Abstract: A method for monitoring a flame of a burner of a lime kiln, including imaging a video stream showing the burner end of the lime kiln; extracting at least one image from the imaged video stream; determining, using a pretrained algorithm, from the at least one image at least one area of interest, wherein the at least one area of interest includes a part of the at least one image showing an area having at least one characteristic portion of the flame and/or burner end; calculating the area of the at least one characteristic portion based on the pixels of the at least one area of interest; and determining at least one quantity of interest based on the calculated area of the at least one characteristic portion.

Abstract: A method and apparatus for treating green liquor from a sulphate pulp mill enhances the clarification of the green liquor and may easily be integrated into existing pulp mills. A first portion of the green liquor from the sulphate pulp mill is clarified in a clarifier to produce a clarified green liquor and a dregs-containing green liquor. The dregs-containing green liquor is filtered in a green liquor filter to produce filtrate and dregs. The filtrate is combined) with the clarified green liquor to produce a first combined stream; and the dregs are filtered in a dregs filter. A second portion of green liquor from the sulphate pulp mill is combined with the dregs-containing green liquor to produce a second combined stream, and the second combined stream is introduced into the green liquor filter. The dregs from step (b) are washed prior to filtering the dregs, the green liquor filter and washer comprising a single structure.

Abstract: A cross-flow filtration apparatus is able to produce cleaner liquid, especially in the filtration of green liquor, then is typically possible. A housing contains a number of vertical filter elements each having a filter surface with first and second sides which are substantially free of filter cake. A higher gas pressure is provided on the first sides of the filter surfaces than the second sides, and filtered liquid passes through the filter surface from the first side to the second side. A first conduit withdraws filtrate from the second side of at least one of the surfaces, and a second conduit withdraws suspension liquid from adjacent the bottom of the filter elements and typically (though not necessarily) recirculates it. Suspension is introduced--such as in a tray with a perforated bottom mounted above the filter elements, and/or the nozzles--so that the suspension flows in a falling film down the first sides and in contact with them, so that filter cake does not form during operation.

Abstract: A filtering method and apparatus pass the suspension (e.g. green liquor) to be filtered in a falling film down a first side of a filtering surface of a filter element at a different (higher) pressure than a second side, so that due to the pressure difference prevailing across the filtering surface the filtrate flows through the filtering surface and separated solids substantially remain in the suspension, without forming an undesirable solids layer on the filtering surface. A uniform liquid film falling on the filtering surface is generated by recirculating suspension from the bottom of the filter housing to an upper portion of the filter element. Nozzles may direct flow toward the filtering surface in localized areas. The method may be practiced continuously or in batches.

Abstract: A method of burning solid fuel having low melting point alkaline compositions, such as alkali metal salts, particularly lignite and salty brown coal. The fuel is introduced into the reaction chamber of a circulating fluidized bed reactor, and is mixed prior to introduction to the reaction chamber with a reactant material capable of reacting with the low melting point alkaline compositions of the fuel to produce high melting point alkali metal compounds during combustion. The temperature in the reaction chamber is kept below the melting point of the formed alkali metal compounds. The reactant material comprises silica oxide or a metal oxide, or hydroxide, of the group consisting of aluminum, calcium, magnesium, iron, titanium, and mixtures of two or more thereof. Kaolin is particularly effective, especially when the molar ratio of Al/(Na and K) is at least 1.0.