Abstract:
The present invention relates to the production of metal oxide from metal salts, in particular from aluminum hydroxide, wherein the metal salt is preheated in a first preheating stage, precalcined in a second preheating stage and calcined to metal oxide in a fluidized-bed reactor, and wherein the product obtained then is cooled in at least one suspension heat exchanger and subsequently in a multi- stage indirect cooler. To reduce the energy demand of a calcining plant, fluidizing air is supplied to the reactor with a temperature of up to 150 °C, and before entering the first preheating stage the metal salt is at least partly supplied to a hydrate drier in which it is indirectly heated with heat transfer medium from the first stage of the indirect cooler and dried.
Abstract:
In accordance with the invention, refining raw materials containing organic constituents, such as raw materials containing oil and/or bitumen, in particular oil or tar sand or oil shale, is effected with the following steps: supplying the raw materials to an expulsion stage and expelling a hydrocarbonaceous, in particular oil-containing vapor at a temperature of e.g. about 300 to 1000°C, supplying the hydrocarbonaceous vapor expelled in the expulsion stage and/or in a gasification stage downstream of the expulsion stage to a processing stage, in which the same is further processed e.g. by cracking, coking and/or hydrotreating, separating the products obtained in the processing stage and withdrawing the same, introducing the solids left in the expulsion stage and/or in the gasification stage including the non-evaporated fractions of heavy hydrocarbons into a combustion stage, burning the heavy hydrocarbons left in the solids in the combustion stage at a temperature of e.g. about 600 to 1500°C, preferably e.g. about 1050 to 1200°C, recirculating hot solids from the combustion stage into the expulsion stage and/or the gasification stage, wherein the oxidizing atmosphere of the combustion stage is separated from the atmosphere of the expulsion stage and/or the gasification stage by means of a blocking device, and supplying water into the expulsion stage and/or the gasification stage.
Abstract:
The present invention relates to the production of metal oxide from metal salts, in particular from aluminum hydroxide, wherein the metal salt is preheated in a first preheating stage, precalcined in a second preheating stage and calcined to metal oxide in a fluidized-bed reactor, and wherein the product obtained then is cooled in at least one suspension heat exchanger and subsequently in a multi-stage indirect cooler. To reduce the energy demand of a calcining plant, fluidizing air is supplied to the reactor with a temperature of up to 150 °C, and before entering the first preheating stage the metal salt is at least partly supplied to a hydrate dryer in which it is indirectly heated with heat transfer medium from the first stage of the indirect cooler and dried.
Abstract:
A process for producing metal oxide from a metal salt includes supplying a first part of the metal salt to a hydrate drier so as to indirectly heat the first part of the metal salt in the hydrate drier using a heat transfer medium from a first stage of a multi-stage indirect cooler so as to dry the first part of the metal salt in the hydrate drier and so as to control a waste gas temperature of the process. A second part of the metal salt is guided as a partial stream past the hydrate drier. The metal salt is preheated in a first preheating stage and precalcined in a second preheating stage. The metal salt and a fluidizing gas having a temperature of 150° C. or less are supplied to a fluidized bed reactor so as to calcine the metal salt to form a metal oxide product. The metal oxide product is cooled in at least one suspension heat exchanger and then in the multi-stage indirect cooler.
Abstract:
When producing metal oxide from metal salts, the metal salt, in particular aluminum hydroxide, is dried and preheated in a first preheater (2) at a temperature of 100 to 200°C, precalcined in a second preheater (5) at a temperature of 300 to 400°C and then calcined in a reactor (8) at a temperature of 850 to 1100°C to obtain metal oxide, in particular alumina. After precalcination in the second preheater (5), a partial stream of the metal salt is branched off and supplied to a mixing tank (14), in which it is mixed with the metal oxide withdrawn from the reactor (8).
Abstract:
Die vorliegende Erfindung betrifft die Herstellung von Metalloxid aus Metallsalzen, insbesondere aus Aluminiumhydroxid, wobei das Metallsalz in einer Trockeneinrichtung getrocknet, in wenigstens einer Vorwärmstufe vorgewärmt und in einem Wirbelschichtreaktor zu Metalloxid kalziniert wird, und wobei das gewonnene Metalloxid dann abgekühlt wird. Um den Energiebedarf einer Kalzinieranlage zu verringern, wird das Metallsalz vor der Trocknung in wenigstens einem Filter gereinigt und in der Trockeneinrichtung gebildeter Dampf in den Filter zurückgeführt.
Abstract:
The present invention relates to the production of metal oxide from metal salts, in particular from aluminum hydroxide, wherein the metal salt is dried in a drying means, preheated in at least one preheating stage, and calcined to metal oxide in a fluidized-bed reactor, and wherein the metal oxide obtained then is cooled. To reduce the energy demand of a calcining plant, the metal salt is cleaned in at least one filter before being dried and steam formed in the drying means is recirculated into the filter.
Abstract:
Die vorliegende Erfindung betrifft die Herstellung von Metalloxid aus Metallsalzen, insbesondere aus Aluminiumhydroxid, wobei das Metallsalz in einer ersten Vorwärmstufe vorgewärmt, in einer zweiten Vorwärmstufe vorkalziniert und in einem Wirbelschichtreaktor zu Metalloxid kalziniert wird, und wobei das gewonnene Produkt dann in wenigstens einem Suspensionswärmetauscher und anschließend in einem mehrstufigen indirekten Kühler abgekühlt wird. Um den Energiebedarf einer Kalzinieranlage zu verringern, wird dem Reaktor Fluidisierungsluft mit einer Temperatur von bis zu 150°C zugeführt und das Metallsalz vor dem Eintritt in die erste Vorwärmstufe wenigstens teilweise einem Hydrattrockner zugeführt, in welchem es mit Wärmeträgermedium aus der ersten Stufe des indirekten Kühlers indirekt erwärmt und getrocknet wird.