In this work, an innovative application of vacuum membrane distillation (VMD) was studied. In particular, the potential of the process for the dehydration of an aqueous solution containing solid polystryrene microparticles (7 mu m) was investigated and the unit was named vacuum membrane dryer (VMDr). The main objective was to obtain a concentrate with a solid content higher than 95 wt%, together with a permeate particle-free. For this purpose, five different membrane module designs, with both flat and fiber commercial membranes (polypropylene, 0.2 mu m), were designed, tested and compared. In all cases, the produced permeate did not contain any solid microparticle, whereas only for two configurations it was possible to reach the desired target, with a final solid content in the feed up to 98 wt%. (C) 2014 Elsevier B.V. All rights reserved.