Drying sludge or fodder with process gas - produced by a burner and partly recycled

摘要

A prod. such as sludge or green fodder is passed through a vessel with heated process gas to dry it. The process gas is made in a furnace by burning fuel in air. The gas saves the dryer with the prod. and is sepd. from it. Part of the gas is recycled to the furnace. It is added back at a point at which the burning gas reached a considerable degree of stabilisation. The recycle gas cools the furnace and reduces maintainance costs. Soot formation is minimised. The thermal efficiency of the system is high.