Ion exchange technology is widely applied in industrial biotechnology market, many clients think ion exchange is a simple process, even thinking ion exchange is more for equipment than process; However, it is not a easy job to design an good ion exchange system with minimum operating costs and for easy operation; In the process of engineering implementation, we need to consider at least the following factors.
Ø Fully understand the feed characteristics
Ø Ion Exchange thermodynamics (exchange equilibrium)
Ø Ion Exchange kinetics (exchange speed)
Ø Optimum design of the process (definition of adsorption, desorption, regeneration, rinsing...)
Ø Resin selection based on specific products
Ø Equipment customization based on process design
Ø Global process optimization taking into account of ion exchange step
According to the feed characteristics, three types of ion exchange system commonly used in different conditions.
1. UP-FLOW ion exchange
Advantages of up-flow ion exchange system.
Ø Compact resin loading
Ø Up-flow adsorption
Ø Down-flow regeneration
Ø Resin volume 40% less.
Ø Less chemicals due efficient regeneration.
Ø Coupling with membrane pretreatment, activated carbon eliminated for HDE production.
Ø Full of fluid in column, good microbiological controlling due oxygen eliminated.
Typical application:
Glucose De-ash, Maltose De-ash, Raw Sugar Decolorization
2. Continuous Ion Exchange
Advantages of continuous ion exchange.
Ø Minimum buffer tanks for feed, product, water and chemicals.
Ø Continuous supply from upstream and to downstream.
Ø Significant water saving due rinsing columns in series
Ø Less dilution of product due sweet off columns in series.
Ø Less evaporation needed due higher product concentration.
Ø Less chemical consumptions as well less effluents
Typical application
Lysine, arginine, gulonic acid, vitamin C
3 Fully Automatic Fixed Bed Ion Exchange
Even though continuous ion exchange and up flow ion exchange systems have many advantages, but fully automatic fixed bed ion exchange still has some unique advantages in some other processes.
Ø Applicable when the ion content in the material is low and the adsorption time does not match well with the regeneration time
Ø Frequent decontamination is required on the same column, which is complex for continuous/up flow ion exchange.
Ø Easy maintenance needed from operation point of view.
Ø In addition, fixed bed ion exchange can also reduce water/chemical consumptions by setting reasonable buffer tanks.
Typical application
Citric acid, Lactic acid, Inulin...