In the disclosed solution sand to be cleaned is thermally cleaned by rotating the sand being cleaned in a large oven (1) by rotating the oven (1). Before cleaning, the sand may be pre-processed by crushing any lumps and cleaning the sand fraction by magnetic separation. Preprocessed sand to be cleaned and heat energy are fed (5) into the rotating oven. The oven (1) is set slightly inclined so that a second end of the oven (1) is lower than a first end. The inclination and rotating speed of the oven (1) as well as the feed amount of sand are adjusted, whereby the advancing speed of the sand may be adjusted, as well as the ratio of the sand being cleaned to the volume of the oven (1) kept as desired. The temperature of the oven (1) is monitored at the coldest area of the oven, which is substantially at the second end of the oven. The temperature of the oven (1) is adjusted by adjusting the amount of heat energy fed in. By means of temperature monitoring and knowing the advancing speed of the sand, it is also possible to determine the average temperature of the sand and adjust it as desired by adjusting the supplied heat energy. Finally, the cleaned sand is let run (12) from the second end of the oven (1).

In the disclosed solution sand to be cleaned is thermally cleaned by rotating the sand being cleaned in a large oven (1) by rotating the oven (1). Before cleaning, the sand may be pre-processed by crushing any lumps and cleaning the sand fraction by magnetic separation. Preprocessed sand to be cleaned and heat energy are fed (5) into the rotating oven. The oven (1) is set slightly inclined so that a second end of the oven (1) is lower than a first end. The inclination and rotating speed of the oven (1) as well as the feed amount of sand are adjusted, whereby the advancing speed of the sand may be adjusted, as well as the ratio of the sand being cleaned to the volume of the oven (1) kept as desired. The temperature of the oven (1) is monitored at the coldest area of the oven, which is substantially at the second end of the oven. The temperature of the oven (1) is adjusted by adjusting the amount of heat energy fed in. By means of temperature monitoring and knowing the advancing speed of the sand, it is also possible to determine the average temperature of the sand and adjust it as desired by adjusting the supplied heat energy. Finally, the cleaned sand is let run (12) from the second end of the oven (1).

An active material recovery apparatus capable of easily recovering an electrode active material from an electrode scrap in its intrinsic shape and a positive electrode active material reuse method using the active material recovery apparatus are provided. The active material recovery apparatus which is a rotary firing apparatus comprising a rod in a screw type therein includes a heat treatment bath and a screening wall arranged in a line along an axis of the rod, wherein the heat treatment bath constitutes a heating zone, and the screening wall constitutes a cooling zone; and an exhaust injection and degassing system, wherein the heat treatment bath removes a binder and a conductive material in an active material layer by performing heat treatment on an electrode scrap comprising the active material layer on a current collector in an air while rotating the electrode scrap around the axis of the rod and separates the current collector from the active material layer, and an active material in the active material layer passes through the screening wall and is recovered as an active material in powder form, and the current collector that does not pass through the screening wall is recovered separately.

Disclosed is a clinker production plant including: a preheating unit; a calcination unit; a kiln; and a cooler. The calcination assembly includes a calcination reactor for calcination by combustion of a solid so-called alternative fuel. The calcination reactor is arranged such that at least part of the combustion fumes from the kiln pass partly through the calcination reactor before entering the preheating unit, and a tertiary gas flow including air leaving the cooler passing at least in part through the calcination reactor before entering the preheating unit. The calcination reactor includes a system for controlling the residence time of the alternative solid fuel.

In the disclosed solution sand to be cleaned is thermally cleaned by rotating the sand being cleaned in a large oven (1) by rotating the oven (1). Before cleaning, the sand may be pre-processed by crushing any lumps and cleaning the sand fraction by magnetic separation. Preprocessed sand to be cleaned and heat energy are fed (5) into the rotating oven. The oven (1) is set slightly inclined so that a second end of the oven (1) is lower than a first end. The inclination and rotating speed of the oven (1) as well as the feed amount of sand are adjusted, whereby the advancing speed of the sand may be adjusted, as well as the ratio of the sand being cleaned to the volume of the oven (1) kept as desired. The temperature of the oven (1) is monitored at the coldest area of the oven, which is substantially at the second end of the oven. The temperature of the oven (1) is adjusted by adjusting the amount of heat energy fed in. By means of temperature monitoring and knowing the advancing speed of the sand, it is also possible to determine the average temperature of the sand and adjust it as desired by adjusting the supplied heat energy. Finally, the cleaned sand is let run (12) from the second end of the oven (1).

In the disclosed solution sand to be cleaned is thermally cleaned by rotating the sand being cleaned in a large oven (1) by rotating the oven (1). Before cleaning, the sand may be pre-processed by crushing any lumps and cleaning the sand fraction by magnetic separation. Preprocessed sand to be cleaned and heat energy are fed (5) into the rotating oven. The oven (1) is set slightly inclined so that a second end of the oven (1) is lower than a first end. The inclination and rotating speed of the oven (1) as well as the feed amount of sand are adjusted, whereby the advancing speed of the sand may be adjusted, as well as the ratio of the sand being cleaned to the volume of the oven (1) kept as desired. The temperature of the oven (1) is monitored at the coldest area of the oven, which is substantially at the second end of the oven. The temperature of the oven (1) is adjusted by adjusting the amount of heat energy fed in. By means of temperature monitoring and knowing the advancing speed of the sand, it is also possible to determine the average temperature of the sand and adjust it as desired by adjusting the supplied heat energy. Finally, the cleaned sand is let run (12) from the second end of the oven (1).

The device for drying or heating and cooling bulk material in accordance with the invention consists of a rotatable drum comprising means for receiving the bulk material in a first region and means for discharging the bulk material from a second region, wherein a central region is arranged between the first and second regions, said central region consisting of an annular structure with a first and a second diaphragm with central diaphragm apertures each, which form substantially two diaphragm planes parallel to each other, and comprise a plurality of transport channels closed toward the central region for transporting the bulk material from the first region to the second region of the rotatable drum through the central region, wherein the transport channels extend from the first to the second diaphragms at a non-90 angle relative to the two diaphragm planes.

The device for drying or heating and cooling bulk material in accordance with the invention consists of a rotatable drum comprising means for receiving the bulk material in a first region and means for discharging the bulk material from a second region, wherein a central region is arranged between the first and second regions, said central region consisting of an annular structure with a first and a second diaphragm with central diaphragm apertures each, which form substantially two diaphragm planes parallel to each other, and comprise a plurality of transport channels closed toward the central region for transporting the bulk material from the first region to the second region of the rotatable drum through the central region, wherein the transport channels extend from the first to the second diaphragms at a non-90 angle relative to the two diaphragm planes.

An industrial furnace and a method for roasting or regenerating spent petroleum catalysts. The furnace particularly includes a device to set the catalysts in motion along the bottom of the furnace to cause the catalysts to circulate from the inlet towards the outlet of the furnace; a first zone decarbonizing the spent catalysts to obtain decarbonized catalysts, followed by: a second zone including a plurality of oxygen feed devices distributed along the length of the second zone and placing the decarbonized catalysts in contact with the oxygen feed, the second zone desulfurizing the decarbonized catalysts to obtain roasted or regenerated catalysts.

An industrial furnace and a method for roasting or regenerating spent petroleum catalysts. The furnace particularly includes a device to set the catalysts in motion along the bottom of the furnace to cause the catalysts to circulate from the inlet towards the outlet of the furnace; a first zone decarbonizing the spent catalysts to obtain decarbonized catalysts, followed by: a second zone including a plurality of oxygen feed devices distributed along the length of the second zone and placing the decarbonized catalysts in contact with the oxygen feed, the second zone desulfurizing the decarbonized catalysts to obtain roasted or regenerated catalysts.