A system for conditioning stucco particulate material includes a vessel having separation chamber in communication with a holding chamber having a holding volume therein. The conditioning system includes the holding volume sufficient to condition the stucco particulate material therein and/or a control system configured to delay discharge of the stucco particulate material from the holding chamber. The system for conditioning stucco particulate material is configured to increase residence time of the stucco particulate material in the holding chamber to promote calcining conditioning therein.

Invention relates to a vertical ring shaft kiln comprising a vertical burning region (1); an intermediate sintering zone (Z.sub.3) surrounded by a first wall (10) and an opposite second wall (20) at the burning region (1) to obtain a clinker from a particulate raw material flowing downwards direction.

A method of thermally processing work pieces including providing an insulated chamber having a first end, an opposing second end, and a middle portion disposed between the first and second ends, wherein the first end is inclined with respect to middle portion, creating a thermal gradient within an interior of the insulated chamber, and providing a means for gradually moving a workpiece from the first end to the second end within the created thermal gradient.

A furnace may include at least two vertical shafts, each of which may have at an upper end thereof an inlet for material to be burnt and at a lower end thereof a burnt material outlet. The inlet and the outlet may be connected by a transfer channel. In each case, at least one main burner may be positioned above the transfer channel, and a cooling gas inlet may be positioned below the transfer channel. At least one additional burner may be positioned below the transfer channel in each of the shafts. Such a furnace can be operated such that the material to be burnt in the currently fired shaft is at least partially calcined in a main burning zone above the transfer channel, and then thermally aftertreated in an additional burning zone positioned between the transfer channel and the additional burner.

A furnace may include at least two vertical shafts, each of which may have at an upper end thereof an inlet for material to be burnt and at a lower end thereof a burnt material outlet. The inlet and the outlet may be connected by a transfer channel. In each case, at least one main burner may be positioned above the transfer channel, and a cooling gas inlet may be positioned below the transfer channel. At least one additional burner may be positioned below the transfer channel in each of the shafts. Such a furnace can be operated such that the material to be burnt in the currently fired shaft is at least partially calcined in a main burning zone above the transfer channel, and then thermally aftertreated in an additional burning zone positioned between the transfer channel and the additional burner.

A sintering furnace can have a housing, one or more heating elements, and a conveying assembly. Each heating element can be disposed within the housing and can subject a heating zone to a thermal shock temperature profile. A substrate with one or more precursors thereon can be moved by the conveying assembly through an inlet of the housing to the heating zone, where it is subjected to a first temperature of at least 500? C. for a first time period. The conveying assembly can then move the substrate with one or more sintered materials thereon from the heating zone and through an outlet of the housing.

A sintering furnace can have a housing, one or more heating elements, and a conveying assembly. Each heating element can be disposed within the housing and can subject a heating zone to a thermal shock temperature profile. A substrate with one or more precursors thereon can be moved by the conveying assembly through an inlet of the housing to the heating zone, where it is subjected to a first temperature of at least 500? C. for a first time period. The conveying assembly can then move the substrate with one or more sintered materials thereon from the heating zone and through an outlet of the housing.

Controlling circumferential variability in a blast furnace may include generating a predictive model that sets up a relationship between a standard deviation of a selected state variable, state variables and one or more control variables in blast furnace operation for predicting the standard deviation. A number of circumferential sections of the blast furnace is defined, and the predictive model associated with the selected state variable for each of the circumferential sections is trained based on process data of the blast furnace. A plurality trained predictive models is generated associated with different circumferential sections and different selected state variables. One or more future control variable set points that minimize a sum of the plurality of predictive models, is determined. One or more future control variable set points is transmitted to a control system to control the blast furnace operation.

Controlling circumferential variability in a blast furnace may include generating a predictive model that sets up a relationship between a standard deviation of a selected state variable, state variables and one or more control variables in blast furnace operation for predicting the standard deviation. A number of circumferential sections of the blast furnace is defined, and the predictive model associated with the selected state variable for each of the circumferential sections is trained based on process data of the blast furnace. A plurality trained predictive models is generated associated with different circumferential sections and different selected state variables. One or more future control variable set points that minimize a sum of the plurality of predictive models, is determined. One or more future control variable set points is transmitted to a control system to control the blast furnace operation.

A method of operating a plant having a furnace including at least two vertical shafts connected by an overflow duct, wherein at least one burner is arranged above the overflow duct in each case such that the burner gases therefrom flow downward in burning operation of the respective shaft. A cooling gas supply is provided beneath the overflow duct in each case such that, in combination with the operation of a burner in the burner-operated shaft, the burner gas flowing downward is deflected in the direction of the overflow duct by the cooling gas ascending in the burner-operated shaft, and a supply of cooling gas is adjusted such that the temperature of the burner charge through which the burner gas flows at least in the burner-operated shaft is kept above the deacidification temperature thereof.