Abstract: In rotary tubes (1), an insert (4) which expands under the influence of heat can be moved in the radical direction in a cold outer casing (3) by means of an end plate (19) but is fixed in the axial direction, whereas other plates (20, 21) of the insert (4) have cogs (27) which are guided in sliding grooves (16) parallel to the axis due to the thermal expansion, each plate (20, 21) being provided with at least three cogs (24) and three sliding grooves (16) over its periphery.

Abstract: A process for the calcining of limestone or hydrated lime by thermal treatment thereof with hot gases in a rotary kiln through which the kiln atmosphere and the charge are countercurrently passed, which kiln is fed with solid carbonaceous fuel, is described. The invention resides in introducing an oxygen-containing gas into a horizontal region across the rotary kiln defined by a point along the length of the kiln where ignitable particles of said solid fuel first appear and a second point along the length of said rotary kiln which is spaced from the charging end of said kiln not more than 50% of the length thereof. The oxygen-containing gases are injected through nozzle blocks in said rotary kiln, and oxygen-containing gas is introduced into the free space of said kiln.

Abstract: Apparatus and process for treating wood and other fibrous materials within a hermetically sealed, heat insulated chamber comprising means for applying a predetermined mechanical pressure to said fibrous materials, means for controlling the conditions within said chamber whereby steam is generated in the center of said fibrous materials, and means for subsequently removing said steam; means are additionally provided for staining, finishing, fireproofing, laminating, forming, shaping, and increasing the density and tensile strength of said fibrous materials.

Abstract: A method for treating whole logs to prevent them from splitting as they are dried to a desired moisture content. Whole green logs are placed in a pressure vessel which is sealed. Preferably the logs are debarked before they are placed in the vessel, but they may be debarked after their removal therefrom. Steam is thereafter injected into the vessel until the wood throughout the logs has reached a temperature within the range of about 190.degree.-240.degree. F., while condensed water and other fluids from the wood are drained from the vessel. Subsequently the pressure in the vessel is released at a rate slow enough that no significant collapse of the wood within the logs occurs, and when the logs are cool enough to handle they are removed, debarked if necessary, and dried in a room whose relative humidity is maintained not less than about 45% until the logs have reached a predetermined moisture content.

Abstract: A dry wood material free from seasoning check is produced with good yield from undried wood material with water content of 50 to 200% by drying the undried wood material while controlling the rate of evaporation of water from the undried wood material by providing on its surface a barrier layer having a water vapor permeability in the specific range from 10 to 100 g/m.sup.2.day.

Abstract: An emission control system and a method of treating a gaseous effluent is disclosed. The system is particularly suited for treating gaseous effluents from a veneer dryer prior to venting to the atmosphere. The system comprises means for temperature adjustment, flow control, and catalytic oxidation of the effluent.

Abstract: An apparatus for drying particulate material includes an elongate housing having a chamber therein. A drum is positioned in the housing and has opposite ends thereof extending through open ends of the housing. The drum is mounted for rotation about its longitudinal axis. The exterior surface of the drum and the interior surface of the housing are spaced apart and form an annular space adapted for flow of heating medium therealong. An inlet opens into the annular space and is directed for introducing heating medium in a generally tangential direction relative to the annular space such that the heating medium flows in a generally vortex manner along the length of the annular space to the outlet. A tube is positioned in the drum and extends along a major portion of the length of the drum. The tube is in flow communication with the annular space for receiving heating medium therefrom.

Abstract: A timber drying plant has a drying chamber through which air may be circulated by a fan in a circuit which includes a refrigerating unit. The refrigerant fluid circuit of the unit includes a dehumidification evaporator for outlet air and a condenser in the recycle air flow for returning to the latter least part of the heat extracted by the evaporator. The refrigerant fluid circuit also includes an auxiliary evaporator with control valve means whereby the auxiliary evaporator can be inserted in said fluid circuit so that the refrigerating unit operates as a heat pump absorbing heat from the external atmosphere through the auxiliary evaporator. A supplementary evaporator may also be included in the refrigerating unit and is connectable in parallel with the auxiliary evaporator to increase the heat pump effect. In another position of the control valve means the auxiliary evaporator acts as a condenser in circuit with the dehumidification evaporator to reduce the heating of the recycled air.

Abstract: Apparatus for dehydrating organic waste material in a rotary oven. The oven is within an insulated chamber and the oven is heated by a burner. The waste gases from the oven are recycled and burnt in the burner. The dried product is usable for soil enrichment and for feeding to animals.

Abstract: Lumber within a kiln is subjected to a multi-step process including initial dehumidification drying to a moisture content of approximately 12 to 20 percent followed by drying at a substantially higher temperature without dehumidification. The higher temperature drying step is continued until a moisture content of approximately 6 percent is reached, after which high humidity conditions are preferably introduced into the kiln for equalization and/or conditioning of the lumber.

Abstract: In a rotary heat exchanger, two groups of tubes are concentrically arranged about a drive shaft and the tubes have ports at their ends which are in communication with inlet and discharge chambers to which respective streams of gas are delivered so that two separate streams of gas may be circulated through the tubes. A solid granular material is supplied into the tubes of one group at one end and, near the other end, the tubes of the first and second groups are interconnected for passing the material from one group to the other.

Abstract: This invention relates to a process for introducing holes or straight or circular slots approximately normal to the surface in the vicinity of the surface of round timber and to an approximately predetermined depth for the purpose of facilitating the penetration of impregnating means into the surface zones of the timber to better protect against chemical and biological attacks.

Abstract: Air is vented from steam-charged heating pipes of a tubular rotary dryer via connector pipes and a collecting pipe which is disposed circumferentially around the dryer drum. Holding blocks provided with inwardly-biased rollers support the collecting pipe for longitudinal movement on the exterior wall of the dryer drum.

Abstract: Apparatus and process for treating wood and other fibrous materials within a hermetically sealed, heat insulated chamber comprising means for applying a predetermined mechanical pressure to said fibrous materials, means for controlling the conditions within said chamber whereby steam is generated in the center of said fibrous materials, and means for subsequently removing said steam; means are additionally provided for staining, finishing, fireproofing, laminating, forming, shaping, and increasing the density and tensile strength of said fibrous materials.

Abstract: A rotating drum type muller is described for initial conditioning of mined tar sands by the hot water method for separation of bitumen from the sands wherein ablation of mined tar sand lumps into pulp is effected through the addition of hot water, steam and caustic.

Abstract: A rotating drum type muller is described for initial conditioning of mined tar sands by the hot water method for separation of bitumen from the sands wherein ablation of mined tar sand lumps into pulp is effected through the addition of hot water, steam and caustic.