The most important requirements of gas-solid two phase flow feeding are a very uniform mass flow of fine particles and providing a homogeneous dispersed cloud of them. In this study, a screw-brush feeding device has been developed to feed fine zinc oxide powders and to achieve a homogenous gas-particle two phase flow by a minimum gas flow rate. The results of these experiments indicated that the performance of this feeding system without gas flow was better than a screw feeder alone, to stabilize the feeding of fine ZnO powder at low flow rates. Moreover, the results of experimental micrographs showed that the screw-brush system with a minimal amount of gas flow rate is able to reduce the mean aggregate size of the particle size distribution and could provide a homogeneous gas-particle flow. (C) 2014 Published by Elsevier B. V. on behalf of The Society of Powder Technology Japan. All rights reserved.