A jet spouted fluidized bed drier is described in which the bottom half of the drier chamber comprises a first lower conical part, and the top half of the drier chamber comprises a second upper conical part surrounding a conical grid located near to the top end of the second part. The drier chamber thus comprises two conical parts connected together at their wide ends. The result of this arrangement is that the collision zone becomes a toroid with an essentially triangular cross-sectional shape defined essentially by the conical internal surface of the top part and the conical outer surface of the conical grid. This revised structural arrangement has been found to be able to process materials which either cannot be processed, or cannot be processed efficiently, with known jet spouted fluidized bed driers. Additionally, this revised structural arrangement has been found to be able to process materials more efficiently, and to a lower desired final liquid content values.