We are discussing organic chemical technology
course, and we have discussed module 1, module
2, module 3 and module 4 of this course. Today
will be discussing module 5 and which will
compromise sugar and fermentation industry,
especially the alcohol, which we are getting
from the molasses, which we are getting from
the sugar plant.
So, the coverage of the lecture that will
be introduction of the sugar industry historical
review of the sugar industry because this
is one of the oldest industry, you can say
the then the profile of sugar industry process
step in the sugar manufacture byproduct from
the sugar plant, alcohol from molasses different
type of alcohol, alcohol from biomass.
As you know the sugar industry is one of the
most important agro based industry in India,
and has an important impact on the rural economy.
India is the first two largest sugar producing
country in the world, with sugar production
during 2007-08 was 263 lakh tons, there are
624 sugar factory in the country. As on 31,
2009 sector wise break up is given in other
slides.
But this is the importance of the sugar, you
are saying the different type of sugar that
we are making and the even that they have
lot of the changes, in the quality of the
sugar from brown to white. That means, the
even from the smaller particle sugar to the
cubical more larger size of the crystals.
So, these are the different type of the sugar
that we are making.
So, different type of the sugar and alcohol
sugar, gud and khand, raw sugar because this
was the khand, khandsari that was the oldest
and that is the you can and the initial stages
was there in the development of the sugar
industry. And raw sugar, refined sugar, soft
brown sugar, coffee crystal granulated sugar,
larger and in smaller size sugar, sugar cubes
different shapes that we are getting alcohol,
alcohol that will be the industrial alcohol,
absolute alcohol and anhydrous alcohol that
we are making alcoholic beverages and beers,
wines, whisky, brandy, liquors different type
of the alcohol beer because that from the
ancient time, we have been using the alcoholic
beverage. Let us discuss about the historical
review of the sugar cane and sugar manufacture
in India.
It is universally acknowledged that India
is the home land of the sugar cane and sugar.
The reference of the sugarcane cultivation,
its crushing, and preparation of the gur in
Atharva veda as well as Kautaliya, Arthasatra
that has been reported. It is reported as
sugar came to India from New Guniea centuries
before the Christ. The Indian offering the
contain 5 amrits that is the during the any
religious function, we use the milk, curd,
ghee, honey and sugar, which shows the importance
of the sugar in our daily life. And sometimes
we also compare mithas that is the sugar,
in our daily life.
Sugar was made in India during in the fourth
and sixth century. Crystals prepared from
the juice was called sarkara. The word sugar
is derived from the sarkar that the word we
are using large, larger lumps was called the
khand. It is from India that the art of making
sugar is spread to Persia and world over.
First sugar plant is started at Aska in Orissa
in 1824.
The first vacuum pan process sugar was set
up at Saran district in Bihar, in 1904. By
1931-32 there was 31 sugar mills with total
production of 1.5 lakh tones. Whereas, the
consumption was around 12 lakh tones. So,
the you can imagine the requirement of the
sugar that was there. In 1932 India sugar
industry protection act was promugalated and
by 1935-34-34, 111 sugar factories producing
4.6 lakhs tones of the sugar came into existence.
1940-41 there were around 148 sugar factory,
with production of 11 lakh tones.
Growth of the Indian sugar industry and that
was only after the independence, in the organized
sector after industrial policy resolution
in 1948, and industrial act in 1946 that were
there and the growth of the cooperative sector
of the sugar industry, after that the lot
of the development in the sugar production,
and the sugar mill setting of the sugar mill
came into existence. Later establishment of
the national federation of the cooperative
sugar factory was there. And the first cooperative
sugar factory was Paravara cooperative sugar
factory, which is in Maharashtra. And Maharashtra
is also one of the leading sugar producing
state in our country. This is the profile
of Indian sugar industry and the number of
the sugar factory because many of the number
that may vary, but this is the figure which
we I got by 2012.
Private sector 245, public sector 62, cooperative
317 and total number of the sugar mill are
624. Capacity is varying very widely, processed
technology remaining the same, but lot of
the improvement technological development
that has been done in the sugar plant and
the old sugar mill. If you compare the old
sugar mill and the new sugar mill, there is
lot of difference in the process technology,
regarding the refining of the sugar and also
the capacity of the plant.
In 2010 and 11, sugar cane was planted in
4.98 million hectares across the country of
which 1 million hectares was in Maharashtra,
for 2 million hectares in Uttar Pradesh official
estimates show. This is the actually we see
Maharashtra and UP and Bihar these are the
some of the major sugar producing states in
India.
This is the cane production and sugar production
figure as on 2010-11. The total cane production
that was 346 million tones sugar production,
24.20-24.50 million tones.
As I told you that the UP and Maharashtra
are the two largest sugar cane producing states
in the country, accounting for more than 80
percent of the annual crop production. India
is one of the largest producer of alcohol
in the world. There has been a steady increase
in its production over the last 15 years according
to the fresh statistics. Actually, you see
the molasses to alcohol conversion. Now, that
has become very important in case of and that
will be discussing separately. How we are
making the molasses and the importance of
the alcohol from the molasses in the chemical
industry.
India is the a dominant producer of alcohol
in South East Asia region, with 65 percent
of the total shares, and contributes to around
7 percent of the total alcohol beverage imports
into the region. More than two-thirds of the
total beverage alcohol consumption, with the
region is in India according to the figure
in newly compiled alcohol atlas of India.
There has been a steady increase in the production
of alcohol in the country, with the production
doubling from 81.2 million liters in 1992-93
to 1.654 million liters in 1999-2000 and was
expected to treble to 2300 million liters
by 2000. The production actually the data
was not available. So, that is more than this
what we are having today. Sugar industry is
highly seasonal industry.
This is one of the problem in case of the
sugar industry with the season lengths of
the about 6-18 weeks for beets, and 20 to
because beet is also one of the source of
the sugar, but it was here. We will be discussing
mostly about the sugar and from the sugar
to alcohol and 20-32 weeks for the cane. So,
processing in the sugar manufacture, what
are the various steps involved in case of
the. Now, let us discuss this manufacture
of the sugar.
Extraction of the juice, this involves washing
shredding and extraction of the juice from
sugar cane by milling. Here you find lot of
the development that has taken place in milling
to increase the extraction of juice from the
cane because the overall economic sugar recovery
that is one of the very important factor.
In case of the economic just to have more
and more economic. Next, step after the extraction
of the juice the juice purification here also
lot of the development earlier it was the
carbonation.
Now, we are also having we are using the sulphilation
using this S O 2 that is also being used.
So, the extractive juice is purified using
lime and C O 2 for removing the non sugar
substances from the juice sulphilation using
S O 2 is also being used. Then the next, step
after the juice purification, the concentration
of the juice by evaporation, we are having
the number of multiple effective operator
for evaporation of the purified juice, which
we are getting that is around 15 percent.
So, that it may be crystallized so, the after
the concentration of the juice that is going
to from the evaporation, it is going to crystallization.
Crystallization of the concentrated sugar
solution to sugar crystal here that the crystallization
part that is very important, because the growth
of this crystal size, that is very important
which is keeping. Actually, the product better
product quality centrifugation because the
separation of the sugar crystal from the molasses,
at the residue.
So, centrifuges separation of the crystallize
sugar molasses are left behind after the centrifuging,
which is used for the production of the alcohol.
So, the molasses which is that is one of the
very important by product of the sugar manufacture.
Then the further refining of the raw sugar,
the raw sugar is dissolved filtered and crystallized
again to get high grade refined sugar. Let
us discuss slightly more detail about the
sugar refining part, sugar refining part.
Actually, affination raw sugar mixed with
the saturated syrup. Then centrifuged. Surface
impurities are dissolve and removed carbonation
using milk of lime and C O 2, removal of impurities
color and other impurities, which are present
in the juice. Sulphilation process it may
be the cold sulphilation, or the sulphilation
of the after the after liming. Here in case
of the cold sulphilation that is the acid
sulphilation, we call it because the pH lower,
in the second when it is along with the lime
it is the alkaline sulphilation that is these
are the other extraction, involve in case
of the sugar refining.
Because now, you seen the market wide variety
of the sugar crystals available larger size,
smaller size more whitish in nature, colorless
even the in color also will find the different
category of the and so, that that also the
how the cost of the sugar that is fixed that
is the purity of the product, color of the
product larger size, lower size, smaller size
of the crystal. So, for that the further refining
that is very important.
So, what we are doing? Filtration, char filtration
is where we are using the activated carbon
for removal of the impurities, and then crystallization.
This is the flow diagram of the sugar manufacture
of the cane sugar, cane that is going to the
various crusher from where we are getting
the juice, and that is going where we are
adding the lime C O 2, S O 2 and purification
that is taking place and here we are that
is going to separation, removal of the press
mud from this. And so, after the filtration
or through the washer, the cake is separated
and the filtrate that is going to the multiple
effective evaporator.
So, in the multiple effective evaporator,
the juice is concentrated and the further
refining again it is being done, and then
the vacuum pan crystallizer we are using.
And the finally, in the process we are getting
the crystal sugar and the mother liquor for
the further evaporation, crystallization and
black liquor, strap molasses for the production
of the alcohol. So, this is the flow diagram
and the even here also the number of development
that has taking place in case of the refining
as I told.
Now, we are also using in addition to activated
carbon ion exchange resign has been also used
for the purification 
of the sugar, what are the major development
has done. Because the one of the major problem
that has been as you know that the recovery
of the sugar that is decreasing especially,
in the when at the last sixties of the sugar
cane production means the, during the summer
at the end of the around the March and April
the so, recovery date goes on. So, what has
been done in case of the sugar industry they
have continuously modified development that
has taken place to increase the recovery of
the sugar.
So, for that the new mills they are having
the installation of the fiberliser, which
is resulting in the reduce energy in milling,
and increased extraction of the juice because
that is very important, we cannot afford to
lose the juice because if you are losing the
juice it means, you are losing the sugar.
So, increase the number of the rollers, so
that the more and more milling and crushing
that may be there, and extraction of the juice
is more. Reduction in the crushing RPM of
the roller, sulphilation process, activated
charcoal filtration and then as I told you
the use of the ion exchange resin, for the
further purification hydrogen peroxide, sugar
remelt ion exchange decolouristion process
that has been added into some of the sugar
mill, where they are extra purified sugar
they are making.
These are the some of the commonly term used
in the sugar industry that is the first, which
I told you at the first step in case of the
sugar manufacture; that is the milling process
of extraction of juice from the sugar cane,
breaks you need to used to express concentration
of the sugar solution. This is the just to
measure a the concentration of the sugar solution,
which we are getting.
Bagasse that is left after the extraction
of the juice from sugar cane, and this is
also one of the very important bio-product
of the sugar industry and normally, all the
sugar industry they are using bagasse for
the power generation in their bagasse based
power boiler, but now there is in lot of discussion.
Why not to use these bagasse for other purpose?
Because you can produce paper from this, and
let the other fuel be made available to the
sugar industry.
So, that the more and more bagasse and that
we are getting for the making of the paper
another waste that we are getting from the
during, the after the clarification of the
juice that is the press mud waste after clarification
of the juice, that we are getting that is
containing line. Now, they have suggested
because for making some of the bio fertilizer.
So, press mud along with the concentrated
waste from the memory separate process. They
are mixing they are that is going for the
composing. And defecation process is used
for producing raw sugar, these are the some
of the commonly term used.
Then the sulphilation purification using sulfur
dioxide, carbonation and that term we are
using purification using carbon dioxide. Massecuite
the mixture of the sugar crystal syrup produced
by crystallization. Molasses syrup of left
after centrifuging, and separating sugar crystal,
then the spent wash was after separation of
the alcohol from the fermenter. Let us come
discuss in more detail about the process step.
As sugar contains 70 percent that is not sugar,
sugarcane contains 70 percent of the water,
14 percent of the fiber, and 13.3 percent
of the sucrose about 10 to 15 percent sucrose
and this is the region why normally, the recovery
part which is there it is around 12 to 13
in most of the mills. So, if it is 12 to 13
it is sometimes it may be, but not more than
and 2.7 percent impurity, the yield of the
sugar depend mostly on the quality of the
cane and the efficiency of the extraction
of the juice. That is why I told you the milling
process and extraction of the juice, and the
installation of the faberizer that was the
reason for going to increase the extraction
of the juice.
Next step which I told you in this, when I
summarize the that was the in this the abstract
which I give you the about the various steps
involved, that is the crushing milling and
squeezing of the juice though a series of
the pressure. Mill rolls containing grooved
walls weak juice and makeup water is added
as an extractant before squeezing just for
the, to have more and more extraction that
we are increasing, we are using the weak juice
there.
After crushing and extraction of the juice,
bagasse is left as a residue, which is about
33 percent of the total cane crushed bagasse
is used as a fuel for the boilers and the
still. Whatever the bagasse, we are producing
around 10 to 15 percent of the bagasse is
surplus and that is being used by some of
the paper mills, and number of paper mills
based on the bagasse has come due to the increase
in the production of the sugar cane. Purification
of the juice of the removal of the impurities
by addition of the calcium phosphate followed
by addition of the lime to precipitate, the
impurities in the form of the colloid because
the purification parts also is that is very
important, to get the good quality of the
sugar crystal.
Then the evaporation and crystallization,
the clarified juice is concentrated in the
multiple effect evaporator to about 40 percent.
And concentration, the concentrated syrup
is again bleached by passing S O 2 through
it. Concentrated sugar solution is then sent
to the vacuum pan, where thickened syrup is
boiled 3 to 4 times and then sent to the crystallizer,
where separation of the sugar crystal takes
place.
Then comes the purification for arriving the
double carbonation using C O 2 and double
sulphonation using S O 2. The clarified solution
goes to evaporator and the under flow of the
clarifier goes to the rotary filter, for removal
of the impurities as cake which I told you
the rotary filters, we are using the filtrate
containing sugar from the rotary filter is
recycled that is the filterate, we are using
during the extraction stage. Then it is sent
to the high speed basket centrifuge, the concentrated
of the purification for this separation of
the sugar crystal.
The syrup is concentrated and cooled successively
to obtain one or two crops of the crystal.
The final mother liquor called the molasses
is sent to the distillery for the production
of the alcohol by fermentation process, where
a counter current flow of water is used to
remove the sugar from the beet slices, if
you are using the beet.
These are the some of the figures yield of
the various product from the cane crushed
bagasse press mud, and again the press mud
that will depend up on the type of the purification
you are having whether, you are having the
double carbonation or the double sulphonation
and then the molasses.
These are the some of the waste product that
we are getting from the, this is we start
from the sugar cane, cane tops and the leaves
that is the waste. And that can be used for
making the compost, fuel, power generation,
animal feed that is normally it is being used
as a animal feed, but the dry part that can
go that can be used for gasification also.
Then the bagasse, which we are getting after
the removal of the juice; then that is going
to the bagasse fire boiler, bagasse fliers
that can be used for the and bottom ash from
the boiler that will go to the land fill and
the bagasse, which is there that is having
good amount of the carbon also, that can be
used as a adsorbent or for making of the fire
briquette.
Similarly, the other use of the bagasse that
may be the as I told you the now the number
of paper mills that has been they are using
the bagasse as a raw material, and paper and
board, news print also. Alpha cellulose, building
composites along with the bagasse and some
of the polymeric compound that you can make
the building composites, domestic fuel furfural
from the bagasse that is possible, poultry
litter and the mulch composed wax animal feed,
land fill and the fermentation industry, animal
feed.
So, this is for the molasses that is an press
mud that can because that can be some organic
part is there that can be used as a fuel also,
and that can be composed also because as I
told you now, the because all the solid waste
has to be utilized and. So, along with the
reject from the membrane separation process,
they are making the compost also.
Now, let us discuss about the ethanol manufacture
because you see the ethanol, that is one of
the very important product of the. And many
of the sugar mills they are integrating they
are having the sugar production, as well as
production of the ethanol. So, that is link,
but many of the mills they are having the
only the sugar making part and so, the molasses,
which ever they are producing that is supplying
and this is under control.
India is amongst the two largest sugar producing
countries in the world, and convert the molasses
from sugar plant to alcohol. India is the
fourth largest producer of ethanol in the
world and second largest in Asia. India produces
about 2.75 billion alcohol annually liters
that is the alcohol. The demand for portable
alcohol has been ever increasing and the number
of the your plants, which are making ethanol.
They are also making the alcohol portable
grade alcohol, apart from the industrial grade
alcohol, which we are using.
Today 95 percent of the ethanol is produced
by fermentation, and only 5 percent is produced
from the petroleum feed stock by ethylene
route, because there are number of routes
for ethanol is there, but the major production
of the ethanol in India. And in some other
part of the world, where the lot of the sugar
is produced like Brazil and the other part
of the world where the sugar cane production
is more, it is the fermentation of the molasses
that you are making the alcohol.
Ethanol has become one of the important product
as alternative feed stock for large number
of the organic chemicals, and fuel that will
be discussed in lecture 2, while discussing
the ethanol as the bio fuel and as the chemical
feed stock. Ethanol is an oxygenated fuel
that contains 35 percent oxygenation, which
reduces the particulate and the N O X emission
from the combustion and that is the reason
why, that has been recommended blend of the
alcohol along with the gasoline. Now, let
us come to the historical review of the alcohol
production.
So, for the alcohol as a beverage is concerned
that is mentioned in the ancient time, back
to the Vedic period around 200 B C. Drinks
soma and sura that was the fermented beverage
and that has been mentioned in our religious
books also. Alcohols are also used in the
many alcoholic preparation, and the tradition
Ayurvedic medicine also because that has been
the part of the medicine also, the alcohol
and now you will find the many of the syrup,
cough syrups and all those they are containing
some alcohol also.
Fermentation of the fruits to alcohol known
to the primitive humans. Usage of the beverage
since, the ancient time and process of beverage
is well established that the smaller scale
operation that was there earlier. Period of
the colonial rule saw slow, but steady raise
in the alcohol production. Development of
the fermentation and production of the alcohol
from molasses started with the development
of the sugar industry, number of the sugar
mills that increase and the production of
the molasses was there, and the molasses was
made available to the fermentation industry,
for making the alcohol that we call will the
distillery.
This is the various types of the drinks that
we are having. So, for the portable gate of
the alcohol is concerned a wide variety of
the not only from the molasses route, but
other routes are also there beet, sugar. All
those thing they are also from the beet also
we are making some of the grape of the fermentation
of the some of the fruits also, we are doing
and making good quality of the drinks.
Foundation of the scientific understanding
that was only after the Louis Pasture, who
developed the micro biology further, the development
is micro biology and knowledge of the microorganism
because we are using yeast here in the fermentation,
and the fermentation technology led to the
development of the alcohol industry. Production
of the lactic acid that was in 1884 that is
the. So, for the fermentation is concerned
the first distillery in India was at the Kanpur
in 1805 by Carew and the company that was
in Kanpur.
Alcohol is now being used for the portable
liquor, as chemical feed stock, as solvent
and as oxidant various routes for manufacture
of the alcohol because molasses is one route,
molasses from the fermentation of the alcohol
from the fermentation of the molasses. Alcohol
from lignocellosic biomass because now, the
lot of the work is going on also, this process
from the biomass that was well developed earlier
also, but there has been some problem in the
pre treatment of the biomass.
And so, with the development of the pre treatment
processes and the removal of the lignin, now
it is considered as biomass that can be also
a promising source, future source of the alcohol.
Alcohol from the starchy feed stock petrochemical
route were we are using the ethylene, and
from the ethylene esterification and hydrolyzing
various products that we can make.
The molasses is the residue left after the
extraction of the crystallized sugar, and
is one of the major byproducts of the sugar
industry. Ethyl alcohol is made from the molasses
by fermentation process using the yeast enzyme.
The various steps involved in case of the
alcohol production that is the molasses handling,
the molasses you are getting, because in many
of the mills they are not having the fermentation
plant, and there were alcohol production is
not there. So, that is being some plight through
the tanker to the different mills which are
having your fermentation plant.
So, the molasses handling fermentation feeding
system, preparation of the yeast inculam,
propagation of the yeast from for fermentation
distillation of the dilute alcohol for removal
of the impurities because normally, in the
fermentation. During the fermentation process,
we are producing dilute alcohol and that alcohol
that has to be concentrated, if you are interested
for absolute alcohol, further removal of water
to make the absolute alcohol or even anhydrous
alcohol.
Now, let us discuss the various steps in more
detail the molasses handling involves weighing
of the molasses and pumping of the molasses
to the molasses tank, from which the major
quantity of the molasses is transferred to
the fermenter because that is a continuous
process. Preparation of the yeast inculam,
propagation of the yeast, yeast material is
prepared in water cooled, yeast vessels by
inoculating molasses with the yeast and then
transferred to the aerated, yeast activation
vessel to allow time for yeast cell multiplication
and after that it is being added.
Fermentation involve the fermentation of the
fermentable sugar by microorganism and formation
of the alcohol, and other byproduct yeast
is the commonly used for fermentation of the
glucose to ethanol after the fermentation
alcohol 7 to 8 percent strength is obtained,
as I told you this is the we are getting the
dilute alcohol. The fermentation is the exothermic
process and heat is generated and so, continuous
cooling has to be there during the process
after C O 2 is removed.
And as I told you the removal of the heat
is necessary to maintain the temperature in
the fermenter. High temperature, lower the
alcohol productivity nutrients are added to
the fermenter intermittently, depending up
on the requirement because all the micro process,
if indeed the nutrient sulfuric acid is added
to adjust the pH of the fermenter liquid.
Excess foaming in the fermenter is controlled
by antifoam solutions.
During the normal operation treated yeast
cells recovered from the fermentation process
are washed, recycled from the yeast treatment
system to the activations vessel. After they
transfer to again to the fermenter because
one the growth of this yeast that has taken
place then continuous, the process that is
going on what about the yeast that is we are
generating in the process that is again recycled.
After the fermentation is complete the dilute
liquor that may be, as I told you 7 to 8 percent
or that will vary 8 to 10 percent alcohol
is preheated, and pumped to the beer still
where the alcohol of 95 and were the 50 to
60 percent. And other volatiles like aldehydes
are distilled or from the top and send to
the aldehyde column, for separation of the
aldehyde this is the impurity that is the
present, in the process and other low boiling
impurities. The residue from the bottom of
the column is known as slops, and tillage
are discharged and treated for recovery of
the energy or concentrated and used.
This is the reaction that is and during the
process of alcohol manufacturing, lot of the
C O 2 that is formed and that C O 2 some of
the mills, they are also marketing, this C
O 2 they are collecting, this C O 2 and that
has been used for the various purposes, because
it may be also used for making of the some
of the useful chemicals.
The alcohol drawn from the aldehyde column
is sent to the rectifying column. The azeotrop
because here the alcohol, and water that is
the famous azeotrop that you are making, it
is containing alcohol about 95 to 96. See
it is taken as top side stream from the rectifying
column. So, that is the azeotropic mixture
is there and azetropic distillation is taking
place to have the higher concentration.
This is the process you see the molasses,
molasses it is going to fermentation process,
it is going to distillery and then, the final
products ethanol that you are getting.
This is the in detail about the process, which
I discussed. Molasses it is going to be the
diluter were we are adding the sulfuric acid
and after the sulfuric acid, it is going to
the fermenter, fermenter this is was I was
telling this C O 2, C O 2 that is going to
the scrubber after there is a carbon dioxide,
this is going outside from this cover. The
fermenter after the fermentation, we are getting
the here the because the from the fermenter,
fermenter slice will be also there and your
alcohol, dilute alcohol that is going to the
further concentration yeast.
Again as I told you the yeast, which is produced
during the process that is also multiplication
of these it is there. And so the yeast of
distraction again it is going to fermenter
after that what is do the analyzer column,
were we are concentrating further concentrating
the alcohol. So, a spent wash is used, what
is that spent wash? That is a very useful
byproduct in case of the alcohol, and this
is being used and this is having very high
C U D 1 lakh.
So, that is the sometime problem also if you
are not using the properly this spent wash.
And so, they are generating the anaerobic
treatment of the spent wash that are generating.
And so, this is what we are doing in case
of the sugar industries were they are having
the sugar and alcohol both. So, the treatment
process first it is the utilization of the
spent wash in the anaerobic treatment process
to produce the a methane gas, which is being
used as the whatever, the gases there are
that is being used for the power generation
that is being using the industry.
And then the what about the spent wash after
the even anaerobic treatment that is containing,
you can say around 500 to 10,000 C U D still
highly colored material that you are getting,
after the anaerobic treatment. So, lot of
the challenges the distilleries are facing,
how to further treat this spent wash, which
you are getting after the anaerobic treatment
because that is highly colored, and the C
U D load is very high. Some of the places
they have because normally in some of the
country, what they are doing the treatment
of this spent wash.
Before going it is going to anaerobic treatment,
they are doing the pre treatment and in our
country what we are doing, we are using this
spent wash for the power generation and then
it is going for the further treatment. Finally,
we are getting the alcohol. You see as I told
you, this I will be discussing in detail while
in the lecture 2 that the, what are the different
byproduct that you are getting the molasses?
How to utilize the molasses and they are converting?
This alcohol molasses to alcohol and alcohol
to ethanol and that ethanol that is being
used for manufacture of large number of the
product, this is the actually the flow diagram
of the various product that is one of the
molasses based chemical plant.
This is the product profile of the ethanol
that is the fermented wash, distillation.
So, we are getting the ethanol, spent wash
that is going for the biogas generation, which
I am telling after the biogas generation,
whatever the effluent that you are generated
that is going to the further treatment. Now,
the centre portion control board they are
very much concerned about the distillery because
that is one of the highly polluting industry.
So, the different type of alcohol, which we
are getting that may be industrial alcohol,
portable alcohol and so, that may be the extra
neutral alcohol, country liquor although thing
that is the various type of the product that
you are getting.
Alcohol recovery that is very important in
case of the your alcohol plant. So, this section
involves the recovery the alcohol from the
fermentation section to minimize, the possible
loss of the alcohol along with the generated
C O 2, and sludge from the fermenter. Another
thing that let us discuss because that was
one source and now, the lot of the work that
is going on for the production of the alcohol,
ethanol forming biomass because the biomass
gasification. We discussed earlier while discussing
the coal and biomass gasification, but another
thing that we are interested in utilization
of the biomass just for the production of
the alcohol.
So, technology for producing ethanol from
the cellulosic biomass through fermentation
and chemical hydrolysis, have been developed
from lab to commercial scale. Globally even
if 10 percent of the biomass is used for the
fuel protection, there may be substantial
reduction in the oil consumption. So, it is
being considered the future raw material for
the chemical plant as well as, as a source
of the fuel.
Ethanol thus because the gasification route
that is one route, that can be the gasified
gas that can be used for the making the that
can be synthesis gas that can be as fuel,
or making of the by these chemicals also another
route that is the what, we are having the
alcohol from the biomass. So, there may be
substantial reduction because that will provide
alternative source of the fuel ethanol. Thus
produce can be a promising chemical feed stock
also.
U S based primus green energy has developed
a high conversion efficiency biomass to gasoline
process based on the innovative, thermal,
chemical conversion and the process can generate
416 liters of the gasoline per ton of the
biomass. Lingocellulosic biomass, is available
abundantly and can be used as the alternative
feed stock for ethanol production. Alcohol
from the biomass, what are the process that
is involved in case of the when we are using
the biomass because from you see the during
the 30, 40 also the lot of the work that was
done for the making of the lingo, but the
micro biology that was not well developed.
The pre treatment process were not well developed
and so, the real actually the work that was
started for making of the alcohol from the
biomass, with the development of the pre treatment
technology, and the processes for the removal
of the lingo.
So, lingo cellulosic biomass includes forest
residue such as wood, agriculture residues
such as sugar cane bagasse, corn cob, corn
stovers, wheat and rice straw industrial residues,
such as pulp and paper processing, waste lignin
from the pulp and paper mills and municipal
solid waste and energy crops such as the grasses.
So, this is the actually the some of the biomass
general term we are using for biomass for
these waste material, these have the potential
for the use as a feed stock for the production
of the fuel and ethanol.
The nature and availability of the lingo cellulosic
feed stock in the different parts of the world
depend on the climatic condition another environmental
factor, agriculture practices, technological
development.
Advantage of the lingo cellulosing material
to a larger extent locally, domestically and
provide security for the supply. Generate
low net greenhouse gas emission, reducing
the environmental impact, particularly the
climatic change that we are having because
of the deforestation because of using of the
natural resources. Also, the providing employment
in the rural area.
This is the cellulosic content of the various
raw material hardwood, softwood, nutshells
corn cobs, grasses, wheat straw, rice straw,
cellulose contain hemicelluloses. This lignin
that is creating problem in utilization of
the biomass for the alcohol purpose. Otherwise,
if so for the bio gasification, you concern
no problem and at the same time use of the
these biomass for the production of the paper,
again that will depend up on the cellulosic
content of the your biomass.
This is again some of the agricultural residue
that you are getting.
Technology bio-ethanol from the bio-mass,
what are the technology available? The concentrated
acid hydrolysis, dilute acid hydrolysis enzymatic
because of coming of the enzyme bio-technology,
lot of the improvement in the hydrolysis process
that has taken place biomass gasification
in the fermentation. Biomass gasification,
already we have discussed this is the fermentation
process, from where you can get the alcohol
there, it will be the bio gasification to
your synthetic gas, synthetic gas to methanol
and that methanol again that can be used for
the making of the bio-fuel, this is the ethanol
production per ton of the product, di-product
from the various sources.
Bagasse, rice straw, forest thinning, hardwood
dust and the mixed paper.
This is the cellulose, hemi cellulose and
lignin in the biomass and that is the 40 to
60 percent, 20 to 40 percent hemi cellulose
and lignin 10 to 15, 25 percent. Disadvantage
of ethanol because there has been lot of discussion
for ethanol as a bio-fuel, again that will
be discussed by discussing the importance
of the ethanol as a bio-fuel, but these are
the some of the disadvantages, which has created
problem in utilization of the ethanol as a
bio-fuel.
Higher aldehyde emission, corrosiveness, higher
latent of vaporization, higher evaporation
loss, requiring large fuel tank to lower the
calorific value below 10 percent due to a
disadvantage are not serious because normally,
it tells the reason. Why 5 to 10 percent blending
of the ethanol that has been recommended?
The degree of the when you are going for the
bio-ethanol from the biomass, the degree of
complexity and feasibility of the biomass
to ethanol depends on the nature of the feed
stock. As I told the contents of the, because
the variation in the composition of the biomass
is there, lignin remains a residual material,
after the sugar in biomass have been fermented
to ethanol. That lignin evens the separation
of the lignin that is creating problem in
case of the utilization of biomass. Already
we have discussed these are the some of the
technology that is available.
All the conversion processes in case of the
biomass to ethanol that contains the feed
stock harvesting, transport and storage pretreatment
of the lingo cellulosic biomass, enzyme hydrolysis
of the cellulose in the lingo cellulose material
to fermentable reducing, sugar fermentation
of the sugar into ethanol downstream processing
of the ethanol. So, these are the some of
the steps involved in case of the when you
are going for manufacture of the ethanol from
biomass. So, as I told you the pretreatment
that is one of the problem in case of the,
but that is pre requisite without that you
cannot go for the further other process, which
involve in case of ethanol process.
So, the pretreatment the biomass is a prerequisite
to the biological conversion of the lingo
cellulosic biomass to ethanol. Pretreatment
is done either physically, chemically or biologically
to make the pretreated biomass more amenable
to subsequent cellulose hydrolysis. Pretreatment
after the size and structure of the biomass
as well as chemical composition because these
are the some of the factor that will decide,
the that will the pretreatment impact of the
that will be that will alter the size. The
structure of the biomass, as well as the chemical
composition because some of the impurity that
will be removed, during the pre treatment
process. This already I have discussed in
the, I have summarized.
The various steps involved in case of the
alcohol that is the cellulosic material, which
produce either by acid hydrolysis using sulphuric
acid or enzymatic hydrolysis. Both the process
that is available, both the dilute and concentrated
sulphuric acid are used in the acid hydrolysis.
Dilute sulfuric acid involved milder condition
than the concentrated sulfuric acid hydrolysis.
In acidic in acidic hydrolysis, first convert
cellulosic material to sugar followed by the
conversion of sugar to other chemicals.
Enzymatic hydrolysis of the cellulose another
route for alcohol, enzymatic process requires
pretreatment of lignin cellulose to break
the crystalline structure of the lignicellose,
and remove the lignin to expose the cellulose
and hemicelluloses, because this is the reason.
Why the lignin removal? That has been very
important. Depending on the biomass material
physical or chemical pretreatment methods
may be used.
So, as I told you the physical treatment method
may use high temperature and pressure, milling,
radiation or the freezing. Chemical methods
use a solvent to break apart and dissolve
the crystalline structure.
This is the actually the steps involved biomass,
it will go to the hydrolysis fermentable sugar
and then the residue and then the fermentation
process, ethanol, butanol or the hydrogen
whatever the product that what have.
Technological barriers. Some of the technology
barriers, which need to be addressed in the
efficient conversion of the biomass to ethanol
or the pretreatment sachatification of the
cellulose and the hemi cellulose matrix. Simultaneous
fermentation of the hexose and pentosone sugar.
These are the some of the technological barriers.
All conversion schemes involves following
basic step already I discussed the feed stock,
harvesting pretreatment and then the finally,
the hydrolysis. So, this was the how we can
alternative source of the ethanol from the
biomass is there. In the next lecture, lecture
2 we will be discussing about the ethanol
in more detail about, how the ethanol that
can be used for the production of the various
useful chemical. And that is being used in
many of the plants, some are integrated and
in some of the cases they start from the fermentation
and then the ethanol that is being used for
the manufacture large number of the chemicals.
And one of the because even the starting of
the some of the chemical that was through
the ethanol route not it was the petroleum
route. But it was the ethanol route as some
of the example are the Indian glycol, vam
organic which is now synthetic chemicals barely
and some of the other plants, sumaya chemicals
all are they are they were using the alcohol
for producing the large number of the chemicals,
which are now being made from the petro chemical route.
