Abstract: Disclosed is a plasma reactor for use to treat ores or other material at a very high temperature in order to physically or chemically transform the same. The reactor comprises a vertical, electrically insulated sleeve disposed at the upper end with a hollow torch of a conventional structure, for use to generate a plasma column. A gas is tangentially injected into the torch to create a vortex inside the same. The material to be treated is dropped, in powder form, vertically downward inside the sleeve from the upper end thereof, beside the hollow torch, so as to form a substantially uniform cylindrical curtain of particles falling down into the sleeve. The particles that are centrifugally projected against the internal wall of the sleeve by the vortex escaping from the hollow torch, entirely cover the internal wall of the sleeve and shield, while simultaneously being treated by heat generated by the plasma arc column.

Abstract: Method and device for controlling the erosion of the electrodes of a plasma torch, in which an electrical arc is produced when the electrodes are connected to an electrical supply. An axial magnetic field generated by a system of field coil causes the rotation of the extremities of the arc according to a circular trajectory inside the electrodes. The relative position of the field coils is such that there exists a position on the electrode surface where the value of the total magnetic field is a minimum where the arc runs thereby controlling the erosion of the electrodes. According to the invention, the value of current is periodically varied in the system of field coil used to cause the rotation of the arc, thereby producing a controlled axial displacement of the circular trajectory of the extremity of the arc.

Abstract: The disclosure describes a method and a system for treating gaseous effluents to remove impurities therefrom, these gaseous effluents flowing out from a high temperature reactor, into which a particulate material is being fed. The method comprises directing the flow of gaseous effluents counter-currently through the particulate material which is fed into the reactor, and independently controlling the particulate material feed rate and the velocity of the gaseous effluents so that particles in the gas feed are substantially all trapped by the particulate feed material and are returned to the high temperature reactor. Volatile materials may also be condensed on the particulate feed material. The purified gaseous effluents are then allowed to exit. A system for carrying out this method is also disclosed.

Abstract: The current transducer is of the type comprising a Rogowski coil extending around a first conducting element in which a current to be detected flows. The first conducting element is provided at one end with a first terminal connector. A second conducting element is mounted on the first one so as to cover and preferably embed the external periphery of the coil. The second conducting element is electrically connected to the first conducting element at the end thereof which is opposite to the one end provided with the first terminal connector. A second terminal connector is provided on the second conducting element on the same side of the plane of the coil as the first terminal connector. This arrangement forces the current flowing between the first and second terminal connectors via the first and second conducting elements to flow around the periphery of the coil and thus to shield the coil.

Abstract: A device and a method for detecting and locating faults and/or partial discharges in a gas-insulated electrical equipment, such as gas-insulated bus or cable, a gas-insulated substation or a gas-insulated switchgear. The detecting device comprises a plurality of field coupled current sensors located at given intervals inside the housing of the equipment for detecting any variation of the current flowing through the conducting element extending inside this housing. Each sensor consists of a toroidal helix pick up coil, preferably a differentiating Rogowski coil, located in an annular cavity machined in the wall of the equipment housing and extending all around the conducting element. Each cavity is connected along its entire length to the inner surface of the housing wall by a slit having opposed side walls sufficiently spaced apart to be insulated from each other. Each sensor gives a signal which is proportional to the detected variation of the current.

Abstract: In accordance with the method, the arc supplying current is modulated if necessary for generating an acoustical signal. The acoustical signal generated by the arc is detected and its amplitude which, in practice, is a direct function of the actual length of the arc, is compared to a reference amplitude corresponding to the desired length of the electrical arc, in order to determine the algebraic value of their difference. This algebraic value is used for monitoring at least one element of the machine between which the arc forms, and moving this element proportionally to the so-determined algebraic value in order to increase or reduce the actual length of the arc and to bring this length back to the desired length.