The performance of a fluidized bed ash cooler was studied using a cold experiment bench. The air flow rate, particle size of the solids and air distributor type are considered to be the key parameters of the operation of a fluidized bed ash cooler (FBAC). It was found that the amount of fluidizing air directly affects the conveying of ash and that they have a quadratic relationship. An acceptable particle size distribution for the solids is d(50)<450 mu m. Furthermore, the experiment reveals that the height of the weir in the FBAC does not affect the conveying of the ash flow. The influence of injected air on the transportation of ash is not significant. Optimal air nozzle dimensions are presented. (C) 2010 Elsevier B.V. All rights reserved.