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Chlorine (Cl2)
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Sodium hypochlorite (NaOCl)
• Calcium hypochlorite (Ca(OCl)2)
• Chlorine dioxide (ClO2)
• Chloramine
• Ozone,
Non-oxidation type
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Quaternary ammonium
• Glutaraldehyde
• Bisulfide-cyano-methane
Inorganic coagulant Mineral salt
Aluminum sulphate (AlSO4)
• Ferrous sulphate (FeSO4)
• Ferric chloride (FeCl3)
Macromolecular coagulant
Poly aluminum chloride (PAC)
• Polymeric ferric sulfate (PFS)
• Poly aluminum sulfate
Composite inorganic macromolecular coagulant Anion compounds including:
• PAC combining with sulphate (SO42–)
• PFS combining with chloride (Cl–)
• Cation compounds including PAC combining with
ferric ion (Fe3+)
Multi-ion compounds including:
• Complex of ferric ion
• Sulfate radical
• Chloride
Inorganic-organic complex compounds including:
• Complex of PAC and polyacrylamide (PAM)
• Poly chlorinated ferric sulphate
• Poly aluminium silicon
• Poly aluminium phosphorus
• Poly aluminium ferrous
Organic coagulant Synthetic macromolecular coagulant PAM and its ramifications
Natural macromolecular coagulant Amylum, cellulose, mucus of plant, amylose,
protein
and their ramifications
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Water Purification
- Contaminants come from leaking sewage pipelines,
factories discharge, agriculture run-off
- Sources and types of contaminants can be many such as
pesticides, herbicides, hospital waste, industrial effluents, waste land
fills,
heavy metals, microbes and other harmful organic and inorganic compounds.
- Two billion people worldwide do not have access to
clean water.
- Most surface waters are first treated with chemicals
that combine with dirt particles.
- The dirt is then filtered out of the water, making it
clear.
- Then the water is disinfected. In addition treatment is
needed to solve special problems.
- Treatment, as described above, does not remove
dissolved toxic chemicals.
- A chemical disinfectant is added to the drinking water
at the treatment plant.
- Chlorine is the most common disinfectant.
Water Treatment Agents
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The market is divided into sub segments; Coagulants and
Flocculants,
Biocides and Disinfectants,
Defoamers and Defoaming agents,
pH
Adjustors and Neutralizers,
and others.
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Research on Carbon nano filtration membranes and nano
catalysts like iron, silver and titanium dioxide for water treatment
applications is a fast growing field
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According to the Indian government only
30 % of the rural population had access
to safe drinking (tap) water in the country.
55 % depend on tube well or hand
pumps to meet their
drinking water requirement.
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15 % of rural populations were still looking for a
dependable source of water.
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In urban areas, 74 % depend on tap water and 18 % on
tube well and hand
pump
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