Polytechnic University of Valencia Congress, 21st International Drying Symposium

Font Size: 
Determination and modelling of the particle size dependent residence time distribution in a pilot plant spray dryer
Nora Alina Ruprecht, Reinhard Kohlus

Last modified: 02-01-2019


The residence time distribution (RTD) in a pilot plant spray dryer was characterised for two kinds of air distributors (centrifugal and parallel flow) and for different atomizing air pressures. To determine the RTD - and the RTD of different particle size fractions - the particle concentration and size at the dryer outlet was measured continuously using a particle counter. Results were modelled using the Bodenstein number and the CSTR in series model. An increasing nozzle pressure leads to a decrease in mean residence time and a more narrow distribution. The influence of nozzle pressure is more pronounced than of air distributor and particle size fraction.

Keywords: Residence time distribution; Particle size; Bodenstein number modelling; Nozzle influence; Mechanism of air distribution


Full Text: PDF