5. Water is the life blood of our planet
Sufficient water supply of appropriate quality is a key ingredient
in the health and well-being of humans and ecosystems, and for
social and economic development.
8. Becoming an International Agony
36 percent of the global population—
approximately 2.4 billion people—live in water-
scarce regions
22 percent of the world's GDP (US$9.4
trillion) is produced in water-scarce areas.
39 percent of global grain production is
unsustainable in terms of water
1.4 billion people live in areas with sinking
groundwater levels.
11. Around 17.6% of households in India don't have access to any source of drinking water in or near their
premises.
In last 50 years 21 million wells have been dug and 30% have been abandoned because water no longer
flows.
The main source of drinking is tap water(43.5%) followed by hand pump(42%) and open wells (14.5).
More than 27 million households in India drink untreated water. Around 37.7 million people are affected
by water borne diseases annually.
1.5 million children are estimated to die of diarrhoea alone.
73 million working days are lost due to water borne disease.
Subsequent economic burden is $600 million a year.
66 million Indians are as risk due to excess fluoride, 10 million due to excess arsenic.
13. Multiple Options
The different treatment methods used are classified in three different categories as:
Primary Treatment : Refers to physical unit operations.
Secondary Treatment: Refers to chemical and biological unit processes.
Tertiary Treatment: Referes to combination of all three i.e., physical unit operations
and chemical or biological unit processes, used after secondary treatment.
16. Integration is key
Basics: Coagulation-flocculation followed by sedimentation, filtration and disinfection(chlorine)
17. Economics of different levels of treatments
Particulars Primary treatment
system
Primary + ultra filtration
system
Primary + ultra filtration
system + reverse osmosis
Capital cost (Rs lakhs) 30.0 90.64 145
Annualized capital cost
(@15% p.a. interest &
depreciation
5,79 18.06 26.69
Operation and
maintenance cost
(lakhs/annum)
5.88 7.04 12.63
Annual burden
(Annualized cost +O&M
cost) Rs. Lakhs
11.85 27.1 42.5
Treatment cost Rs./kl
(Without interest and
depreciation)
34.08 52.40 73.22
18. An Inconvenient Truth
• Natural materials have been used in water treatment since ancient times but
lack of knowledge on the exact nature and mechanism by which they work has
hindered their wide spread application.
• As a result, they have been unable to compete with the commonly used
chemicals.
• In recent years there has been a resurgence of interest to use natural
materials due to cost and associated health and environmental concerns of
synthetic organic polymers and inorganic chemicals.
19. Use of Plant Species
• Natural plant extracts have been used for water purification for many centuries and
Egyptians inscription afforded the earliest recorded knowledge of plant materials used for
water treatment, dating back perhaps to 2000BC .
• In recent years there has been considerable interest in the development of usage of
natural coagulants which can be produced extracted from microorganisms, animal or
plant tissues.
• These coagulants should be biodegradable and are presumed to be safe for human health
.
• Natural coagulants produce readily biodegradable and less voluminous sludge that
amounts only 20– 30% that of alum treated counterpart.
• Can reduce hardness in water or wastewater with better performance and a low risk to
environment.
• Nowadays a number of effective coagulants have been identified of plant origin. Some of
the common ones include Moringa olifiera, Solanum incunum, Ocimum sanctum,
Azadirachta indica, Triticum aestivum, Phyllanthus emblica and Strychnos
potatorum and others .
20. Taxonomic diversity of plants used for water treatment.
Family Number of Genera Percentage Number of species Percentage of
species
Fabaceae 10 26.3 10 25.0
Fagaceae 2 5.2 4 10.0
Malvaceae 3 7.8 3 7.5
Cactaceae 2 5.2 2 5
Cucurbitaceae 2 5.2 2 5
Euphorbiaceae 2 5.2 2 5
Poaceae 2 5.2 2 5
Other 15 families 15 39.4 15 37.5
Total 38 100 40 100
21. Who are the eligible candidates?
Ocimum sanctum
Azardiracta indica
Phyllanthus emblicaTriticum aestivum
Solanum incunum
Strychnospotatorum Carica papaya
Moringa oleifera Dolichos lablab Phaselous vulgaris
Opuntia ficus indica
Castanea sativa
24. Many more in the list
Quercus robur Senna alata
Aesculus hyppocast annum
25. Plant parts used
Most of these extracts are derived from the seeds, leaves, pieces of bark or sap,
roots and fruit extracts of trees.
Protein is reported to be the main component responsible for coagulation-flocculation
process.
A polyelectrolyte: active ingredient responsible for coagulation
activity. High cationic charge density, long polymer chains, bridging of
aggregates, and precipitationBioactive constituents:
Pterygospermin (C22H18N2O2S2:),
an unstable substance with low melting point
Benzyl isothiocyanate, Glucosinolate
26. How it works?
The coagulation mechanism was reported to be through
charge neutralization ,adsorption and bridging.
In coagulation and disinfection, a substantial number of active compounds have
been isolated from various parts of plant species. Thus, isolating the active
component is critical not only to understand the coagulation mechanism, but also to
develop pretreatment practices for potential field implementation .
Natural coagulants were more efficient in higher turbidity ranges than lower and
medium turbidity waters either in artificially prepared or natural turbid raw water
including surface and ground water.
27. Of the large number of plant materials that have
been used over the years, Moringa oleifera have
been shown to be one of the most effective crop
species for water treatment
28. Moringa oleifera –Multipurpose tree-Model plant
It has been widely used for many purposes, including water purification by activated carbon from its
seed husks
M. oleifera seeds contain coagulant molecules such as proteins which showed good flocculating effects
.A protein extracted from M. oleifera seed has demonstrated its effectiveness in wastewater systems
removing 99% of suspended solids without changing the pH of the water.
Heavy metal removal such as Cd(II), Cr(III) and Ni(II) .
nutrition sources, medicinal purposes ,antibacterial agents
M. oleifera seed coagulant was able to significantly improve the clarification of highly turbid river
water, showing a high reduction in its turbidity
Protein in the M. oleifera seed is a natural product, which can reduce hardness in water
31. Average seed kernel yield of a mature plant:3 kg
One tree can treat 30,000 ltrs(@ 100 mg/l)
For 1 ha plantation with 3 m spacing yield :3000 kg which
can treat 30,000 m3 water= A treatment plant 10 m 3 hr-1
with 8 hrs a day for a full year
Simple Statistics
Thumbs rule
32. Purification of natural coagulants
• The limitation of natural coagulants and disinfectants include organic load and
residual (storage).
• Therefore, Purification of natural coagulants is vital in order to reduce organic
load and helps to use in a large scale because of the fact that the crude extract is
not generally suitable for large water supply systems where the hydraulic
residence time is very high and this is indicated in the result of who reported
coagulation efficiency decreased as storage duration increased.
• Another disadvantage of natural coagulants is its efficacy only for highly turbid
water.
• Therefore, active agents should be purified and characterized using different
techniques, namely dialysis, ultrafiltration, lyophilisation, ion-exchange,
chemical precipitation, SDS-PAGE and electro phoresis.
• Isolating the active component is critical not only to understand the coagulation
mechanism, but also to develop pretreatment practices for potential field
implementation .
33. • Natural coagulants produce less sludge volume compared with Alum and
they require no pH adjustment..Considerable savings in chemicals and sludge
handling cost may be achieved.
• They are great interest for low or zero net costl water treatment and help to
provide pure water for developing countries who hardly get pure water and an
additional benefit of using coagulants derived from natural products, is that a
number of useful products may be extracted from the seed.
• In particular, edible and other useful oils may be extracted before the
coagulant is fractionated. Residual solids may be used as animal feed and
fertilizer, while the shell of the seed may be activated and used as an
adsorbent.
• Usage of natural products also reduces the formation of disinfectants that
deteriorate human health and their byproducts are organic and biodegradable
and reduced risk of handling.
40. What extra is needed?
• Active agent of indigenous plants which mediates turbidity and microbial removal mechanism that
should be investigated in detail
• Moreover, different simple purifying mechanisms should be investigated in order to reduce organic
load and recontamination. It is particularly important that such trials be applied at small scale
(household) level and scalability of this technology should be investigated.
• For instance they increase organic load in the water which tend restablization to occur.
• In addition water treated with natural coagulants was reported only used for 24 hours and
inefficiency of treating low turbid water (<50 NTU)is another problem.
• However, toxicological test of natural coagulants and disinfectants is also crucial before
implementing the laboratory result to the field.
• In addition, comprehensive cost effectiveness and cost benefit analyses will also be crucial to be
made in order to see the affordability of natural coagulants and disinfectants to the poor community
living in developing countries.
41. Final submission
India is facing daunting challenges in water sector due to the demands of a
rapidly industrializing economy and urbanizing society.
When potential for augmenting supply is limited and water tables are falling,
water quality issues have increasingly come to the fore.
Inventory of indigenous knowledge and plants used by local wisdom for water
purification technologies is an unexplored area with huge unrealized potential.
Plants identified were Moringa oleifera, Jatropha curcas, Pleurotus
tuberregium, Citruss aurontifolia, Strynos potatorium with their potentials as
coagulants with respect to turbidity removal and disinfection of water borne
diseases vis-a vis the pitfalls of chemical coagulants and disinfectants .
Biocoagulants are as efficient as Alum is purifying water and wastewater at
low cost. The need to further develop biocoagulants as green treatment
alternative for global water management admist growing global water crises .
