Covestro Deutschland Ag

Covestro Intellectual Property Gmbh & Co. Kg

Jürgen Spriewald

Stefan Wershofen

Thomas Knauf

Dietmar Wastian

Volker Michele

Peter Plathen

Dirk Manzel

Richard Adamson

Anke Hielscher

Ricardo Serra

Achim Wildermuth

Enke Liu

The present invention relates to a process for producing isocyanates in process chains, each of which produce an isocyanate end product via at least one intermediate product, wherein the heat energy liberated in a first production plant in a heat-emitting operation of producing an intermediate product, an isocyanate end product or a catalyst required for a substep of the process chain (first chemical product) is at least partly utilized for generating vapour, in particular water vapour, having a pressure of 1.31 barto 1.91 barand a temperature of 107&#xb0; C. to 119&#xb0; C. and the thus generated vapour is employed for performing a heat-consuming operation in the preparation of another chemical product (second chemical product) in a second production plant.

Process for producing isocyanate and at least one further chemical product in an integrated production

The invention relates to a method for an economically and technically improved embodiment of a production interruption in a production method for isocyanates by phosgenation of the corresponding amines, in which the entire production plant is not closed while one or more parts of the plant is taken out of operation, rather the input materials and/or reaction products available in the production plant are recirculated through at least one part of the plant that has not been taken out of operation. The invention further relates to a plant for producing isocyanates and to a method for operating a plant for producing isocyanates.

Method for producing isocyanates

The invention relates to a method for producing isocyanates, according to which exhaust flows provided for the combustion are guided through an adsorption device before being supplied into the exhaust gas combustion process, and are thereby depleted of solvent, the adsorption device comprising at least two adsorption units connected in parallel, which are alternately (i) exposed to the at least one exhaust flow and (ii) regenerated with water vapor, where, during method step (i), an exhaust flow depleted of solvent is obtained, and during method step (ii), a flow containing water and solvent is obtained, the solvent proportion of which is recycled into a method for producing isocyanates.

A divided wall column includes: a column shell; a divided wall provided vertically inside the column shell, defining a divided wall section between an upper edge and a lower edge of the divided wall; and a liquid distributor provided within the divided wall section. The liquid distributor is fixed only to the column shell but not to the divided wall. By using the divided wall column, a defect involved in conventional divided wall columns, i.e. a maldistribution of fluid over mass transfer elements caused by a manufacturing defect of the divided wall resulted from its manufacturing process and/or a deformation thereof under operation conditions, can be minimized or even avoided.

Divided wall columns

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Kölln-Reisiek, Germany

Jürgen Spriewald