Abstract: In a process for the preparation of C2- to C4-olefins, a feed stream comprising oxygenates and steam is passed through at least one fixed-bed zone comprising zeolite catalyst, where the oxygenates are converted catalytically into olefins with high selectivity for lower olefins, and the reaction mixture leaving the fixed-bed zone is separated into a first product stream comprising C2- to C3-olefins and inert gas components, at least one second product stream comprising C4+-olefins, and a third product stream consisting of aqueous phase. In order to improve the yield of lower olefins, the aim is to regulate the temperature of the catalytic reaction in accordance with a target temperature value in the range from 440 to 520° C. specified for the reaction mixture exiting the fixed-bed zone by means of a supplementary stream consisting of olefins and inert gas components fed into the feed stream.

Abstract: In a process for producing synthesis gas by catalytic conversion of hydrocarbons contained in a desulfurized feed gas stream with steam, the mixture of feed gas and steam is preheated by heat exchange at a pressure of 10 to 45 bar to a temperature of 300 to 700° C. and is subsequently heated by heat exchange above a catalyst at a pressure of 10 to 45 bar to a temperature of 650 to 950° C. To minimize the apparatus involved, it is provided that the mixture of feed gas and steam traverses a catalyst bed contained in a reaction tank, and the catalyst bed is heated by thermal radiation and convection.

Abstract: The invention concerns a method for producing melamine by dissolving urea, in which solid, liquid or gaseous media other than the gas mixture consisting of the components formed during the reaction is used to desublime the melamine from the gas phase.

Abstract: The invention relates to a method for producing melamine by decomposing urea inside a fluidised bed reactor, during which the hot reaction gas is cooled inside a gas cooler, and the obtained heat is directly used for pre-heating the fluidizing gas required for creating the fluidized bed.

Abstract: Method and device for manufacturing at least one low olefin from an oxygenate-containing first reaction mixture (11) through conversion by a catalyst (20) to an olefin and paraffin-containing second reaction mixture (21) where the second reaction mixture (21) is flowed through a separation system (300), in which one at least one low olefin-containing first product stream (31) and at least one paraffin-enriched fraction (321) is extracted and where the remaining product stream (322) is at least partially recirculated to the catalyst (20).

Abstract: In a process for the preparation of C2- to C4-olefins, a feed stream comprising oxygenates and steam is passed through at least one fixed-bed zone comprising zeolite catalyst, where the oxygenates are converted catalytically into olefins with high selectivity for lower olefins, and the reaction mixture leaving the fixed-bed zone is separated into a first product stream comprising C2- to C3-olefins and inert gas components, at least one second product stream comprising C4+-olefins, and a third product stream consisting of aqueous phase. In order to improve the yield of lower olefins, the aim is to regulate the temperature of the catalytic reaction in accordance with a target temperature value in the range from 440 to 520° C. specified for the reaction mixture exiting the fixed-bed zone by means of a supplementary stream consisting of olefins and inert gas components fed into the feed stream.

Abstract: Disclosed is a method for the production of urea from natural gas, wherein a) natural gas undergoes partial oxidation or autothermal reformation with a gas containing oxygen in a first step and the raw synthesis gas thus arising, consisting essentially of carbon monoxide, carbon dioxide, methane and hydrogen, can be transformed by catalytic conversion of CO and H2O to form CO2 and H2, whereupon carbon monoxide and methane are removed in a multistep gas cleaning process and the hydrogen is converted into ammonia upon addition of nitrogen, and subsequently, b) the ammonia is recombined with the previously separated carbon dioxide in a second step and the ammonia is thus fully converted into urea.

Abstract: In a process for producing synthesis gas by catalytic conversion of hydrocarbons contained in a desulfurized feed gas stream with steam, the mixture of feed gas and steam is preheated by heat exchange at a pressure of 10 to 45 bar to a temperature of 300 to 700° C. and is subsequently heated by heat exchange above a catalyst at a pressure of 10 to 45 bar to a temperature of 650 to 950° C. To minimize the apparatus involved, it is provided that the mixture of feed gas and steam traverses a catalyst bed contained in a reaction tank, and the catalyst bed is heated by thermal radiation and convection.

Abstract: A method is disclosed for producing a synthetic fuel, especially diesel fuel and in addition gasoline, liquefied petroleum gas and heating gas from a gas mixture comprising an oxygenate wherein the oxygenate is methanol and/or dimethyl ether and/or another oxygenate, through a series of steps, including olefin-formation, oligomerization of the olefins, and several separation steps and recycling steps, in particular the recycling of a stream of saturated hydrocarbons following the oligomerization of olefins back to the olefin-forming stage, to obtain the diesel fuel and the other synthetic fuels in high yield.

Abstract: Method and device for manufacturing at least one low olefin from an oxygenate-containing first reaction mixture (11) through conversion by a catalyst (20) to an olefin and paraffin-containing second reaction mixture (21) where the second reaction mixture (21) is flowed through a separation system (300), in which one at least one low olefin-containing first product stream (31) and at least one paraffin-enriched fraction (321) is extracted and where the remaining product stream (322) is at least partially recirculated to the catalyst (20).

Abstract: The invention relates to a method for the coproduction of methanol and ammonia from natural gas involving the following steps: 1. Natural gas (flow 1) , steam and oxygen are mixed with one another in a reactor A during which the natural gas is partially oxidized and additionally reformed with the aid of catalysts; 2. The gas mixture removed from reactor A is split into a flow (flow 2) for synthesizing methanol in a unit E and into another flow (flow 3) for producing hydrogen; 3. The carbon monoxide present in flow (flow 3) for producing hydrogen is converted into carbon dioxide inside reactor B with the aid of catalysts and intermediate cooling stages; 4. Remaining impurities such as methane, traces of carbon monoxide and argon are washed out in a cleaning unit D, and hydrogen (flows 6, 8) is fed to the methanol synthesis in unit E and to the ammonia synthesis in unit F; 5.

Abstract: In an apparatus for continuously recovering sulfur from a gas stream containing 0.1 to 3.0 vol-% H2S, further gaseous sulfur compounds and sulfur, the gas stream first is passed over a reduction stage consisting of hydrogenation catalyst and then over a selective oxidation stage consisting of oxidation catalyst. To reduce the amount of apparatus involved, it is provided to arrange the reduction stage and the selective oxidation stage in a reaction tank and to leave a space for introducing a gaseous cooling medium into the gas stream between the two stages.

Abstract: The invention relates to a system unit for desorbing carbon dioxide and other impurities from highly pressurized methanol. Said system unit comprises at least one or more expansion vessels arranged in succession, at least one heat exchanger, and at least one liquid/gas separator. The inventive system unit contains: a) a line (1) through which the intensely cooled methanol leaving expansion vessel (C) is introduced into the heat exchanger (E) from underneath, and; b) a line (2), though which the heated methanol is drawn out of the heat exchanger (E) from the top, and which serves to connect said heat exchanger to a liquid/gas separator inside of which the remaining carbon dioxide still contained in the methanol is desorbed and separated out to the greatest possible extent. This system unit enables the cold due to evaporation, said cold resulting during the desorption of carbon dioxide, to be obtained inside a heat exchanger and constitutes an important cold energy source for carrying out absorption.

Abstract: In a method for the production of propylene, a charge stream containing C4 to C6 olefins is evaporated, superheated, mixed with hot water vapor, the olefins vapor mixture converted on a zeolite catalyst, the reaction mixture formed thereby cooled, and then partially condensed. In order to increase the yield of propylene, the gaseous phase containing ethylene, propylene, C4 to C8 olefins, and additional hydrocarbons that is accumulated during the partial condensation is compressed, the gaseous and liquid phase containing propylene, ethylene, and other light hydrocarbons that exit from the compression step is separated into a gaseous phase containing propylene, ethylene, and other light hydrocarbons and a liquid phase containing C4+ olefins, and the liquid phase is separated into a fraction containing C4 to C6 olefins and a fraction containing C7+ olefins.

Abstract: The invention relates to a heat-recovery boiler (3) consisting of a tube bundle heat exchanger (7) which is incorporated into a pressure vessel (2) downstream of a gasification device. Displacement bodies (9) are inserted into pipes which are flowed around by hot process gas. According to said invention, in order to avoid corrosion problems like metal dusting, said displacement bodies (9) are made of graphite.

Abstract: In a process for the continuous recovery of free tartaric acid from raw materials containing potassium hydrogentartrate, the same are mixed with water and the potassium hydrogentartrate is dissolved. The process is improved in that the suspension is decanted, the clarified liquid is refiltered, the filtrate is cooled to crystallization temperature under a vacuum, the potassium hydrogentartrate crystals formed are dissolved, the solution is subjected to a cation exchange, and the tartaric acid solution obtained is evaporated.

Abstract: An plant unit for fractionating and purifying synthesis gas is described, which is comprised of a device for partially condensing synthesis gas and a device for nitrogen washing, whereat the device for nitrogen washing is adjacent to the device for partial condensation.

Abstract: From a gas stream, which in a process for the selective removal of sulfur-containing components is obtained periodically and in fluctuating amounts and/or with fluctuating concentrations of sulfur-containing components, the sulfur-containing components are absorbed by means of a washing agent, the washing agent loaded with the sulfur-containing components subsequently is regenerated, the sulfur-containing components separated during the regeneration are converted to sulfur, and the regenerated washing agent is recirculated to the absorption. To achieve an inflow of the washing agent loaded with sulfur-containing components to the regeneration, which is uniform in terms of time, amount and/or concentration of the sulfur-containing components, it is provided to temporarily store the loaded washing agent upon absorption.

Abstract: This invention relates to a process for cleaning gas, in particular hydrocarbonaceous gas such as e.g. natural gas, which is contaminated with sulfur in the form of H2S and mercaptans as well as CO2. To remove the undesired sulfur-containing substances in the form of H2S and mercaptan from crude gas, it is proposed in accordance with the invention that the crude gas is introduced into an absorption and regeneration column and washed therein, three gas streams being withdrawn from this absorption and regeneration column, a first exhaust gas stream being introduced into a Claus plant, a second sour gas stream with a low H2S concentration being introduced into another absorption plant, and a third gas stream, the valuable gas with the mercaptans, being cooled and supplied to an adsorption plant, that from this adsorption plant a cleaned valuable gas is withdrawn, and a mercaptan-containing gas stream is subjected to washing, that this concentrated mercaptan-containing gas is supplied to the Claus plant.

Abstract: What is described is a method and an installation for the simultaneous production of methanol synthesis gas, ammonia synthesis gas, carbon monoxide and carbon dioxide from natural gas, in which several plant elements (or plant units) are serially arranged one by one in one single production chain, whereat these elements comprise: a first reactor A, in which the natural gas is transformed under oxygen supply into a synthesis gas mixture comprised of carbon monoxide, carbon dioxide, hydrogen and steam (water vapor), a second reactor B, which allows to control the transformation of carbon monoxide into carbon dioxide, optionally a compressor C for compressing the generated gases, an absorber D for the absorption of carbon dioxide and for obtaining the carbon monoxide-hydrogen mixture used for methanol synthesis, a low-temperature separator E, in which ammonia synthesis gas is obtained by introducing liquid nitrogen, and in which simultaneously carbon monoxide, argon and methane are removed.