Abstract: A method and apparatus for biologically treating refuse or thickened sludge to form compost utilizes a vertical cylindrical chamber havng an upper inlet aperture and a lower outlet aperture. An axial shaft located within the chamber has mounted thereon a plurality of radial arms each having a plurality of gas distributor blades. Sets of arms are spaced axially along the shaft. The chamber wall is formed in part by a plurality of hollow, cylindrical exhaust ducts concentrically arranged and extending differing distances along the chamber side. The end of each duct is flared to form an exhaust aperture which extends around the entire chamber. Material to be treated enters the chamber at the upper inlet and fills the chamber. The rotating radial arms and blades distribute a treating gas mixture to the material, which gas is exhausted by the annular exhaust apertures and exhaust ducts.

Abstract: Continuous flow grain drying apparatus having an upper, foraminous drying enclosure into which grain to be dried is introduced and which communicates with a lower, foraminous cooling enclosure. A first enclosed, foraminous duct in the upper enclosure defines therewith a first pair of passages which divide the downward flow of grain into two separate parallel streams, a blower and burner combination communicating with the first duct causing outward flow of heated air simultaneously through the first passages. A second, enclosed, foraminous duct is provided in the lower enclosure defining therewith a second pair of passages and a divider connects the first and second ducts and extends through the open ends of the upper and lower enclosures thereby coupling respective ones of the first and second passages so that the two streams respectively continue separate, downward, parallel flow through the second passages.

Abstract: A grain dryer is disclosed in which a blower forces air past a burner and then through a duct into a bin made of oppositely curved columns of grain defining between them and an end wall a plenum chamber for drying the grain in the bin. The invention resides in the use of a plurality of spaced baffles of particular configuration designed to take a stream of air of non-uniform pressure and temperature over a cross section of the stream, and transforming said stream into a stream in the plenum chamber of substantially uniform pressure and temperature over any cross section thereof, said stream, if desired, having a predetermined temperature gradient lengthwise of the bin which compensates for a lengthwise dryness gradient in the grain in the bin.