Abstract: A cement production plant may include a preheater for preheating raw meal, a calciner for calcining the preheated raw meal, and a furnace with a furnace burner for firing the raw meal to form cement clinker. The furnace has a combustion gas inlet for admitting a combustion gas with an oxygen content of 30% to 75% into the furnace. The cement production plant may also include a cooler for cooling the cement clinker. The calciner and the furnace each have at least one respective fuel inlet for admitting at least one fuel into the calciner and the furnace. The calciner and the furnace each have at least one respective inert gas inlet for respectively admitting inert gas into the calciner and the furnace.

Abstract: A process for producing cement clinker may involve preheating raw meal in a preheater, calcining the preheated raw meal in a calciner, burning the preheated and calcined raw meal in a furnace to give cement clinker, cooling the cement clinker in a cooler, branching off a portion of the furnace offgases flowing out of the furnace as bypass gas, cooling the bypass gas in a mixing chamber with a cooling gas, and separating out dust present in the bypass gas. The cooling gas is formed at least partly or completely from the bypass gas and/or the calciner offgas and/or the preheater offgas. The cooling gas is introduced into the mixing chamber in a ratio of 2-10:1 relative to the bypass gas.

Abstract: A process for producing cement clinker, may involve preheating raw meal in a preheater, calcining the preheated raw meal in a calciner, and burning the preheated and calcined raw meal in a furnace to give cement clinker. The furnace may be supplied with a combustion gas having an oxygen content, and the temperature within the furnace is ascertained. The process may involve cooling the cement clinker in a cooler. The oxygen supply to the furnace is under closed-loop control as a function of the temperature ascertained within the furnace. The temperature ascertained is compared with a target value and, in the event of any variance of the temperature ascertained from the target value, the oxygen supply to the furnace and/or to the calciner is increased or decreased. The target value is adjusted depending on a particle size distribution and/or a lime standard.

Abstract: A process for catalytic oxidation of ammonia gas by way of an oxygen-containing gas in a presence of a noble metal-containing catalyst may be employed to give nitrogen monoxide. A temperature of an ammonia/air mixed gas may be optimized in respect of nitrogen monoxide selectivity of the reaction before contact with the catalyst. Examination of catalytic NH3 oxidation according to 4NH3+5O2?4NO+6H2O revealed that an optimum mode of operation of an NH3 burner in an HNO3 plant is not to be achieved by maintenance of a constant gauze temperature of the catalyst gauze by automatic setting of the NH3:air ratio. Rather, there is an optimum temperature for each process condition that should be set not by changing the NH3:air ratio but instead by altering the temperature of the NH3/air mixed gas before contact with the catalyst gauzes.

Abstract: An apparatus for thermally treating mineral solids includes a preheater, a separating apparatus arranged at an outlet of an entrained flow reactor, and a thermal treatment zone at an outlet of a gas stream of the separating apparatus, with an outlet of the treatment zone being connected to an inlet of the preheater for the gas stream.

Abstract: A cooler for cooling bulk material, in particular cement clinker, may include a cooling gas chamber through which a cooling gas flow for cooling the bulk material can flow in crosscurrent, and a conveying device for conveying the bulk material through the cooling gas chamber in a conveying direction. The cooling gas chamber may include a first cooling gas chamber portion with a first cooling gas flow and a second cooling gas chamber portion, adjoining the first cooling gas chamber portion in the conveying direction of the bulk material, with a second cooling gas stream. The cooler may include a separating apparatus for gastight separation of the cooling gas chamber portions from one another. The separating apparatus may have sealing element and at least one suspension element, to which a plurality of sealing elements are attached.

Abstract: A process for producing sulfuric acid and cement clinker may use calcium sulfate that is formed as a solid by-product and separated off in phosphoric acid production in a reaction of raw phosphate with sulfuric acid to form phosphoric acid. The process comprises treating calcium sulfate separated from the phosphoric acid with an acid to obtain a suspension comprising purified calcium sulfate, separating the purified calcium sulfate in solid form from the liquid phase of the suspension, mixing the purified calcium sulfate with admixtures and reducing agents to obtain a raw meal mixture for cement clinker production, burning the raw meal mixture to obtain the cement clinker, with formation of sulfur dioxide as offgas, and subjecting the sulfur dioxide formed to offgas purification and feeding the sulfur dioxide as raw material to sulfuric acid production to produce the sulfuric acid. The sulfuric acid produced may be used as starting material in phosphoric acid production.

Abstract: A process can be used for recovering 1-methoxy-2-propanol and 2-methoxy-1-propanol from an aqueous effluent stream by liquid-liquid-extraction, followed by extractive distillation, distillation of methoxypropanols from the extraction solvent, and distillative separation of the methoxypropanol isomers. Recovered extraction solvent is recycled to the extraction and extractive distillation. Heat transfer from recovered extraction solvent to the extract fed to the extractive distillation reduces energy demand of the process. A facility for this process contains a countercurrent extraction column, an extractive distillation column, a solvent recovery distillation column, an isomer separation distillation column, and a heat exchanger for transferring heat from recovered extraction solvent to the extract fed to the extractive distillation.

Abstract: A process for making propene oxide involves reacting propene with hydrogen peroxide in the presence of methanol, a titanium zeolite epoxidation catalyst, and nitrogen containing compounds present in an amount of from 100 to 3000 mg/kg of hydrogen peroxide. Non-reacted propene is separated from the reaction mixture; the propene depleted reaction mixture Is continuously distilled in a distillation column providing an overhead product stream containing propene oxide and methanol and a bottoms product stream; and propene oxide is separated from the overhead product stream. An acid is added to the propane depleted reaction mixture and/or to the distillation column at the same level or above the feed point for the propene depleted reaction mixture and/or contacted to the feed to the distillation column to provide an apparent pH in the bottoms product stream of from 3 to 4.5, which reduces the nitrogen content of the separated propene oxide.

Abstract: A roller mill for comminuting bulk material may include a first grinding roller and a second grinding roller that are arranged opposite one another and can be driven in opposite directions. A grinding gap exists between the grinding rollers. A floating bearing unit may be configured to receive the first grinding roller, and a fixed bearing unit may be configured to receive the second grinding roller. The floating bearing unit includes two bearings, each of which receives one end of the first grinding roller. Hydraulic actuators are mounted on the floating bearing unit for applying a force to the floating bearing unit. The bearings of the floating bearing unit are connected to one another via a synchronization device that includes a coupling element, which in a coupling position prevents a relative movement of the bearings and in a free position permits a relative movement of the bearings.

Abstract: An absorption tower for production of nitric acid by the Ostwald process may include sieve trays that are arranged on top of one another and each spaced apart from one another, a water inlet in an upper region of the absorption tower, an inlet for gaseous nitrogen oxides in a lower region of the absorption tower, and a column bottom that is disposed in the lower region of the absorption tower beneath a lowermost sieve tray and is divided by a dividing wall into a first, radially inner region and at least a second, radially outer region. Nitric acid that trickles down from the lowermost sieve tray with a higher concentration can be collected in a middle region. The less-concentrated nitric acid that then effluxes from sieve trays higher up can then be collected separately in a region farther outward.

Abstract: An apparatus for thermally treating lithium ores and other mineral raw material may include a comminution apparatus, a pelletization apparatus, and a thermal treatment apparatus. The pelletization apparatus can be a mechanical fluidized bed reactor. Further, a process for thermally treating lithium ore and other mineral raw material may involve comminuting the mineral raw material in a comminution apparatus to form a first product, pelletizing the first product in a mechanical fluidized bed reactor to form a second product, and thermally treating the second product in a thermal treatment apparatus. Ninety percent of all particles in the second product may have a particle size between 50 ?m and 500 ?m.

Abstract: An apparatus for steam reforming includes a reactor, a condensate separator, a condensate stripper, and a steam boiler. The reactor produces hydrogen and is connected to the condensate separator such that a gas mixture is conducted from the reactor into the condensate separator. The condensate separator and the condensate stripper are connected so that condensate separated out in the condensate separator is conducted into the condensate stripper. The condensate separator and the steam boiler are connected such that cleaned condensate can be conducted into the steam boiler. The steam boiler is connected to the reactor and to the condensate stripper in a steam-conducting manner. The boiler water feed line of the steam boiler is connectable to the condensate stripper in a liquid-conducting manner. A supply from the boiler water feed line is at a same location of the condensate stripper as a supply of the condensate from the condensate separator.

Abstract: An arrangement includes a steam saturator for producing saturated steam and a device for refeeding the liquid evaporated in the steam saturator. The steam saturator includes a steam inlet via which steam is delivered to the steam saturator, a steam outlet for the saturated steam produced, a condensate inlet via which condensate is delivered to the steam saturator, and a condensate return line. In a lower region of the steam saturator, a condensate liquid level that is fluidically connected to the condensate return line is maintained. The condensate return line is connected to the device, which is a condenser and comprises a cooling apparatus for condensing steam. In the steam saturator, the evaporated liquid is replaced only if the condensate level in the steam saturator drops, through condensation of saturated steam delivered from the steam saturator to the condenser and is then condensed in the condenser by the cooling apparatus.

Abstract: A roller press device for milling input material may include a fixedly mounted fixed roller having a roller shaft mounted at least approximately in a fixed position, a loosely mounted loose roller having a roller shaft that can be arranged in a variable position, a frame supporting at least the fixed roller and optionally also the loose roller, and a force application unit acting on the loose roller at a force application point. The fixed and loose rollers can be mounted and positioned relative to one another for applying a milling force. The loose roller may be mounted so as to pivot about a pivot axis in a manner of a one-sided lever such that the relative position of the loose roller relative to the fixed roller can be defined by said pivot movement. The one-sided lever may be formed between the pivot axis and the force application point.

Abstract: A process may involve treating calcium sulfate separated from phosphoric acid with acid to obtain a suspension comprising purified calcium sulfate, separating the purified calcium sulfate in solid form from a liquid phase of the suspension, treating the purified calcium sulfate with water or with a salt- and/or chelate ligand-containing aqueous solution to leach rare earths out of the calcium sulfate, separating the further-purified calcium sulfate in solid form from the liquid phase of the suspension, mixing the purified calcium sulfate that is separated off with admixtures and reducing agents to obtain a raw meal mixture for cement clinker production, burning the raw meal mixture to obtain the cement clinker and thereby forming sulfur dioxide as offgas, and feeding the sulfur dioxide as raw material to sulfuric acid production to produce the sulfuric acid.

Abstract: A process for producing nitric acid by the Ostwald process involves reacting ammonia with atmospheric oxygen as primary air to afford a NOx-containing gas stream in an ammonia oxidation reactor at a first pressure and absorbing the NOx-containing gas stream in water in an absorption apparatus at a higher, second pressure. Nitric acid is bleached with bleach air as secondary air at approximately the first pressure. The secondary air is brought to an operating pressure of the bleaching operation via a separate secondary air compressor or compressor stage. The separate secondary air compressor is independent of the compressor that brings the primary air to the first pressure. Compression to the second higher pressure at which the absorption of the NOx gases is performed in the absorption apparatus is provided only downstream of the bleaching operation.

Abstract: 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.

Abstract: A process for ammonia synthesis in a synthesis circuit may involve circulating a gas mixture comprising nitrogen, hydrogen, and ammonia with a conveying device (2) in the synthesis circuit, reacting nitrogen and hydrogen at least partly to ammonia in a converter, and cooling the gas mixture in a cooling device such that ammonia condenses out of the gas mixture. The disadvantages of adsorption drying and of absorption are avoided as hydrogen and nitrogen are introduced at mutually different sections into the synthesis circuit. The process may also involve introducing nitrogen in a flow direction upstream of the converter and/or directly into the converter in the synthesis circuit.

Abstract: A control system for a device for continuously conveying material is provided for at least one conveyor belt device adapted for continuously conveying the material and having at least one conveyor belt. The conveyor belt device can be operated by one or more drives in working processes to provide a predeterminable setpoint conveyor flow. The control system is configured to register at least one value of a power and/or energy consumed by at least one of the drives during a working process and to determine an energy efficiency for the respective working process and for the predetermined setpoint conveyor flow with the aid of the at least one value of the consumed power and/or energy. The control system also configured to provide control data relating to drive speed for the at least one drive as a function of the energy efficiency.