The present invention provides a fine silicon powder and the like including fine silicon particles having a microscopically measured particle diameter of 1 μm or more and an average circularity determined in accordance with Formula (1) of 0.93 or more, in which an average particle diameter based on volume, which is measured by a laser diffraction scattering method, is in a range of 0.8 μm or more and 8.0 μm or less, an average particle diameter based on number, which is measured by the laser diffraction scattering method, is in a range of 0.100 μm or more and 0.150 μm or less, and a specific surface area, which is measured by a BET method, is in a range of 4.0 m.sup.2/g or more and 10 m.sup.2/g or less. Circularity=(4×π×projected area of particle).sup.1/2/peripheral length of particle (1).

The present invention provides a fine silicon powder and the like including fine silicon particles having a microscopically measured particle diameter of 1 μm or more and an average circularity determined in accordance with Formula (1) of 0.93 or more, in which an average particle diameter based on volume, which is measured by a laser diffraction scattering method, is in a range of 0.8 μm or more and 8.0 μm or less, an average particle diameter based on number, which is measured by the laser diffraction scattering method, is in a range of 0.100 μm or more and 0.150 μm or less, and a specific surface area, which is measured by a BET method, is in a range of 4.0 m.sup.2/g or more and 10 m.sup.2/g or less. Circularity=(4×π×projected area of particle).sup.1/2/peripheral length of particle (1).

One compound (100) according to the present invention contains silicon fine particles having a capability of generating hydrogen or aggregates of the silicon fine particles. The compound that contains the silicon fine particles or the aggregates having a capability of generating hydrogen is capable of generating hydrogen in the body of, for example, an animal that has ingested the compound. For a plant, the compound can be disposed or charged into, for example, moisture (water-containing liquid) or fertilizer to be provided to the plant, to supply the plant with hydrogen generated from the compound.

One compound (100) according to the present invention contains silicon fine particles having a capability of generating hydrogen or aggregates of the silicon fine particles. The compound that contains the silicon fine particles or the aggregates having a capability of generating hydrogen is capable of generating hydrogen in the body of, for example, an animal that has ingested the compound. For a plant, the compound can be disposed or charged into, for example, moisture (water-containing liquid) or fertilizer to be provided to the plant, to supply the plant with hydrogen generated from the compound.

Methods of forming a composite material film can include providing a mixture comprising a precursor and silane-treated silicon particles. The methods can also include pyrolysing the mixture to convert the precursor into one or more carbon phases to form the composite material film with the silicon particles distributed throughout the composite material film.

Metallurgical silicon containing impurities of carbon and/or carbon-containing compounds is classified and subsequently used selectively for chlorosilane production. The process comprises the steps of: a) determining the free carbon proportion which reacts with oxygen up to a temperature of 700° C., b) directing metallurgical silicon in which the free carbon proportion is ≤150 ppmw to a process for producing chlorosilanes and/or directing metallurgical silicon in which the free carbon proportion is >150 ppmw to a process for producing methylchlorosilanes. As a result of the process, metallurgical silicon having a total carbon content of up to 2500 ppmw can be used for producing chlorosilanes.

A method for producing a polycrystalline silicon rod includes: while energizing a core wire formed of silicon, supplying a polycrystalline silicon deposition raw material gas into a reactor so as to perform gas phase growth of polycrystalline silicon on a surface of the core wire, in which during a period from a completion of cleaning of the surface of the above core wire to an installation of the core wire in the reactor, the silicon core wire is placed in an atmosphere adjusted to a cleanliness of Class 4 to Class 6 as defined in ISO 14644-1. With this method, it is possible to obtain a polycrystalline silicon rod which has a total metal concentration of iron and nickel of 40 pptw or less in terms of elements in a region within 2 mm from an interface between the core wire and polycrystalline silicon deposited on the surface of the core wire.

A method for producing a polycrystalline silicon rod includes: while energizing a core wire formed of silicon, supplying a polycrystalline silicon deposition raw material gas into a reactor so as to perform gas phase growth of polycrystalline silicon on a surface of the core wire, in which during a period from a completion of cleaning of the surface of the above core wire to an installation of the core wire in the reactor, the silicon core wire is placed in an atmosphere adjusted to a cleanliness of Class 4 to Class 6 as defined in ISO 14644-1. With this method, it is possible to obtain a polycrystalline silicon rod which has a total metal concentration of iron and nickel of 40 pptw or less in terms of elements in a region within 2 mm from an interface between the core wire and polycrystalline silicon deposited on the surface of the core wire.

The present disclosure provides a system and method for granulating and molding silicon liquid. The system includes a silicon liquid transferring device, wherein cooling system and a lifting system matching with the cooling system are provided below the silicon liquid transferring device. The silicon liquid transferring device transfers smelted silicon liquid to a position above the cooling system, uniformly pours the silicon liquid into the cooling system according a set flow to enable the silicon liquid to be solidified into silicon pellets, and then the molded silicon pellets are extracted by the lifting system, solving the problem in the prior art of irregular molding and inconsistent size of silicon blocks caused by pouring. A container bottom and a diversion pipe are set to be of detachable structures, and can be quickly disassembled and assembled as vulnerable parts without affecting the production.

The present disclosure provides a system and method for granulating and molding silicon liquid. The system includes a silicon liquid transferring device, wherein cooling system and a lifting system matching with the cooling system are provided below the silicon liquid transferring device. The silicon liquid transferring device transfers smelted silicon liquid to a position above the cooling system, uniformly pours the silicon liquid into the cooling system according a set flow to enable the silicon liquid to be solidified into silicon pellets, and then the molded silicon pellets are extracted by the lifting system, solving the problem in the prior art of irregular molding and inconsistent size of silicon blocks caused by pouring. A container bottom and a diversion pipe are set to be of detachable structures, and can be quickly disassembled and assembled as vulnerable parts without affecting the production.