Power, gas dispersion and homogenisation characteristics of Scaba SRGT and rushton turbine impellers.

The Scaba SRGT agitator with six blades when gassed draws between 1 and 0.8 times the ungassed power in fluids of low and moderate viscosity respectively. Under similar conditions, the gassed Rushton turbine draws 0.5 to 0.4 times the ungassed power. In addition, some three times more gas can be handled at the same ungassed power by this SRGT before flooding occurs. The increased hold-up achieved by the 6SRGT is commensurate with the increased power input and it is argued that the potentially extra power available should be able to give a similarly enhanced kLa. The 6SRGT agitator also gives an equivalent homogenisation performance to a standard Rushton turbine agitator of the same size at the same gassed power input. When gassed reactors are fitted with motors of sufficient power to be capable of running at full speed when ungassed, this agitator offers simple retrofitting possibilities potentially leading to considerably enhanced performance.