the absent of oxygen. In
the typical sewage treatment plant, oxygen is added to improve the functioning of
aerobic bacteria and to assist them in maintaining superiority over the anaerobes.
Agitation, settling, pH and other controllable are carefully considered and employed as a
means of maximizing the potential of bacterial reduction of organic in the wastewater.
Single-celled organisms grow and when they have attained a certain size, divide,
becoming two. Assuming an adequate food supply, they then grow and divide again like
the original cell. Every time a cell splits, approximately every 20 to 30 minutes, a new
generation occurs. This is known as the exponential or logarithmic growth phase. At the
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exponential growth rate, the largest number of cells are produced in the shortest period
of time. In nature and in the laboratory, this growth cannot be maintained indefinitely,
simply because the optimum environment of growth cannot be maintained. The amount
of growth is the function of two variables: - environment and food. The pattern which
actually results is known as the bacterial growth rate curve. Initially dehydrated products
(dry) must first re-hydrate and acclimate in a linear growth phase before the exponential
rate is reached.
Microorganisms and their enzyme systems are responsible for many different
chemical reactions produced in the degradation of organic matter. As the bacteria
metabolize, grow and divide they produce enzymes. These enzymes are high molecular
weight proteins.
It is important to recognize the fact that colonies of bacteria are literally factories
for the production of enzymes. The enzymes which are manufactured by the bacteria
will be appropriate to the substrate in which the enzyme will be working and so you
have automatic production of the right enzyme for the biological reduction of any waste
material, provided you have the right bacteria to start with. Enzymes do not reproduce
whereas as bacteria do.
Enzymes in biochemical reactions act as organic catalysts. The enzymes actually
become a part of the action, but after having caused it, split off from it and are
themselves unchanged. After the biochemical reactions are complete and products
formed, the enzyme is released to catalyze another reaction. The rate of reaction may
be increase by increasing the quantity of the substrate or temperature up to a certain
point , but beyond this, the rate of reaction ceases to increase because the enzyme
concentration limits it.
All treatment plants should be designed to take advantage of the decomposition
of organic materials by bacterial activity. This is something you can equate to lower
costs, increased capacity, and an improved quality of effluent; even freedom from bad
Sewage storage, treatment and disposal | 4
odors which may typically result when anaerobe bacteria become dominant and in their
decomposition process, produce hydrogen sulfide gas and similar by-products.
Consider the fact that the total organic load of wastewater or sewage is
composed of constantly changing constituent, it would be quite difficult to degrade all of
these organics by the addition of one enzyme, or even several enzymes. Enzymes are
specific catalysts and do not reproduce. What is needed is the addition of an enzyme
manufacturing system right in the sewage that can be pre - determined as to its activity
and performance and which has the initial or continuing capacity to reduce waste.
At the present time, the addition of specifically cultured bacteria seems to be the
least expensive and most generally reliable way to accomplish desirable results. When
you add the right bacteria in proper proportions to the environment, you have
established entirely new parameters of potential for the treatment situation.
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2. Describe the construction of :
a. A Septic Tank
Is a tool for collection and disposal of waste in site sewage permit process
anaerobik.it decomposed to from solid sludge,scum and liquid.Period form of
treatment among 16-48 hours from the tank emptied between 12-36 months.
Figure 1 A Septic Tank
Characteristics of the Design and Development
Capacity
total kapasity, c = 180P + 2000 => liter
if the food chopper is used:
c = 250P + 2000 => liter
depth = 1.5-1.8 m =
if one part: length x width
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Measurement
if two parts: (for users of> 100 persons)
part 1: length = 2 x width (C = 2/3 C.total)
Part 2: length = width (C = 1/3 C total)
Construction
engineering brick (200mm)
concrete cast there (150mm)
unit pre-cast septic
b. A Biological Filter
A sewage treatment prior to dispose of waste water in drains or other.
Figure 2 A Biological Filter
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Characteristics of the Design and Development
Capacity
1 m ^ 3 / head ...... for users 1-10 people
0.8m ^ 3 / head ...... for users 1-50 people
0.6m ^ 3 head .... for users 1-100 people
Construction
Square with an open stream if the user up to 50
people.
Are round with a drop of the flow distribution if the
number of users exceeds 50 people
The inside is filled with coarse gravel.
The depth Minimum = 1.8 m
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3. Compare the various combination and shapes of septic tank
There are many different septic tank designs and although they may look
different or be different shapes and sizes they all work basically the same way.
Below you will see a picture of the basic internal design of a septic tank.
Figure 3 Septik tank
Compartment Septic Tank
The effluent comes in through the pipe on the left and is deposited into the main
chamber of the septic tank. If the solids are denser than water they will fall straight to
the bottom of the tank and the less dense solids and the greases will float at the
surface. The solids that sink to the bottom right away are digested by bacteria and the
same goes for the solids that float on top. Bacteria can digest most of the organic
matter in human effluent but they cannot digest all of it. The materials that they cannot
digest settle to the bottom of the septic tank and we call this material sludge. It is the
sludge that is pumped during routine septic tank maintenance. Grease and other
insoluble materials will stay afloat on the surface of the tank. The water in the tank is
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not pure water, it is called gray water because it still contains organic materials that
need to be filtered out. As more water enters the effluent pipe coming from your house
the water level inside the septic tank rises and gray water will exit through the sewage
pipe on the right and head towards the drainage field.
There are generally three access ports at the top of the septic tank. The access
port in the middle is what a septicpumping service would open when they are going
to pump out the septic tank. The other two ports are located directly above the
incoming pipe and the outgoing pipe. They provide easy access in case one of the
pipes is blocked or clogged.
Your septic tank may also have two different compartments. It is designed this
way so that the sludge remains predominantly on one side of the tank so that it does
not make its way into the sewage pipe that goes the drainage field. If the sludge builds
up high enough so that it does enter the drainage tube and goes the drainage field,
you are going to have some major septic tank problems in the near future.
Below you will see a schematic of a septic tank and a drainage field.
Figure 4 Septic System & Drain Field
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As you can see in the diagram, the tube that leaves the septic tank goes to a
pipe system which is called the drainage field. The pipe system is perforated to allow
the gray water to exit and it exits into a specifically created soil bed of crushed rock
and other ingredients. If the sludge from the septic tank makes its way into the
drainage field it can clog these perforated tubes and end up causing major damage.
This can lead to septic system failure which is something that you definitely want to
avoid.
In the diagram below you will see what happens to the water when it leaves the
drainage field.
Figure 5 Septic Tank Greywater Filter
The gray water that leaves the perforated tubing in the drainage field either
goes up to the surface in small amounts and is evaporated or filters its way through
the ground. As the water makes its way through the ground it becomes more and more
clean and by the time it reaches the groundwater it is once again drinkable. You will
notice in the diagram that there is a well and that is where the filtered water will end
Sewage storage, treatment and disposal | 11
up. Anyone who lives on a well should have their water tested regularly
for bacteria because if there is bacteria in the water that means your septic system is
failing. If you discover that your septic system is failing you need to address the
problem immediately.
There are other septic tank designs, most notably an aerator septic tank. The
design of the aerator septic tank is basically the same as a traditional septic tank. The
major difference is that there is a mechanism that introduces air into the gray water
inside the septic tank. This allows for aerobic bacteria to digest the human effluent
rather than anaerobic bacteria that are found in traditional septic tanks. The reason
this is important is because aerobic bacteriawork a lot faster than anaerobic bacteria.
See the diagram below for an example of a basic aerobic septic systemdesign.
Figure 6 Aerobic Septic System
Essentially the septic tank is just a holding area for human affluence while it is
being degraded. So it could even be in the shape of an airplane, as long as it does
what it is supposed to do; the shape and actual design of the septic tank does not
really matter. The design of the standard septic tank is usually a concrete box because
that is the easiest to build and cheapest to manufacture and it works. Considering the
job it is supposed to do and the fact that it is buried in the ground the actual look of the
septic tank is of no consequence.
Sewage storage, treatment and disposal | 12
4. Compare the various methods of distributing septic tanks
There are many different types of septic systems. Some of them include pressure
distribution, sand filter, mound, and gravity. This article will discuss some of the different
types of septic systems.
Gravity
One of the first types of septic systems use gravity to drain wastewater from the
tank into a series of trenches. Because this system works using gravity, the
drainage field must be below the level of the septic tank. Also, the bottom of the
trenches must be three or four feet above the water table. This soil above the
water table is used to treat the wastewater before it returns to the environment.
Pressure Distribution
One of the next types of septic systems uses pressure distribution. This system
has a pump that distributes wastewater evenly throughout the drainage field. The
pump tank holds wastewater until a certain point before it releases it into the
drainage field. Pressure distribution systems are normally used when there is not
enough soil depth to accommodate gravity-based systems.
Sand Filter
Sand filter systems are also one of the most common types of septic systems.
This system uses sand between the pump tank and the drainage field. The sand
is used to treat the wastewater before it enters the field. These types of septic
systems are used when there is very shallow soil. Treating the wastewater with
sand makes up for the lack of soil that would normally be used to treat the waste.
Sewage storage, treatment and disposal | 13
Mound
One of the next types of septic systems is the mound design. This system is also
used when the soil isn't deep enough for a traditional system. These types of
septic systems have a sand-filled mound raised over the natural soil above a
drainage field. The wastewater is treated as it travels through the sand and into
the natural soil.
Aerobic
One of the more unconventional types of septic systems is the aerobic design.
The system is equipped with a watertight tank that has an aeration chamber.
Waste is broken down by bacteria in the aeration chamber. These systems are
capable of producing cleaner wastewater, so they are commonly used in
sensitive environments.
These are some of the different types of septic systems. One of the most
common types uses gravity to drain wastewater from the tank into a series of trenches.
There are also aerobic systems that use bacteria to break down the sewage. These
types of septic systems are commonly used in sensitive environments.
Sewage storage, treatment and disposal | 14
5. Use formula and information given in the current Code of Practise, to
determine the size of a septic tank and biological filter.
Example 1
Calculate the size of the septic tank and biological filter for an on-site sewage treatment
system that provides services to 100 people.
Solution
A) Septic tank
Total capacity = 180 p + 2000 P = Number of population
= 180 (100) + 2000
= 20 000 liter 20 000/1 000
C = 20m 3
From the table, assuming the septic tank is divided into two parts and it is
rectangular in shape.
Capacity part of A
A = 2/3 total capacity (C) (From table)
V = 2/3 X 20
V = 13.33M 3 (Volume)
From the table = consider the Wide (A) Length (2L) X Width (L) and the High
(H) = 1.5 meter
Sewage storage, treatment and disposal | 15
V = AH
V = 2L X L X 1.5
V = 3L2
13.33 = 3L2
L2 = 13.33
3
L = 4.44
L = 2.108 meter (width)
Because of the length = 2 X Width
= 2 X 2.108
Length = 4.216 meter
Capacity part of B
B = 1/3 total capacity (C)
V = 1/3 X 20
V = 6.67m 3 (Volume)
From the table, consider the Wide (A) Length = Width and High (H) = 1.5
meter
V = AH
V = L X LX 1.5
V = L2 X 1.5
6.67 = L2 X 1.5
L2 = 6.67
1.5
Sewage storage, treatment and disposal | 16
L = 6.67
1.5
L = 2.108 meter (Width)
As P = L
Length = 2.108 meter
B) Biological filter
From the table, consider biological filter with depth round = 1.8 meter (H)
Capacity = 0.6 m3 X number of population
= 0.6 X 100
V = 60 m 3 (Volume)
V = AH
V = j2 X 1.8
60 = j2 X 1.8
60 = 3.14j2 X 1.8
3.14j2 = 60
1.8
3.14j2 = 33.33
j2 = 33.33
3.14
j2 = 10.61
Sewage storage, treatment and disposal | 17
j = 10.61
j = 3.25 meter
2 X J = 2 (3.5)
D = 6.5 meter
j = ½ D
Area of circle = j2 X Height
= d2 X Height
4
V = AH
V = d2 X 1.8
4
60 = 3.14 D2 X 1.8
4
240 = 3.14 D2 X 1.8
3.14 D2 = 240
1.8
Sewage storage, treatment and disposal | 18
3.14 D2 = 133.3
D2 = 133.3
3.14
D2 =42.45
D = 42.45
D = 6.515 meter
Sewage storage, treatment and disposal | 19
CONCLUSION
The conclusion from completing this assignment, we can identify clearly about
sewage storage, treatment and disposal. All sewage should be drained and treated
with proper disposal. For the planned development, sewage treatment plant will
discharge into a centralized to the treatment works prior to disposal. Anaerobic
bacteria usually do not possess catalase, but some can generate superoxide
dismutase which protects them from oxygen.
An aerobic organism or aerobe is an organism that can survive and grow in an
oxygenated environment. Faculitative anaerobes grow and survive in an oxygenated
environment and so do aerotolerant anaerobes. There are many different septic tank
designs and although they may look different or be different shapes and sizes they all
work basically the same way. Compare the various methods of distributing septic
tanks.
There are many different types of septic systems. Some of them include
pressure distribution, sand filter, mound, and gravity. This article will discuss some of
the different types of septic systems. And the last is formula for size of a septic tank,
biological filter.
Page | 20
REFERENCES
1. Jousimies-Somer HR, Summanen P, Baron EJ, Citron DM, Wexler HM,
Finegold SM. Wadsworth-KTL anaerobic bacteriology manual. 6th ed.
Belmont, CA: Star Publishing, 2002.
2. ^ Brook, I.: “Anaerobic Infections Diagnosis and Management”. A Textbook.
Informa Healthcare USA, Inc. New York. 2007.
3. ^ Nagy E. Anaerobic infections: update on treatment considerations. Drugs.
2010;70:841-58
4. ^ Hentges DJ. The anaerobic microflora of the human body . Clin Infect Dis
1993;164:S175–80.
5. ^ Brook, I.: “Anaerobic Infections Diagnosis and Management”. A Textbook.
Informa Healthcare USA, Inc. New York. 2007.
6. ^ Jousimies-Somer HR, Summanen P, Baron EJ, Citron DM, Wexler HM,
Finegold SM. Wadsworth-KTL anaerobic bacteriology manual. 6th ed.
Belmont, CA: Star Publishing, 2002.
7. "aerobe" at Dorland's Medical Dictionary
Page | 21