The Continuous Oscillatory Baffled Reactor is considerably more effective in distributing heat than traditional Stirred Tank Reactors. This has particularly strong benefits when applied to scaled-up production.

There are two key drivers for the improved heat transfer performance:

• The process has improved mixing characteristics. Fluid forces near the walls are as strong as those in the centre of the column because of the combination of oscillatory motion with the presence of baffles that enhance radial mixing within the reactor.
• The vessel diameter is considerably smaller - rather than having a large tank with a diameter measured in meters, a COBR will rarely exceed 250mm in diameter, thus fluid renewal over the surfaces of a COBR is much more frequent than traditional batch stirred tank reactor. This helps to remove of thermal gradients and ensure more uniform heat transfer rates.

The issues associated with heat transfer in scale up are virtually non-existent due to the ratio of reactor diameter to length and the continued ability to generate such flow patterns in a vast range of column diameters.

Case Study - Heat Transfer Coefficient in NiTech's Oscillatory Baffled Reactor

The following provides an indication of the range of heat transfer coefficients that can be obtained using the oscillatory baffled reactor.

Figures are based on:

• Cp = 2000 kJ/kgK
• k = 0.182 W/mK

Within the range of figures indicated, mixing intensity (amplitude and frequency) is the key factor that affects the actual heat transfer rate.