The document discusses the use of ozone in water treatment processes. It provides background on ozone, including its chemical properties and various methods of generation. The document then outlines several applications of ozone in water treatment, including disinfection, pre-ozonation, oxidation of contaminants like iron and manganese, and removal of hydrogen sulfide. Safety considerations around ozone exposure and methods for detecting leaks are also presented.
Plasma-chemical treatment of industrial wastewaters from brewery “Brasseries ...IJERA Editor
This work focuses on the study of the chemical reactivity of an advanced oxidation process (AOP), called the
plasma technique, in order to prevent industrial effluent from pollution and better cope to several damage of
environment. The oxidizing and acidifying properties of an electric discharge of the gliding arc plasma and its
application to a target which is a real effluent (wastewater from Brasseries du Cameroun -Bafoussam plant)
fascinated this study. Samples were collected from the central collecting point (CCP) of the effluent. The
collected effluent samples were analyzed by volumetric and instrumental methods, and then exposed to the
gliding discharge during specific time periods of 3-60 min to exhibit the desired decontamination effects. At the
end of 60 min of exposure time to the discharge, 52.22% and 50.19% obtained respectively to abatement of
turbidity and rate of fall in absorbance. This reduction can be explained by the fact that the coloured compounds
were degraded and this degradation gave rise to the transparent appearance observed. After stopping the
discharge process, the abatement percentage of BOD5, COD and TOC, were obtained at the same time (60min)
with values of 52.05%, 68.63% and 69.37% respectively. These results reflect the considerable reduction of the
pollution load of the wastewaters collected from CCP of the brewery. These results showed that the
effectiveness of the gliding arc plasma depends not only on the physico-chemical parameters of the target, but
also on the exposure time and concluded that the non-thermal plasma process alone provides good reduction of
organic pollutants in wastewater. Moreover, the phenomenon of post- discharge, even though not studied in
details demonstrated that, after switching the discharge, the evolution of parameters such as pH, electrical
conductivity and TDS increase.
Plasma-chemical treatment of industrial wastewaters from brewery “Brasseries ...IJERA Editor
This work focuses on the study of the chemical reactivity of an advanced oxidation process (AOP), called the
plasma technique, in order to prevent industrial effluent from pollution and better cope to several damage of
environment. The oxidizing and acidifying properties of an electric discharge of the gliding arc plasma and its
application to a target which is a real effluent (wastewater from Brasseries du Cameroun -Bafoussam plant)
fascinated this study. Samples were collected from the central collecting point (CCP) of the effluent. The
collected effluent samples were analyzed by volumetric and instrumental methods, and then exposed to the
gliding discharge during specific time periods of 3-60 min to exhibit the desired decontamination effects. At the
end of 60 min of exposure time to the discharge, 52.22% and 50.19% obtained respectively to abatement of
turbidity and rate of fall in absorbance. This reduction can be explained by the fact that the coloured compounds
were degraded and this degradation gave rise to the transparent appearance observed. After stopping the
discharge process, the abatement percentage of BOD5, COD and TOC, were obtained at the same time (60min)
with values of 52.05%, 68.63% and 69.37% respectively. These results reflect the considerable reduction of the
pollution load of the wastewaters collected from CCP of the brewery. These results showed that the
effectiveness of the gliding arc plasma depends not only on the physico-chemical parameters of the target, but
also on the exposure time and concluded that the non-thermal plasma process alone provides good reduction of
organic pollutants in wastewater. Moreover, the phenomenon of post- discharge, even though not studied in
details demonstrated that, after switching the discharge, the evolution of parameters such as pH, electrical
conductivity and TDS increase.
Plasma-chemical treatment of industrial wastewaters from brewery “Brasseries ...IJERA Editor
This work focuses on the study of the chemical reactivity of an advanced oxidation process (AOP), called the
plasma technique, in order to prevent industrial effluent from pollution and better cope to several damage of
environment. The oxidizing and acidifying properties of an electric discharge of the gliding arc plasma and its
application to a target which is a real effluent (wastewater from Brasseries du Cameroun -Bafoussam plant)
fascinated this study. Samples were collected from the central collecting point (CCP) of the effluent. The
collected effluent samples were analyzed by volumetric and instrumental methods, and then exposed to the
gliding discharge during specific time periods of 3-60 min to exhibit the desired decontamination effects. At the
end of 60 min of exposure time to the discharge, 52.22% and 50.19% obtained respectively to abatement of
turbidity and rate of fall in absorbance. This reduction can be explained by the fact that the coloured compounds
were degraded and this degradation gave rise to the transparent appearance observed. After stopping the
discharge process, the abatement percentage of BOD5, COD and TOC, were obtained at the same time (60min)
with values of 52.05%, 68.63% and 69.37% respectively. These results reflect the considerable reduction of the
pollution load of the wastewaters collected from CCP of the brewery. These results showed that the
effectiveness of the gliding arc plasma depends not only on the physico-chemical parameters of the target, but
also on the exposure time and concluded that the non-thermal plasma process alone provides good reduction of
organic pollutants in wastewater. Moreover, the phenomenon of post- discharge, even though not studied in
details demonstrated that, after switching the discharge, the evolution of parameters such as pH, electrical
conductivity and TDS increase.
Plasma-chemical treatment of industrial wastewaters from brewery “Brasseries ...IJERA Editor
This work focuses on the study of the chemical reactivity of an advanced oxidation process (AOP), called the
plasma technique, in order to prevent industrial effluent from pollution and better cope to several damage of
environment. The oxidizing and acidifying properties of an electric discharge of the gliding arc plasma and its
application to a target which is a real effluent (wastewater from Brasseries du Cameroun -Bafoussam plant)
fascinated this study. Samples were collected from the central collecting point (CCP) of the effluent. The
collected effluent samples were analyzed by volumetric and instrumental methods, and then exposed to the
gliding discharge during specific time periods of 3-60 min to exhibit the desired decontamination effects. At the
end of 60 min of exposure time to the discharge, 52.22% and 50.19% obtained respectively to abatement of
turbidity and rate of fall in absorbance. This reduction can be explained by the fact that the coloured compounds
were degraded and this degradation gave rise to the transparent appearance observed. After stopping the
discharge process, the abatement percentage of BOD5, COD and TOC, were obtained at the same time (60min)
with values of 52.05%, 68.63% and 69.37% respectively. These results reflect the considerable reduction of the
pollution load of the wastewaters collected from CCP of the brewery. These results showed that the
effectiveness of the gliding arc plasma depends not only on the physico-chemical parameters of the target, but
also on the exposure time and concluded that the non-thermal plasma process alone provides good reduction of
organic pollutants in wastewater. Moreover, the phenomenon of post- discharge, even though not studied in
details demonstrated that, after switching the discharge, the evolution of parameters such as pH, electrical
conductivity and TDS increase.
Pressure Swing Adsorption (PSA) is a technology used to separate some gas species from a mixture of gases under pressure according to the species using molecular sieves desiccant.
UV generated ozone systems are primarily used for air applications like
deodorization and disinfection where traces of ozone is suf
fi
cient. Any
application that requires more than trace quantities and concentrations of
ozone will necessarily opt for corona discharge method of generation
Study the effect of using ultrasonic membrane anaerobic system in treating su...eSAT Journals
Abstract
Sugarcane mill produces significant amount of wastes mainly in the form of liquid waste or also knows as sugarcane mill effluent (SCME). SCME can cause water pollution and need proper treatment before it can be discharge into water sources (river or lake). This is due to the high content of Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD), Total Suspended Solid (TSS) and Volatile Suspended Solid (VSS).In present study, biological treatment (anaerobic system) and membrane filtration assisted with ultrasonic effect was carried out to treat the SCME. In anaerobic system, the decomposition of organic and inorganic substrate occurs without the presence of oxygen to treat high concentration of organic carbon waste such as SCME and methane gas (CH4) is produced as a by product in this process. Ultrasonic assisted membrane system is applied in the system in order to enhance the efficiency of the process in treating the SCME. Study was conducted by comparing the quality of the SCME after undergo the treatment process using membrane anaerobic system (MAS) and ultrasonic membrane anaerobic system (UMAS). From the study, it shows that more than 90% (>90%) percents of removal efficiency (BOD, COD, and TSS), and reduce flux decline is achieved by using UMAS
Keywords: Sugarcane waste water effluent, Ultrasonic, Anaerobic Digestion
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Pressure Swing Adsorption (PSA) is a technology used to separate some gas species from a mixture of gases under pressure according to the species using molecular sieves desiccant.
UV generated ozone systems are primarily used for air applications like
deodorization and disinfection where traces of ozone is suf
fi
cient. Any
application that requires more than trace quantities and concentrations of
ozone will necessarily opt for corona discharge method of generation
Study the effect of using ultrasonic membrane anaerobic system in treating su...eSAT Journals
Abstract
Sugarcane mill produces significant amount of wastes mainly in the form of liquid waste or also knows as sugarcane mill effluent (SCME). SCME can cause water pollution and need proper treatment before it can be discharge into water sources (river or lake). This is due to the high content of Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD), Total Suspended Solid (TSS) and Volatile Suspended Solid (VSS).In present study, biological treatment (anaerobic system) and membrane filtration assisted with ultrasonic effect was carried out to treat the SCME. In anaerobic system, the decomposition of organic and inorganic substrate occurs without the presence of oxygen to treat high concentration of organic carbon waste such as SCME and methane gas (CH4) is produced as a by product in this process. Ultrasonic assisted membrane system is applied in the system in order to enhance the efficiency of the process in treating the SCME. Study was conducted by comparing the quality of the SCME after undergo the treatment process using membrane anaerobic system (MAS) and ultrasonic membrane anaerobic system (UMAS). From the study, it shows that more than 90% (>90%) percents of removal efficiency (BOD, COD, and TSS), and reduce flux decline is achieved by using UMAS
Keywords: Sugarcane waste water effluent, Ultrasonic, Anaerobic Digestion
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
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using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
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We have compiled the most important slides from each speaker's presentation. This year’s compilation, available for free, captures the key insights and contributions shared during the DfMAy 2024 conference.
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Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
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2. Ozone in Water Treatment Processes
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https://eg.linkedin.com/in/ahmed-hasham-mmba-01024b27
Chemist / Ahmed Hasham (Hesham) ahmedhasham83@gmail.com
3. About the presenter
Member of the Board scientists Egypt.
Member of Scientific Professions Syndicate.
Member of the Arab Society for experts and Safety Professionals.
Member of the International Association of Engineers.
Expert in water and waste water treatment technologies.
Certified trainer in water treatment field .
Certified trainer in Quality Management Systems field.
https://eg.linkedin.com/in/ahmed-hasham-mmba-01024b27
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4. 3/26/2017
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Contents
1. Introduction
2. Advances in Ozone Generation Techniques
3. The Ozone Contacting System
4. Drinking Water Treatment With Ozone.
5. Pre-ozonation
6. Points of application of ozone in a general water treatment scheme
7. Disinfection
8. Application of Ozone in Water treatment
5. Introduction
So far, ozone has been mainly used in disinfection, in the
inactivation of viruses, decoloration , improvement of taste
and odor of drinking water and in waste-water treatment.
Under today' s conditions, additional treatment steps are
necessary.
Ozonation is introduced in the oxidation of organics ; This
does not involve complete oxidation but yields products
which can be removed by a subsequent treatment step.
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6. However, it has been shown that ozone is capable of doing more.
It is used as an oxidant in controlling biological contamination and in
removing iron, manganese and other heavy metals by precipitation.
The latest findings indicate that preozonation enhances micro-
flocculation and increases the filtration rate of rapid sand filters.
In all cases the application of ozone helps to decrease reliance on
chlorine, which is thought to form by-products harmful to human
health.
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7. Although the commonly used method of ozone
generation by silent electrical discharge has been
known for more than 130 years, there have recently
been some very important advances in this technology
which have made ozonation in water treatment more
efficient and economic.
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8. What is ozone?
It is a molecule comprising of three oxygen atoms
having the chemical symbol O3.
ozone does exist naturally, it is a relatively unstable
and reactive gas.
As well as being a powerful disinfectant.
Today ozone is the strongest commercially available
oxidant.
Most commonly these have been water treatment for
many different industries, and effluent treatment.
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9. Ozone Generation
Electrical energy flowing across a narrow gap that is filled
with oxygen splits the oxygen molecules into oxygen atoms
(O). These atoms combine with other oxygen molecules (O2)
to form ozone (O3).
Specific energy requirement = 0.820 kWh/kg O3
The actual specific energy requirement is much higher (10X
to20X) due to generation inefficiencies
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11. Economics has favored LOX-fed ozone systems since the late 1980s,
when medium-frequency ozone generators, which produce ozone
efficiently at high concentrations, were commercialized.
Oxygen containing feed gas can also be produced using pressure
swing adsorption or vacuum-pressure swing adsorption (also called
vacuum swing adsorption) technology to increase the oxygen
concentration in the feed gas from ambient air levels (21 %vol) to
greater than 90 %vol.
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13. Recognized methods FOR O3 generation
There are four recognized methods:
Corona Discharge
Ultraviolet Radiation
Electrolysis
Radiochemical
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14. Corona Discharge
A high voltage passes through an air gap. In the case of
ozone production, this high voltage transfers energy for
the breaking of the O2 molecule, allowing the formation
of a 3-atom oxygen molecule - ozone. This method is
today the most widely used for commercial ozone
production
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16. Ultraviolet Radiation
the formation of ozone from oxygen is endothermic, that is it requires
energy. When exposed to light an oxygen molecule in a ground state
will absorb the light energy and dissociate to a degree dependent on
the energy and the particular wavelength of the absorbed light. The
oxygen atoms then react with other oxygen molecules to form ozone.
For effective ozone production it is therefore necessary to utilize a short
wavelength ~185nm. In theory, the yield of O3 from 185nm UV light is
130g/kWh of light. As lamp efficiencies are so low, ~1%, the production
per kWh from the power source is greatly reduced.
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18. Electrolysis
Electrolysis is the process in which an electric current
is passed through a liquid, causing a chemical
reaction, resulting in the evolution of gases.
In relation to ozone production, water can be used
as the electrolyte leading to direct diffusion, or
special electrolytes such as H2SO4 can be used and
ozone gas drawn off and diffused and contacted
by the usual methods.
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19. Radiochemical
High energy irradiation of oxygen by radioactive rays
can promote the formation of ozone. Whilst high yields
have been achieved under specific conditions using
oxygen, the best results from an air flow through system
at atmospheric pressure, has been ~ 3-4 mg/m3 . The
process is fraught with complications in filtering harmful
isotopes and it is not viewed with potential use in
commercial applications.
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20. Key Factors affected amount of ozone
The amount of ozone produced together with the efficiency and reliability
of that production are directly related to a number of key factors the main
ones being: -
Feed gas quality.
Power input.
Generation module construction.
Temperature.
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23. Advantage of Ozone application
1. That ozone can be produced from oxygen at higher ozone
concentrations.
2. While consuming low to moderate specific energy (kWh/lbo,).
3. Has lowered operating costs.
4. Also, the number and size of ozone system equipment components
have been reduced, lowering capital and maintenance costs.
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24. Personal Exposure Effects and limits for Ozone
OSHA Permissible Exposure Limit: 8 hour 0.1 ppm
Short Term Exposure Limit 0.3 ppm
light; 0.08 ppm
moderate; 0.05 ppm
2 ppm Immediately Dangerous to Life or Health
5 ppm Respiratory Protection: Use full face self-contained breathing
apparatus for entering areas with high concentration of ozone.
Lethal to small animals within 2 hours 15-20 ppm.
Engineering controls: use ozone destruct units (thermal and/or catalytic) for
off gassing ozone.
Lethal in a few minutes >1,700 ppm.
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26. Leaks detection
These leaks can be located in one of the following three ways and should
be repaired as soon as practical.
Leaks can be located using:
1. A portable ozone detector
2. A weak soap solution sprayed onto the potential leak area (bubbles will
form as the gas escapes)
3. Chemical detection, whereby potassium iodide (2% KI) solution soaked on
a white rag or white paper towel turns a brownish color in the presence of
ozone
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27. Applications in Drinking Water Treatment
All ozone applications involve oxidative reactions, whether ozone is used
for disinfection or oxidation of specific Contaminants.
DISINFECTION TREATMENT
The primary purpose of ozonation at many water treatment plants is to
achieve disinfection log-inactivation credit for viruses, Giardia, and
Cyptosporidium at regulated or above-regulated levels.
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28. The value of 1-log inactivation is the same as 90% inactivation, 2 log is 99%, 3
log is 99.9%) etc.
The term log removal or log inactivation, instead of percent removal, is used in
regulations for ease in disinfection reporting.
Bubble-diffuser contactors that are used for disinfection applications typically have 6, 8,
10, or 12 chambers.
Fewer chambers and shorter detention times (e.g., 6 to 10 min) are commonly used to
meet Giardia and virus disinfection objectives, since required CT values are fairly low.
Extra chambers and additional detention time (e.g., 20 to 60 min) are used for
enhanced disinfection applications.
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30. OZONE OXIDATION TREATMENT
Pre-ozonation
1. Improved particulate removal from filtration, as evidenced by lower
turbidity and lower particle count of the filtered water.
2. Reduced coagulant dosage (e.g., alum or ferric).
Also can used for :
Improved aesthetic quality through elimination of undesirable tastes, odors,
and color.
Oxidized synthetic compounds including pesticides and solvents.
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31. Iron and Manganese Oxidation
Iron and manganese are oxidized easily by ozone.
Soluble ferrous iron Fe(I1) is oxidized to ferric iron (FeIII), which slowly
hydrolyzes to form particulate Fe(OH)3. The reaction consumes 0.43 mg of
ozone per mg of Fe(I1)
Manganese oxidation by ozone and subsequent manganese removal is
quite complex. Ozone oxidizes soluble manganese [Mn(II)] to form
particulate removable) manganese dioxide [MnOz - Mn(IV)]. The reaction
consumes 0.88 mg of ozone per mg of Mn(I1)
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32. Hydrogen Sulfide
Hydrogen sulfide is oxidized easily by ozone to form (ultimately) sulfate.
Oxidation proceeds in stages:
1. first forming insoluble elemental sulfur, which is evidenced by a light-colored
colloidal suspension.
2. Further oxidation dissolves the elemental sulfur, forming soluble sulfite, and
continued oxidation produces sulfate.
3. More ozone is required to completely oxidize sulfide to sulfate than is required to
produce the insoluble, colloidal elemental sulfur.
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33. The theoretical O3 to H2S ratio is 3:l mg/L .
The operating O3 to H2S ratio is 4:1 mg/L.
a. The selected operating ratio is higher so that a moderate ozone residual (0.2
mg/L to 0.3 mg/L in chamber 2) can be maintained.
b. The ozone residual in the downstream chamber is used for process control.
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34. Color Removal
Color in water is removed for at least two reasons:
1. Color is unattractive and is responsible for customer complaints.
2. Color is linked to the presence of fulvic or humic acids, which consume
large amounts of chlorine and form halogenated organics.
Color can be removed sufficiently with coagulation in conventional and
direct filtration water treatment plants, but color is removed very effectively
by ozone oxidation.
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35. Turbidity Removal
Benefits of using Ozone before coagulation / filtration process :
1. Increased filtration rate by 33%.
2. lowered coagulant dose by 50%
3. Reduced filtered water turbidity by 50%
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36. Ozone-based advanced oxidation treatment
Oxidation during ozonation also occurs via hydroxyl
radicals(HO'), which are secondary oxidants that are formed by
ozone decomposition via a complex mechanism.
processes in which 03 is purposefully decomposed into HO') are
important in drinking water treatment because of reactions with
organic molecules such as some solvents
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37. Bromate Formation
Bromate formation and control has been the focus of intensive research
efforts since the early 1990s when bromate (BrO3-) was implicated as a
potential carcinogen.
BrO3- MCL value at 10 µg/L (USEPA, 1998).
Ozone plants can be subdivided into the following three categories, which
relate to their relationship to bromate issues and considerations:
1. Bromide is absent in the source water or is present at low concentration.
2. Bromide is present in the source water at moderate concentration
3. Bromide is present in the source water at a relatively high concentration
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38. 1. Bromide is absent in the source water
Bromide is absent in the source water or is present at low concentration.
Bromate formation is proportional to bromide concentration for given water
quality and ozone dose operating conditions. Low bromide concentration
means low bromate formation potential.
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39. 2. Bromide is present in the source water at moderate
concentration
Bromide is present in the source water at moderate
concentration (e.g., 50 to 100 µg/L), but ozone dose
requirements are such that bromate formation is below the MCL
value of 10 µg/L.
Bromate formation is minimized when:
a. Ozone dose is low as a result of plant operation at low CT value that is still
sufficient to meet the disinfection treatment objective, such as 2-log virus or
0.5-log Giurdia inactivation credit.
b. Ozone dose is low even to meet elevated disinfection requirements (e.g.,
0.5-log Cryptosporidium inactivation credit), because water quality
characteristics are such that the ozone demand is low and ozone decay is
slow (i.e., long ozone half-life).
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40. 3. Bromide is present in the source water at
a relatively high concentration
Bromide is present in the source water at a relatively high
concentration such that bromate formation would exceed
the 10 µg/L MCL value unless bromate mitigation measures
are implemented.
Bromate mitigation options are described here and include
lowering pH, adding ammonia, adding chlorine and
ammonia, or using chlorine dioxide.
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41. References
Kerwin Rakness-Ozone in Drinking Water Treatment_ Process Design,
Operation, and Optimization-American Waterworks Association .
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