Abstract: Provided is a method for drying and comminution of moist, mineral raw materials, including at least one of chalk, marl or clay. The moist, mineral raw material is dried and comminuted in a drier crusher while simultaneously supplying hot gases from a kiln system to form a dried material. The dried material in suspended form is directed to a first separator in which the dried material is separated into a coarse fraction and into a fine fraction. The fine fraction is directed to a separation cyclone and then to the kiln system. The coarse fraction is directed to a dosage means. The dosage means directs a first portion of the coarse material to the drier crusher and a second portion of the coarse material to a separate grinding unit where any hard material components, including at least one of flint, sand or marble, are subjected to grinding to form a ground material. At least a portion of the ground material from the separate grinding unit is supplied to the drier crusher.

Abstract: Described is an apparatus (5) as well as a method for cooling kiln exhaust gases in a kiln bypass (7), which apparatus comprises a mixing chamber (9) for extracting and cooling a portion of the kiln exhaust gases from a kiln system (1, 3), said mixing chamber (9) comprising a tubular housing being provided at one end with an exhaust gas inlet (11) for kiln exhaust gases and provided at its other end with an outlet (13) for cooled exhaust gases, said mixing chamber (9) further comprising a tangential inlet (15) for cooling gases, where the apparatus also comprises a first fan (17) for supplying cooling gases to the mixing chamber (9) and a second fan (19) for drawing the kiln exhaust gases through the kiln bypass (7).

Abstract: Described is a method as well as a plant for drying and comminution of moist, mineral raw materials, such as chalk, marl and clay, by which method the raw materials are dried and comminuted subject to simultaneous supply of hot gases in a drier crusher (8) from which the material is subsequently directed in suspended form to a separator (11) in which it is separated into a coarse fraction which is returned to the drier crusher (8) for further drying and comminution and into a fine fraction which is directed to the next stage of the process and where any hard material components such as flint, sand and marble are subjected to grinding in a separate grinding unit (16). The method and plant is peculiar in that a part quantity of the coarse fraction from the separator (11) is proportionately fed to the separate grinding unit (16) for the grinding of hard material components.

Abstract: The present invention relates to a kiln plant and a method for manufacturing cement. The kiln plant comprises a kiln for burning clinker, a cooler, a calciner followed by a separation cyclone and a burning compartment which is fed tangentially with tertiary air from the cooler. Completely or partially calcined material is routed from the bottom of the burning compartment to the calciner to which exhaust gases from kiln are also vented. The object of the invention is to provide a kiln plant and a method for manufacturing cement. The kiln plant is of a relatively simplified construction and it may advantageously burn fuel with a low reactivity, such as petcoke, anthracite and other grades of coal with a low gas content in the calcining zone.

Abstract: In a generally known cement kiln plant which incorporates a preheater (1), a calciner (2) having a separation cyclone (3), a rotary kiln (4) and a clinker cooler (5), a decomposition chamber (10) is additionally installed for incineration of waste. Waste is introduced into the chamber at a location (12) and decomposed in the chamber by the heat from calcined raw meal which is conveyed to the chamber from the separation cyclone (3) of the calciner via a splitting gate (13) and a pipeline (14). Gaseous products are conveyed to the calciner (2) and burned there, whereas noncombustible by-products are discharged via an outlet (15) of the chamber (10). By utilizing the heat from preheated or calcined raw meal instead of, for example, hot exhaust gases to incinerate waste, any disturbance of the draught conditions of the cement kiln plant can be avoided, and the overall control of the calcining process is improved.

Abstract: In a kiln plant for burning mineral raw materials, e.g. cement raw materials, by means of nitrogen containing, solid fuel, e.g. coal, and which plant comprises a kiln (1), a material cooler (2) coupled after the kiln and a multistring, multistage preheater (18-27 and 18'-27') mounted before the kiln, the one string, the kiln string (18-27), being in direct connection with the kiln riser pipe (8) and the second string, the calcining string (18'-27'), being connected to a separate calcinator (4) to which combustion air is supplied in the form of spent cooler air through an inlet (7), an NO.sub.x -reducing zone is established in the kiln riser pipe (8) and a part of the kiln string from an inlet (13) for nitrogen containing solid fuel of a fuel duct (10) and an inlet (12) of a branch-off (14) for the supply of spent cooler air. The length of the NO.sub.

Abstract: A cement clinker-producing plant has a suspension preheater (1,2,3), a calciner (4) united with a stationary reactor (6) and coolers (7,8). Air is blown up through the cooler (7) into the reactor (6) where a spouted bed, in which the clinker is burnt, is produced. The air flow is controlled so that only clinker particles which have grown to a certain size can fall through the air flow into the cooler (7).

Abstract: In a method and an apparatus for burning away organic components in raw phosphate, the burning taking place in two stages carried out in two reactors each having its separate air supply. A first suspension transport reactor (3) and a second reactor (5) are coupled in series via a separator (4), to which reactors combustion air (9), (11), preheated raw material (14), (15) and, if desired, fuel (8) are supplied separately. The reaction temperature in both reactors preferably lies in the range 700.degree.-850.degree. C. The majority of the organic components are burnt in the first stage which operates with a suspension having a density of 1-50 kg/m.sup.3. The remaining part of the organic components is burnt in the second stage which operates with a suspension density of 75-1600 kg/m.sup.

Abstract: A method of removing cadmium from raw phosphate material in an apparatus comprising a preheater section (2,13) a reactor section (3,4,5), a cooler section (7) and an exit gas cleaning section having a cadmium condenser (6,20,21), where the reactors (3,5) work in series and are formed as suspension reactors, or alternatively as a suspension reactor and a fluid-bed reactor, and where the treated raw phosphate in the first reactor having a short material retention time is suspended in a gas/fuel mixture and through a flash-process heated to a reaction temperature of 750.degree.-1050.degree. C.

Abstract: Raw phosphate material is calcined to remove pollutants, such as organic compounds and sulphides, by heat treatment in two suspension calciners (3,5) arranged in series. Fuel supplied at burners (8) is burnt in the calciners with air, supplied in parallel through pipes (9) from a cooler (7) for the treated material. The material is preheated in a preheater, for instance a pipe (13) and cyclone (2) by exit gases from the calciner before entering the calciners and, after leaving the calciners, is separated from the gas streams in separators (4,6).