1. Prof. Kakoli K. Paul
Associate Professor
Department of Civil Engineering
National Institute of Technology
Rourkela, Odisha
Presented by
2. AVAILABILITY OF FRESH WATER
• Out of 70 percent of the earth’s surface water, only three percent is
fresh water
• Only about 0.01 percent of the world’s total water supply is
considered available for human use
• As population grows, requirements for basic personal use rise
proportionately
• Rapid population growth and increasing per capita consumption
squeezed the world’s freshwater resources
3. WASTEWATER PRODUCTION
• With rapid expansion of cities and domestic water supply, quantity
of wastewater is increasing in the same rate as population increase
• Estimated sewage generation is about 70-80 % of total water
supplied for domestic use
• Projected wastewater from urban centers may cross 120,000 MLD
by 2051 and rural India will generate wastewater near about
50,000 MLD
5. PROBLEMS WITH WASTEWATER
• Contains high concentrations of excreted pathogens, potential to
cause disease. Each year millions of people get infected by water
bone disease due to poor water quality
• May lead to environmental problems such as soil sickness, soil and
ground water contamination and phytotoxicity
• Proper investigation is necessary to remove the harmful bacteria
and other micro-organisms from the wastewater before reusing in
agricultural purpose
6. WASTEWATER TREATMENT FACILITY
• Treatment of wastewater requires significant amounts of energy
• Approximately high income countries treat 70% of produced
wastewater, upper middle income countries treat 38%, lower
middle treat 28% and low income treats only 8% of wastewater
• Only 60% of industrial wastewater, mostly large scale industries,
is treated. Remaining 40% goes to the rivers or ponds without
any treatment and pollute the surface water
• Existing treatment capacity is just 21 per cent of the present
sewage generation, remaining untreated sewage is the main cause
of pollution of rivers and lakes
7.
8. Wastewater Treatment By Vermifiltration
Fig. 1 Internal process and body parts of earthworm [Source: K. Samal, R. R. Dash, and P.
Bhunia, “A comparative study of macrophytes influence on performance of hybrid
vermifilter for dairy wastewater treatment,” J. Environ. Chem. Eng., vol. 6, no. 4, pp. 4714–
4726, Aug. 2018.
11. Vermifiltration is an eco-friendly sustainable low cost technology
for the treatment of wastewater. Vermifiltration in inclusion of
hydroponic macrophytes for removal of various pollutants from
wastewater can be added low cost mitigation measure.
Earthworm acts as the extraordinary waste and environmental
administrator. Many investigators have found that earthworm
efficiently biodegrade or bio accumulate organic and inorganic
chemicals such as heavy metals, pesticide, micro pollutants in the
medium in which it colonize.
13. Advantages of Vermicompost
1) Accelerates Germination: Seeds sprout more quickly and
healthier.
2) Increases number of fruits: More numbers of fruit yields
3) Accelerates flowering: Quick flowering takes place
4) Production of humic acids: Vermicompost helps to create humic
acids and plant growth hormones It is major contributor to
disease resistance and pest deferrence
5) Nutrients released slowly: As required, nutrients release slowly
14. In any biological treatment system, DO have a crucial role in
treatment process. In vermifiltration system, DO of wastewater can
slows down/speeds up the rate of each and every mechanism
associated inside the system. Earthworms perform ingestion to add
more DO to the treatment unit. Optimum DO present in the system
works with aseptic conditions in entire bed and nullify the
probability of growing dead pockets in filter bed. Reduction of dead
pockets strengthens the treatment system by enhancing removal
efficiency.
15. Initially, DO is lower in vermifilter and in later stage it increases until
a steady state is achieved. Variation of DO is due to organic matters
and nutrients that are already present in vermifilter. Earthworm
contributes DO to the system and increases the treatment efficiency.
The DO depends on hydraulic loading, practice of feeding, earthworm
density and species of earthworm. The DO concentration is more in
vertical flow vermifilter as compared to horizontal flow vermifilter.
16. Organic loading plays an important role by verifying the DO presence
in the effluents obtained from vermifilter. In high temperature
earthworm increases the activity of metabolism and respiratory and
consumes high DO. Biological reaction, diffusivity of air of the bed
material, and biodegradation of organic pollutant of effluent also
affects the temperature of system. Optimal temperature required for
vermifiltration ranges from 26-370 C.
17. Earthworm presents in the vermifilter buffer their own temperature
by themselves. The exothermic reaction performed by earthworm
increases the temperature. The rise of temperature in vermin system
is due to the heat generated from the oxidation of organics. The
water which are supplied constantly help to push to a certain
temperature for suitable application of microbes.
18. Pyrolysis, incineration, land filling, shredding, composting,
pulverization etc are commonly practiced for biomass management.
But for macrophyte biomass management still vermicomposting is a
sustainable method as it requires minimum or zero energy with non-
hazardous ecofriendly byproduct. Vermifiltration produces
comparatively less amount of sludge. Vermifilter bed trap all the
solids present in wastewater by digestion. Earthworm cast (excreta)
are mainly composed of soil and gets converted into carbon dioxide
and water during decomposition.
19. In case of integrated macrophyte vermifilter, the top surface of the
treatment system is covered with macrophyte leaves which help
earthworm as they are sensitive to sunlight and rain. The
macrophyte root tips and young laterals release oxygen by creating a
oxidized protective layer on the tissues of the root surface. In
macrophyte filter system during clogging also earthworm help to
restore its efficiency and the operation for a long term. The
processes which contribute for the clogging of the system are large
amount of sludge production, chemical precipitation, plants root
growth, suspended solid accumulated, gas generation.
20. To control clogging in the integrated macrophyte filter the
earthworm plays vital role. The root system of macrophyte provide
a large surface area for various bacteria like autotrophs,
heterotrophs, nitrifiers. The macrophyte root system and gut of
earthworm increases the diversity of microbes in the filter bed.
Usually the removal of phosphorus is done by adsorption and
through uptake by plant. The fungus and plant in the filter develop a
symbiotic relation in which macrophyte (plant) provide carbon and
in return get phosphorus and minerals from fungus. The pH of the
filter system is controlled by earthworm. Also algae present in the
system uptake phosphorus in form of orthophosphate.
21. Macrophyte or hydroponic planting add oxygen to the system and
help in uniformly distribution of microorganisms. Also, they absorb
the organics through their root system. Macrophyte integrated
system help in maintaining porosity in top and bottom zone of the
filter. Literature study found still vermifiltration has some
limitations. Present research need to focus to counteract the
limitations for efficient removal of pollutants. Hence, in order to
make this treatment system as an eco-friendly, efficient, and
sustainable process more investigation should be done on
optimization of design and operating parameters and integrating
with appropriate plant-earthworm species.
23. Emerging pollutants are chemicals and compounds that have
recently been identified as dangerous to the environment, and to
the health of human beings. “Emerging” may be because of the
rising level of concern.
24. Emerging pollutants even in trace amount can cause adverse
health effects
Emerging Contaminants are consistently being found in
groundwater, surface water, municipal wastewater, drinking
water and food sources.
25. Emerging pollutants include a variety of compounds such as
antibiotics, drugs, steroids, endocrine disruptors, hormones,
industrial additives, chemicals, and also microbeads and
microplastics. There is a link between these pollutants and
wastewater. Municipal, industrial, and domestic wastewater
are, in fact, a primary pathway for their wide diffusion in
the aquatic environment. They include pharmaceuticals,
personal care products, pesticides, herbicides and endocrine
disrupting compounds
26. Emerging contaminants are synthetic or naturally occurring
chemicals or any microorganisms that are not commonly
monitored in the environment but have the potential to enter
the environment and cause known or suspected adverse
ecological and/or human health effects. They may be
perfluorinated compounds, water disinfection byproducts,
gasoline additives, manufactured nanomaterials, human and
veterinary pharmaceuticals, etc.
27. Following are conventional pollutants: biochemical oxygen
demand (BOD5), total suspended solids (TSS), fecal
coliform, pH, etc. Chemicals of emerging concern can
include nanoparticles, pharmaceuticals, personal care
products, estrogen-like compounds, flame retardants,
detergents, and some industrial chemicals with potential
significant impact on human health and aquatic life
28. MORINGA OLEIFERA IN WASTEWATER TREATMENT: A CASE
STUDY (Study performed by MTech-R)
• Hard to afford the costs of imported chemicals for water and wastewater
treatment
• Moringa Oleifera (MO) can be non-toxic and hence recommended for its use
as a coagulant in developing countries
• Added advantage over the chemical treatment of water because it is
biological and reported as edible and can be used in the rural areas where no
other facility is available for the wastewater treatment.
29. • It was found that MO is most widely used plant for the removal of
pathogens, physicochemical and heavy metals from the wastewater
• Use of several natural plants in wastewater (i. e. phytoremediation)
is sometimes costly, it needs large setup as well as availability of
aquatic plants is not so easy as compared to MO
30. Methodology
Moringa Oleifera seeds purchased from local market were grounded
using grinder
50 mg of MO seed powder was added in 1 liter of treated municipal
wastewater and it was stirred at 150 rpm for 45 min. The stirred
sample was allowed to settle for 20 minutes
31. • To know about the surface topography, composition and phase
identification, SEM and XRD analysis of MO seed powder
were performed
• To study the changes in the parameters of sample, physico-
chemical analysis of treated municipal wastewater with MO
seed powder was performed
• For the optimization of MO seed powder in the dissolution
process, DOE (design of experiments) and to know about the
dissolution mechanism, several kinetic models were applied
32. ANALYSIS OF MORINGA OLEIFERA SEED POWDER
SEM analysis of Moringa Oleifera seed powder
• Particle size of MO seed powder was not uniform
• Some particles were big and others were small sized having fibrous
structure with honeycomb like pores or cavities on them
• Potassium (K), carbon (C), calcium (Ca) and oxygen (O) found in
magnificence amount through EDS analysis
33. XRD analysis
• Potassium (K) (438 cts.) detected in higher concentration from
XRD analysis as compared to oxygen and carbon compounds
• Indicates the amorphous structure of MO seed powder
• It contains significant amount of potassium
• After the addition of MO seed powder in treated municipal
wastewater effluent its physicochemical characterization were
again performed.
34. OPTIMIZATION OF MO SEED POWDER
Design of experiment (DOE) for dissolution of potassium
• Based on combination of the four process parameters (i.e., pH,
temperature, time and dose of solute) DOE was performed
• Levels of the studied process parameters (A, B, C and D
refers the coded value of pH, temperature, time and dose of
solute respectively) affecting dissolution process of potassium
employed in the experiment taken as 2
35. DISSOLUTION KINETIC MODELS
• To study the release mechanism of solute in the solution form
mathematical models are necessary
• From the main and interaction effect plot it was found that for the
best optimization process desirable values are
pH = 7.5
Time = 67.50 min
Dose of solute = 52.50 mg /l
Temperature = 47ºC
• Zero order, first order and shrinking core models has been used for the
dissolution kinetic modeling
36. • Study found that the dissolution kinetics of potassium can be
described by the Shrinking Core Model with diffusion control
process because it gives the best fit of curve of having highest R2
value (0.977) among all other models.
• Regression coefficients of dissolution kinetics for different models
Models Temperature
17º C 27º C 37ºC 47ºC
Zero order 0.924 0.894 0.765 0.581
First order 0.963 0.894 0.765 0.560
Higuchi 0.961 0.923 0.806 0.580
Chemical reaction control
shrinking core
0.930 0.950 0.943 0.848
Diffusion reaction control 0.939 0.977 0.960 0.819
37. • In the dissolution experiments, the dissolution reaction is
extremely dependent on temperature
• According to the highest regression coefficient (0.977), best
desirable temperature for the dissolution process of potassium as
per the shrinking core model is 27° C
• Dissolution process is temperature dependent, indicates the
mechanism of dissolution of potassium follows diffusion through
a semi-permeable product layer
• Highest dissolution rates were obtained at high temperature
38. • With the increase in temperature, equilibrium or saturation point of the
dissolution process achieved at early time period
• At 17° C, 27 ° C and 37° C equilibrium state of dissolution process occurs after
90 minutes
• At 47° C, after 70 minutes of dissolution process equilibrium point of potassium
dissolution in treated municipal wastewater occur
• With the increased in temperature active site of the solute increases hence it
dissolve more potassium in the early time stage
• Surface of the particle creates active sites until a reaction front is
established, and through which the ions of the medium and the potassium from
MO seed powder start to diffuse
• This is followed by a progressive conversion period, when the concentrations of
potassium progressively increase until reaching stabilization indicating the end
of the reaction.
