Rotary vacuum filtration
- Rotary vacuum filtration is utilized in the removal of microbial cells from a broth. The solution is vacuumed in an upward manner crossing a filter septum that is removed by a positive displacement pump. The filter cake is then removed to provide a clear fresh surface for filtration after every rotation. The filter can be utilized in the removal of enzymes, cells, mycelia, and proteins.
- Any changes to engineering and process parameters have an impact on the KLa and should be considered when performing scaling calculations and evaluating bioreactor platforms. The major variables that affect KLa are gas bubble size, mixing, airflow rate, and medium properties. When the gas bubble size is reduced, gas residency time and surface area increase, and hence bubbles stay longer within the culture. An increase in the residence time of the gas improves the KLa value. Mixing, on the other hand, is used to eliminate concentration gradients and temperature. Mixing efficiency is a significant factor that affects both scale-up and performance in a bioreactor. Another factor is the airflow rate. KLa increases due to the availability of high oxygen levels. While higher levels of KLa are desirable, considering the actual conditions of operations is crucial for associated process costs and cell viability.