Frequently Asked Questions (FAQ)

The control of dissolved oxygen inside a DASGIP bioreactor bases on a control loop adjusting several set-points of the so called “actors”. Potential ways to increase oxygen transfer are oxygen enrichment, gas flow and/or agitation adjustment. Usually the control strategy is to change the actors’ set-points sequentially as defined in the cascade. For example in cell cultivations agitation usually is not changed for shear reasons and the gas flow might be kept minimized if the media tends to foam. So the usual set-up of the DO-cascade might be depending mainly on oxygen enrichment from air to pure oxygen and then shifting to a slight flow adjustment. This may be completely different when working with robust microorganisms and high cell densities. Here, a higher agitation often is required to prevent from oxygen limitations, followed by increased gas flow and then by oxygen enrichment.
The DASGIP system supports multiple gassing strategies and specific agitation modules providing various ways of DO control. For example mass flow controllers in the gas mixing module allow both precise oxygen enrichment and flow adjustment.
Using DASGIP Control software all three cascade parameters can be defined independently and simultaneously for all included batches. This allows automated DO control meeting individual demands. Unlike other bioreactor control systems the DASGIP system additionally features a unique online visualization and online changes of the DO cascade. This helps users to adapt and optimize DO control at any time during the process run.

Follow the link to find a screenshot of the online editable DO cascade.

For more information contact service@dasgip.de or call +49-700-DASGIP-AG/+49-700-327447-24