2. What is water?
Water is the chemical substance with chemical formula H2O:
one molecule of water has two
hydrogen atoms covalently bonded to a single oxygen atom.
Water has no color, appearance and taste.
3D STRUCTURE OF WATER
3. Why need water?
Water is very important for life. We need water to quench our thirst, to
wash our hands, to cook, to water plants and many other things. What
other important uses of water do we have? Without water, the plants
would die and people and animals would get thirsty.
Source of water
Source water is untreated water from streams, rivers, lakes or
underground aquifers that is used to provide public drinking water, as
well to supply private wells used for human consumption. Some water
treatment is usually necessary, so public utilities treat most of the
drinking water before it enters the home. However, the cost of this
treatment, as well as the risks to public health, can be reduced by
protecting source water from contamination.
Businesses and individuals can also take actions to protect drinking
water sources. Businesses can institute management practices to
reduce their use of harmful contaminants or ensure their wastes do not
discharge into ground or surface water.
Why need water treatment?
Some of ingredients in sources water contain at high concentration,
those ingredients are risk for public health and not suitable for
manufacturing of beverages. So before use ground water must be
assure that is risk free for public health.
For assuring drinking water free from risky and before provider to
consumer must be need treatment of sources water.
4. What is RO?
Reverse osmosis (RO) is a water purification process and
dissolved inorganic solids (such as salts) are removed from a
solution (such as water) in which water is forced through a semi-
permeable membrane that removes 90-99% of tap water
impurities. The result is water that is free of minerals and other
contaminants.
Why RO?
Now in a present world RO is only water treatedment system which
reduces TDS from water. Hard of RO system is RO membrane because
not only TDS of feed water reduces by Ro membrane but also all
undesirable ingredients reduce from water. Better RO membrane
better RO system.
Everything have limitation as like as Ro membrane limitation i that it
very sensitive with some metal, cation, anion and microbial such as
Chlorine, iron, Mn, Silicate, sulfate; Yeast, mold, TBC etc.
So, before entry feed water into RO membrane need to remove this
metal, ion and microbial by several steps.
Why we use RO System?
TBL according to PepsiCo International always recommended to
consumers for giving better quality and achieve 100% satisfaction. Now
in a present Bangladesh TBL is highly promoted PepsiCo International
franchisees Beverages Production Company. In beverages sector most
uses raw materials is water, so without pure water is not possible to
satisfy consumers. Those causes TBL use RO System.
Shortly represent the raw water treatment by RO system given below-
5. RO WATER TREATMENT FLOW CHART
2%Citric
Acid
ACF 32M3
/H
2% Anti
Scaling
Bore Well 100M3
R.W. Buffer Tank
For RO Plant (4Nos)
20M3
R.W. Tank 200M3
4-6ppm CL2
Sand Filter 32M3
/H
Polisher
-02
24M3
UV
24M3
RO Membrane
RO Rejectwater
100
M.F.
Storage
Tank
15M3
Polisher
-01
ETPEnvironment
100 M.F.
1) PET LINE & GRB
2) SYRUP ROOM &
3) CIP
2%
Caustic
6. Bore Well
With help of submersible pump surface water with drawn and storage
for purification before drinking and other purpose.
Because of in nature, it is never found in pure form, rather it always
contains "contaminants and by water analysis measures substances
dissolved in water. These contaminants result in water characteristics
such as hardness, electrical conductivity, corrosiveness, etc. Some of
the substances in water pose a health risk when present in certain
quantities.
TBL submersible pump capability 100M3
/H
Care of Bore Well:
Daily sanitize with 200ppm chlorine and electric and mechanical care.
Raw water Storage Tank
For purification after withdrawn by bore well water need to storage
and their start primary purification.
Ca (OCl) Cl + H2O = Ca(OH)2 + Cl2
Cl2 + H2O = HCl + HOCl
In storage tank two types purification is happen
1) Water Soluble Fe2+
converts to insoluble Fe3+
by oxidizing with free
chlorine treatment (chlorine, ozone, Chlorine dioxide and
compressed air.)
7. 2) Primary disinfection with free chlorine treatment. Free Chlorine is
primary anti-microbial agent.
TBL Raw water tank storage capacity 200m3
Care of Raw Water Tank: Every 3monthly cleaning and sanitizing.
:
8. Strainers
A coarse strainer including a removable basket screen with 50 to100
mesh is positioned at the intake point of surface water to remove larger
particulate matter and to protect downstream equipment (e.g. pumps)
from fouling which might lead to damage.
Basket Strainer screen
9. Sand filter
The sand filter is built on mechanical filtration principle. It
uses qualified quartz sand as filtration medium to effectively
remove suspended solid (Fe3+), colloid, and so on.
Note: In back wash time water flow increase gradually, otherwise
possibility to damage the uniformity of sand layer and go out the
sand with backwash water).
Structure of Green sand:
Greensand is a processed material consisting of nodular
grains of the zeolite mineral glauconite. The material is
coated with manganese oxide. The greensand will
remove iron better, as manganese zeolite supplements
the natural aeration of the water, helping to precipitate
the iron.
Sand Filter work Flow:
1st
oxidation by removal of Fe aeration and oxidizing agents (O2,
Cl2, O3, KMnO4), and oxidized iron will then precipitate on a sand
filter.
Fe+2
oxidation → Fe+3
precipitation → Fe(OH)3/Fe2O3
Changing Frequency: after 3years/ depends on performance of filter.
Check Regularly: 1) Activeness of filter i.e; removing capacity of iron.
1) Inlet and outlet pressure gauge difference i.e; filtration ability of
sand filter it measuring by check flow rate.
10. Care of MSF:
When Sand layer is saturated, it is possible to conduct back
washing to regenerate absorptive capacity of Sand layer;
backwash will be done by water and by air more on iron removal
capacities. If output water cannot satisfy rated requirements,
change the medium. Use steam/ Chlorination to sterilize Sand
layer monthly.
Regeneration of sand filter:
Regeneration of Manganese sand filter done with KMnO4.
11. Activated Carbon Filter
Active carbon filters to remove organism particle and chloride
residue.
HOCl + C* = HCl + C*O
Hypochlorous acid + carbon surface = Hydrochloric
acid + carbon surface oxide
A gram of activated carbon can have a surface area in excess of 500M2
,
with 1500M3
being readily achievable.
Care of ACF:
When bed layer is saturated, it is possible to conduct back
washing to regenerate absorptive capacity of active carbon. If
output water cannot satisfy rated requirements, change the
medium. Use steam to sterilize active carbon weekly.
Note: In back wash time water flow increase gradually, otherwise
possibility to damage the uniformity of sand layer and go out the
sand with back wash water).
Changing Frequency: Every year/ depends on performance of filter.
Check Regularly: 1) Activeness of filter i.e; removing capacity of
Chloride residue.
2) Inlet and outlet pressure gauge difference i.e; filtration ability of
carbon filter it measuring by check flow rate.
12. Chemicals Dosing
Operation of the RO system perform improving with following
chemicals-
1) Acids :
Acids (HCl,H2SO4) are injected into the RO feed water to lowered
the pH.reducing the feed water pH is to reduce the potential of
calcium carbonate scaling.
3) Caustic:
Caustics (NaOH) injected to increase the RO feed pH. Caution is
required in raising the feed water pH as it can decrease the
solubility of iron, manganese, and calcium carbonate.
4) Antiscalants:
Antiscalants are a family of chemicals designed to inhibit the formation
and precipitation of crystallized mineral salts that form scale. Scaling
of an RO membrane may occur when sparingly soluble salts are
concentrated in the RO element beyond their solubility limit.
Sparingly soluble salts are listed below in the order of decreasing
scaling problem:
CaCO3 Calcium carbonate > CaSO4 Calcium sulfate > Silica (SiO2) >
SrCO3 Strontium Carbonate > BaSO4 Barium sulfate > SrSO4
Strontium sulfate > CaF2 Calcium fluoride > CaSiO3 Calcium
silicates > MgSiO3 Magnesium silicates > Ca3(PO4)2 Calcium
Phosphate > Fe(OH)2 Iron Hydroxide
Scale inhibitors (anti-scalants) are precipitation process of
sparingly soluble salts to suspended absorbed salt crystals
surfaces. In this situation the crystals size grow to the
concentration sufficient to suspend.
13. MICRON POLISHER
The 5µ micro cartridge filter is set up in RO system to stop micro
particles entering RO membrane. Microfiltration (commonly
abbreviated to MF) is a type of physical filtration process where a
contaminated fluid is passed through a special pore-sized membrane to
separate microorganisms and suspended particles from process liquid.
This filter is made by PP (polypropylene filter medium) series
material.
The polypropylene Cartridges filter is to trap coarser particles toward the
outside of the wall and the finer particles toward the inner wall. Graded-
density filters have a higher dirt-holding capacity and longer effective
filter life than depth filters with single-density construction.
Note: per 10 Inch of every cartridge filter able to filtrate 5 gallon per
minute water. We use 14 number cartridges filters, therefore total
filtrate ability of cartage filter is
5gpm × 4 ×14= 280gpm=1.06M3
/m=63.6M3
/H
Cartridges filter holding must be in stainless steel body.
Care of MP:
Cleaning/washing Frequency: Monthly (S.S. body cleaning with
RO water / 80˚C hot water and hand brash).
Changing Frequency: Monthly/ pressure difference between
.07MPa=0.7 Bar=10.15Psi /micro problem)
14. UV Light
UV is the secondary disinflationary, this unit confirm enter or no
microbial into RO membrane.
No change and cleaning of the UV LIGHT shelf life of RO
membrane decrease. Because of RO membrane very sensitive
with microbial.
Check Regularly: 1) Activeness of UV Light check by calibration of
radiation frequency and check the microbial after UV.
Note: Above 98% Micro Organisms killed.
15. RO Membrane
RO system uses RO membrane to remove ions, suspended solid,
and impurity in water. Under a certain pressure, membrane can
separate incoming water into two parts: one is purified water, and
the other is concentrated water with salt, solid residue.
Note: Performances of RO membrane depend on the temperature,
pressure and TDS of feed water.
Active parts:
Outer layer – Poly Amide,
Middle layer- Polysulfone Layer
Inner layer- Poly Ester Base (Two materials make up the bulk of
commercial RO membranes, cellulose acetate and an aromatic
polyamide).
16.
17. Care of RO Membrane:
Mind fresh everything thing is fresh as like as RO systemmembrane fresh water is
fresh and quality is good. So need to always RO membrane clean and fresh.
Freshness of RO membrane maintain by following work done
1) Primary disinfection with chlorination and Fe2+
to Fe3+
.
2) Iron(Fe3+
) removein Mn sand filter
3) Chlorine remove in ACF
4) Chemicals dosing as per feed water quality.
5) Higher particle removing by MP
6) Secondary disinfection done by UV light.
Sanitation Frequency: Monthly (At High and Low pH)
RO Membrane Performance assured by:
1) Salt rejection %
2) Yield %
3) Pressure difference
18. Water quality parameter after RO Membrane
Water Quality Parameter
SL. NO. Ingredients Name STANDARD LIMIT
AS PER
BDS-1240:2001
STANDARD LIMIT AS
PER
PI
In House
lab test
result
3rd party
lab test
result
01 Colour, Haxen Units,
Max
5 5
02 Odour , Unobjectionable None None
03 Taste Agreeable None None
04 Turbidity NTU, Max 5 1
05 PH Value 6.4-7.4 6-8 5.8-6.1
acidity ------ None None
alkalinity 50 ----- 1-3
06 Total Hardness, ppm 300.00 200 Zero
07 Iron,ppm 0.30 0.1 Nil
08 Arsenic, ppm 0.01 .01
09 Cyanide, ppm 0.01 .01
10 Lead, ppm 0.01 .05
11 Zinc, ppm 3.00 1
12 Mercury, ppm 0.001 0
13 Cadmium, ppm 0.003 .005
14 Calcium, ppm 75.00 ----
15 Chlorides, ppm 250.00 250
16 Fluorides, ppm 1.00 .08
17 Nitrate, ppm 4.50 10(5 for cans)
23 Total Coli form
Bacteria In 100ml
Absent Nil
24 Plate Count In
1ml,Max
1000 0-15
19. Note: All parameter of water tested with facilities of in house laboratory
and this confirm by third party laboratory test such as SGS, BSTI,
BCICR and PepsiCo International approve laboratory.
THANKS
