This document discusses techniques for defluoridation or removing excess fluoride from drinking water. It begins by explaining the health risks of both inadequate and excessive fluoride intake. The main techniques discussed are adsorption using materials like activated alumina or bone char, ion exchange using resins, precipitation using chemicals like those in the Nalgonda technique, and other methods like reverse osmosis or electrolysis. The Nalgonda technique, which involves adding alum, lime and bleach to precipitate fluoride, is highlighted as being effective, simple and economical for community water supplies in India. Maintenance and modifications to the techniques are also reviewed.
Minimally invasive dentistry (MID) is an evidence based intervention approach supported internationally that aims to do the least harm to effected and surrounding tissues
Minimally invasive dentistry (MID) is an evidence based intervention approach supported internationally that aims to do the least harm to effected and surrounding tissues
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.
Fluoride is often called as sword as an expression for anything that can simultaneously help & hinder .
Accumulated evidence from numerous studies show that the prolonged use of fluoride at recommended levels doesn't produce harmful physiological effects in human.
Inadequate ingestion of fluoride is associated with dental caries & an extensive intake of fluoride can lead to dental & skeletal fluorosis
Acute ingestion of fluoride in large quantities may be followed by rapidly developing signs and symptoms which may result in death
This powerpoint covers all important topics regarding WATER.
Purification ,storage, chlorination and many more ....
For any queries contact @Deepacasm
E-mail :- Delphicneupane@gmail.com
PIT AND FISSURE SEALANTS- PUBLIC HEALTH DENTISTRYANKUSHA ARORA
Introduction
Definition
Morphology of Pits and fissures
Types of Pit and fissure sealants
Materials used as sealants
Requirements of sealants
Diagnosis of Pit and Fissure caries
Procedure of application of sealants
Indications
Contra-indications
Factors affecting sealant retention in mouth
Summary
Fluoride has been an long going issue and there are still researches undergone for its mitigation.Some of the useful technologies that can be applied which are both cost and time effective.These are been carried out for reduction in the fluoride content in ground water and also to provide an better drinking water quality.
Fluoride is a typical component of natural waters and its concentration varies depending on the water resource. Water may be contaminated by natural sources like more alkaline ions (CO32-+HCO3->10.4 meq/l water) reacts with halite which comes from industrial effluents. This is ensuing in fluoride concentrations up to 12.7 mg F–/l where ground level of water is low. WHO standards and BIS: 105000, 1991 permit only 0.5-1.5 mg/dl as the upper permissible limit for fluoride in drinking water for the Indian context. Fluoride in excess of the permissible limits in drinking water causes a number of endemic conditions referred to collectively as “fluorosis”. This paper explores the sorptive answer of a recently developed adsorbent, Activated alumina finely grinded with coconut shell powder. The efficiency of the sorption of fluoride ion is affected by pH, contact time, adsorbent dose, type and size of adsorbents. The adsorption equilibrium is well correlated by Freundlich and Langmuir models
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.
Fluoride is often called as sword as an expression for anything that can simultaneously help & hinder .
Accumulated evidence from numerous studies show that the prolonged use of fluoride at recommended levels doesn't produce harmful physiological effects in human.
Inadequate ingestion of fluoride is associated with dental caries & an extensive intake of fluoride can lead to dental & skeletal fluorosis
Acute ingestion of fluoride in large quantities may be followed by rapidly developing signs and symptoms which may result in death
This powerpoint covers all important topics regarding WATER.
Purification ,storage, chlorination and many more ....
For any queries contact @Deepacasm
E-mail :- Delphicneupane@gmail.com
PIT AND FISSURE SEALANTS- PUBLIC HEALTH DENTISTRYANKUSHA ARORA
Introduction
Definition
Morphology of Pits and fissures
Types of Pit and fissure sealants
Materials used as sealants
Requirements of sealants
Diagnosis of Pit and Fissure caries
Procedure of application of sealants
Indications
Contra-indications
Factors affecting sealant retention in mouth
Summary
Fluoride has been an long going issue and there are still researches undergone for its mitigation.Some of the useful technologies that can be applied which are both cost and time effective.These are been carried out for reduction in the fluoride content in ground water and also to provide an better drinking water quality.
Fluoride is a typical component of natural waters and its concentration varies depending on the water resource. Water may be contaminated by natural sources like more alkaline ions (CO32-+HCO3->10.4 meq/l water) reacts with halite which comes from industrial effluents. This is ensuing in fluoride concentrations up to 12.7 mg F–/l where ground level of water is low. WHO standards and BIS: 105000, 1991 permit only 0.5-1.5 mg/dl as the upper permissible limit for fluoride in drinking water for the Indian context. Fluoride in excess of the permissible limits in drinking water causes a number of endemic conditions referred to collectively as “fluorosis”. This paper explores the sorptive answer of a recently developed adsorbent, Activated alumina finely grinded with coconut shell powder. The efficiency of the sorption of fluoride ion is affected by pH, contact time, adsorbent dose, type and size of adsorbents. The adsorption equilibrium is well correlated by Freundlich and Langmuir models
While trace amounts of fluorine are essential for life, its excessive intake
leads to a disease known as fluorosis. It is a predominant ailment in majority of the
countries inclusive of India. It is caused also by drinking fluoride containing water.
Retention of fluorine in bones and teeth occurs through F−–(OH−) exchange on their
inorganic component known as hydroxylapatite. Endeavour of the present study is to
design a column using activated alumina as an adsorbent for continuous defluoridation
ofwater for domestic purpose. As a part of it, operational defluoridation capacity
of aluminawas determined by variation of different factors (amount of alumina, time,
temperature, added salts). A family of four members was taken as a model. The initial
and final fluoride concentrations were taken as 2.0 and 0.7 ppm, respectively.
Dimension of the unit (adsorbent bed diameter and height) was determined.
Defluoridation of Ground Water Using Corn Cobs Powdertheijes
Most of the adsorbent used for removal of fluoride from drinking water is activated carbons. It is an expensive material, and so the use of alternative, which is a cheaper adsorbent, is required. Hence in the present work, an attempt has been made to remove the fluoride in drinking water using corn cobs powder as a natural adsorbent using a fabricated filter. The Bureau of Indian Standard has recommended the limit of fluoride content of 1mg/l (BIS: 10500-2012). The water samples were collected in different places namely Uppinahally, Doddagatta and Yadapura in Arsikere taluk of Hassan district. The defluoridation is done with corn cobs powder and then the results were compared. Filtration with corn cobs powder reduces the fluoride content for the samples from Uppinahally, Doddagatta and Yadapura with initial fluoride content 2.5mg/l, 1.2mg/l, and 1.4mg/l respectively to 1.01mg/l, 0.9mg/l and 0.8mg/l respectively
Water treatment is any process that improves the quality of water to make it appropriate for a specific end-use. The end use may be drinking, industrial water supply, irrigation, river flow maintenance, water recreation or many other uses, including being safely returned to the environment. Water treatment removes contaminants and undesirable components, or reduces their concentration so that the water becomes fit for its desired end-use. This treatment is crucial to human health and allows humans to benefit from both drinking and irrigation use.
Nano-adsorbent for fluoride removal from drinking waterPranjalSaheb
Fluoride occurs naturally in most water supplies.
Main sources of fluoride in groundwater-
The weathering and leaching of fluorinated minerals.
Industrial wastewater discharges .
With increased human industrial activities, high fluoride-content water has become a widespread problem in the world.
WHO has given a guideline limitation of less than 1.5 mg/L of fluoride in drinking water.
Various industries such as glass and ceramic production, fertilizer and semiconductor manufacturing contribute to fluoride pollution to a large extent. The effluents of these industries may reach to thousands of mg per L, which is higher than natural water.Depending on the concentration and water temperature, the effect of fluoride in drinking water can be beneficial or harmful to mankind. The presence of small quantities of fluoride in ingested water is often considered to have a beneficial effect on human health and helps in the normal mineralization of bones and dental formation.
On the contrary, excessive intake of fluoride leads to osteoporosis, Alzheimers syndrome, skeletal fluorosis, dental fluorosis, cancer, infertility, and thyroid disorder.
Removal of fluoride from synthetic waste water by using “bio adsorbents”eSAT Publishing House
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
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
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Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
2. Introduction
Fluoride is often described as a „double-edged sword‟
As inadequate ingestion is associated with dental caries.
Where as excessive intake leads to dental, skeletal and soft
tissue fluorosis- which has no cure.
3. The 1984 WHO guidelines suggested that in areas with a
warm climate the optimal fluoride concentration in
drinking water should remain below 1 mg/l (1ppm or part
per million), while in cooler climates it could go up to 1.2
mg/l.
Optimum fluoride concentration in drinking water may be
defined as “the one that can arrest the prevalence of
dental caries sans causing a insignificant amount of
fluorosis”
4. The concentration of fluoride in water is directly
proportional to the degree of fluorosis.
Enamel mottling is widespread in area with water having
fluoride content of 3 ppm.
Mottling with discrete pitting of enamel was noticed at
fluoride levels of 4 ppm.
Mottling is less in case of fluoride levels of 2.5 ppm to 3
ppm with a dull, chalky, white appearance of teeth.
No motteling or any enamel changes where observed in area
with water containing 1 ppm fluoride.
5. Fluoride level in geographical areas
The total number of people affected is not known, but a
conservative estimate by UNICEF would number in the
tens of millions
The highest fluoride concentration ever found in natural
water was 2800 mg/l, recorded in Lake Nakuru in the Rift
valley in Kenya
15 of India's 32 states and union territories were
identified by UNICEF as endemic for fluorosis
6. The main fluoride bearing areas are Gujrat,Rajasthan,Andrha
Pradesh where about 50 to 100% of districts are affected.
7. Methods of defluoridation
Providing water, with optimal fluoride concentration is
the only way by which the generation yet to be born can
be totally protected against the disease
It can be achieved by the following methods:
Removal of fluoride from water (defluoridation), using
suitable techniques.
Locating alternative sources of safe water.
Bringing in water from a distant, safe source.
8. Defluoridation Techniques.
Defluoridation was the conventional and widely tested method
for supplying safe water to the fluorosis affected communities.
Defluoridation is defined as, „the downward adjustment of
level of fluoride in drinking water to the optimal level‟
Defluoridation techniques can be broadly classified in to four
categories:
Adsorption technique
Ion-exchange technique
Precipitation technique
Other techniques, which include electro chemical
defluoridation and Reverse Osmosis.
9. Adsorption technique of defluoridation
This technique functions on the adsorption of fluoride ions onto
the surface of an active agent.
Activated alumina, activated carbon and bone char were
among the highly tested adsorbing agents.
Activated Alumina
Application of domestic defluoridation plant, based on
activated alumina, was launched by UNICEF in rural India
The disadvantages with activated alumina are; Adsorption of
fluoride is possible only at specific pH range, needing pre-
and post- pH adjustment of water.
Frequent activation of Alumina is needed, which make the
technique expensive.
10. Bone char
the process of Defluoridation by bone char as the ion
exchange and adsorption between fluoride in the
solution.
The efficacy of the plant depends upon temperature
and pH of raw water; duration for which the bone-char
is in contact with raw water.
It is a highly economic technique with a defluoridation
percentage of 62 to 66
11. Disadvantage :
The bone char harbors bacteria and hence
unhygienic.
It is a technique sensitive procedure,
he use of bone-char may invite cultural and religious
objections
12. Brick pieces column
The basic principle of functioning of Brick piece column is
the same as that of activated alumina.
The soil used for brick manufacturing contains Aluminium
oxide.
Mud pot
The fluoride removal capacity will vary with respect to
the alumina content
The major advantages of mud pots are they are economic
and readily acceptable for the rural communities .
13. Natural adsorbents
Many natural adsorbents from various trees were tried
as defluoridation agents.
Seeds of the Drumstick tree, roots of Vetiver grass and
Tamarind seeds were few among them.
Researchers at “M. S. Swaminathan Research
Foundation‟ (MSSRF) had shown drumstick seeds to
have remarkable defluoridation efficiency, which was
higher than that of activated alumina.
14. Defluoridation by Ion-Exchange
technique
Synthetic chemicals, namely, anion and cation exchange
resins have been used for fluoride removal.
These are commercially produced resins which are expensive
and uneconomical in most circumstances
a) Carbion :it is a cation exchange resin of good durability and can be
used on sodium and hydrogen cycle.
15. b) defluoron 1:a sulphonated saw dust impregnated with 2% alum
solution.
c) Defluoron 2: this was developed in 1968 to over come the
problem of defluoron 1. it is a sulphonated coal using aluminium
solution at regenerant.
16. Defluoridation by Precipitation
technique
The two major drawbacks of Ion-exchange and
adsorption techniques are:
The necessary flow through system is often difficult
to arrange where there is no piped water supply
gradual exhaustion of the active agent is not easily
detected.
17. Precipitation methods are based on the addition of
chemicals (coagulants and coagulant aids) and the
subsequent precipitation of a sparingly soluble fluoride
salt as insoluble fluorapatite
The best example for this technique is the famous
Nalgonda technique of defluoridation.
18. Nalgonda technique
National Environmental Engineering Research Institute
(NEERI), Nagpur has evolved an economical and simple
method for removal of fluoride which is referred to as
„Nalgonda Technique‟ (Nawlakhe et al 1974).
The process comprises addition in sequence of sodium
aluminate (filter alum), lime and bleaching powder to the
fluoride water followed by flocculation, sedimentation and
filtration.
This technique is extremely useful for both domestic as
well as for community water supply.
19.
20. Mechanism
The unit holds 22 litres of water, which is filled into the
upper chamber.
Rapid mix:
Rapid mixing is an operation by which the coagulant is
rapidly and uniformly dispersed through out a single or
multiple phase system.
It is rapidly mixed for a period of 30 to 60 sec with speed of
10 to 20 rpm so that the coagulant is rapidly and uniformly
dispersed.
This help in the formation of micro flocs and result in proper
utilization of chemical coagulant.
21. Flocculation :
It is the 2nd stage of the formation of suitable
particles(flocs) from destabilized colloidal size
particles.
It is achieved by gentle and prolonged mixing for a
period of 10 to 15 min with the speed of 2 to 4 rpm.
22. Sedimentation :
It is the separation from the water by gravitational
setting of suspended particles that are heavier than
water.
Factors that affect sedimentation are:
a) Size,shape,density and nature of particles
b) Viscosity,density and temperature of water.
c) Surface over flow rate.
d) Velocity of flow.
e) Effective depth of settling zone.
23. Filtration:
It is the process of separating suspended and colloidal
impurities from water by passes through a porous
media.
The flocculated water is allowed to settle and filter
through fullers earth candle overnight.
Treated water will be available for drinking and
cooking with desire level of fluoride.
24. Maintenance of Nalgonda filters
The package plant installed on hand pump scheme costing
Rs 1.6 lakh to serve 250 population.
To serve population of 250, 50 stainless steel filters are
required and the cost of 50 filters is approx. Rs 35000.
The main advantage will be its low cost of investment and
low cost of maintainence.
25. Advantages of Nalgonda technique
Regeneration of media is not required.
No handling of caustic acids and alkalies.
The chemicals required are readily available and are used
in conventional municipal water treatment.
Adaptable to domestic use.
Economical
Simplicity of design ,construction,operation and
maintainence.
26. Can be used to treat water in large quantities for community
usage.
Highly efficient removal of fluorides from high levels to
desirable levels.
Little wastage of water and least disposal problem.
Needs mimimum of mechanical and electrical equipment.
No energy except muscles power for domestic equipment.
Local semi-skilled workers can be readily employed.
Simplicity of design, construction, operation and
maintenance.
27. Simultaneous removal of color, odor, turbidity, bacteria
and organic contaminants.
Normally, associated alkalinity ensures fluoride removal
efficiency.
Provides de-fluoridated water of uniform acceptable
quality.
28. Disadvantages of Nalgonda technique
Desalination may be necessary when the total dissolved
solids exceed 1500 mg/l.
Hardness of the raw water in the range of 200 mg/l to 600
mg/l requires precipitation softening and beyond 600 mg/l
becomes a cause for rejection or adoption of desalination.
Generation of higher quantity of sludge compared to
electrochemical defluoridation
29. The large amount of alum needed to remove fluoride.
Careful pH control of treated water is required.
High residual aluminium is reported in treated water by
some authors.
30. Indications of Nalgonda technique
Absence of acceptable, alternate low fluoride source
within transportable distance.
Total dissolved solids below 1500 mg/l.
Total hardness is below 600 mg/l.
Raw water fluorides ranging from 1.5 - 20 mgF/l.
31. Modifications for Nalgonda technique.
Poly Aluminium Chloride:
It is evident that for higher concentrations of fluoride,
the removal efficiency of fluoride is higher with Poly
Aluminium Chloride (PAC) when compared with Alum.
Poly Aluminium Hydroxy Sulphate(PAHS):
A polymeric aluminum compound, poly-aluminium-
hydroxy-sulphate(PAHS) is found to require less
flocculation time and settling time.
32. Other techniques of defluoridation
Reverse osmosis, electrolysis and electro dialysis are
physical methods that are tested for defluoridation of
water.
Though they are effective in removing fluoride salts from
water, there are certain disadvantages that limit their
usage on a large scale.
33. Reverse Osmosis and Electro dialysis:
In reverse osmosis, the hydraulic pressure is exerted on
one side of the semi permeable membrane which forces
the water across the membrane leaving the salts behind.
In electro dialysis, the membranes allow the ions to pass
but not the water. The driving force is an electric current
which carries the ions through the membranes
Electro dialysis is highly energy intensive and expensive.
Both processes are very complicated
34. Defluoridation by electrolysis:
The basic principle of the process is the adsorption of
fluoride with freshly precipitated aluminum hydroxide,
which is generated by the anodic dissolution of
aluminum or its alloys in an electro chemical cell.
Advantages :
Does not require addition of chemicals.
No need to pre & post-treatments .
Low volume of sludge.
35. Units can be designed for any capacity.
Units are designed for specific locations & fluoride content of
water. But can be operated with varying fluoride
concentrations by slightly altering the operating parameters.
The electrochemical reactor occupies less floor space.
Operator friendly
Requires less electric energy (0.3 to 0.6kwh/1000 lts)
36. Conclusion:
Fluorosis is an important public health problem in India.
Drinking water is the main source of ingestion of fluoride.
There is no cure to the disease and prevention is the only
solution.
Nalgonda technique is the most suitable technique for
Indian rural communities.
37. Communities should be educated and encouraged to
actively participate in the procedure.
Suitable technique for the community should be
identified.
Priority should be given to techniques, which utilize
locally available materials as defluoridation agents.