GAS DISTRIBUTOR AND HEATER FOR SPRAY DRYING

摘要

A gas distributor and heating device for a spray dryer which includes a feed liquid atomizer (30) in a drying chamber, a gas distributor (20) for supplying a uniform flow of gas, a guide duct (40) for conveying the flow of gas from the gas distributor and to an outlet (44) providing a flow of processing or drying gas to contact liquid droplets dispersed by the atomizer. A gas heater (50) is located in the device between the gas distributor (20) and the guide duct outlet (44) to heat the gas just prior to its introduction into the spray chamber. This provides a high temperature drying gas close to the atomizer and avoids problems encountered in attempting to transfer a gas that has been heated at a location remote from the spray chamber. A guide duct in the form of an annular guide duct (40) provides an annular flow of heated gas concentric with the atomizer. A gas burner (50) extends circumferentially around the interior of the guide duct and is disposed to emit the gases of combustion in the direction of the outlet (44). The guide duct may also include a plate (46) shielding a portion of the gas flow from direct contact with the burner and the gases of combustion to provide an insulating flow of gas between the annular duct and the combustion zone.