Abstract: A filter vessel for removing metal particles from exhaust, comprising a casing defining an internal chamber adapted to receive a flow of gas travelling along a flow direction; an electrostatic grid disposed in the internal chamber in intersecting relation to the flow direction, the electrostatic grid adapted to electrostatically charge metal particles in the flow of gas; a first electromagnet disposed on the casing in a downstream location along the flow direction relative to the electrostatic grid, the first electromagnet adapted to attract the electrostatically charged metal particles; a second electromagnet disposed on the casing in a downstream location along the flow direction relative to the first electromagnet, the second electromagnet adapted to attract the electrostatically charged metal particles; a controller configured to control the energization of the first and second electromagnets; and a metal particle collector for collecting electrostatically charged metal particles attracted by the first an