Apparatus. methods. and systems for heat treatment of solid materials utilizing an indirect rotary calciner comprising one or more thermal expansion tolerant inner tubes fixed to an outer rotating shell. for example. by one or more resilient support members. The described methods of thermal treatment may be particularly utilized with cement and lime production processes and/or other heat treatment applications. such as pyrolysis.

A method for calcination includes providing a heated coarse solid particle stream with a carbon dioxide rich sorbent to a reactor having a rotatable container.

An apparatus for producing cement clinker, comprising a kiln for calcining raw materials to form cement clinker, comprising a preheating stage for preheating the raw materials in a counter-flow to kiln off-gases, comprising a clinker cooler for cooling the cement clinker, comprising a denoxing stage for denoxing kiln off-gases, comprising a heat exchanger for heating the kiln off-gases upstream of the denoxing stage by heat exchange with a heat exchange medium, comprising at least one further heat exchanger for heating the heat exchange medium by heat exchange with kiln off-gases or exhaust air of the clinker cooler, wherein the heat exchanger is connected to the further heat exchanger via a line for the heat exchange medium, wherein a hot gas filter is arranged in the flow direction upstream of the further heat exchanger.

The invention relates to a method and a system for producing cement clinker from raw cement mixture, wherein one part of the raw cement mixture is preheated in a calciner preheater, and the other part of the raw cement mixture is preheated in an oven preheater, the preheated raw cement mixture is pre-calcined in a calciner which is operated according to the oxyfuel method, the pre-calcined raw cement mixture is fired in an oven, the fired raw cement mixture is cooled in a cooler, the calciner preheater is operated using exhaust gases of the calciner, the oven preheater is operated using exhaust gases of the oven, an entrained flow reactor is used as the calciner, a part of the calciner exhaust gas being recirculated to the calciner after being used in the calciner preheater, and the oven exhaust gas undergoes a post-combustion CO.sub.2 separation.

A method for calcination of a carbon dioxide rich sorbent (containing CaCO.sub.3) includes combusting in a furnace a fuel with an oxidizer, supplying heat transfer (HT) solids into the furnace and heating them, transferring the HT solid particles from the furnace to a reactor having a rotatable container, supplying a carbon dioxide rich solid sorbent (containing CaCO.sub.3) into the rotatable container, rotating the rotatable container for mixing the solid particles and the carbon dioxide rich solid sorbent for transferring heat from the solid particles to the carbon dioxide rich solid sorbent and generating carbon dioxide and carbon dioxide lean solid sorbent (mainly CaO), discharging the carbon dioxide and the carbon dioxide lean solid sorbent from the rotatable container and the subsequent classification of the HT solids from the lean sorbent.

The device for pre-heating cement raw meal for the cement clinker production comprises at least one heat exchanger line for charging cement raw meal in countercurrent flow to the hot gases drawn through the heat exchanger line and a supporting structure (19) for the at least one heat exchanger line, wherein the heat exchanger line comprises a plurality of heat exchangers (8, 9, 10) which are interconnected and through which flow can pass consecutively. The supporting structure (19) comprises stands (20) which jointly form a triangular outline (21) and serve to transfer load into at least one foundation.

A process and an apparatus are disclosed for improved recovery of metal from hot and cold dross, wherein a dross-treating furnace is provided with a filling material with good capacity to store heat. This filling material is preheated to a desired temperature by injection of an oxidizing gas to burn non-recoverable metal remaining in the filling material after tapping of the recoverable metal contained in the dross and discharging of the treatment residue. When dross is treated in such furnace, the heat emanating by conduction from the filling material is sufficient to melt and separate the recoverable metal contained in the dross, without addition of an external heat source, such as fuel or gas burners, plasma torches or electric arcs and without use of any salt fluxes. Furthermore, the recovered metal being in the molten state can be fed to the molten metal holding furnace without cooling the melt; in addition, the non-use of fluxing salt for the treatment means that the non-contaminated residue can be used as a cover for the electrolytic cells in the case of aluminum. In the case of zinc dross, the residue is a valuable zinc oxide by-product very low in contaminants.

A non-transitory computer readable media can cause the imaging analysis computer to: obtain a 3D model of a preheater level of the preheater; obtain at least one infrared image of a fixed field of view of the preheater level of the preheater; analyze all pixels in the fixed field of view of the at least one infrared image for each pixel temperature; generate a 2D temperature model of the preheater level; overlaying the 2D temperature model over the 3D model to generate a virtual 3D preheater level temperature model; and provide a visual representation of the virtual 3D preheater level temperature model.

The invention provides a powder-gas heat exchanger for exchanging heat between a powder stream and a gas stream in counter-current flow comprising a powder stream mass flow rate substantially equal to a gas stream mass flow rate in a vertical shaft heat exchanger. A hot gas stream may be adapted for use in heating a cool solids stream, or a cool gas stream may be adapted for use in cooling a hot solids stream.

A process and an apparatus are disclosed for improved recovery of metal from hot and cold dross, wherein a dross-treating furnace is provided with a filling material with capacity to store heat. This filling material is preheated to a desired temperature by injection of an oxidizing gas to burn non-recoverable metal remaining in the filling material after tapping of the recoverable metal contained in the dross and discharging of the treatment residue. When dross is treated in such furnace, the heat emanating by conduction from the filling material is sufficient to melt and separate the recoverable metal contained in the dross, without addition of an external heat source, such as fuel or gas burners, plasma torches or electric arcs and without use of any salt fluxes. Furthermore, the recovered metal being in the molten state can be fed to the molten metal holding furnace without cooling the melt.