Using Particle Residence Time Distributions as an Experimental Approach for Evaluating the Performance of Different Designs for a Pilot-Scale Spray Dryer

The performances of four different designs for a pilot-scale spray dryer have been evaluated and compared based on experimentally measured particle residence time distributions (RTD), recovery rates physical properties spray-dried fresh skim milk. RTDs using dye pulse injection method, the measurements fitted to models continuous stirred-tank reactors in series (CSTR-TIS) quantitative performance evaluation comparison. Conical drying chambers box connection design used latest reduce amount wall deposition provide smoother gas flow pattern. particle-to-gas mean ratio is significantly closer unity (1.6 s/s 1.0 s/s) with earlier (2.6 1.5 s/s). has wider spread RTD (n = 5–8) 13–18), which may be linked recirculation zone connection. Although RTD, conical shown promising results cylindrical chamber terms overall behaviours.