Patent ID: 8318121

Claim:
A method for processing silicon, the method comprising the following steps: providing at least one processing reactor, said at least one processing reactor comprising at least one reactor container, at least one processing column arranged inside the reactor container, and at least one heating device arranged outside the reactor container; melting silicon, which is contaminated with one or more of at least one impurity element and at least one impurity compound, by means of at least one melting device to form molten silicon; supplying the molten silicon to the at least one processing column; heating the at least one processing column to a reaction temperature by means of the at least one heating device; generating a low pressure in the reactor container by means of at least one low-pressure generation device; gassing the molten silicon, which has been supplied to the at least one processing column, with at least one gas by means of a gas supply device; evaporating said one or more of at least one impurity element and at least one impurity compound from the silicon, which is at least one of surrounded and passed through by the at least one gas, at low pressure; recovering silicon, which has evaporated during the evaporation, by means of at least one filtering device, said filtering device comprising a first filter element and at least a second filter element; and discharging the processed silicon from the processing reactor, wherein the first filter element comprises a hollow space with a bed of solid solar silicon.