A method for manufacturing clinker including the steps of sintering raw meal in a kiln to clinker, preheating the raw meal in a preheater using a main flue gas stream from the kiln as a heat source, dedusting the main flue gas downstream from the preheater at a temperature below the boiling point of mercury, thereby obtaining mercury-loaded dust and withdrawing a bypass flue gas stream from the kiln. Implementation of the method results in efficient removal of the mercury from the process if mercury in the bypass flue gas is evaporated by injecting at least a fraction of the mercury-loaded dust into the bypass flue gas stream. Subsequently, the bypass flue gas is dedusted and cooled down. The mercury can be adsorbed by injecting an adsorbent like activated charcoal into the bypass flue gas. With the subsequent removal of the adsorbent, mercury is finally removed from the process.

Process for operating a cement or lime plant comprising a cement or lime kiln and a calciner, wherein heat is generated by combustion of a fuel in the kiln and/or calciner, wherein a gas fed to the kiln and the calciner or to the calciner for combustion of the fuel contains an oxygen rich exhaust gas from a bioreactor containing photoautotrophic organisms and wherein the plant is preferably operated in the oxyfuel mode by using exhaust gas from the kiln and/or calciner together with the oxygen from the bioreactor as the gas fed to the kiln and/or calciner for combustion of the fuel.

A method for manufacturing clinker including the steps of sintering raw meal in a kiln to clinker, preheating the raw meal in a preheater using a main flue gas stream from the kiln as a heat source, dedusting the main flue gas downstream from the preheater at a temperature below the boiling point of mercury, thereby obtaining mercury-loaded dust and withdrawing a bypass flue gas stream from the kiln. Implementation of the method results in efficient removal of the mercury from the process if mercury in the bypass flue gas is evaporated by injecting at least a fraction of the mercury-loaded dust into the bypass flue gas stream. Subsequently, the bypass flue gas is dedusted and cooled down. The mercury can be adsorbed by injecting an adsorbent like activated charcoal into the bypass flue gas. With the subsequent removal of the adsorbent, mercury is finally removed from the process.

In a method for reducing the NOx emissions of a rotary kiln of a clinker production plant, fuel supplied through a burner of the rotary kiln is burned along with primary air fed through the burner, wherein the primary air has a lower oxygen content and the primary air has an oxygen content reduced relative to that of the ambient air and a temperature increased relative to that of the ambient air, and the primary air is obtained by mixing ambient air with exhaust gas from the rotary kiln or from a heat exchanger connected to the rotary kiln and used for preheating raw meal. The primary air is further obtained by mixing with hot air, in particular waste air from a clinker cooler.

In a method for reducing the NOx emissions of a rotary kiln of a clinker production plant, fuel supplied through a burner of the rotary kiln is burned along with primary air fed through the burner, wherein the primary air has a lower oxygen content and the primary air has an oxygen content reduced relative to that of the ambient air and a temperature increased relative to that of the ambient air, and the primary air is obtained by mixing ambient air with exhaust gas from the rotary kiln or from a heat exchanger connected to the rotary kiln and used for preheating raw meal. The primary air is further obtained by mixing with hot air, in particular waste air from a clinker cooler.

The invention relates to a method and plant for producing cement clinker, comprising the steps of: burning raw materials to form cement clinker in a furnace, preheating the raw materials with flue gases of the furnace, and dehumidifying and cooling flue gases of the furnace by means of a condensation heat exchanger.

A conveying device for conveying bulk material for a plant for producing cement clinker, wherein the plant for producing cement clinker operates in the recirculation process and/or in the oxy-fuel process, and wherein the conveying device has a connection to the plant, in which the bulk material to be transported passes into the plant. The connection between the conveying device and the plant for producing cement clinker has a gas supply for pressurizing the connection with recirculation gas. Also a method.

Apparatus. methods. and systems for heat treatment of solid materials utilizing an indirect rotary calciner comprising one or more thermal expansion tolerant inner tubes fixed to an outer rotating shell. for example. by one or more resilient support members. The described methods of thermal treatment may be particularly utilized with cement and lime production processes and/or other heat treatment applications. such as pyrolysis.

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.