Dryer for lactose and high lactose products

A system comprising:

• a plurality of evaporators connected in series, wherein the evaporators output a concentrated wet lactose stream with a total solids content of about 70 wt % to about 92 wt %;
• a crystallization system that inputs the concentrated wet lactose stream and outputs an at least partially crystallized wet lactose stream comprising crystallized wet lactose, wherein the at least partially crystallized wet lactose stream is input into a drying and finishing system, the drying and finishing system comprising:
• a disperser that breaks up agglomerated particulates of crystallized wet lactose in the at least partially crystallized wet lactose stream to form a dispersed wet lactose stream;
• a back-mixed partial drying zone that at least partially dries the dispersed wet lactose stream by recirculating a partially dried lactose stream with the dispersed wet lactose stream;
• and
• a plug-flow secondary drying zone that dries the partially dried lactose stream to generate a substantially dried lactose stream with a free moisture content of about 0.0% by weight to about 1.0% by weight.