A system and method for fluidized reduction of iron ore powder. Use of oxidation increases the iron ore reduction rate. Use of high-gas-velocity processing accelerates iron ore reduction speed and greatly improves the gas-treatment capabilities of a unit-cross-sectional fluidized bed. Use of parallel-connections involving reduced coal gas lessens the volume of gas passing through a single-stage fluidized bed. The invention achieves the highly-effective reduction of iron ore powder in a fluidized bed under near-atmospheric pressure.

The invention relates to multi-stage cement calcining plant suspension preheater of the kind mentioned in the introduction, wherein the preheater comprises a top separator comprising a central tube entering the top separator in a lowermost part of the separator housing whereas the central tubes of the bottom separators enters the separator housing in an upper part of the separator housing.

A system and method for the fluidized direct reduction of iron ore concentrate powder. A two-phase fluidized bed is used for the direct reduction of iron ore concentrate powder. Each phase of the fluidized bed is formed by a bubbling bed and a circulating bed. Use of serial-connection processing involving gas and of high-gas-velocity processing of the circulating bed increase the gas utilization rate and the reduction efficiency of single-phase reduction. Once reduced gases are subjected to preheating, each gas is sent into an initial reduction phase and a final reduction phase so as to implement reduction of minerals. Use of mixed-connection processing involving gas appropriately reduces processing pressure. Hot flue gas produced by combustion in a gas heater is sent to a mineral pre-heating system that is used for pre-heating iron ore concentrate powder.

A method and a sensor device for evaluating residual Sulphur in a cement preheater of a cement kiln, wherein the residual Sulphur is based on the values of the fuel Sulphur content, the fuel rate of consumption, the hotmeal quality and the clinker Sulphur content. A method for evaluating blockage in a cement preheater includes evaluating the residual Sulphur in the cement preheater, determining an agglomeration rate of Sulphur compounds agglomerating on an inner surface of the cement preheater based on the residual Sulphur, and evaluating a level of blockage in at least one predetermined pathway of the cement preheater using a blockage evaluation unit, wherein the level of blockage is based on the agglomeration rate.

A powder sintering system is disclosed. The powder sintering system includes a furnace body, at least one first dispersing device, at least one second dispersing device, a heating device, and a gas introducing device. The furnace body includes a bottom and a side wall defines a funnel shaped chamber. The at least one first dispersing device is located on the bottom of the furnace body, and disperses powder from the bottom of the furnace body to the side wall of the furnace body. The at least one second dispersing device is located on the side wall of the furnace body, and centrifugally disperse powder from the side wall of the furnace body to a center of the funnel shaped chamber. The heating device is located outside the furnace body. The gas introducing device supplies a protecting gas into the funnel shaped chamber.

Described are cementitious reagent materials produced from globally abundant inorganic feedstocks. Also described are methods for the manufacture of such cementitious reagent materials and forming the reagent materials as microspheroidal glassy particles. Also described are apparatuses, systems and methods for the thermochemical production of glassy cementitious reagents with spheroidal morphology. The apparatuses, systems and methods makes use of an in-flight melting/quenching technology such that solid particles are flown in suspension, melted in suspension, and then quenched in suspension. The cementitious reagents can be used in concrete to substantially reduce the CO.sub.2 emission associated with cement production.

Described are cementitious reagent materials produced from globally abundant inorganic feedstocks. Also described are methods for the manufacture of such cementitious reagent materials and forming the reagent materials as microspheroidal glassy particles. Also described are apparatuses, systems and methods for the thermochemical production of glassy cementitious reagents with spheroidal morphology. The apparatuses, systems and methods makes use of an in-flight melting/quenching technology such that solid particles are flown in suspension, melted in suspension, and then quenched in suspension. The cementitious reagents can be used in concrete to substantially reduce the CO.sub.2 emission associated with cement production.

The device for pre-heating cement raw meal for the cement clinker production comprises at least one heat exchanger line for charging cement raw meal in countercurrent flow to the hot gases drawn through the heat exchanger line and a supporting structure (19) for the at least one heat exchanger line, wherein the heat exchanger line comprises a plurality of heat exchangers (8, 9, 10) which are interconnected and through which flow can pass consecutively. The supporting structure (19) comprises stands (20) which jointly form a triangular outline (21) and serve to transfer load into at least one foundation.

A plant for heat treatment of mineral material comprises a reactor having at least one gas inlet for admitting offgases, wherein the reactor comprises an activating region for activating the mineral material and an offgas outlet for ejecting offgases from the reactor, wherein the offgas outlet is connected to the at least one gas inlet in such a way that at least a portion of the offgas is supplied to the reactor. A process for heat treatment of mineral material with a reactor, comprises activating the material in an activating region of the reactor and optionally cooling the material in a cooling region of the reactor, wherein the offgas of the reactor is discharged therefrom, wherein at least a portion of the offgas discharged from the reactor is returned to the reactor.

Described are cementitious reagent materials produced from globally abundant inorganic feedstocks. Also described are methods for the manufacture of such cementitious reagent materials and forming the reagent materials as microspheroidal glassy particles. Also described are apparatuses, systems and methods for the thermochemical production of glassy cementitious reagents with spheroidal morphology. The apparatuses, systems and methods makes use of an in-flight melting/quenching technology such that solid particles are flown in suspension, melted in suspension, and then quenched in suspension. The cementitious reagents can be used in concrete to substantially reduce the CO.sub.2 emission associated with cement production.