A process for activating clays having high residual moisture by: feeding wet clay into a device for drying, comminuting the previously dried clay in a device for comminuting, thermally activating the comminuted clay in an entrained flow reactor or in a fluidized bed reactor in which the comminuted clay is in suspension in a hot gas, removing the gas from the entrained flow reactor or the fluidized bed reactor in a device for removing, and cooling the thermally activated clay in a device for cooling with a cooling gas, and to a corresponding plant. The cooling gas, heated after cooling the thermally activated clay, is combined with the gas from the reactor, and the combined gases are introduced into the drying device. The drying air is filtered after drying, and clay removed by filtration is unified with the dried clay.

A cement manufacturing plant includes a raw meal mill, at least one preheater string, a clinker furnace and a clinker cooler including a first section and a second section, wherein a preheater exhaust gas recirculation device is provided for recirculating exhaust gas leaving the at least one preheater string into the first section of the clinker cooler, and wherein the cement plant is configured for switching between an air operation mode and an oxyfuel operation mode, includes a first switching device for connecting either a source of air or a source of oxygen rich gas to a burning zone of the clinker furnace burner, and a second switching device for either establishing or separating a connection of the preheater exhaust gas recirculation means to the first section of the clinker cooler.

The invention relates to a process plant (20) for converting a solid input material into a solid process product. The process plant (20) includes a calciner which is connected to a heat exchanger (26) and to which the input material can be continuously supplied for heating in order to transform the input material into an intermediate product. In the process plant (20) there is a kiln for converting the intermediate product into the process product by means of thermal treatment, raw gas being produced in doing so. The process plant (20) has a raw gas line system (50) comprising a raw gas line (50.1) which extends from the kiln to the calciner and through which the raw gas can flow from the kiln into the calciner for transferring raw gas heat to the input material, and includes a cooling device for cooling the process product after the thermal treatment in the kiln by transferring heat from the process product to a cooling gas containing oxygen, as a result of which a hot gas containing oxygen is generated. According to the invention, in the process plant (20) there is a waste air purification device for oxidizing raw gas, which is connected to the calciner via a raw gas line system (50), wherein a hot gas line system which is used for supplying hot gas generated from the cooling device is attached to the raw gas line system (50). The invention also relates to a method for converting a solid input material into a solid process product and to a method for purifying raw gas produced during the manufacture of cement.

The invention relates to a process plant (20) for converting a solid input material into a solid process product. The process plant (20) includes a calciner which is connected to a heat exchanger (26) and to which the input material can be continuously supplied for heating in order to transform the input material into an intermediate product. In the process plant (20) there is a kiln for converting the intermediate product into the process product by means of thermal treatment, raw gas being produced in doing so. The process plant (20) has a raw gas line system (50) comprising a raw gas line (50.1) which extends from the kiln to the calciner and through which the raw gas can flow from the kiln into the calciner for transferring raw gas heat to the input material, and includes a cooling device for cooling the process product after the thermal treatment in the kiln by transferring heat from the process product to a cooling gas containing oxygen, as a result of which a hot gas containing oxygen is generated. According to the invention, in the process plant (20) there is a waste air purification device for oxidizing raw gas, which is connected to the calciner via a raw gas line system (50), wherein a hot gas line system which is used for supplying hot gas generated from the cooling device is attached to the raw gas line system (50). The invention also relates to a method for converting a solid input material into a solid process product and to a method for purifying raw gas produced during the manufacture of cement.

A method and device for the combined manufacturing of cement clinker and calcined clay, in a cement manufacturing line by the steps: providing, preheating and precalcining a cement raw meal in a preheater and calciner section, sintering the precalcined cement raw meal in a rotary kiln and cooling the resulting cement clinker with a counter current air stream in a clinker cooler, and in a clay manufacturing line by the steps: providing and preheating a clay raw material in a heat exchange section, and calcining the preheated clay raw material suspended in gas in a flash calciner. Hot air from the cooler is divided into a first combustion air stream for sintering the cement raw meal and a second combustion air stream for calcining the clay raw material. Exhaust gas from calcining clay raw material is fed into the calcination of the preheated cement raw meal.

A method and device for cooling and comminuting hot cement clinker in a cooler. The cooler has an inlet region for receiving the hot clinker, a recuperation region, a final cooling region having a clinker cooling device, an opening for blowing cooling air into the recuperation region, a tertiary air line for conducting away heated cooling air, an outlet region for discharging cooled clinker, and at least one conveyor to transport the clinker through the cooler. The hot clinker is tipped into the cooler through an input opening into the inlet region. The clinker is transported by the conveyor from the inlet region, through the recuperation region and the final cooling region to the outlet region, and ambient air is blown as cooling air into the recuperation region through the opening. Comminution of the clinker is provided by a device arranged in the recuperation region.

A cement clinker manufacturing method implemented in a continuous production facility having at least one fuel combustion area for firing an inorganic raw material into hot clinker, then the hot clinker is cooled in: a first cooling step in a first cooler; and a second consecutive cooling step in a second cooler. The first cooling step is continually carried out by blowing an oxygen gas on the hot clinker to obtain partially cooled clinker, and all the heated oxygen gas, created by the first cooler, is sent to the combustion area for use as combustion gas by adjusting the amount of oxygen gas, blown in the first cooler, such as to cover the combustion gas needs of the facility without any excess; and the partially cooled clinker is stored in a storage chamber, and the second cooling step is intermittently carried out on the partially cooled clinker.

A process is disclosed for decarbonation of limestone, dolomite or other carbonated materials and hydration of decarbonated limestone, dolomite or other carbonated materials. The process may include: heating particles of carbonated materials in a reactor of a first circuit; conveying the particles of carbonated materials by a first entraining gas; transferring the decarbonated particles to a second circuit, in which a second gas circulates, the circuit including a hydration section; hydrating the decarbonated particles; and transferring at least a portion of the heat generated by the hydration of the decarbonated particles to the second gas being substantially free of carbon dioxide;. The first and second circuits are separated by first selective separation means allowing the passage of solids while substantially preventing the passage of the gases.

A low-carbon production method and production system for cement clinker. The production method comprises calcining a metal oxide, which is obtained by converting carbonate in a raw material by means of a methane dry reforming reaction, to form cement clinker, and meanwhile obtaining synthesis gas. The production system uses a reformer furnace for methane dry reforming of carbonate to replace a carbonate decomposition furnace in an existing cement production system.

The invention provides a powder-gas heat exchanger for exchanging heat between a powder stream and a gas stream in counter-current flow comprising a powder stream mass flow rate substantially equal to a gas stream mass flow rate in a vertical shaft heat exchanger. A hot gas stream may be adapted for use in heating a cool solids stream, or a cool gas stream may be adapted for use in cooling a hot solids stream.