Kind: captions
Language: en
session i also want to greet all of you
who are currently watching this webinar
via youtube live stream and i hope you
can enjoy this webinar session and can
get a lot of new insight
before we start it is highly recommended
that you subscribe to the psl
interview channel and click on the bell
next to it so you don't miss out
any information about our other webinars
even in the previous discussion we
discussed a lot about this
characteristic of wastewater
the principle of selecting technology
and planning for wastewater facilities
now we will discuss of one of the
specific wastewater treatment
technologies
we call it aerobic biological treatment
processes
more specifically we will discuss in
sufficient details
about one of biological wastewater
mechanics namely
membrane aerated biofilm reactors or we
usually call it mbr generally if we talk
about aerobic treatment we know a lot
about
and even designing our wastewater
treatment facilities using activator
slides right
but to use it active and slots require
an additional unit
namely the clarifier or etc to separate
the solid
however what if we can get both
of this functionality in just one unit
to find out more about these things we
will discuss it furthermore
in this session which we titled
conventional
activator sludge to membrane edited by a
film directors
scope application and challenges
without wait any longer we will be
thought by a professor from the asian
institute of technology
who has published more than 150
international journal papers
more than 20 years of experiences
teaching environmental engineering and
management related courses
at graduate level at ashen institute of
technology
he also has interest in researching on
membrane technologies for water and
wastewater treatment
by focusing on development mbr systems
water recycling and
industrial waste water treatment and
also cleaner production and salt waste
disposal and management
so immediately with all the following
experience we hope to get
interesting scientific knowledge and
discussion with all of us in this
discussion
and in this session with professor fish
fanathan
and prof you may start your session
right
okay now you yeah bye
okay thank you very much good morning
chandra
and good morning okay i'm bishop
let me take the next 50 minutes
to give a short presentation on
conventional activate slides to membrane
aerated bioflame
reactors thanks a lot for the nice and
very crispy introduction let me move
into my slides
okay you can see my slides uh yes
good morning i'm going to talk to you
about
conventional activate sludge to membrane
aerated
biofilm reactors i think most of you
know
what is conventional activate sludge and
most of you know
what is membrane bioreactors so i'm
going to talk to you
the bridging gap between these two how
membrane bioreactors move to the next
level
what we call membrane aerated biofilm
reactors
okay if you look at the current
scenario okay huge amount of
domestic wastewater is produced okay
it's come from household industries
agriculture
hospital and recreational activities etc
etc
wastewater treatment has become
essential for removal of pollutants okay
we need to remove them before we
discharge into waterways
to a large extent in the past we focus
on removing
organics that is what a conventional
activate sludge process will do
it will remove the organics but still
leaves
the nutrients or the nitrogen and
phosphate
in the water so we discharge waste water
removing organics but still
containing nitrate and phosphate that
creates
the sufficient amount of environmental
degradation
but because of that in the last
10 years national governments of
emphasize
in asia pacific region to remove these
nutrients
so the wastewater treatment plants need
to be changed
or need to be modified to remove nitrate
and phosphate
i think this you know very classic
typical
acute sludge process preliminary
treatment primary sedimentation
aeration tank sedimentation then you
have
depending on the discharge point you
need chlorinate and discharge
and you can see to a large extent
in this process we will have suspended
growth of microorganism so the organics
gets trapped in between
okay it could be physically trapped or
biochemically convert into carbon
dioxide
and water by microorganisms and the
growth and this
microorganisms are removed as slides and
you get the treated water
so in this process uh the microorganisms
to survive we need to use
huge amount of electricity okay
and you need to supply air
only a small percentage less than 30
percent
of the air v supply it's consumed by
these microorganisms
so there's a huge inefficiency how we
provide air inactivates that process
okay and it's also very important on
this process
it's basically the organic is removed
the nitrate and phosphate is removed
only a small fraction
it is converted by microorganisms to
growth
but otherwise a huge amount of nitrate
and phosphate
remains and this last you will see
travel around the region you will find
huge
wastewater treatment plants like you can
see that aeration tank
sedimentation tanks in china or u.s
and this is what you will find a huge
activate slice treatment plant works
very well
okay but doesn't remove all pollutants
but
mainly removes the organic pollutants
and it's also a huge cost
of operational cost in terms of
power consumption to overcome this
problem
and the last 10 15 years
we are moving into a membrane bioreactor
i will not explain that
too much but the membrane bioreactor
essentially consists of
if you look at it you have an aeration
type
and you have a sedimentation tank you
can see the amount of surface area in
use
we could bring them to a smaller area
and that is done
by combining both of them together
so you can see bring that aeration and
the sedimentation in one
tank in some sedimentation we can put a
membrane
okay and that could be a compact system
and a better quality which called
membrane bioreactors
okay still if you look at it here uh
if you look at it here in this one
settling
of biomass is not a problem okay
unlike in a conventional activity
process that's becomes a very attractive
and you get an
excellent quality water very often we
could reuse it
and these are the advantages of membrane
system membrane bioreactors
and you can see a typical membrane
bioreactor system
and you can see it has a small footprint
doesn't have a smell order problem you
don't need too many
workers because you can automate the
whole system
amount of sludge produces less and also
the system is
has a higher biomass and robusting and
it can
take into a shock loading much better
than
conventional electrical process
and it's very attractive selling point
of this technologies is
we have a very high quality
effort and the effluent is without
suspended solids
without organics reduce nitrogen
so this water treated water could be
reutilized
so it's become more and more attractive
to use these
membrane bioreactors and the membrane
bioreactors
can come into three typical
configuration
you can have an aeration tank and put
the membrane outside which called
external membrane or you can put the
membrane
directly into an aeration tank this is
we call the second generation
membrane bioreactor which becomes a
relatively
not popular these days what we want
today is
we keep this membrane outside the thing
which is called membrane
airlift system okay or sometime we call
side stream membranes so the main
biological process takes place here
the membrane is kept outside the systems
this is becoming more and more popular
okay if you look at on this one
activate such process and a membrane
bioreactor and
of course membrane bioreactors in all
terms
very attractive all the disadvantage of
our
activates with process can be overcome
by memory but
only issue there is is for membrane
bioreactor system to avoid or to
eliminate
the bio falling or deposition of solids
on the membrane surface what we do is is
we need to aerate huge amount of we need
to send huge amount of
air bubbles something called surface
scrubbing
and that leads to very high energy
consumption and that is one of the main
issue make membrane bias
unattractive it is energy consumption it
is not the membrane performance
and what it used to be 10 years ago okay
so now to overcome this energy thing
what we are moving today is is membrane
aerated
biphobia and in a membrane bioreactor
we use a membrane to remove the biomass
so get a very high quality water but
membrane aerated biofilm reactor
we do it differently we use the membrane
not for filtration but we wanted to
provide
oxygen through the membrane so membrane
function
is not for filtration it is used for
diffusion and the idea is is
as i said in these two process only 30
of oxygen we use
actually utilize so that means 70
percent has become wasted
whereas in this if you're diffusing you
could achieve
as significantly closer to 92 percent of
the
oxygen can be or air can be utilized for
biodegradation process
so that is what's the attractiveness
okay
that's what we call membrane aerated
bird
let me brief you a little bit more on
the technology
okay here you can see a membrane
okay specimen okay in which air is
allowed so the air is passing through
the oxygen this
diffuses through the system and
surrounded by the
membrane fiber the biofilm will grow
both at this concentration
here there's a huge amount of oxygen so
you can have a nitrophiles
and as it goes down the air diffuses
through the thing
the oxygen concentration reduces then
you could have two different
microorganisms growing
nitrifiers and denitrifies because one
is a higher oxygen concentration
low concentration so you can use this
one you can see
you could achieve around 80 plus on the
saving
energy cost using this one maximum
so bioflame is grown on the membrane
surface
okay more the biofilm grows more the
pollutants get
degraded okay so we are moving
away from bubble aeration which is used
in membrane bioreactor
to diffuse variation so air is diffuses
through the membrane
so if you look at how it look like in a
systematic way you have a raw sewage
or all wastewater do a pre-treatment
exactly like membrane bioreactors like
okay maybe a micro screen
primary sedimentation etcetera and do a
pre-treatment depending on the thing
then you put into a reactor okay so now
the reactor in which
you can see air is diffused through the
membrane
so air is never sent as a bubble so as
is diffuse through
almost all the oxygen is consumed and
that is the
strength of the system so now the
biomass will grow here
both nitrification denatrification
organic removal
takes simultaneously and the biomass is
taken out
and goes into a next at clarifiers
time okay has small sedimentation time
okay the biomass is removed and treated
waters
taken out and this waste water meets
both
organic and the nutrient removal
requirements
this is a sort of a conceptual system
now the
supplied air could be a air
or in some cases it could be a pure
oxygen okay that could be
anything but at the moment we are
working only on the air as a
industrial application
if you look at a working principle okay
so you can see the oxygen
okay supply through the membrane and it
diffuses
through the membrane so it's more
important
the membrane should allow the air to
diffuse through the system
okay it's very important okay normally a
hydrophobic membrane okay
supply of oxygen through the lumen of
membrane oxygen
diffuses through the membrane surface
okay and now
as it diffuses oxygen concentration at
the
surface of the membrane it's very high
so you will have
okay aerobic condition which
promotes an autotrophic bacteria which
are the
nitrification okay and the organics
are removed here and as it goes down the
oxygen concentration comes to
small close to zero then the
denitrification and oxygen condition
is taking place okay so from
conversion of ammonia to nitrite right
okay
so here you can see a membrane we call
self-respect membrane to achieve the
aeration
depending on the conditions for moth
nitrification and denitrification
can takes place these are the
classic environmental engineering
equations i think i'm not
going to these i presume the previous
presentation
process chandra pointed out this so i
think these are very classic
but what i want to say is two conditions
one is nitrification
and denitrification one we need high
amount of oxygen
one you need a very low amount of oxygen
so these
two conditions can be achieved one
system okay
and it's also is very interesting
simultaneous nitrification
and denatification can take place on
membrane
aerated bioreactors you can see the
theoretical
concepts began on this one the
eliminates the
need to use two separate tank normally
if you know that conventional activates
such process
if you wanted to remove nitrogen and you
have an anoxic tank from the front and
etcetera
and it's also very important in such
situation
the ph need to be maintained
and here you can see when you do it both
at the same time
it becomes very interesting the
alkalinity consumed in the nitrification
is produced by
the denatrification process that means
there's a less demand
necessity for alkalinity okay so you can
see
an mabr technology is a disruptive to a
conventional wastewater treatment system
so we see
the future of the wastewater treatment
plants
especially in a decentralized system
maybe become very very attractive during
the next few years
and you will see more and more
attractive research what has been done
now to look at it here this is
a cross-section of membrane
lumen and oxygen diffuses from inside
to outside and the pollutants moves from
bulk liquid towards the membrane surface
and it gets
degraded and it's very important here in
this one
the bioflame layer should grow okay the
whole process depends on
the biofilm layer growth and the
thickness of the biofilm growth
we don't want the bioframe layer to be
very small
then you will not have a nitrification
identification and we don't want the
biofilm to
too thick then in the end of the process
you will not have sufficient
uh okay had to be come for
denitrification process okay
so we need to come into this very
carefully
okay the major functions here supplying
oxygen which supports the biomass growth
and the membrane material as the air has
to pass through
it has to be hydrophobic and you could
have a different
type so i've come into that in the next
slide slide
the configuration could be a honor fiber
a flat sheet or tubular
but today in a commercial activities
it is only holder fiber and tubular
becomes attractive
and the design parameters
unlike in membrane body like this the
membrane thickness
and the specific membrane surface areas
plays a very important role
let me take you to three minutes a small
video clip please look at this one
then i'll come back to the next
discussion urban infrastructure
bacteria need oxygen to break down
wastewater over the past hundred years
oxygen was delivered
by bubbles a very energy intensive
process
with bubbles rising quickly bacteria
struggle to get oxygen
with 70 wasted oxymen changes that
why no bubbles that's so old-school our
oxygen is still a bit direct
no hassle with oxymoron bacteria grow on
gas permeable membranes for the direct
supply of oxygen
thousands of membranes are held in
cassettes like this
enabling more effective bacterial growth
on each membrane wall
meaning bacteria work more efficiently
without oxygen bubbles
the cassettes are inserted into an
oxymet cage which can be part of a
package plant
or retrofitted into an existing tank
okay that tells you a typical
maybe a process how it looks like on a
video okay
now let me take the next part
how these mabr membranes in terms of
engineering configuration the first one
we call
dead end configuration so the membranes
are placed here
the air supplies comes here the bottom
part it's closed
that's means we call it a dead end i
oxygen
transfer efficiency okay but it's also
is very important
uh in the later part okay as
oxygen passes through the nitrogen can
back diffuse
into the system so it's not that
attractive
the first generation mabr people worked
on this one
but today we prefer because to
have a cross flow configuration whereas
outlet
okay the carbon dioxide the
gas outlet and the nitrogen will be
removed here
which avoid the back diffusion but
of course when you talk about oxygen
transfer
this might be less efficient compared to
the dead end okay
so but still from a practical point of
view
today to a large extent we prefer
to use a cross flow configuration okay
so keep that in your mind and mabr we do
not
like to use the dead end configuration
okay in a practical applications
i would like to share this information
with you okay
now if you look at it a little bit more
engineering point of view
okay uh how the bio frame will look like
this
okay so if you have a conventional
contribution
okay and here you can see this one
normally oxygen okay you have an
attachment surface
okay so aerobics oxygen is here
so aerobic is on this side and the
nitrifiers is on this side
it's a very classic conventional
coefficient okay
both aerobic and neutron rich so exists
at the biofilm surface
okay you can see this one this one but
if you look at it in
mabr one the oxygen is coming from this
okay
so the nitrifier concentration is on
this one okay that is where the
oxygen is necessary and you can see on
this
the oxygen concentration produces here
okay
and then you can see this is aerobic
electrophiles are here okay so low cod
and
high deo concentration near the bio
frame attachment surface
favors the growth of nitrifying
bacterias
and whereas on this part favors the need
the nitrifying condition
so you can see you could create in a
biofilm
unlike in this case both nitrifying
and denitrifying conditions it's very
interesting
so that can be put into another way or
we can see this one
so membrane surface this is a waste
water so you can see
here lumen and the membrane surface and
the waste water
so oxygen concentration is very high
here
and when it comes to here the biofilm
okay this is waste water it's almost
become zero
so you can see different parameters so
cod concentration is very high here
and with the cod concentration at this
point becomes
almost zero okay so you can see this in
aerobic autotrophs aerobic ectodrops and
anoxic heterotrophs you can see this one
what happens in this system
this is what happens okay in a
memory aerated biofilm reactor
and that could be put it onto this angle
so you can see
the oxygen is keeps moving the biofilm
grows the b o d is pushed
from the bulk liquid as it goes within
and the nitrate comes out here
the nitrogen okay you can see this one
very clearly
how the biofilm growth is taking place
okay
which can be used again
okay so here you can see this is what we
call membrane
and the biofilm and what is important is
how do you maintain the thickness of
this biofilm
we don't want the biofilm thickness to
be too big
or too small as expected okay and
as with the time like a trickling filter
the biofilm need to be removed
continuously
okay and we need to create the condition
so that biofilm could be removed as some
detachment of particles
or sludge which could be carried to the
next
unit operation of sedimentation
biofilm thickness due to particle
attachment and detachment
depends on substrate availability and
the mixing
condition the reactor so this is the
most interesting
the engineering part of the membrane
aerated bioreactor design
let me move into that next part in terms
of membrane today
to do this aeration there are three
different types of membranes i use one
is micro porous membrane
okay so unlike it's like a micro
filtration air is
passing through the pore and the pores
size should be as small as possible
so that the air is allowed to pass
through this one
as a bubble okay
the second one is a dense membrane like
a silicon membrane
okay there is no pore but air is
allowed to diffuse through the membrane
okay it's
very interesting which called a dense
membrane uh we are working on this type
of membrane
earlier we also do a lot of work
okay the oxymerm is one company which is
manufactures a very interesting
and dense membrane but there is also
possible today
both diffusion
uh sorry microporous and the dense
membrane can be combined together which
is called
composite membrane so more and more the
new membrane manufacturers who are
moving
from membrane to be used as a filtration
that used to be a big marker
it will continue as a big market but if
you look at
what the future market of membrane
technologies
using membrane as a diffusion process
like this type of thing
where people are working on a diffusion
a composite type of membrane okay
in terms of configuration only two
types are very attractive what is the
tubular one okay
you can use this one also spiral wood
it's exactly like
ro memory okay let me take you to
one more video clip how the spiral would
membrane works
in a membrane aerated bioreactor
biological treatment
in an msc mabr plant
is made up of multiple mabr modules
such as this one shown inside a module
tank there is a spirally wound membrane
sleeve with spacers
as an airflow spacer separates between
the walls of the membrane sleeve
a water spacer separates between wraps
of the sleeve
oxygen from the air diffuses through the
membrane into the water side
where there is dissolved ammonium as a
result
a nitrifying biofilm develops on the
surfaces of the membrane
nitrate is generated as a product of the
nitrification process
and discharged back to the water these
conditions are enabled by the presence
of a high concentration of biomass
suspended in the water body the
suspension
known as mixed liquor tends to settle
within the water body
periodic release of air from the bottom
mixes the entire water volume
and homogenizes the mixed liquor mixing
flow follows a pattern of an air lift
rising through the spiral spacings and
flowing downwards through the core
short mixing durations a few times per
hour
are sufficient to sustain the mixed
liquor
the suspended solids for the process are
provided by a secondary clarifier
like in the activate sludge process
mixed liquor is fed to the clarifier
where it is separated by gravity into
two streams
a concentrated sludge at the bottom and
a clarified effluent at the top
the sludge is circulated back to the
process and the clarified effluent is
discharged
for direct reuse or further processing
the biology okay that one presents
very clearly how spiral wound membrane
works
in an mabr reactor and a commercial one
so that gives you an
idea of what's happening in the field
now let me tell you something about
factors influencing mabr treating
both organic and total nitrogens okay
one is
membrane packing density it's important
and oxygen supply rate dissolved oxygen
ph and it's very important ph and
alkalinity because
we are looking at simultaneous
nitrification death nitrification
and hydronic retention time and it's
also very
important we should have hydraulic
retention time
as small as possible okay
organic loading weight okay and
very important for to have simultaneous
magnification and denaturation
the ratio of cod to nitrogen ratio
should be somewhere around five
okay and thickness of bioflex these
are the influencing parameters those of
you are interested in
conducting research or looking at a
research direction
i just summarized these are the factors
you might have to look into that
for developing and working on maybe
let me take the next 10 minutes
summarize some of the application and
what
level of this technology may be
technology today is still
in between the pilot to the industrial
scale okay
there are few industrial scales but
it is not as strong as
membrane bioreactors today membrane
bioreactor is
is for domestic wastewater it is a
proven technology
the amount of research you can do which
is very marginal
but if you look at mbbr there are a lot
of potential
okay for young researchers like what
you can see the type of research work
has been done i just summarized
okay it is used for landfill leaching
pharmaceutical industries ammonia rich
synthetic wastewater domestic wastewater
and it's quite interesting it's not only
worked on the domestic one
it's also can be used xenobiotic
or very what do i call um
extremely uh polluting organic
pollutants okay um let's say for example
acetate two lawn and all these
components
uh organic pollutant which can
biodegrade easily by aerobic process
the problem is is we cannot use and
activate such process because
these are very volatile compound okay so
when you use an
air an activation process a significant
part of them
will strip out as a air pollutant so
all the aerobic process can be utilized
conventional
membrane bioreactor process cannot be
used because of this
walletization issues whereas these
things let's say for example we worked
extensively a component called
acetonitrile okay it's a strong organic
pollutant
highly volatilized and easily
biodegradable in the aerobic process
but we cannot use conventional process
because the air could strip them out
so what we do is we use membrane
aerated bioreactors so where membranes
diffuse through the system
so there is no volatilization and the
complete degradation can take place
so this is one interesting
domain so where membrane aerated
bioreactors can be utilized so
specifically for
industrial pollutions containing
volatile
organic compound which can easily
biodegrade
okay in aerobic process
you can look at this one okay treat a
deaf rule okay
uh the difference okay
you can see inlet you can see an outlet
and it is very important
the outlet of the membrane it's not
crystal clear like membrane
bioreactor in membrane direct sometimes
the treated effluent is better than the
drinking water
in terms of turbidity some some
situation
because it's a membrane filtration but
here please understand
it is not filtration it is an effluent
from a sedimentation
okay so if you wanted to reuse it okay
and you need to
think of what type of application you
can use it's important okay
so like here you can see some of these
applications are
pointed out right treatment of high
loading
pharmaceutical waste water and as i
told you here many of the pharmaceutical
compounds will have
toxic organic chemicals and which are
easily biodegradable you know aerobic
conditions
and you can see this one can be utilized
okay high cod
and nitrogen removal rates can be
obtained membrane aerated
bioreactors okay so here you can use
simple
pvdf membrane okay and you can see that
there are other application reduction of
nitrate and perchlorate from groundwater
and some situations okay when you want
to remove this one okay
it's easy to use okay
membrane aerated bioreactors i will not
go into the details but if you are
interested
you can read these documents you can see
that how
and what domain is being utilized but
when it comes to
today commercially
there are two leading companies okay
zen and zebido ge as this
general electric has bought this company
called zeelong
and this is one of the commercially
available membrane aerated bioreactor
company
okay another one is oxymet okay
this uses a porous membrane this uses
sort of a dense membrane okay
and i like to tell you there are many
new membrane developers
are working on this domain and we
ourself
are working with some companies because
many membrane manufacturers
look this domain as an interesting
future
growth potential of membrane okay so the
next five to ten years
you will find a huge number of membrane
new domains to use not membrane
bioreactors
but to work as a membrane aerated
bioreactor systems
okay and the industrial applications
okay let's say
there's a company called fluence the
first mainland
u.s membrane aerated pilot pile
pilot plug in which is
uh used okay which is to meet the
california's
stringent uh
nitrogen removal standards okay with a
capacity of
11 meter cube per day so it's more of a
pilot scale so you can see this one
so you can see the membrane aerated
bioreactors have been neutralized since
in brazil okay it has been in
spain still somewhere between
to pilot scale to a industrial scale not
a big scale okay
a semi pilot or semi industrial
scale i would say this one okay there
are a lot of
more and more industrial scale
applications have been taking place in
different parts it's become very popular
the fluence
membrane technology was originally
developed in israel
so it's quite popular in israel okay to
use this technology
so there are a variety of applications
you can see this one where that's uh
this type of system can be utilized in
package systems
simple systems exactly like membrane
bioreactors you can download this one
and you can package it it's becoming
more and more popular
so here you can see this one this is
really comforting influence it says
yes okay i'm in a meeting can i call you
okay uh sorry for the call
so you can see this one okay now
let me take the next 10 minutes
what type of research we are doing at
ait
okay that tells you what are the
research potential
okay and what type of work and this
tells you
we wanted to by download
for increase the removal efficiency of
organics and the total nitrogen the
bench scale
membrane the issue we addresses
is normally we can achieve
organic removal very high in
conventional mbr systems
but the problem is is when you wanted to
remove the nitrogen
it becomes a difficulty so that is why
we wanted to use
membrane aerated bioreactors okay and we
also want to do this one
as a short hrt as possible okay
so here we can develop a membrane
dense membrane it's a oxymoron a
reactive
okay and the waste water is added onto
the theme
and we could achieve a certain amount of
nitrogen
so we could not achieve the full
denitrification process
for that we what we did is we created
added in this reactor a type of
gel pv agent where the denitrified
microorganisms are captured and grown so
the wastewater is introduced on this
organic and nitrification takes place
here and the denitrification takes place
here
part of the denotification on the
biofuel the risk
taking place here this experiment set up
so
i'll show you this video so to tell you
some snapshots hello everyone
my research topic is enhancement of
organic matter and total nitrogen
removal in
maybe are using bile carriers
and these are the objectives of my
research
as you can see in this video there are
two reactors with two different
configurations
and now i will explain you about their
operation first i will explain you the
operation of the reactor on my right
side
as you can see it has three compartments
which are hydraulically connected
and the compartments on either side
contain the membranes
here are the characteristics of these
membranes as you can see here
the biofilm has already grown on the
membrane surface
in the middle compartment there is pva
gel it is a type of bile carrier
and i have already grown denitrifying
bacteria on them
and these are the characteristics of
these bile carriers
and this is how i grew bacteria on them
in addition
i have provided good mixing in the
middle compartment using a mechanical
mixer
so the whole purpose of this
modification is to improve
denitrification
now let's see how this works first
synthetic waste water with the required
cod to end ratio is prepared and stored
in this storage tank
then using this peristaltic pump it is
pumped into the reactor
with the required flow rate using pu
tubes
waste water enter the reactor through
the valves on either side of the reactor
as waste water enter the reactor first
to get treated by the biofilm on the
membrane surface
thereby nitrification and
denitrification take place by this
uniquely stratified biofilm after that
the waste water enter the middle
compartment through the perforated walls
thereby further denitrification takes
place by the biomass inside pva gel
after getting treated like this the
treated water is collected in the bottom
of the middle compartment
as you can see there is a very small
diameter glass tube attached to the wall
of the middle compartment
water is taken to the top through that
tube
and through this pu tube it is taken to
a settling tank
after settling down the heavy particles
the treated water is collected in a
separate collecting tank
like this
and now i will explain the operation of
the other reactor which has a different
configuration
this reactor contains a different
membrane and these are the
characteristics of the membrane
this reactor has a cylindrical shape so
the procedure
in here is also the same as the previous
waste water is prepared and stored in
this storage
tank and it is pumped into the reactor
using this peristaltic pump
here also waste water enter from the
bottom of the reactor and get treated by
the biofilm on the membrane surface
then the treated water is taken out from
the top
after that it is taken to a settling
tank and after settling down the heavy
particles
the final effluent is stored in a
separate tank now let's see the results
of these two experiments
here are the results of objective one of
the research here i have calculated the
required operating pressure at each hrt
using the otr experiment results which
have been carried out previously
now let's see the results of objective
two here is the cod removal performance
and here is the total nitrogen removal
performance of the two reactors at
different hrts and cod to n ratios
thank you
hello everyone my wrist okay
that video clips tells the type of the
research we have
conducted in iit okay and this research
resulted in a publication okay and you
can see it was published in the bio
resources technology
report and this is one of the work on
this one in parallel to this
we also did another research okay
studying on the mabr performance on a
xenobiotic compound
and as i told you earlier
we looked at certain xenobiotic
compounds
because which can volatilize normally
but it can be biodegradable aerobically
so that we cannot use an accurate such
process
so we use the diffusion system
may be a systems and we can date the
similar type we can see the reactor
the waste water is exactly passes
through this reactor
you have this membrane
dense membrane which is used for
aeration
okay the aerobic degradation takes place
through the biomass
okay and we can see this one and we
the effluent comes out here and the
effluent performance and etcetera
admission
and which is again published this is
american society of civil uh
uh civil engineering american journal of
environmental engineering
or american society of civil engineering
it is published okay you can look at
this
information okay just to tell you type
of the work
so from this laboratory work doing
fundamental research
currently we are moving into this to
develop
a pilot scale experimental work which
talk about
mabr to treat actual domestic wastewater
within our campus okay we are going to
the next scale
uh we are working with some actually
developing
and how nitrate and phosphate could be
removed
and the focus for us is most importantly
developing a very compact and fully
automated
system so we have developing systems
within the campus so that the we could
monitor them okay from a distance so the
idea is is
to promoting decentralized wastewater
treatment systems
using this type of system okay let me
move into the next part i would like to
tell you that
what are the interesting research
developments taking place
i talked about the conventional one now
i want to tell you
what is the research development because
if anybody like to work on mabr
which direction you should look into
that some of the research
direction themes involved in this the
first one is
people are working on two stage startups
instead of having a one single stage
nitrification and denatrification taking
place
it's also possible sometime much easier
you could break this into two components
a nitrification
on one side okay and the d notification
is a second stage
okay because you needed two different
conditions and you can create this one
when you want to have denitrification
because you need some organics because
the problem here is most of the organics
is removed
on this one and when you come to the
denitrification
you don't have sufficient amount of
organics okay and that is what we found
so the way we have developed we have
this
the pva gel compartment in that
compartment we need to add
organics for denatification take place
so similarly
you need to look that two reactors
approach could be an interesting one
okay
whether to go for a simultaneous
nitrogen and denitrification
or we could have like you say
you need to have two different sources
so we need to add
a source of organics okay to create that
ratio of cod2 nitrogen ratio it's very
important
and people are working on this the
intermittent aviation
step feeding and periodic back washing
these are the things
we need to look into that as i told you
we don't want the biofilm to grow too
much so sometimes we need to remove that
by frame how do you remove it some type
of back washing might be interesting
and there are researchers working on
this one
high breed mabr system okay so
what we're doing is they have an
anaerobic zone
depending on the feed condition okay
because you need to get the correct c to
n ratio
okay and this compartment may be our
problem so you might
be good to have anaerobic zone first
okay to reduce the amount of cod as much
as possible
and the nitrogen balance comes with it
then you can have the last part
okay a fine bubble variation okay
well there are people are working on
different configurations
one of the interesting work okay we are
working at the moment is is
looking at the membrane configuration so
for example
how bioflame is done okay one
thing is is the micro biofilm could be
kept in one strong
stage or you could sorry not by frame
the fiber could be kept in there
one straight or you could make this
the membrane fiber bit loose
because when you keep like this okay the
membrane is not
relaxed okay so what happens is here it
is very interesting concept when you
want to filter water
okay like a water treatment and etc
please keep in mind
many of the conventional honor fiber
membranes
are designed for filtration application
so that means
you have the water to be filtered okay
so but they are not designed for a
biofilm to grow
okay if you want the biofilm to grow
in a membrane if you look at it here if
you like a big bundle
the inner part of the fibers there is no
possibility of biofilm to grow
so what we need to do is we need to
redesign
the membrane and we redesign it in such
a way
there are published papers you can see
custodial et cetera
working on these there are people who
researchers are working on this
how you redesign so that the biofilm is
grown hundred percent within the whole
fiber body
it's very important okay we don't want
the biofuel to go
only on outer surface okay outside but
we need to do
it so we are working on this i think
there are a lot of research
goes on this and this might be an
interesting thing
let me come to the sort of
my last part of my presentation the
cutting edge of
mabr application could be looked into
two things
one is a bioreactor characteristic
second one is operating condition
in a bioreactor characteristic you need
to look at membrane permeability
specific surface area the membrane
surface chemistry
okay say for example traditionally
membrane produces produced membrane
so that the biofilm will not grow on the
surface
okay but here we want exactly opposite
we want the biofilm to grow on the
surface so that means
the chemistry need to be changed
okay and we need to work with organic
chemist
how do you create membranes in which
biofilm can grow
whereas 99 percent of the industry is
producing membrane
in which membrane biofilm will not grow
different condition okay we need to look
at it
how do you do this aviation regimen
etcetera
now the second part is the first part is
bioreactor characteristic the second
part is we need to look at the
operating condition how do you operate
your reactor
i think if you work on a nitrification
and denitrification
in a biological process the cod to the
night regeneration is very important
and many situation it doesn't meet the
optimum condition
so you need to consider how do you
create that optimal condition
between five to ten okay
if your feed water is not good if it
doesn't
you need to develop a strategy to bring
that range
to our best notification d notification
hydraulic retention time we need to
bring down
okay all the industrial applications
works around 10 hours
and our dream is to bring less than
three to
somewhere between six to three hours
it's a challenge
and that is what will take us further
okay
intramembrane pressures temperature ph
as i told you okay cross flow velocity
at what velocity you do that
how do you control bioflame and etcetera
this all
looks into this hydrodynamic
channeling i told you you have a bundle
the whole biomass is on the outside
there's inner part not much so there is
a
hydro dynamic channeling takes place
by frame thickness bio flame
micro uh
morphology and the density and we need
to work very strongly with biofilm
and biological people and how whether
it's what type of biofilm is growing
how do you control and etcetera it's
very important
we cannot just look this
research just a chemical or
environmental engineering
we need to work very strongly and very
closely with microbiologists performance
can be looked at
vod cod removal suspended solids
nitrogen removal sludge yield okay it's
quite
interesting the sludge yield is simply
much
okay quite attractive and also we need
to look at
aeration efficiency as i said we are
going to have this cross flow mold
so we also have to make sure the system
is efficient enough
okay the exhaust air which comes out
okay what do you do with that okay and
we can
think about them etc we'll come back to
the next one
let me finish off my presentation with
this last slide
uh my i've been working on this field
for last five years
uh let me summarize on my understanding
what are the research gaps in this
domain
where young researchers like you might
be able to work
difficulty in maintaining an optimum
biofilm thickness
as i said we are simultaneously two
process taking place
in a single reaction okay if you want to
do that
you need to control the biofuel
thickness it's a challenge
and please keep in your mind you're
talking not on a flat shape
okay like for example in trickling
filter it's a flat shape with only one
surface
but here you hold a fiber it's a bundle
what happens
inside the core and what happens outside
is different
time requirement for initial biofilm
formation
exactly a trickling filter and an
activated process
activation process you can start maybe
you can start like this
but m a br you needs
sufficient time the biofilm has to grow
it can take between anywhere between
two to four weeks okay so we need to
think about that
how do we accelerate in a real
applications
sensitivitiness of the bioframe to the
changes in ph and temperature
and salinity it's very important
possibility and membrane defects such as
whether what happens okay if your
pre-treatment
failure whether make the membranes as a
bundle
as we see in a conventional
membrane bioreactor process okay if your
pre-treatment is not good
especially if your waste water contains
air
and if the pre-treatment doesn't take
the air outside
the and the air will go inside the
bundle
and make the bundle into a like a tangle
okay
so that it cannot move and that creates
a lot of operation problem
same thing can happen poor understanding
mechanism see there's not much work has
been done
from a laboratory pilot scan and how do
you move the industry
that is something we need to work with
might be very challenging
integration of mabr with other advanced
oxidation technologies
improvement in nitrification and
denatification process
within the reactor still
we were able to achieve only around 60
to 70 percent of the
total nitrogen removal but our aim is to
to 98 how do you achieve that that's
important
significant reduction in hydraulic
reduction time as i said
if you wanted to achieve an iron
nitrogen removal
one of the ways is we can increase
hydraulic retention time
and then it becomes not attractive
so we need to look at it how we can
couple
or modify this whole process the
hydraulic reduction times can be reduced
and total nitrogen can be
uh sorry hydraulic retention time is
reduced with the
total nitrogen reduction is removal is
increased
let me finish my presentation it's
almost an hour
it may be a believe me or not it's a
game changer with respect to
energy footprint of biological treatment
process any of the biological treatment
process will work
and if there is an energy consumption
issues
which is a problem in an accurate size
process
any of the aerobic process please
understand this
is in competition with aerobic process
it's not in competition with
anaerobic process with dr howard going
to present on friday
okay so this is if you're talking about
aerobic process
if you're worried about your energy
footprint or energy consumption mabr
will be a really a game changer okay
very attractive and there's a lot of
scope
for working on this with this note
thank you very much let's have next few
minutes for discussion
questions thank you okay
uh thank you vishu so i will
will i will uh probably
uh the
already some question right uh
beta
okay please be there okay
can i start with a checklist in that way
yes there is some questions here so many
questions actually
okay we will uh okay read the
questions okay i'm saying that i have
uh this is okay is it may be a system
applied for industry or still
study research phase okay
ah yeah i can i can can i answer the
question one by one
ah yes yes please yes please if maybe a
system is applied in
industry or still in study research mabr
is
to large extent in a research
but it moved from laboratory to pilot
scale
okay but there are few uh
there is only one published
paper on a large-scale mabr in china
for a pharmaceutical industry uh it's
it's a very big plot but there are a lot
of
how do i say
holes in the indus scale application
i think there is lot more research need
to be done i don't
i will not say it is industry scale
application
fully but it's moving it has moved to
certain extents
okay is that okay the first answer
yes okay thank you okay
how to make sure the separation of
microbial layer
in a bioframe is separate clearly if
there's any probability to mix them
in one layer um i think the question
comes is that what type of microorganism
presence aerobic or anoxic
okay depends on the amount of oxygen
which can diffuse through okay so at the
closest to the membrane surface
you have an aerobic system and as the
oxygen diffuses through
so you cannot separate it out if the
separation
takes place naturally by the presence of
oxygen okay
okay so it's naturally separately
speculative it's not separately it is
one biofilm
the inner part for what thickness it
depends on the oxygen
diffuses through okay so if you look at
a
fiber the fiber is like this long fiber
okay on the top you'll have more oxygen
at the bottom you'll have
less oxygen as it passes through okay
the biofilm on the top of the fiber
and the biofilm at the bottom of the
fiber will be different
because the amount of oxygen diffuses is
different so
that's the that's an important part
okay how about mass transfer resistant
of oxygen
water membrane layer micro are there any
civilian
this is a very important issue
these are the ones the chemical
engineers are working on this
okay and in fact we also doing a lot of
work on i did not present it here we
also work on
the resistance oxygen what we call
oxygen transfer rate how to improve the
oxygen transparent
and that's why i said what type of
hydraulic circulation we keep
within the reactor to improve the oxygen
transfer rate
okay and also i told you how you design
your membrane
do you design as a bundle or you design
a bit loose
and we use this word relaxation rate
that we need to be study honestly that's
one of the part of the
research we are working number three
number four do we need
a mixing system inside aviation time
yes that's as i said you need to look at
it
how is the oxygen transfer rate so
sometimes it's good to have
hydraulic mixing okay
for two reasons to improve the oxygen
transfer rate
second thing we don't want the membrane
biofilm to grow too thick okay
and we want the biofilm to remove just
remember
trickling filter if the biofilm grows
the water cannot penetrate percolate
so you have flooding of tickling filters
similarly we don't want biofilm to grow
too much
so we need to mix it and continuously
remove the wireframe
so you need to have mixing condition
depending on your reactor okay so
we don't need another of mechanical
mixer like uh architecture
yes you saw the reactor i we showed you
now an aborted scale
we use that one depending on
oxygen transformation okay
can i go to the next one from irvine
yes yes is there is a company which
already has a
cas treatment plant wants to convert it
do
do they only need to switch activate
such process too
yeah see please understand
if you are using membrane bioreactor
you don't need a secondary sedimentation
okay
but if you're using membrane aerated by
affirmative
you need a secondary clarifier okay
please understand the biomass has to be
removed so secondary clarifier is
necessary
okay as i said it's become very
attractive
when you're focusing on nitrification
and denitrification
okay okay if your focus is on nitrogen
removal
yes it becomes so you can easily convert
a conventional activity forces
into an mabr using the secondary
sedimentation
okay is it still
possible to simply use air rather than a
pure oxygen
please understand that industrial scale
we will never use pure oxygen
okay because it