High alumina cement is produced in a submerged combustion melter, cooled and ground.

A method of producing cement clinker and a second calcined material, wherein the cement clinker is produced in a first production line and the second calcined material is produced from a raw material in a second production line by carrying out the following procedures e) optionally drying the raw material in a dryer, g) calcining the optionally dried raw material in a rotary kiln to obtain the second calcined material, wherein the sensible heat of a hot gas in the first production line is used as a heat source in the calcining step g) for calcining the raw material, and wherein the rotary kiln exhaust gas coming from the calcining step g) is introduced into the first production line for the secondary combustion of the rotary kiln exhaust gas.

A cooler for cooling bulk material such as cement clinker may include a stationary aeration grate that is for receiving the bulk material is passably by a flow of cooling gas, a conveyor unit having conveyor planks that are disposed above the aeration grate and that for transporting the bulk material are movable in a reciprocating manner in a conveying direction and counter to the conveying direction, a seal assembly that prevents grate riddlings and is attached to the stationary aeration grate, and a drive element that drives the conveyor planks and extends through the stationary aeration grate. The seal assembly may lie against the drive element, and spacing between the seal assembly and the drive element may be adjustable. Further, a method for preventing grate riddlings in a cooler may involve in the event of wear decreasing the spacing between the seal assembly and the drive element.

A cooler for cooling bulk material such as cement clinker may include a stationary aeration grate that is for receiving the bulk material is passably by a flow of cooling gas, a conveyor unit having conveyor planks that are disposed above the aeration grate and that for transporting the bulk material are movable in a reciprocating manner in a conveying direction and counter to the conveying direction, a seal assembly that prevents grate riddlings and is attached to the stationary aeration grate, and a drive element that drives the conveyor planks and extends through the stationary aeration grate. The seal assembly may lie against the drive element, and spacing between the seal assembly and the drive element may be adjustable. Further, a method for preventing grate riddlings in a cooler may involve in the event of wear decreasing the spacing between the seal assembly and the drive element.

The present invention relates to the technical field of building materials, in particular to a method for quantitatively regulating the content of periclase in cement. The method comprises: calculating calcination temperature according to formula I; and the formula I is as follows: z=(y−x+3.767)/0.0012 (I), wherein, x represents the content of MgO in the cement clinker, and the unit is wt %; y represents the target content of periclase in the cement, and the unit is wt %; and z represents the calcination temperature, and the unit is ° C. According to the method for quantitatively regulating the content of periclase in cement provided by the present invention, the expected content of periclase in cement can be more accurately obtained, which is more conducive to utilizing the expansion of cement to guide the practical requirements of cement applications in engineering.

The present invention relates to the technical field of building materials, in particular to a method for quantitatively regulating the content of periclase in cement. The method comprises: calculating calcination temperature according to formula I; and the formula I is as follows: z=(y−x+3.767)/0.0012 (I), wherein, x represents the content of MgO in the cement clinker, and the unit is wt %; y represents the target content of periclase in the cement, and the unit is wt %; and z represents the calcination temperature, and the unit is ° C. According to the method for quantitatively regulating the content of periclase in cement provided by the present invention, the expected content of periclase in cement can be more accurately obtained, which is more conducive to utilizing the expansion of cement to guide the practical requirements of cement applications in engineering.

A rotary cooler is provided, consisting of a plurality of transport tubes for transporting material to be cooled, wherein the plurality of transport tubes are arranged about an axis of rotation and are adapted to be filled jointly via a filling region with material to be cooled, characterized in that each transport tube is arranged substantially concentrically in a cooling tube in which a cooling medium flows and cools the material to be cooled via the wall of the transport tube. Furthermore, a method for operating said rotary cooler is provided.

A rotary cooler is provided, consisting of a plurality of transport tubes for transporting material to be cooled, wherein the plurality of transport tubes are arranged about an axis of rotation and are adapted to be filled jointly via a filling region with material to be cooled, characterized in that each transport tube is arranged substantially concentrically in a cooling tube in which a cooling medium flows and cools the material to be cooled via the wall of the transport tube. Furthermore, a method for operating said rotary cooler is provided.

The present invention refers to a manufacturing process of artificial pozzolan which has the final color gray. In order to perform the processes in the desired way, the kiln atmosphere shall contain low oxygen concentration and the presence of reducing agents. However the presence of carbon monoxide at the kiln outlet is not desirable, due to environmental impacts and the increase in specific heat consumption of the kiln. So the process described in this invention comprises the following steps: heating (1), which consists of heating the raw materials to a temperature between 100-350° C. until drying of the material to a moisture mass fraction of 0-5% (wet basis); mixing (2), which consists of mixing the dry raw materials from the heating process with the right proportion of fuel, in from 1% to 5% in mass fraction, according to the concentration of hematite present in the raw material; calcining (3), which consists of heating the fuel and raw materials blend to a temperature between 700-900° C., with oxygen concentration between 1-5% and, finally, cooling (4), which consists of an initial step of rapid decrease in pozzolan temperature until 600° C. and a final step of slow decrease in pozzolan temperature until 120° C.

The present invention refers to a manufacturing process of artificial pozzolan which has the final color gray. In order to perform the processes in the desired way, the kiln atmosphere shall contain low oxygen concentration and the presence of reducing agents. However the presence of carbon monoxide at the kiln outlet is not desirable, due to environmental impacts and the increase in specific heat consumption of the kiln. So the process described in this invention comprises the following steps: heating (1), which consists of heating the raw materials to a temperature between 100-350° C. until drying of the material to a moisture mass fraction of 0-5% (wet basis); mixing (2), which consists of mixing the dry raw materials from the heating process with the right proportion of fuel, in from 1% to 5% in mass fraction, according to the concentration of hematite present in the raw material; calcining (3), which consists of heating the fuel and raw materials blend to a temperature between 700-900° C., with oxygen concentration between 1-5% and, finally, cooling (4), which consists of an initial step of rapid decrease in pozzolan temperature until 600° C. and a final step of slow decrease in pozzolan temperature until 120° C.