Abstract: A method of sorting mined material to separate the mined material into at least two categories is disclosed. The method comprises exposing particles of the mined material to microwave energy and heating the particles depending on the susceptibility of the material in the particles. The method also comprises thermally analyzing the particles using the temperatures of the particles as a basis for the analysis to indicate composition differences between particles and then sorting the particles on the basis of the results of the thermal analysis. The method also comprises compensating for temperature variations in the mined material that is supplied to the method.

Abstract: A method of sorting mined material to separate the mined material is disclosed. The method comprises exposing particles of the mined material to microwave energy and heating the particles depending on the susceptibility of the material in the particles. The method also comprises thermally analyzing the particles using the temperatures of the particles as a basis for the analysis to indicate composition differences between particles and sorting the particles on the basis of the results of the thermal analysis. The method also comprises controlling the temperature of particles as the particles are moved between a station at which particles are exposed to microwave energy and a station at which particles are thermally analyzed.

Abstract: A method of sorting mined material to separate the mined material is disclosed. The method comprises exposing particles of the mined material to microwave energy and heating the particles depending on the susceptibility of the material in the particles. The method also comprises thermally analyzing the particles using the temperatures of the particles as a basis for the analysis to indicate composition differences between particles. The thermal analysis step includes thermally assessing particles against a background surface. The thermal analysis step also includes heating the background surface to a temperature that is different to the temperature of the particles to provide a thermal contrast between the particles and the background surface. The method also comprises sorting the particles on the basis of the results of the thermal analysis.

Abstract: A method of sorting mined material to separate the mined material into at least two categories is disclosed. The method comprises exposing particles of the mined material to microwave energy and heating particles depending on the susceptibility of the material in the particles. The method also comprises allowing sufficient time for heat generated in the particles to be transferred through the particles so that the surface temperature of the particles is a measure of the mass average temperature through the particles. The method further comprises thermally analysing the particles to detect temperature differences between particles which indicate composition differences between the particles; and thereafter sorting the particles on the basis of the results of the thermal analysis.

Abstract: A method of sorting mined material to separate the mined material into at least two categories is disclosed. The method comprises exposing particles of the mined material to microwave energy and heating the particles depending on the susceptibility of the material in the particles. The method also comprises thermally analysing the particles using the temperatures of the particles as a basis for the analysis to indicate composition differences between particles and then sorting the particles on the basis of the results of the thermal analysis. The method also comprises compensating for temperature variations in the mined material that is supplied to the method.

Abstract: A method of sorting mined material to separate the mined material is disclosed. The method comprises exposing particles of the mined material to microwave energy and heating the particles depending on the susceptibility of the material in the particles. The method also comprises thermally analysing the particles using the temperatures of the particles as a basis for the analysis to indicate composition differences between particles and sorting the particles on the basis of the results of the thermal analysis. The method also comprises controlling the temperature of particles as the particles are moved between a station at which particles are exposed to microwave energy and a station at which particles are thermally analysed.

Abstract: A method of sorting mined material to separate the mined material is disclosed. The method comprises exposing particles of the mined material to microwave energy and heating the particles depending on the susceptibility of the material in the particles. The method also comprises thermally analysing the particles using the temperatures of the particles as a basis for the analysis to indicate composition differences between particles. The thermal analysis step includes thermally assessing particles against a background surface. The thermal analysis step also includes heating the background surface to a temperature that is different to the temperature of the particles to provide a thermal contrast between the particles and the background surface. The method also comprises sorting the particles on the basis of the results of the thermal analysis.

Abstract: A method of sorting mined material to separate the mined material into at least two categories is disclosed. The method comprises exposing particles of the mined material to microwave energy and heating particles depending on the susceptibility of the material in the particles. The method also comprises allowing sufficient time for heat generated in the particles to be transferred through the particles so that the surface temperature of the particles is a measure of the mass average temperature through the particles. The method further comprises thermally analysing the particles to detect temperature differences between particles which indicate composition differences between the particles; and thereafter sorting the particles on the basis of the results of the thermal analysis.

Abstract: An apparatus (50) for contacting a gas stream (62) with solid particulate material includes two contacting zones (58, 60). Sets of angled blades (54, 56) cause gas flowing through the contacting zones (58, 60) to have a swirling circumferential velocity. Solid particulate material is fed from hopper (70) via line (72) to the upper contacting zone (56), in which the swirling gas flow causes a turbulent band of particles (60) to form. Contact between the gas and the solid occurs in this band of particles. Overflow of particles from band (74) flows down conduits (76, 77) and into lower contacting zone (58). The swirling gas flow in contacting zone (58) causes a turbulent band of particles (78) to be established. The gas stream enters at conduit (62) and travels through the turbulent band of particles (78) in the lower contacting zone (58). The gas then passes through restriction (66), through the turbulent band of particles (74) in upper contacting zone (60) and then leaves the apparatus (50) via outlet (68).

Abstract: A process for the treatment of waste materials such as spent cathode liners involving combustion of the contained carbonaceous material, decomposition of the contained cyanides, sulphides and nitrides, and recovery of fluoride values by a sulpholysis reaction, is characterized in that the sulpholysis reaction is carried out in a separate stage. The process enables a recovgery of fluoride values from smelter wastes which is especially favourable environmentally. A further advantage of the invention is that recovery of the contained fluoride values, initially in the form of gaseous fluoride species, may subsequently be treated with alumina to produce aluminium trifluoride, which is of significant economic importance.