Abstract: The present disclosure refers to a method for regenerating a filter adapted to remove particulate material from a gas. The disclosed method comprises at least producing at least one electric arc discharge pulse, the at least one electric arc discharge pulse being adapted to generate at least one pressure wave so that the particulate material is being dislodged from the filter. In addition, the disclosure refers to a filter regenerating arrangement and a diesel particulate filter.

Abstract: An apparatus for removing particulates from a gas stream is described comprising a filter through which gas may be caused to flow, at least one first electrode for producing an atmospheric glow discharge located near to but spaced apart from the filter, and at least one second counter electrode, the electrodes being connected to an AC voltage supply generating an AC voltage in a frequency within the range of 1 kHz to 200 kHz. A method of removal of particulates from a gas stream comprising causing the gas to flow through such an apparatus is also described.

Abstract: An apparatus for removing particulates from a gas stream is described comprising a filter through which gas may be caused to flow, at least one first electrode for producing an atmospheric glow discharge located near to but spaced apart from the filter, and at least one second counter electrode, the electrodes being connected to an AC voltage supply generating an AC voltage in a frequency within the range of 1 kHz to 200 kHz. A method of removal of particulates from a gas stream comprising causing the gas to flow through such an apparatus is also described.

Abstract: A gas laser includes a laser cavity, mirror means defining an optical path in the cavity, electrodes defining an electric discharge path in the cavity, the electrodes including at least one anode member having a passage therethrough which at one end opens into the cavity, and gas supply means for injecting gas into the cavity through the passage, wherein the wall of the passage at said one end and the exterior of the anode member around the end of said passage is electrically insulated and an electrically conducting anode surface defining the root of the discharge is provided inwardly of the perimeter of the open end of the passage.

Abstract: An electric discharge apparatus, for example a gas laser or discharge lamp, includes first and second electrodes defining a first discharge path and third and fourth electrodes defining a second discharge path alongside the first. A respective impedance is associated with any electrical connection between electrodes. The electrodes are electrically arranged such that either the current flow of a discharge along the first path is so different from the current flow of a discharge along the second path that, overall, the discharges repel one another, or stable electric discharges which coalesce are generated between respective electrodes of the first and second sets.A multi-electrode plasma torch is also provided comprising an electrode holder from which a plurality of electrodes project and a pilot electrode common to more than one of the electrodes.

Abstract: This invention relates to the construction and use of plasma arc furnaces; more particularly it relates to a transferred arc mode of operation in such furnaces. In more detail a plasma arc furnace according to this invention comprises at least two stationary plasma torches positioned at or near the upper end of a furnace chamber and directed downwardly at an inclined angle towards an electrically conducting vessel for containing melt produced in the furnace and at least one electrical return anode connection made to said vessel at a point above the point of coalescence of the arcs produced, in use, by the torches.