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CAPSTONE PROJECT
COOLING WATER AND TREATMENT PLANT FOR POWER PLANT
UNDER GUIDENCE OF
DR. Y.S GOEL SIR
A ONE YEAR PROJECT REPORT
PROJECT COMPLETED: - HALF (AFTER ONE SEM.)
SUBMITTED TO: SUBMITTED BY:
MR HIMANSHU KAUSHAL (MENTOR) OMKAR KUMAR JHA - 10902923 DEPT. OF MECHANICAL ENGINEERING (M3904) SHEKHAR PATAKU - 10902017 Sig: PRANAV KUMAR - 10903323 ……………………………………………………………..
LOVELY PROFESSIONAL UNIVERSITY
PHAGWARA (PB)
1
CERTIFICATE
This is to certify that.................................... Bearing Registration no. ......................
Has completed capstone project titled,
“............................................................................................” Under my guidance
and supervision. To the best of my knowledge, the present work is the result of
their original investigation and study. No part of the dissertation has ever been
submitted for any other degree at any University.
The dissertation is fit for submission and the partial fulfillment of the conditions
for the award of partial degree
Signature and Name of the Research Supervisor
Designation
School
Lovely Professional University
Phagwara, Punjab.
Date:
2
DECLARATION
We hereby declare that each contents of this project report are our own. Anything
here mentioned is for educational purpose; hence some contents are being
taken/analyzed from data from internet, Tata steel, books etc. So, there for, it is
solely dedicated to the project guide, student and Lovely Professional University,
under department of mechanical engineering (M3904) for capstone project
purpose.
- OMKAR KUMAR JHA
- PRANAV KUMAR
- SHEKHAR PATAKU
3
ACKNOWLEDGEMENT
First of all, On behalf of the Department of Mechanical Engineering (M3904), we
wish to extend our heartfelt gratitude to LOVELY PROFESSIONAL
UNIVERSITY, PHAGWARA (PB) for giving the opportunity to get familiar with
and conduct project work. We took this opportunity to convey our sincere thanks
to Mr. Manish Gupta (COD-S) for providing guidance, moral support and
modalities to conduct this project.
We would like to thank our Mentor Mr. Himanshu Kaushal for coordinating and
helping us during the project. We also extend our sincere thanks to all other
officials of LPU for providing valuable information and their inputs for the study
over project to us. We would like to express our thanks to all the people at LPU
and MECHANICAL SCHOOL as well who made our project duration very
pleasant and comfortable and for all their hospitality extended to us.
We sincerely thank to all the people who have given a lot of effort by guiding the
project for so many days.
-Thanks and Regards
4
TABLE OF CONTENTS
1. INTRODUCTION
2. THE PROJECT
3. PROJECT PHASES
4. CHEMICAL AND REACTIONS
5. ANALYSIS
6. DESIGN
7. CALCULATION
8. CONCLUSIONS/FUTURE
9. REFRENCES
5
INTRODUCTION
In this academic year 2011-12, we have to submit a capstone project on any
engineering application based project. According to curriculum it is mandatory to
complete a working project to understand the necessity of real time problems
which are not mentioned in general study content.
Water, obviously is a basic human need. Providing safe and adequate quantities of
the same for all rural and urban communities is perhaps one of the most important
undertakings, for the public works Dept. Indeed, the well planned water supply
scheme is a prime and vital element of a country's social infrastructures as on this
peg hangs the health and wellbeing of its people.
The population in India is increasing , with an estimated 40% of urban population.
This goes on to say that a very large demand of water supply; for Domestic,
Industrial, Firefighting, Public uses, etc.; will have to be in accordance with the
rising population. Hence, identification of sources of water supply, there
conservation and optimum utilization is of aramount importance. The water
supplied should be 'Portable' and 'Wholesome'. Absolute pure water is never found
in nature, but invariable contains certain suspended, colloidal, and dissolved
impurities (organic and inorganic in nature, generally called solids), in varying
degree of concentration depending upon the source. Hence treatment of water to
mitigate and lor absolute removal of these impurities (which could be; solids,
pathogenic micro-organisms, odor and taste generators, toxic substances, etc.)
become indispensable. Untreated or improperly treated water becomes unfit for
intended use proves to be detrimental for life.
The designed water treatment plant has an experimental setup as the basic source
of water. The type of treatment to be given depends upon the given quality of
water available and the quality of water to be served. However such an extensive
survey being not possible in the designed water treatment plant but somehow the
data has been taken and collected from different sources. It is assumed that all
kinds of treatment processors are necessary and an elaborate design.
So hereby we 3 classmate decided to construct a working model of a water
treatment plant on small scale with some new techniques which can further
attached to power plant for their cooling water necessity as well.
6
This project is decided because in daily life we encountered with so many
problems regarding water recycling, reuse and treatment. For this we have also
setup so many plants which can do all the operations indeed. But in real time we
have to setup new plant for each operation separately because of their certain
limitations like space availability, operating cost, maintenance etc.
This prospective proposal of project can remedies the entire problem and can
produce single point output station of the water having less energy consumption
for different uses which are further explained in details.
7
THE PROJECT
The project is solely based on the working of the water treatment plant. In water
treatment process, we generally treat water for drinking purpose but here in this
project not only we will produce drinking water but also water used for other
purposes like industrial as well as power plant based cooling water which is high
grade water having no salt or other additive dissolved into it. Because if there will
be any contaminant there it may cause the rust, blast or other accidental cases due
to unwanted particles.
In other ways or words treatment is mainly based upon removal of unwanted
particles from raw water so this removal depends upon our need .where we want to
use or product and how much efficiency we need to develop upon it.
For good performance of the product we have to ensure about its all quality and
services. Like how much is this acidic or basic in nature, how much contaminant it
includes in itself. For good reason of required criteria we have to identify pros and
cons of the input and output and the process applying as well.
So in water treatment we mainly consider about TURBIDITY, PH, DISSOLVED
PARTICALS, ODOR, COLOR etc. These are the key factors to control the water
quality in output. So for all above quality we have certain procedure and process
which gives us 97% desired output. But for optimum quality of product we can
leave the product in SETTLING TANK for some hours to settle down and then we
can further pump it to stations for other uses.
Corrosion is also a big problem due to chemical mixed in it like Alum, PaCl,
CaOCl, Chlorine Gas etc which can corrode the surface of the pipe if not
controlled. In industry corrosion failure are the one which are occurring every year
at large scale. For this a company has to make certain arrangement like control the
PH value, reserve the inventory of the commonly corrosive components etc.
Water treatment has mainly some initial stages mentioned here with diagram
shown below:
8
PUMP HOUSE
RAW WATER
RESERVIOR
CHEMICAL
MIXING
WATER LAKE/ POND
FILTERED
WATER
CLARIFLOCCULATOR
FILTRATION BED
CHLORINATION
O.H
TANK
DEMINERLIZATION/
REVERSER OSMOSIS/
ION EXCHANGE
BFP
CWPH
CONDE
-NSER
PUMP
HOUSE
COOLING TOWER DISTRIBUTION FOR
DRINKING PURPOSE
Flow Diagram
9
Standard working cycle
First of all the raw water is pumped to mixing channel where it got mixed with
alum for coagulation which make the dissolve particles more heavy and settle them
down to the base. Then the pre chlorination occur, which controls the color and
other bacteria inside the water by adding up continuous amount of chlorine gas into
water .then further water moves to flocculate chamber where flocculation is done.
Means this point rotates regularly and agitates the water to help to settle down the
particles again. Then it further moves to filter house which consist of BED made
by sand 5-6” grits 3-4”,gravels 3-4”, then the big gravels 4-5” in depth. In the
bottom a pipe is fitted to suck the water (clean) .
This pipe is also used for back BED WASH with the help of high jet of air which
vibrates all the particles of bed and removes the contaminants from the sand
surface. Then further treated water moves to post chlorination stage where after
checking all the values (desired as ph, color, odor etc) then adds extra amount of
chlorine gas. Then this final water is sent to settling tank or reservoir where treated
final water is finally taken in rest for at least of 3-4 hours then pumped to different
stations for transporting to different location according to use.
10
PROJECT PHASES
This capstone project is decided for 2 phase 1 sem each. In 1 semester only simple
water treatment will be verified then after in next semester the treated water will be
again treated for power plant with the help of reverse osmosis principle.
In power plant basically water is used for various purposes. All the other purpose
can be solved from the above steps itself but the cooling water or working fluid
cannot be used as same. For this purpose the treated water will be again treated by
some methods like reverse osmosis, ultraviolet treatment, chemical treatment etc.
But our main aim is to control the salt present inside the water. If not then this salt
can corrode the cooling surface of the power plant and can reduce the thermal
efficiency of the cycle by absorbing excess heat.
11
So one stage is to be completed in present semester and the treatment of cooling
and working water will be finalized into next or final semester.
So hereby we are submitting the project in analysis, calculation and design
segment comes under our 1 year project so far.
In this academic session the project has finally reached at the mid evaluation with
above stated criteria and hence submitting the raw data of the ideal plant with
important components likewise...
CHEMICAL AND REACTIONS
Antifoams
Foam is a mass of bubbles created when certain types of gas are dispersed into a
liquid. Strong films of liquid than surround the bubbles, forming large volumes of
non-productive foam.
The cause of foam is a complicated study in physical chemistry, but we already
know that its existence presents serious problems in both the operation of industrial
processes and the quality of finished products. When it is not held under control,
foam can reduce the capacity of equipment and increase the duration and costs of
processes.
Antifoam blends contain oils combined with small amounts of silica. They break
down foam thanks to two of silicone's properties: incompatibility with aqueous
systems and ease of spreading. Antifoam compounds are available either as
powder or as an emulsion of the pure product.
Powder Antifoam powder covers a group of products based on modified
polydimethylsiloxane. The products vary in their basic properties, but as a group
they introduce excellent antifoaming in a wide range of applications and
conditions.
The antifoams are chemically inert and do not react with the medium that is
defoamed. They are odorless, tasteless, non-volatile, non-toxic and they do not
corrode materials. The only disadvantage of the powdery product is that it cannot
be used in watery solutions.
12
Emulsions Antifoam Emulsions are aqueous emulsions of polydimethylsiloxane fluids. They
have the same properties as the powder form, the only difference is that they can
also be applied in watery solutions.
Coagulants
When referring to coagulants, positive ions with high valence are preferred.
Generally aluminium and iron are applied, aluminium as Al2(SO4)3-
(aluin) and
iron as either FeCl3 or Fe2(SO4)3-
. One can also apply the relatively cheap form
FeSO4, on condition that it will be oxidised to Fe
3+ during aeration.
Coagulation is very dependent on the doses of coagulants, the pH and colloid
concentrations. To adjust pH levels Ca(OH)2 is applied as co-flocculent. Doses
usually vary between 10 and 90 mg Fe3+
/ L, but when salts are present a higher
dose needs to be applied.
Corrosion inhibitors
Corrosion is a general term that indicates the conversion of a metal into a soluble
compound.
Corrosion can lead to failure of critical parts of boiler systems, deposition of
corrosion products in critical heat exchange areas, and overall efficiency loss.
That is why corrosion inhibitors are often applied. Inhibitors are chemicals that
react with a metallic surface, giving the surface a certain level of protection.
Inhibitors often work by adsorbing themselves on the metallic surface, protecting
the metallic surface by forming a film.
Organic inhibitors will be adsorbed according to the ionic charge of the inhibitor
and the charge on the surface.
Disinfectants
Disinfectants kill present unwanted microrganisms in water. There are various
different types of disinfectants:
· Chlorine (dose 2-10 mg/L)
· Chlorine dioxide
· Ozone
· Hypochlorite
13
Chlorine dioxide disinfection
ClO2 is used principally as a primary disinfectant for surface waters with odor and
taste problems. It is an effective biocide at concentrations as low as 0.1 ppm and
over a wide pH range. ClO2 penetrates the bacterial cell wall and reacts with vital
amino acids in the cytoplasm of the cell to kill the organisms. The by-product of
this reaction is chlorite.
Chlorine dioxide disinfects according to the same principle as chlorine, however,
as opposed to chlorine, chlorine dioxide has no harmful effects on human health.
Hypochlorite disinfection Hypochlorite is aplied in the same way as chlorine dioxide and chlorine. Hypo
chlorination is a disinfection method that is not used widely anymore, since an
environmental agency proved that the Hypochlorite for disinfection in water was
the cause of bromate consistence in water.
Ozone disinfection Ozone is a very strong oxidation medium, with a remarkably short life span. It
consists of oxygen molecules with an extra O-atom, to form O3. When ozone
comes in contact with odour, bacteria or viruses the extra O-atom breaks them
down directly, by means of oxidation. The third O-atom of the ozone molecules is
than lost and only oxygen will remain.
Disinfectants can be used in various industries. Ozone is used in the
pharmaceutical industry, for drinking water preparation, for treatment of process
water, for preparation of ultra-pure water and for surface disinfection.
Chlorine dioxide is used primarily for drinking water preparation and disinfection
of piping.
Every disinfection technique has its specific advantages and its own application
area. In the table below some of the advantages and disadvantages are shown:
14
Technology Environmentally
friendly
Byproducts Effectivity Investment Operational
costs
Fluids Surfaces
Ozone + + ++ - + ++ ++
UV ++ ++ + +/- ++ + ++
Chlorine
dioxide
+/- +/- ++ ++ + ++ --
Chlorine gas -- -- - + ++ +/- --
Hypochlorite -- -- - + ++ +/- --
Flocculants
To promote the formation of flocs in water that contains suspended solids polymer
flocculants (polyelectrolytes) are applied to promote bonds formation between
particles. These polymers have a very specific effect, dependent upon their
charges, their molar weight and their molecular degree of ramification. The
polymers are water-soluble and their molar weight varies between 105 and 10
6 g/
mol.
There can be several charges on one flocculent. There are cationic polymers, based
on nitrogen, anionic polymers, based on carboxylate ions and polyampholytes,
which carry both positive and negative charges.
Neutralizing agents (alkalinity control)
In order to neutralize acids and basics we use either sodium hydroxide solution
(NaOH), calcium carbonate, or lime suspension (Ca(OH)2) to increase pH levels.
We use diluted sulphuric acid (H2SO4) or diluted hydrochloric acid (HCl) to
decline pH levels. The dose of neutralizing agents depends upon the pH of the
water in a reaction basin. Neutralization reactions cause a rise in temperature.
15
Oxidants
Chemical oxidation processes use (chemical) oxidants to reduce COD/BOD levels,
and to remove both organic and oxidisable inorganic components. The processes
can completely oxidise organic materials to carbon dioxide and water, although it
is often not necessary to operate the processes to this level of treatment
A wide variety of oxidation chemicals are available. Examples are:
· Hydrogen peroxide;
· Ozone;
· Combined ozone & peroxide;
· Oxygen.
Hydrogen peroxide Hydrogen peroxide is widely used thanks to its properties; it is a safe, effective,
powerful and versatile oxidant. The main applications of H2O2 are oxidation to aid
odour control and corrosion control, organic oxidation, metal oxidation and
toxicity oxidation. The most difficult pollutants to oxidize may require H2O2 to be
activated with catalysts such as iron, copper, manganese or other transition metal
compounds.
Oxygen
Oxygen can also be applied as an oxidant, for instance to realize the oxidation
of iron and manganese. The reactions that occur during oxidation by oxygen are
usually quite similar.
These are the reactions of the oxidation of iron and manganese with oxygen:
2 Fe2+
+ O2 + 2 OH- --> Fe2O3 + H2O
2 Mn2+
+ O2 + 4 OH- --> 2 MnO2 + 2 H2O
Species (Other than H2O) Contained in Water
Chemical analysis of virtually any freshwater sample reveals that "water"-- even
water that has been rigorously cleaned and treated-- is really a solution containing
many dissolved species. A solution is a homogenous system (a system that is
uniform throughout) containing more than one substance. A solution in which H2O
is the solvent is known as an aqueous solution. In addition to H2O (which is the
solvent), water samples may include:
ions (e.g., Na+, Ca
2+, F
-, and HSO4
-)
dissolved gases (e.g., O2 and CO2)
16
other natural dissolved molecules (e.g., organic by-products of decaying
leaves)
dissolved molecules from human activity (e.g., industrial and agricultural
wastes)
Reactions are:
Mg2+
(aq) + Ca2+
(aq) + 2 OH-(aq) ---> Mg(OH)2 (s) + Ca
2+ (aq)
From water from lime precipitate
Ca2+
(aq) + Ca2+
(aq) + 2 CO32-
(aq) ---> 2CaCO3 (s)
from water from lime from soda ash precipitate
CO2 (g) + H2O (l) ---> H2CO3 (aq)
H2CO3 (aq) + OH
- (aq) ---> H2O + HCO3
- (aq)
17
ANALYSIS
The treatment plant or any other plant has some criteria to work upon or the certain
condition to follow so that good and efficient working may obtained.
The combination of following processes is used for municipal drinking water
treatment worldwide:
Pre-chlorination: - for algae control and arresting any biological growth
Aeration: - along with pre-chlorination for removal of dissolved iron and
manganese and oxygen.
Coagulation: - for flocculation
Coagulant aids: - also known as polyelectrolyte‟s- to improve coagulation
and for thicker flock formation...
Sedimentation: - for solids separation, that is, removal of suspended solids
trapped in the flock.
Filtration: - removing particles from water
Desalination: -Process of removing salt from the water.
Disinfection: - - for killing bacteria. The above mentioned technologies are
well developed and generalized designs are available which are used by
JUSCO utilities (public or private). In addition to the generalized solutions, a
number of private companies provide solutions by patenting their
technologies.
Final testing: water (treated) is finally checked for its turbidity then sent to
its respective towers or storages.
So hereby some steps of analysis are mentioned so far.
Management of a design project Preliminary studies Basic design procedure and general considerations
Coagulation and chemical application
Flocculation process
Sedimentation (clarification) process
Chemical feed system
Instrument and process control
Disinfection process
Sludge handling and disposal
Intake system/pumping system
18
Flow measurement/piping system
Elements of detailed design
Lime-soda ash softening
Iron and manganese removal
Membrane separation
Overall process design
Water quality results showed high removal rates of turbidity based on the
mechanism of pore size exclusion, these results would indicate that a significant
fraction of matter contributing to turbidity was in the particulate fraction (i.e.,
particle size >0.04 μm. Lower removal rates for organic matter as measured by
TOC indicate that dissolved organic carbon (DOC) may represent a considerable
fraction of the TOC (TOTAL ORGANIC COMPOUND) present in the raw water.
These results are supported by color and technical measurements, for which
Reduced removal rates were achieved with filtration indicating that the
concentration of dissolved organic material in the raw water would warrant pre-
treatment (i.e., coagulation) to enhance overall removal efficiencies. Poly-
aluminum chloride (PACl), ferric salts such as ferric sulphate [Fe(SO4)3] or ferric
chloride (FeCl3), or Synthetic coagulating agents such as poly-acryl amides would
also be Viable coagulants that could be evaluated with this water.
• Particle count analysis: would provide additional data on permeate water quality
in terms of removal of particles within size range of (2 – 15 μm) and other
cryptosporidium, 2 – 5 μm).
As a surrogate monitoring technique, particle counting determines particle
size and thus warns of particles in the size range of 2-6 μm.
• Dead-End Flow Configuration: Recirculation pumps and associated piping is
required resulting in reduced capital costs and operational cost Savings due to
reduced energy input.
19
DESIGN Before END OF SEM. we have completed our design, analysis, calculations phase
for 1st set of project. The design is attached under as created into PRO-E wildfire
v4.0:
SIDE VIEW
Now after midterm the analysis and design work has been done and thereafter the
calculation part also.
In the calculation and analysis phase we have encountered problem related to scale
the prototype of the project related to actual one. The problem faced is totally
genuine in terms of actual cycle of the plant.
As the cycle starts the power input to components and the specific rating of
different component always counter the actual process including overflow, dry run
and so on; . At some stages we found that the water did not clean according to
necessity or the other ratings are not matching with specific data so then re-
consideration of project with recalculation becomes necessary.
SEDIMENTATION
TANK
FINAL STORAGE
OUTPUT WATER
PIPE
20
ROTATING ARM
PUMP 2
CHEMICAL MIXING
CHAMBER
PUMP 1
STORAGE
TANK
POROUS PIPE
FLOCCULATOR
COUNTER AGITATOR
SHAFT
CLOSE BED AREA
GUIDE PIPE
FILTER BED
PUMP 3
MAIN WATER
ENTRANCE PIPE
CHEMICAL DOSER
21
COMPONENTS OF PROPOSED DESIGN
In this project we tried to overcome the energy loss and tried to use the
conventionally available component so that operating and maintenance cost with
setup cost may get reduced.
Due to previous analysis following units are required to be designed for treatment
plant
(1) Intake Structure:
Intake well
Gravity main
Jack well
Rising main
Pump
(2) Treatment unit: Aeration unit
Coagulant dose
Lime soda dose
Chemical dissolving tank
Chemical house
Flash mixer
Clariflocculator
Rapid sand filter
Chlorination unit
(3) Storage unit:
Underground storage tank
Elevated storage
Schematic diagram of each of the unit is shown in THE PROJECT section
22
PUMPS
The following four types of pumps are generally used.
Buoyancy operated pumps
Impulse operated pumps
Positive displacement pumps
Centrifugal pump
The following criteria govern pump selection. : Type of duty required.
Present and projected demand and pattern and change in demand.
The details of head and flow rate required.
Selecting the operating speed of the pump and suitable drive.
The efficiency of the pumps and consequent influence on power
consumption and the running costs.
Losses 𝑓 = 4𝑓𝑙𝑣2
2𝑔𝑑
Total head of pumping = hs + hd + hf + minor losses
Design Criteria for Mechanical Rapid Mix Unit
Velocity of flow = m/sec.
Depth =
Power Required =
Impeller speed =
Loss of head =
Mixing device be capable of creating a velocity gradient
= m/sec/m depth
Ratio of impeller diameter to tank diameter =
(C) Design Calculation
Design flow
Detention time
Ratio of tank height to diameter
Ratio of impeller diameter to tank diameter
Rotational speed of impeller
Assume temperature
= m3/day
23
Design Criteria: (Flocculator)
Depth of tank = Detention time = Velocity of flow =. Total area of paddles =
Range of peripheral velocities of blades = Power consumption = Outlet velocity =
FILTER BED
Design Criteria: (Clarifier)
24
Surface overflow rate = Depth of water =
Weir loading =
Storage of sludge = Floor slope = 1 in 12 or 8% for mechanically cleaned tank.
Slope for sludge hopper =
Scraper velocity = 1 revolution in 45 to 80 minutes Velocity of water at outlet chamber = not more than 40 m/sec.
CALCULATIONS
A sample data is tabulated as under. This tabulation shows the standard
specifications for the specific properties of treated water. This scale is used for
1 MLD of water to be treated on one cycle of plant. So hereby we can scale it
according to our basic need for standard project .
Standard formulas :
Flow of water required = water volume (MLD) * 3600* 24
Volume of well = 𝜋 ⋰ 4𝑑2 ∗ l.57 m3 (Damming‟s standard)
Discharge rate = area * velocity per unit time
Intake well of diameter = d
Power generated =℘𝑔
Velocity obtained = cd 2𝑔
Power output from shaft = 2𝜋𝑛𝑇
60 watt
Cross-sectional area of intake well = 2𝜋𝑟𝑙 Diameter of intake well = (d)
Design of Rapid Gravity Filter:
(a) Rapid Sand Filter
The rapid sand filter comprises of a bed of sand serving as a single medium
granular matrix supported on gravel overlying an under drainage system, the
distinctive features of rapid sand filtration as compared to slow sand filtration
25
include careful pre-treatment of raw water to effective flocculate the colloidal
particles, use of higher filtration rates and coarser but more uniform filter media to
utilize greater depths of filter media to trap influent solids without excessive head
loss and back washing of filter bed by reversing the flow direction to clear the
entire depth of river. .
The removal of particles within a deep granular medium filter such as rapid sand
filter occurs primarily within the filter bed and is referred to as depth filtration.
Conceptually the removal of particles takes place in two distinct slips as transport
and as attachment step. In the first step the impurity particles must be brought from
the bulk of the liquid within the pores close to the surface of the medium of the
previously deposited solids on the medium. Once the particles come closer to the
surface an attachment step is required to retain it on the surface instead of letting it
flow down the filter.
The transport step may be accomplished by straining gravity, setting, impaction
interception, hydrodynamics and diffusion and it may be aided by flocculation in
the interstices of the filter.
(a) Design Criteria: (Rapid Sand Filter) . Rate of filtration = m3//hr
. Max surface area of one bed = m2
o Min. overall depth of filter unit including a free board of 0.5m = m
o Effective size of sand = mm
o Uniformity co-efficient for sand = 1.3 to 1.7 (standard)
. Silica content should not be less than 90%
. Specific gravity =2.55 to 2.65 (standard)
. Wearing loss is not greater than 3%
. Minimum number of units = 2
. Depth of sand = 0.6 to 0.75
. Standing depth of water over the filter = 1 to 2m
. Free board is not less than 0.5m
(b) Problem Statement
Net filtered water
Quantity of backwash water used
Time lost during backwash
Design rate of filtration
Length - width ratio
Under drainage system
26
Size of perforations
Alum Dose:
Coagulation: The terms coagulation and flocculation are used rather indiscriminately to describe
the process of removal of turbidity caused by fine suspension colloids and organic
colors.
Coagulation describes the effect produced by the addition of a chemical to a
colloidal dispersion, resulting in particle destabilization. Operationally, this is
achieved by the addition of appropriate chemical and rapid intense mixing for
obtaining uniform dispersion of the chemical. The coagulant dose in the field
should be judiciously controlled in the light of the jar test values. Alum is used as
coagulant.
Softening Water is said to be hard, when it does not form leather readily with soap.
The hardness of water is due to the presence of calcium and magnesium ions in
most of the cases. The method generally used is lime-soda process. Softening with
these chemicals is used particularly for water with high initial hardness ( > 500
mg/L) and suitable for water containing turbidity, color and iron salts. Lime-soda
softening cannot, however, reduce the hardness to values less then40 mg/L.
Design of Mechanical Rapid Mix Unit
Flash Mixer
Rapid mixing is and operation by which the coagulant is rapidly and uniformly
dispersed throughout the volume of water to create a more or less homogeneous
single or multiphase system.
This helps in the formation of micro floes and results in proper utilization of
chemical coagulant preventing localization of connection and premature formation
of hydroxides which lead to less effective utilization of the coagulant. The
chemical coagulant is normally introduced at some point of high turbulence of
water. The source of water for rapid mixing to create the desired intense turbulence
is gravitational and pneumatic.
The intensity of mixing is dependent upon the temporal mean velocity gradient
„G‟. This is defined as the rate of change of velocity per unit distance normal to a
section. The turbulence and resultant intensity of mixing based on the rate of
power input to the water.
Flash mixture is one of the most popular methods in which the chemicals are
dispersed. They are mixed by the impeller rotating at high speeds
27
Summary
Design of Pen stock And Bell Mouth Strainer
(a) Pen stock This are the pipes provided in intake well to allow water from water body to intake
well. These pen stocks are provided at different levels, so as to take account of
seasonal variation in water level (as H.W.L, M.W.L, and L.W.L). Trash racks of
screens are provided to protect the entry sizeable things which can create trouble in
the pen stock. At each level more than one pen stock is provided to take account of
any obstruction during its operations. These pen stocks are regulated by valves
provided at the top of intake wells.
Design Criteria
Velocity through pen stock
Diameter of each pen stock
Number of pen stock for each intake well
28
After the specific design conditions the special operating conditions are given
below: (in introductory in nature)
Sr.
No
Characteristics Acceptable Cause for
Rejection
1 Turbidity ( scale) 2.5 10
2 Color (platinum cobalt scale) 5 units 25units
3 Taste and odor Unobjectionable Unobjectionable
4 PH 7.0 to 8.5 6.5 to 9.2
5 Total dissolved solids(mg/L) 600-800 1500
6 Total hardness (mg/L as CaC03) 200 600
7 Chlorides (mg/L as C1) 200 1000
8 Sulphate (mg/L as 804) 200 400
9 Fluorides (mg/L as F) 1 1.5
10 Nitrates (mg/L as N03) 22 45
11 Calcium (mg/L as Capacity) 75 200
12 Magnesium (mg/L Mg) 30 150
13 Iron (mg/L Fe) 0.1 1
14 Manganese mg/L as MnO 0.05 0.5
15 Copper (mg/L Cu) 0.05 1.5
16 Zinc (mg/L as Zn) 5 15
17 Lead (mg/L as Pb) 0.002
0.1
18 Anionic Detergents (mg/L as MBAS) 0.01 1
19 Mineral oil (mg/L) 0.01 2
Notes: The figures indicated under the column 'Acceptable' are the limits upon
which water is generally acceptable to the consumers.
Figures in excess of those mentioned under 'Acceptable' render the water not
acceptable, but still may be tolerated in the absence of alternative and better
source upon the limits indicated under column 'Cause for Rejection' above
which the supply will have to be rejected.
It is possible that some mine and spring waters may exceed these
radioactivity limits and in such cases it is necessary to analyze the individual
radio nuclides in order to assess the acceptability for public consumption.
29
Comparison Of Given Data and Standard Data during process cycle
(Totally introductory in nature)
Sr. No Particulars Actual Standard Difference Means for
Treatment 1 pH 7.5 7 to 8.5 O.K Not
necessary
2 Turbidity 50 2.5 47.5 Clarifier &
rapid sand
filter
3 Total Hardness
(mg/L)
550 200 350 Softening
4 Chlorides(mg/L) 120 60-70 50-60 Increase
volume of
water
5 Iron (mg/L) 2.5 0.1 2.4 Aeration
6 Carbonates 110 - - Softening
This data shows at some important stages the failure has been detected at the initial
of plant. So according to scale it may be setup and according to laboratory report
data may calibrated to control the big differences.
Means time this is not an actual calculation of the project hence it can‟t be same in
each case neither it is a standard data or scaled data. This data is only for
understanding the condition in which different steps is to be taken.
30
CONCLUSION
Hence we conclude that this project is very efficient for 1 whole city because it can
complete all the water need of the city itself. It can reduce the other cost and can be
setup in small area which can also graded as low energy consumption unit having
high efficiency.
In this project we have tried to implement the ideas which are easy to use and cost
effective. Further during project it is taken in consideration that the energy
consumption should be lesser as possible.
The efficiency of this project is tried to enhanced with the help of design and
operating conditions like head difference, gravity flow, natural circulation etc with
respect to the conventional operational conditions. These effects may visualize in
final project submission.
Further we would like to include that this project is taken for enhance the working
procedure and efficiency thus the efficiency of plant may increase from 40% to
60% approx.
During process cycle it is mandatory that the water for drinking should be
maintained as “Basic side (PH 7-8.5)” at some point so that it can meet the human
comfort because the human system the controlling of acid base side is very
important which can‟t be neglected for maintaining good drinking grade.
Other benefits are:
o To ensure low cost of treated water
o To reduce water wastage by recycling
o Reduce load of electricity / operating cost
o One point operation
o Low maintenance due to one plant on only one location
o High capacity regarding individual plant
31
Future
In this era of new technology the main consideration is to decrease the total cost
with efficient output. For this a numerous kind of implementation has been made
to the exiting design of plant. The price including into setup defined by the
accuracy and type of output needed from the plant.
As per new policies of Indian government the specific condition of uses of input
energy and the waste should be fruitfully maintained. This can be done by various
kind of implementation such as uses of low power input component and the
conventional system of work. But in the case of good efficiency we have to
compromise with some of the point like enviournment, health, input power, life of
plant etc. which maybe counter by the hierchy policies applied over the industry.
So all this condition may reduce the efficiency of the plant or output , thus a
efficient plant must contains good quality of output in terms of less input and
wastage as well.
So in future water, as it is a essential item for life, is very important and much
more needed thing to live. So good and required quality may obtained by efficient
process and technical help.
So as a engineer it is very important to use good and low waste component and
process to increase efficiency, the day by day regular increment in quality system
is necessary.
32
REFRENCES
Dr. Y.S Goel sir (DEAN)
Mr. Himanshu kaushal (Mentor)
Tata steel (JUSCO)
web page :www.wikipedia.org
Text book : Power plant Engineering ( Tata McGraw hills pub)
Text book: P.K NAG
PRO-E Wildfire v4.0 (for modeling)
Articles published in wordpress.com, scribed.com
http://www.lenntech.com/products/chemicals/water-treatment-
chemicals.htm#ixzz1emcAngX1
http://www.chemistry.wustl.edu/~edudev/LabTutorials/Water/PublicWat
erSupply/PublicWaterSupply.html
Project report submitted by IIT Delhi , Mumbai and others for the same
Recommended