Abstract: A sludge drying apparatus (10) including a housing through which air is recirculated wherein makeup air forms an air curtain assuring recirculation of heated air. The housing (12) includes a receiving station (14) in which sludge (20) is deposited on a conveyor belt (18). The conveyor belt (18) moves the sludge (20) to a drying station (16) where infrared heaters (42) radiate infrared heat on the sludge. Air for drying the sludge circulates from a fan plenum (28) to an air supply plenum (24). Air from the air supply plenum (24) passes across the face of the infrared heaters (42), and is directed downwardly toward the sludge (20) in a belt passageway (30). Air is returned through a return air plenum (26) located below the belt passageway (30). Part of the air received by the return air plenum (26) is ported directly from the belt passageway (30) to the return air plenum (26).

Abstract: A method and apparatus for treating sludge from a paint spray booth operation. The sludge from the spray booth is deposited onto a porous belt of a conveyor system to allow the water to pass through the belt where it is collected for discharge from the apparatus. The remaining residue is passed over a vacuum device positioned beneath the belt and is then carried by the belt through an oven comprising a series of infrared thermal reactors arranged in serial fashion over the belt. The sludge is passed continuously beneath the infrared reactors and is dried thereby so that the sludge leaving the apparatus is in a dried particulate form which may be readily disposed of and/or solid. Convection air is recirculated through the apparatus to preheat the incoming sludge, remove smoke and other contaminants from the oven, and provide the desired pressure condition within the oven to optimize the efficiency of the thermal reactors.

Abstract: A method and apparatus for subjecting articles to surface treatment of a sequence of solutions utilizing a plurality of process tanks and a plurality of supply tanks, each supply tank containing one of the solutions utilized in the process. The process tanks and supply tanks are interconnected by conduit means which include a series of valves which may be activated and deactivated for routing the solution to and from any of the selected tanks. The valves are automatically activated and deactivated by a programmable control which allows for articles introduced into each of the process tanks to be subjected to each of the solutions in a programmed sequence.