A tower structure of a pre-heating tower of a plant for thermally processing minerals may include a plurality of support beams that extend vertically and parallel to one another and are connected to one another via cross beams. The tower structure may further include a plurality of mounting positions, each mounting position for fitting a platform to the tower structure. A cross-sectional profile of at least two of the support beams changes over a height of the tower structure. Further, at least two adjacent support beams may be configured such that there is a greater amount of space between the beams at a bottom end region of the adjacent support beams than at a region above the bottom end region.

A cement clinker producing system, capable of providing a gas containing a carbon dioxide gas at a high concentration by increasing a carbon dioxide gas concentration for a part of an exhaust gas, includes a cyclone preheater to preheat a cement clinker raw material, a rotary kiln to burn the preheated cement clinker raw material so as to provide cement clinker, a calcination furnace to promote decarbonation of the cement clinker raw material, a clinker cooler to cool the cement clinker, a kiln exhaust-gas discharge passages to discharge an exhaust gas generated in the rotary kiln, a combustion-supporting gas supply device to supply a combustion-supporting gas having a higher oxygen concentration than air, a combustion-supporting gas supply passage to guide the combustion-supporting gas to the calcination furnace, and a calcination furnace exhaust-gas discharge passage to discharge a carbon dioxide gas-containing exhaust gas generated in the calcination furnace.

Processes and plants for producing cement clinker, wherein no recirculation of preheater exhaust gases occurs and the ratio of solid fed in to exhaust gas in the preheater is set to greater than 1.0 kg of solid to gas.

A method for denitrification of flue gases and a system, wherein flue gases generated in a rotary kiln are conveyed to a calcining zone for the deacidification of raw cement meal. Aqueous ammonia solution, ammonia, or ammonia-releasing substances for denitrifying the flue gases injected into the calcining zone according to the method of selective non-catalytic reduction (SNCR), and the flue gas stream, together with an ammonia slip generated during the denitrification, is passed through a heat exchanger and through at least one dedusting device. The flue gas is guided through a exhaust gas line via a catalyst for the decomposition of excess ammonia with residues of nitrogen oxide in accordance with a method of selective catalytic reduction (SCR), wherein the catalyst is arranged in a reactor provided in the exhaust line, and is no larger than is required for a sufficient decomposition of the ammonia.

To produce cement clinker by baking of raw meal in a kiln, use is conventionally made of a raw meal preheater in which the heat of the flue gas emerging from the kiln is transferred to the raw meal. In order to remove impurities which accumulate in circulation between the kiln and the raw meal preheater, a part of the flue gas is extracted from the kiln, bypassing the raw meal preheater. The heat generated during the baking of cement clinker can be used particularly efficiently if the flue gases extracted and diverted past the raw meal preheater are used in a boiler to generate hot steam which can subsequently be expanded in a turbine.

Methods for the heat treatment of a material flow and the cleaning of resulting exhaust gases are disclosed. The material flow may be preheated in a preheating zone, burned in a sintering zone, and cooled in a cooling zone. Exhaust gases of the sintering zone may flow through a preheater and be used for preheating the material flow. The exhaust gases leaving the preheater may be cooled at least partially in a comminuting device in interconnected operation or at least partially in a cooling device in direct operation. Exhaust gases may then be at least partly dedusted in a dust filter. A temperature of the dedusted exhaust gas may then be raised before the exhaust gas is cleaned of pollutants in at least one catalyst. A temperature at which the exhaust gases flow through the catalyst in direct operation may be higher, at least in phases, than a temperature at which the exhaust gases flow through the catalyst in interconnected operation.

The description relates to reducing hydrochloric acid in cement kilns. In one aspect, an aqueous copper-based chloride remediator is introduced into contact with combustion gases from a cement kiln. Injection is made into a defined introduction zone under conditions effective for HCl emissions control wherein the temperature is within the range of from 300 F. to 800 F., preferably from 550 F. to 750 F. The resulting gases are discharged from the defined zone following sufficient reaction time to reduce the HCl concentration in the gases.

Providing a cement production apparatus in which raw material is supplied into a duct with being dispersed uniformly so that heat-exchanging efficiency is improved by even preheating and clogging and the like are prevented, so that stable operation can be carried out. Between cyclones at an upper stage and a cyclone at a lower stage disposed below cyclones at an upper stage, a duct 21 is provided to introduce exhaust gas to the cyclones at the upper stage with distributing after flowing upward from the cyclone at the lower stage; at a lower position than a distribution part 23 of the duct 21, a material-supplying pipe 22 is connected for supplying cement raw material; at a connected part of the material-supplying pipe 22 to the duct 21, a material-guiding chute 24 on which the cement raw material is supplied from the material-supplying pipe 22 and which drops it into the duct 21 is provided with protruding into the duct 21; and the material-guiding chute 24 is formed to have a flat upper surface and to be expandable by sliding so that insertion depth of a tip end 24a from an inner-wall surface 21b of the duct 21 is 0.15 to 0.5 times of an inner diameter of the duct 21.

A method for treating exhaust gas in an exhaust gas treatment device of a system may involve withdrawing exhaust gas from a processing device for mechanically and/or thermally processing an inorganic material of the system. The material to be fed to the processing device may be preheated by heat exchange with the exhaust gas. Further, a temperature of the exhaust gas entering the exhaust gas treatment device may be adjusted by adapting the exchange of heat between the exhaust gas and the inorganic material. In some examples, the exhaust gas treatment device may comprise an oxidation catalytic converter and/or a reduction catalytic converter.

To provide a cement production apparatus in which heat-exchanging efficiency can be improved by even pre-heating by supplying material equally to cyclones above a duct and which can perform an operation with low pressure loss and small energy consumption. A cement production apparatus includes: a duct 21 provided between upper cyclones 13A and a lower cyclone 13B being provided below the upper cyclones 13A, the duct 21 in which the exhaust gas drained from the lower cyclone 13B flows upward, distributing and introducing the exhaust gas to the upper cyclones 13A; a plurality of material-supplying pipes 22 for supplying cement raw material provided on the duct 21 below a distribution part 23 to the plurality of the upper cyclones 13A with a same number of distribution outlets 21a among the upper cyclones 13A; and connection ports 22a of the material-supplying pipes 22 to the duct 21 each provided at each of positions corresponding to swirl flows of the exhaust gas poured into the distribution outlets 21a.