To provide a method of forming a positive electrode active material with high productivity. To provide a manufacturing apparatus capable of forming a positive electrode active material with high productivity. Provided is a method of forming a positive electrode active material including lithium, a transition metal, oxygen, and fluorine. An adhesion preventing step is performed during heating of an object. Examples of the adhesion preventing step include stirring by rotating a furnace during the heating, stirring by vibrating a container containing an object during the heating, and crushing performed between the plurality of heating steps. By these manufacturing methods, a positive electrode active material having favorable distribution of an additive at the surface portion can be formed.

To provide a method of forming a positive electrode active material with high productivity. To provide a manufacturing apparatus capable of forming a positive electrode active material with high productivity. Provided is a method of forming a positive electrode active material including lithium, a transition metal, oxygen, and fluorine. An adhesion preventing step is performed during heating of an object. Examples of the adhesion preventing step include stirring by rotating a furnace during the heating, stirring by vibrating a container containing an object during the heating, and crushing performed between the plurality of heating steps. By these manufacturing methods, a positive electrode active material having favorable distribution of an additive at the surface portion can be formed.

The disclosure relates to a plant for thermal treatment of solid material to decrease the content of heavy metal elements. The plant comprises one reactor for heating the solid material, which is arranged to have both an oxidizing atmosphere and a reducing atmosphere, and the plant includes a hot gas generator, which is arranged to provide hot gas to the reactor. The disclosure also relates to a method for thermal treatment of solid material and to a method for producing fertilizer precursor.

The disclosure relates to a plant for thermal treatment of solid material to decrease the content of heavy metal elements. The plant comprises one reactor for heating the solid material, which is arranged to have both an oxidizing atmosphere and a reducing atmosphere, and the plant includes a hot gas generator, which is arranged to provide hot gas to the reactor. The disclosure also relates to a method for thermal treatment of solid material and to a method for producing fertilizer precursor.

An apparatus for thermal treatment of mineral materials may include a first combustion chamber, a second combustion chamber, and a reactor for the thermal treatment of mineral materials. The first combustion chamber is configured for burning a first fuel fed by a first fuel feed device, and the first combustion chamber and the second combustion chamber are connected via a first conduit for transferring hot gases from the first combustion chamber into the second combustion chamber. The second combustion chamber is configured for burning a second fuel that is different than the first fuel and is fed by a second fuel feed device. The second combustion chamber and the reactor are connected via a second conduit for transferring hot gases from the second combustion chamber into the reactor. The reactor has a third feed conduit for introducing a third fuel.

An apparatus for thermal treatment of mineral materials may include a first combustion chamber, a second combustion chamber, and a reactor for the thermal treatment of mineral materials. The first combustion chamber is configured for burning a first fuel fed by a first fuel feed device, and the first combustion chamber and the second combustion chamber are connected via a first conduit for transferring hot gases from the first combustion chamber into the second combustion chamber. The second combustion chamber is configured for burning a second fuel that is different than the first fuel and is fed by a second fuel feed device. The second combustion chamber and the reactor are connected via a second conduit for transferring hot gases from the second combustion chamber into the reactor. The reactor has a third feed conduit for introducing a third 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).

A method for reducing combustion temperature and/or thermal radiation within a lime kiln of a pulp production plant, which kiln is a rotary kiln having a kiln tube (1) internally covered with refractory tiles (13) and having a burner (2) supplied by fuel for heating of the rotary kiln by a flame (3). The effects are achieved by supplying calcium carbonate containing particles to the flame (3) and/or to surrounding area around the flame (3). The particles are supplied into the rotary kiln by at least one lance (9) to the upper part of the flame (3). Calcium oxide containing particles may be supplied to the rotary kiln to areas surrounding the flame (3) for reducing the thermal radiation to an area over the flame (3) and/or to the area at the side of the flame (3), where the refractory tiles (13) of the kiln are rotating downwards.

A rotary kiln includes: a heating tube; a material feeding unit disposed on a first end of the heating tube; a material collection unit disposed on a second end of the heating tube; an inner cylinder supported at the second end of the heating tube with the inner cylinder being inserted in a central portion of the heating tube; a plurality of branch tubes disposed circumferentially on an outer circumferential surface of the inner cylinder, each of the branch tubes branching from the inner cylinder and extending in an axial direction along an inner circumferential surface of the heating tube; a hot air supply tube supported to be relatively rotatable with respect to the inner cylinder with the hot air supply tube being inserted in one end of the inner cylinder that extends outside the heating tube; and a drive mechanism that rotates the heating tube.