To understand the significance of each part of the bioreactor,
Please run the simulator in following steps:
1. Press Start
2. You will see the bioreactor and its different control units.
3. Speed control system
* The purpose of Speed Control System is to provide mixing of reactor contents (Microorganism and Medium).
4. Gas Supply System * The purpose of Gas Supply System in the bioreactor is to supply air which serves as the source of the oxygen to the growing cells. * Enter any value (< 400) as “Set air speed” & press RUN. * The air flow will start from the air cylinder and will pass through rotameter air filter etc leading to bubbling from radial sparger. The bubbles will be broken down by the agitator to release the oxygen trapped in it. * Press enter NEXT button to go to “Temperature Controller System” 5. Temperature Control System * The purpose of Temperature control system is to maintain the right cultivation temperature in the bioreactor. The temperature is measured by the temperature sensor (Blue). This value is then compared with the set point value
and depending on the error the temperature manipulation is done by passing either cooling (blue dots) or hot water (red dots) in the jacket of the bioreactor. * Press enter NEXT button to go to “pH Measurement & Control system”
6. pH measurement and Control System * Enter any pH value say 5.0 in the set point and press RUN. * The pH in-side the bioreactor is measured by the sensor (orange) and is compared with the set point and depending on the error either acid (green) or base (orange) peristaltic pump is triggered from the controller. * Press enter NEXT button to go to “Dissolved Oxygen measurement and Control” system. 7. Dissolved Oxygen measurement and Control * Enter value of Dissolved oxygen level in the bioreactor say (30% Saturation) and press RUN. * The Dissolved oxygen inside the bioreactor is measured by magenta sensor, the value is compared with the set point and depending on error the controller action is activated. For example if the Dissolved oxygen in the
bioreactor is registered low the controller speeds up the air supply and/or the agitation speed to increase the level of dissolved oxygen in the bioreactor. Similarly if the level of the dissolved oxygen is measured low in the
bioreactor it will reduce the rate of supply of oxygen &/or RPM in the bioreactor. This way the set point value of 30 % saturation level of dissolved oxygen is maintained in the bioreactor. * Press enter to the NEXT button to go to FOAM control system of the bioreactor. 8. Foam Control system Foam is defined as dispersion of liquid in gas and it is invariably produced in any cell cultivation primarily due to presence of nitrogen and protein material in the medium. Though it is essential to keep the nitrogenous material
in the medium as high as possible because it is essentially required to give good growth however the foam is on the other hand highly undesirable as it can lead to heavy loss of medium from the bioreactor. The foam is detected
by Red sensor and antifoam addition is triggered through peristaltic pump to kill the foam. Peristaltic pump adding the antifoam solution (blue bottle) is made to work at a very slow speed primarily to add as minimum amount
as possible. Over addition of antiform may create serious problem in isolation of the product from the fermentation broth.