Hydraulic Design of Sewer:
Hydraulic formulae, maximum and minimum velocities in sewer, hydraulic
characteristics of circular sewer in running full and partial full conditions,
laying and testing of sewer, sewer appurtenances and network.
Here you will get all information about sewer design, its type & various tests carried out on it for any leakage or any obstruction present and of improper joints.
This presentation includes the estimation of storm sewage generated as a result of storm/rainfall events. It includes the detailed usage of rational formula for quantity estimation with solved examples.
Here you will get all information about sewer design, its type & various tests carried out on it for any leakage or any obstruction present and of improper joints.
This presentation includes the estimation of storm sewage generated as a result of storm/rainfall events. It includes the detailed usage of rational formula for quantity estimation with solved examples.
Lecture notes of Environmental Engineering-II as per Solapur university syllabus of TE CIVIL.
Prepared by
Prof S S Jahagirdar,
Associate Professor,
N K Orchid college of Engg and Technology,
Solapur
supplying wholesome water to consumers with suitable methods in economical way,to exist human life water is very important as air is,so,as a civil engineer's we have to supply safe water to consumers in economical way,in this we are going to explain about component parts of water supply scheme,systems of water distribution and layouts of distribution system according to their suitability.
Lecture notes of Environmental Engineering-II as per Solapur university syllabus of TE CIVIL.
Prepared by
Prof S S Jahagirdar,
Associate Professor,
N K Orchid college of Engg and Technology,
Solapur
water demand, types of demand, factors affecting per capita demand, design periods, losses in wastes & thefts, varion in demand, coincident draft,effect of variations on components of water supply schemes, factors affecting design periods, population forecasting methods, problems on population forecasting, etc
Present slideshow provides brief introductory part of various Intake Structures. This is useful for Environmental Engineering Students, faculties and learners.
Lecture notes of Environmental Engineering-II as per Solapur university syllabus of TE CIVIL.
Prepared by
Prof S S Jahagirdar,
Associate Professor,
N K Orchid college of Engg and Technology,
Solapur
supplying wholesome water to consumers with suitable methods in economical way,to exist human life water is very important as air is,so,as a civil engineer's we have to supply safe water to consumers in economical way,in this we are going to explain about component parts of water supply scheme,systems of water distribution and layouts of distribution system according to their suitability.
Lecture notes of Environmental Engineering-II as per Solapur university syllabus of TE CIVIL.
Prepared by
Prof S S Jahagirdar,
Associate Professor,
N K Orchid college of Engg and Technology,
Solapur
water demand, types of demand, factors affecting per capita demand, design periods, losses in wastes & thefts, varion in demand, coincident draft,effect of variations on components of water supply schemes, factors affecting design periods, population forecasting methods, problems on population forecasting, etc
Present slideshow provides brief introductory part of various Intake Structures. This is useful for Environmental Engineering Students, faculties and learners.
Sewage Treatment Plant Treatment For WastewaterKaleem
In this presentation you seen how sewage treatment plant work and its processes. In this presentation we covered all process of sewage treatment plant. If you have any doubt then you can visit web portal of tradeindia and get all details from there.
MicroFAST® - Advanced Waste Water Treatment SystemJane Fenway
MicroFAST® wastewater treatment system provides unique waste water solutions for decentralized homes, clustered subdivisions, and commercial properties around the world.
Shubham Inc, wastewater treatment plants for residential government and municipal and commercial applications.
By considering environmental responsibility towards water, Shubham Inc.has forayed into Water and Sewage Water Treatment Plants. Shubham‘s product range is mainly split into two market verticals Water Treatment & Waste Water Treatment.
Lecture notes of Environmental Engineering-II as per Solapur university syllabus of TE CIVIL.
Prepared by
Prof S S Jahagirdar,
Associate Professor,
N K Orchid college of Engg and Technology,
Solapur
Effluent treatment plant - design, operation and analysis of waste water trea...Shubham Hydrosys Pvt. Ltd
The Effluent Treatment Plants [ETP] plant is designed to treat the effluent coming from various areas of the plant. The treatment of different effluents varies with the type of effluent. Industrial wastewater contains a diversity of impurities and therefore for this reason alone, its treatment establishes a special task. Shubham Inc. offers comprehensive range of Effluent Treatment Plants that is highly effective.
The complete treatment solution works at many levels and comprises of different physical, chemical, biological and membrane processes. For reducing the BOD, COD, color, nitrogen and toxic level of the effluent, SHUBHAM is offeringa various solutions from ASP (activated sludge process) to advance Membrane technologies as per treated water uses.Shubham OffersCustomized systems to suit the extensive variety of effluents and to maintain efficiency are provided to industries.
We provide innovative and economical systems for waste withexpertise is advantageously employed for the technical and economic optimization of every subsequent facility.
SHUBHAM INC use the best-in-class technology and cutting-edge tools to foster high-quality, sustainable, community-level water supply sewage treatment plant and Effluent Treatment Plants projects in Gujarat, India across the ahmedabad, Surat, Rajkot and Baroda.
Some processes followed by us are:
• Aerobic Biological Process
• Anaerobic Biological Process
• Chemical-physical process
TREATMENT REQUIREMENTS:
1. Oil & grease Separation
2. Neutralization of Acids and Alkali
3. Removal of Suspended Solids
4. Reduction & Removal of metallic impurities
5. Reduction of high organic content: BOD, COD, P, TKN, etc.
6. Dissolve impurities for ZLD system.
TREATMENT METHODS
• Primary clarifications
• Biological process
• Secondary clarifications.
• Tertiary treatment
• Polishing units i.e. UF, RO and DM (Optional for recycling or ZLD)
Applications:
• Textile Industries
• Distilleries
• Pharmacy Industries.
• Chemical Industries
• Paper Industries
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• Edible Oil Refineries
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Features:
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I was asked to provide current markups of the electrical drawing set. The problem was that much of the equipment had been upgraded with no drawing supplied by the contractor. There was also no drawing standards at the time, so I quick created a new numbering system and block templates.
See my LinkedIn post for more info;
https://www.linkedin.com/today/post/article/project-2-sewer-treatment-plant-electrical-drawings-david-list?trk=prof-post
Short power point showing wet well mounted pump station attributes. Smith & Loveless built a trailer with this station on it and we are traveling around the province showing it to many operators and consultants.
Transport of Pollution in Atmosphere: Plume behaviour under different atmospheric
conditions, Mathematical models of dispersion of air pollutants, Plume behaviour in valley and terrains. Plume behaviour under different meteorological conditions, Concept of isoplates
Air Pollution control- at source-equipments for control of air pollution-For particulate matter-Settling chambers-Fabric filters-Scrubbers-Cyclones-Electrostatic precipitators
, For Gaseous pollutants-control by absorption-adsorption-scrubbers-secondary combustion after burners, Working principles advantages and disadvantages
Effects of Air Pollution on human beings, plants and animals and Properties. Global
effects-Green house effect, Ozone depletion, heat island, dust storms, Automobile pollution sources and control, Photochemical smog, Future engines and fuels
Air Quality Sampling and Monitoring: Stack sampling, instrumentation and methods of analysis of SO2, CO etc, legislation for control of air pollution and automobile
pollution
History of Air pollution and episodes, Sources of air pollution and types, Introduction
to meteorology and transport of air pollution: Global winds, Headley cells, wind rose terrestrial wind profile, Effects of terrain and topography on winds, lapse rate, maximum mixing depths, plume rise
Definition, Composition of atmospheric air, Classification and sources of air
pollutants. Effects of air pollution on human, plant and material, Air pollution control methods, equipment and safety.
Levels in planning, Functional requirements of water resources projects, steps in
water resources planning, Environmental aspects in water resources planning.
Definition of drought, Causes of drought, measures for water conservation and
augmentation, drought contingency planning. Water harvesting: rainwater
collection, small dams, runoff enhancement, runoff collection, ponds, tanks.
Canal fall- necessity and location- types of falls- Cross regulator and
distributory head regulator- their functions, Silt control devices, Canal
escapes- types of escapes.
Types- selection of the suitable site for the diversion headwork components
of diversion headwork- Causes of failure of structure on pervious foundation- Khosla’s theory- Design of concrete sloping
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Introduction:
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Water requirements of crops:
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Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
Andreas Schleicher presents at the OECD webinar ‘Digital devices in schools: detrimental distraction or secret to success?’ on 27 May 2024. The presentation was based on findings from PISA 2022 results and the webinar helped launch the PISA in Focus ‘Managing screen time: How to protect and equip students against distraction’ https://www.oecd-ilibrary.org/education/managing-screen-time_7c225af4-en and the OECD Education Policy Perspective ‘Students, digital devices and success’ can be found here - https://oe.cd/il/5yV
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
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The map views are useful for providing a geographical representation of data. They allow users to visualize and analyze the data in a more intuitive manner.
1. Module III
Hydraulic Design of
Sewer
Bibhabasu Mohanty
Asst. Prof.
Dept. of civil Engineering
SALITER, Ahmedabad
2. Course content…
Hydraulic formulae, maximum and
minimum velocities in sewer, hydraulic
characteristics of circular sewer in
running full and partial full conditions,
laying and testing of sewer, sewer
appurtenances and network.
3. Design of Sewers
The hydraulic design of sewers and drains, means
finding out their sections and gradients, is generally
carried out on the same lines as that of the water
supply pipes.
However, there are two major differences between
characteristics of flows in sewers and water supply
pipes.
4. The sewage contain particles in suspension, the
heavier of which may settle down at the bottom of the
sewers, as and when the flow velocity reduces, resulting
in the clogging of sewers.
To avoid silting of sewers, it is necessary that the sewer
pipes be laid at such a gradient, as to generate self
cleansing velocities at different possible discharges.
5. The sewer pipes carry sewage as gravity conduits, and
are therefore laid at a continuous gradient in the
downward direction up to the outfall point, from
where it will be lifted up, treated and disposed of.
6. Hydraulic formulae
1. Chezy’s formula
where
V= is the mean velocity [m/s],
C= is the Chézy coefficient [m½/s],
R= is the hydraulic radius (~ water depth) [m],
i= is the bottom slope[m/m].
Constant (C) is very complex. Depends on size,
shape and smoother roughness of the channel,
the mean depth etc.
C can be calculated by using Bazin’s formula.
7. 2. Bazin’s formula Where,
C = 157.6 K= Bazin’s constant
[1.81 + (K/R1/2)] R= hydraulic radius
Sr. No. Inside nature of the sewer K values
1. Very smooth 0.109
2. Smooth: bricks & concrete 0.290
3. Smooth: rubble masonry 0.833
4. Good, earthen material 1.540
5. Rough: bricks & concrete 0.500
6. Rough earthen material 3.170
8. 3. Manning’s formula
V = velocity of flow (m/s)
k =conversion factor of 1.486 (ft/m)1/3
n =Manning coefficient
Rh = hydraulic radius (m)
S = slope of the water surface
* The value of “n” is calculated by kutter’s formula
9. 4. Kutter’s formula
Where
C = Chézy's roughness coefficient
S = Friction slope
R = Hydraulic radius (m,)
n = Kutter's roughness (unit less)
k1 =Constant (23.0 SI,)
k2=Constant (0.00155 SI,)
k3= Constant (1.0 SI,)
10. 5. Hazen – William’s formula
where:
V is velocity
k is a conversion factor for the unit system k = 0.849 for
SI units)
C is a roughness coefficient
R is the hydraulic radius
S is the slope of the energy line (head loss per length of
pipe )
11. 6. Crimp and Burge’s formula
V = 83.47 R 2 / 3 S 1/ 2
Where,
V = velocity of flow (m/s)
R = hydraulic radius (m)
S = slope of the water surface
12. Minimum Velocity
The flow velocity in the sewers should be such that the
suspended materials in sewage do not get silted up; i.e.
the velocity should be such as to cause automatic self-
cleansing effect.
The generation of such a minimum self cleansing
velocity in the sewer, at least once a day, is
important, because if certain deposition takes place
and is not removed, it will obstruct free flow, causing
further deposition and finally leading to the complete
blocking of the sewer.
13. Self clearing velocity
To calculate minimum velocity of flow following
formula is used.
V=
where,
V= minimum velocity of flow in m/s.
k= size of solids in sewage varying between 0.06mm
f= Darcy’s coefficient of friction (normally 0.03)
14. es= specific gravity of solid material flowing in
sewage, varies between 1.2 to 2.65
e= specific gravity of liquid in sewage (generally
1)
g= gravitational acceleration cont.
ds= dia of solid particles in mm
15. Maximum Velocity
The smooth interior surface of a sewer pipe gets
scoured due to continuous abrasion caused by the
suspended solids present in sewage.
It is, therefore, necessary to limit the maximum
velocity in the sewer pipe. This limiting or non-
scouring velocity will mainly depend upon the material
of the sewer.
16. Effects of Flow Variation on Velocity in a
Sewer
Due to variation in discharge, the depth of flow varies,
and hence the hydraulic mean depth (r) varies.
Due to the change in the hydraulic mean depth, the
flow velocity gets affected from time to time.
It is necessary to check the sewer for maintaining a
minimum velocity of about 0.45 m/s at the time of
minimum flow (assumed to be 1/3rd of average flow).
17. The designer should also ensure that a velocity of 0.9
m/s is developed at least at the time of maximum flow
and preferably during the average flow periods also.
Moreover, care should be taken to see that at the time
of maximum flow, the velocity generated does not
exceed the scouring value.
18.
19.
20.
21. Laying of Sewer
The basics of laying a residential sewer is lateral in the
ground.
You will need a starting elevation and an ending
elevation.
After the trench is excavated, when entering an open
trench, the pipe layer prepares the trench bottom by
removing loose dirt and grading the trench bottom to
allow for proper flow of sewage within the pipe.
22. You need to ensure that the material beneath the pipe
is solid so that the pipe does not "sag" after it is
backfilled.
Typically if the "original" ground beneath the new pipe
is not disturbed and graded properly, the pipe will be
adequately supported.
If the original ground is over excavated, however, you
will need to install compacted sand or gravel bedding
beneath the pipe in order to support it.
23. Once the ground is prepared, you lay the pipe on the
prepared soil.
In most cases, you should start on the low end of the
run and work your way up to the connecting point.
If you use "hub" pipe, that is, pipe with an integral pipe
built into the pipe, you should lay your first pipe
beginning on the low end of the run with the hub on
the uphill side of the pipe.
24. If you are using PVC pipe, both ends of the pipe
should be primed with purple primer prior to laying
it.
To connect the two ends of the pipe, you apply glue
to the male and to the female ends of the pipe, being
careful to not allow dirt to stick to the glued ends of
the pipe.
Insert the male end into the female end and spin the
pipe.
Hold the two pipes in place for ten seconds to ensure
that they do not come apart.
25. Once the pipes are connected, you are ready to "bed"
the pipe.
This means that you should place sand or gravel
around and over the pipe - enough to just cover the
top of the pipe.
Once this is complete, you compact the granular
material around the pipe.
It is important to pay attention to this compaction
process so that the pipe does not lift while you are
compacting.
26. Once the bedding process is complete, you are ready
to move on the next pipe.
It is important to note that as you install more pipe,
you should be backfilling the trench behind you up to
a safe level.
27.
28.
29. Testing of sewer
The testing of sewers is necessary as any leakage,
improper joints, straightness or obstruction of sewers
may occur during laying of sewers.
These defects may be removed or repaired after
detection.
So there are various tests by which these defects may
be detected. These tests are :-
31. Water Test
This test is carried out for sewer lines between two
manholes.
Plugging is done by rubber plug at its lower end.
Rubber plug is connected with air blown.
The upper end of sewer is plugged with a connection
to the funnel.
The sewer is filled with water and to maintain the
required head, water level in the funnel is kept 2 m
above the upper end.
32. This head varies with the material of sewer.
In case of cast iron sewer, the head should be at 9m.
The acceptable loss or head loss should not exceed 2
litres/cm of length of the sewer.
To perform this test sufficient amount of water should
be available.
33.
34. Acceptable water loss
Max loss
Pipe Dia per metre
[mm] in 30 mins
[litres]
100 0.05
150 0.08
225 0.11
300 0.15
400 0.20
450 0.23
500 0.25
600 0.30
750 0.38
>750 seek advice
35. Air Test
When sufficient amount of water is not available,
then air test is to be carried out.
36. Air is pumped into the pipeline, usually via a hand-
pump with a control valve, until the reading on the
manometer is around 125-150mm.
The set-up is then left for 5-10 minutes to allow for
temperature stabilisation within the pipe before the
pressure is reduced to exactly 100mm on the
manometer scale.
The manometer is then monitored for a period of 5
minutes; the level of water in the manometer should
not fall below the 75mm mark during this period.
37. This is deemed to be a 'pass' and the pipeline is
declared satisfactory and can be backfilled.
However, if the level in the manometer does fall
below the 75mm mark, then the equipment should be
checked and cleaned and the pipeline examined for
leaks or defects.
If any problems are identified, they should be
rectified before re-testing.
38. Smoke Test
The purpose of smoke testing is to find potential
points of inflow and infiltration in the sanitary sewer
system that could lead to high flows during a storm.
Smoke testing forces smoke-filled air through a
sanitary sewer line.
39. The smoke under pressure will fill the main line plus
any connections and then follow the path of any leak
to the ground surface, quickly revealing the source of
the problem.
Only enough force to overcome atmospheric pressure
is required.
40. Test For Obstruction
For straightness or obstruction of pipe, this test can be
used. There are many methods for obstruction or
straightness :
1. To check the obstruction of sewer pipe, a ball of
suitable diameter is rolled down from upstream side.
The diameter of ball should be less then the diameter
sewer. If there is no obstruction, the ball can be taken
out at downstream side.
41. 2. The straightness can also be checked by placing a
lamp at one end and a mirror at the other end.
If the full circle of light is visible at other end, then the
sewer is straight and there is no obstruction.
If there is any obstruction within the sewer line, it can
also be traced out.
42. Sewer Appurtenances
Sewer appurtenances are the various accessories on
the sewerage system and are necessary for the efficient
operation of the system.
They include man holes, lamp holes, street inlets,
catch basins, inverted siphons, and so on.
43. Man-holes: Man holes are the openings of either
circular or rectangular in shape constructed on the
alignment of a sewer line to enable a person to enter
the sewer for inspection, cleaning and flushing.
They serve as ventilators for sewers, by the provisions
of perforated man-hole covers.
Also they facilitate the laying of sewer lines in
convenient length.
Man-holes are provided at all junctions of two or more
sewers, whenever diameter of sewer changes,
whenever direction of sewer line changes and when
sewers of different elevations join together.
44.
45.
46. Special Man-holes
Junction chambers: Man-hole constructed at the
intersection of two large sewers.
Drop man-hole: When the difference in elevation of
the invert levels of the incoming and outgoing sewers
of the man-hole is more than 60 cm, the interception
is made by dropping the incoming sewer vertically
outside and then it is jointed to the man-hole chamber.
47.
48. Flushing man-holes: They are located at the head of a
sewer to flush out the deposits in the sewer with water.
Lamp-holes: Lamp holes are the openings constructed
on the straight sewer lines between two man-holes
which are far apart and permit the insertion of a lamp
into the sewer to find out obstructions if any inside the
sewers from the next man-hole.
50. Street inlets: Street inlets are the openings through
which storm water is admitted and conveyed to the
storm sewer or combined sewer. The inlets are located
by the sides of pavement with maximum spacing of 30
m.
51. Catch Basins: Catch basins are small settling chambers
of diameter 60 - 90 cm and 60 - 75 cm deep, which are
constructed below the street inlets. They interrupt the
velocity of storm water entering through the inlets and
allow grit, sand, debris and so on to settle in the basin,
instead of allowing them to enter into the sewers.
52. Inverted siphons: These are depressed portions of
sewers, which flow full under pressure more than the
atmospheric pressure due to flow line being below the
hydraulic grade line.
They are constructed when a sewer crosses a stream or
deep cut or road or railway line.
To clean the siphon pipe sluice valve is opened, thus
increasing the head causing flow.
Due to increased velocity deposits of siphon pipe are
washed into the sump, from where they are removed.