A horizontal box dryer as often applied in the egg
industry was used for the experiments (Fig 1). The
liquid egg product is conveyed through a high-pressure
nozzle by a pump and sprayed horizontally into the
drying chamber. The dimensions of the nozzle can be
adapted to different pressures and flow rates. The main
part of the dried powder falls down to a conveyor-belt at
the bottom of the chamber. Smaller particles can be
drawn from a textile filter unit. The maximum
evaporation rate of the dryer is 50kg water h1.
A 32 experimental design matrix was used for the
drying parameters, where the inlet air temperature and
the nozzle pressure were varied at three levels as shown
in Table 1.