Apparatus for additively manufacturing three-dimensional objects

A method of filtering charged particles from a stream of process gas circulating through a system for additively-manufacturing three-dimensional objects, the method comprising:

• circulating the stream of process gas through one or more streaming paths, the stream of process gas generated by one or more stream generating units, and the one or more streaming paths respectively comprising a process chamber inlet and a process chamber outlet;
• flowing the stream of process gas through a process chamber of respective ones of a plurality of apparatuses configured to additively manufacture three-dimensional objects by successive layerwise selective irradiation and consolidation of layers of a powdered build material;
• accumulating charged particles in the stream of process gas flowing through the process chamber;
• removing charged particles with the stream of process gas flowing through the process chamber;
• flowing the stream of process gas having accumulated charged particles through one or more filter units disposed along respective ones of the one or more streaming paths, the one or more filter units thereby separating the charged particles from the stream of process gas;
• receiving charged particles having been separated from the stream of process gas in one or more particle reception chambers respectively coupled to the one or more filter units by one or more particle guides;
• supplying a passivating material from a passivation unit to the one or more particle guides and/or the one or more particle reception chambers;
• sealing the one or more particle reception chambers via a valve;
• and
• moving, with a driving unit, the one or more particle reception chambers.