Measuring And Controlling Foam In Chemical & Pharmaceutical Bioreactors [How]
In bioprocess industries, foaming is a major technological issue as it could cause an undesirable side effect on the process. Therefore, it needs to be detected and controlled in a best way possible.
The understanding of ‘foam’ is simple as we can find it in our day to day life in milkshake, bath foam etc., but practically it has more complex structure when it comes to bioprocess industries.
The precise and reliable methods of measuring & controlling of foam can directly contribute to improvement of product quality & yield and thereby lessen the overhead cost.
Foam control is done by addition of anti-foaming agents, which improve process control, increase in efficiency.
The problem of foam formation varies according to the type of industry and adversely affects the productivity. It causes serious difficulties in the areas of pharmaceutical, food & beverage, waste water, chemical treatment plants etc.
How foam is generate?
The pharmaceutical Industry uses fermenters for production and involves stirring and mixing of air and gas for operation. However, these natural organisms create unwanted bi-products which supports foam stabilisation making it easy for stable foam production.
There are the chances of liquid completely turning into foam if not controlled on time. Anti-foams are generally used to protect from foam generation, but it leads to unwanted side effects which is difficult to control.
Overall, anti-foam usage can alter the end results significantly, therefore, measuring and control of foam generation is necessary.
Precise foam control is important in pharmaceutical industry during fermentation process. The industry deals with health sector, therefore, accurate result during the process used in the production of medicines, antibiotics, vaccines and many other drugs is critical.
Bad effects of Foam
- The excess foaming results in reduced efficiency of the process and hence heavy cost
- Since large volume of foam occupies major portion of fermenter/vessel it reduces productivity
- There are chances of foam entering in pipe lines and causing damage to pumps, which in turn increases down time.
- Adding anti- foaming agent manually to restrict the foam formation, leads to consumption of expensive anti- foaming agent with low process yield.
- Degradation of quality of final product due to excess foam or anti foam agent resulting in product loss & increase the waste
- Increases environmental pollution
Challenges of foam measurement
- It is difficult to carry out measurement of foam level and foam-liquid interfaces
- Finally the performance can be affected by different factors including frequent change in the density of foam and gradual layering or fouling of the instruments due to by-products left in the bioprocess.
- Delayed sensing of level instrument decline the accuracy of measurement & control techniques
Solution for Foam Control
Techtrol Foam Detector ‘Suresense’ uses the patented IMA Sensing® technology developed by Hycontrol. Sensors are able to discriminate between the residual deposits of foam and product that build up on the sensor itself and the foam being created in the process.
Effectively the Foam Detectors ignores the inevitable fouling while continuing to monitor the foam. No matter how heavily the sensor is coated, or how dense and sticky the layer, its unique construction enables it to keep measuring foam throughout the process cycle.
Anti-foaming agents or de-foaming agents are widely used to prevent foam formation. The sensor range have single or dual set points. It can also be used with controller to provide o/p of 4-20 mA corresponding to foam level/density which helps to control foam automatically.
The foam sensor measures the foam level and releases small amount anti foam agent which is precisely controlled by the controller to reduce the foam. Precise control of addition of antifoam avoids overdosing and saving of antifoam agent and simultaneously improves efficiency.
Across the globe, companies are spending billions of dollars every year to deal with foam problem and its effects on their business. In addition, focus has to be given on the long-term ill-effects of the disposal and dispersal of anti-foaming chemicals on health and environment.