The document provides an overview of fermentors, which are devices used for fermentation, a metabolic process transforming nutrients into alcohol and acids. It details the objectives and basic functions of fermentors, types of fermentation techniques, and essential components such as agitators and sensor probes for monitoring conditions. Furthermore, it emphasizes the importance of fermentation media and lists necessary activities for effective fermenter construction.

1. FERMENTOR ASSEMBLY AND
CULTIVATION CONDITIONS

2. • Fermentation is an energy-yielding anaerobic
metabolic process in which organisms convert
nutrients (typically carbohydrates) into alcohol and
acids (such as lactic acid and acetic acid).
• Fermentation is perhaps the most ancient biotechnological
discovery known to man.
 A Fermentor is a device that accomplishes the
fermentation process by the help of certain
microorganisms, and that is the reason why it also
refers as “Biofermentor or Bioreactor“.
Fermentor is designed in such a way so that a higher
value of product could form by the microorganisms by
utilizing a small amount of media.

3. Objectives of Fermentors:

4. Basic functions of a fermentor:
• It should be reliable for long-term operation.
• A fermentor should be capable of being operated aseptically
or should provide sterile conditions.
• The bioreactor provides adequate aeration and agitation for
uniform mixing of the contents in the vessel.
• It should consume less power.
• A fermentor equipped with controlling probes that maintain
the temperature, pH, oxygen level etc.
• It facilitates the passage of inoculum and media into the
vessel.
• A bioreactor does not allow excessive evaporation loss.
• It minimizes the labour input for the operation, harvesting,
cleaning and maintenance.

5. Types of Fermentation techniques :
• A batch culture is a closed culture where
microorganisms ferment a given amount of nutrients
within a defined time period. The fermentation takes
place in batches. That means the products are
removed at the end of one fermenting session and the
fermenter is filled with the nutrients for the second
fermenting session.
• The advantages of batch culture are the easy setup
and control of the cultures and the ability to carry out
different cultures at different times.

6. Cont...
• A continuous culture is an open culture in which the
supply of nutrients, as well as the removal of the
products, is continuous. Here, the microorganisms
maintain an exponential growth since fresh media is
added continuously. Hence, most of the bacteria are in
their log phase.
• The advantages of continuous culture are continuous
fermentation and high productivity. But, different
cultures cannot be fermented in the same fermenter.
Also, continuous cultures are more prone to be
contaminated.

7. Components of fermenter are as follow:

8. • Depend on the type of fermenter we are dealing with.
1. Glass lining small scale.
2. Coated with stainless steel large scale.
• Separate top plate from body.
• To prevent contamination and to prevent air leakage.
• Depending on the body of fermenter, it is classified into three
types:
a. Gasket seal.
b. Lip seal.
c. O ring seal. In case of stainless steel.
 Material must be inert react and contaminate (if not).
In case of glass body

9. • Introduce sterile air into mixture with the help of pores.
• Present at the bottom of the tank.
It is of three types:
Firstly invented, small scale, small pore size-blocked by microbial
growth.
Pressure drop across sparger.
Pore size=6mm(large), not blocked.
Both in small and large scale.
Advanced form, mostly used.
larger pore size.

10. • Attached to motor at the centre of mixture.
• Used for mixing purposes(nutrients, oxygen, micro-
organism), make the mixture or vessel environment
homogenized.
• Agitators also evolve from simple to complex.
 It is classified as: simple turbines, disc turbines, closed
turbines and propellers.

11. • Another type called double helical agitators used for mixing of
materials from top to bottom.
Some times agitators and spargers can be used in combination.
• Metal strips, 1/10th of vessel diameter .
• Attach to the walls.
• As impeller mix or rotate the media, vortex created.
• It prevent vortex to cause.
• If vortex not stop then media moves out of the tank.
• As a result mess and contamination cause.
• It also help agitator.
• It help agitator by creating pressure as a result proper mixing.

12. • With out baffles good mix at the bottom of vessel but not at
top.
• Thus by creating pressure, baffles make mixture homogenized.
With out baffles With baffles

13. Valve and steam trap:
• Valve attached to fermenters are used for
controlling the flow of liquids and gases in variety
of ways.
• Valves are of many types.
• Simple ON/OFF valves which are either fully
open or closed .
• Valves which provide coarse control of flow rates.

14. • Safety valves which are constructed in such a way that
liquids or gases will flow in only one direction.
There are two main types of valves..
1. Pressure reduction valve are incorporated into
pipelines when it is necessary to reduce from higher
to lower pressure, and be able to maintain the lower
pressure in the downstream side .
2. Pressure retaining valve will maintain pressure in
the pipeline .

15. Steam trap:
 Steam trap is used to remove any steam condensate
which accumulates in the pipping to ensure optimum
process conditions.
Sensor Probes:
• PH Sensor; sense PH , maintain PH levels.
• Temperature sensor; which sense temp .
• Foam probe; to sense foam formation .
• Oxygen sensor ; monitor dissolve oxygen level.

17. • Fermentation media: it contains large amount of nutrients this
media is used in fermentation industries for production
economically important products.
Role of fermentation media:
•During fermentation process organisms enjoy luxurious metabolism
with high amount of nutrients, optimum conditions.
•Due to presence of large amount of nutrients the micro-organisms
become hyperactive and consume excess nutrients and results in
partial degradation of fermentation media.
•The waste product excreted by microbes may be the desired product.
•The substrate given to microbes should not reach inhibitory conc.
levels as it may result death of cells.
•Excess substrate may increase osmotic pressure and effect enzyme
activities in a cell.
•Microbes excrete this excess substrate in the form of partially
digested fermentation media.

18. A fermenter should be constructed in such a way that It
can make provisions of the below activities:
1. STERILIZATION
2. Temperature
control
3. pH
control
4. Foam
control
5. Aeration
and agitation
6. Sampling
point
7. Inoculation
points for micr-
organisms, Media
and supplements

19. Diagrammatic representation of fermenter: