Abstract: There is provided a multi-module counterflow drying apparatus (100) for drying material, the apparatus (100) comprising: a material inlet (102); a material outlet (104); a heat inlet (108) for inputting heat to the apparatus such that the heat traverses the apparatus in the opposite direction than the material; and a plurality of mutually interchangeable modules (110) stacked on top of each other, wherein the material is configured to move in the apparatus from one module to another such that the movement direction of the material in a given module is opposite to the movement direction of the material in a module above or below, wherein each module (110) comprises: movable paddles (210) configured to discontinuously move the material forward in the module (110).

Abstract: There is provided a multi-module counterflow drying apparatus (100) for drying material, the apparatus (100) comprising: a material inlet (102); a material outlet (104); a heat inlet (108) for inputting heat to the apparatus such that the heat traverses the apparatus in the opposite direction than the material; and a plurality of mutually interchangeable modules (110) stacked on top of each other, wherein the material is configured to move in the apparatus from one module to another such that the movement direction of the material in a given module is opposite to the movement direction of the material in a module above or below, wherein each module (110) comprises: movable paddles (210) configured to discontinuously move the material forward in the module (110).

Abstract: An apparatus (100) comprises at least one optical cable (104), a detector (106) and a processing unit (108). An end of an optical cable (104) is placed inside the electric arc furnace (10) for collecting light from the furnace (10). The optical cable (104) conveys the light to the detector (106). The detector (106) separates the light into a plurality of optical bands of the spectrum and transforms strengths of the plurality of optical bands into electrical data. The processing unit (108) measures, for determining a state of the furnace (10), a background of the optical bands in a predetermined manner, at least one characteristic strength level of the optical bands and an average deviation of the strengths of the optical bands from the background on the basis of the electrical data.