A continuous heating furnace including an inlet, a heating zone, a cooling zone and an outlet in this order, for carrying out a heat treatment while conveying at least one workpiece from the inlet to the outlet, wherein the cooling zone is configured such that an ambient gas for direct cooling of the workpiece can flow into the cooling zone from the outlet; the cooling zone includes a plurality of indirect coolers arranged in parallel in the conveying direction of the workpiece, each of the indirect coolers having at least one regulator for independently adjusting a cooling power; and the cooling zone includes one or more residual heat outlets for discharging a residual heat gas in the cooling zone.

A method and an apparatus method for producing direct reduced iron (DRI) from iron ore using biomass as a source of reductant and as a heating source of the iron ore and electromagnetic energy as a further heating source in a furnace having multiple zones. The zones include a preheat zone and a reduction zone between an inlet for briquettes of iron ore and biomass and an outlet for direct reduced iron. The method includes counter-current movement of (a) briquettes of iron ore and biomass in a direction from the inlet to the outlet and (b) combustible gases in an opposite direction in the furnace.

A method and an apparatus for recycling a significant amount of heat within a linear hearth furnace by means of an endless conveyor that transports briquettes through the furnace from an inlet (briquette feed) end to an outlet (DRI discharge) end and then returns to the inlet end and transfers a significant amount of heat from the outlet end to the inlet end of the furnace.

A continuous heating furnace including an inlet, a heating zone, a cooling zone and an outlet in this order, for carrying out a heat treatment while conveying at least one workpiece from the inlet to the outlet, wherein the cooling zone is configured such that an ambient gas for direct cooling of the workpiece can flow into the cooling zone from the outlet; the cooling zone includes a plurality of indirect coolers arranged in parallel in the conveying direction of the workpiece, each of the indirect coolers having at least one regulator for independently adjusting a cooling power; and the cooling zone includes one or more residual heat outlets for discharging a residual heat gas in the cooling zone.

A sublimation furnace has a first endless conveyor belt extending along a first axis through the furnace, with a chamber extending above and along that first conveyor belt. Vacuum trays placed on the first belt have products abutting sublimation images to be transferred to the product as the trays pass through the furnace. The furnace has a first sidewall with a slot extending along the sidewall and along the first conveyor belt. A second endless conveyor belt extends along but offset from the first axis. A plurality of vacuum pumps are connected to the second conveyor belt and move with that belt, with each pump connected by a hose passing through the slot during use of the furnace to a different vacuum tray on the first conveyor in order to evacuate the vacuum trays and press the images against the product for sublimation transfer.

A sublimation furnace has a first endless conveyor belt extending along a first axis through the furnace, with a chamber extending above and along that first conveyor belt. Vacuum trays placed on the first belt have products abutting sublimation images to be transferred to the product as the trays pass through the furnace. The furnace has a first sidewall with a slot extending along the sidewall and along the first conveyor belt. A second endless conveyor belt extends along but offset from the first axis. A plurality of vacuum pumps are connected to the second conveyor belt and move with that belt, with each pump connected by a hose passing through the slot during use of the furnace to a different vacuum tray on the first conveyor in order to evacuate the vacuum trays and press the images against the product for sublimation transfer.