Abstract:
The present invention relates to a reactor system (1) comprising a reactor 3, at least one cooler (5) connected to the reactor (3), at least one pump (7) for circulating at least some of a liquid heat-transfer medium (9), wherein the pump (7) is connected to the reactor (3) and/or the at least one cooler (5), and a container (11) for collecting the liquid heat-transfer medium (9), wherein the container (11) is connected to the reactor (3) and/or the at least one cooler (5), wherein the container (11) is disposed substantially below the reactor (3) and/or the at least one cooler (5). Moreover, the use of the reactor system (1) according to the invention for carrying out exothermic reactions is described.
Abstract:
The invention relates to an oxidation catalyst comprising at least one inorganic, oxidic or ceramic, shaped support body having a BET surface area of less than 0.5 m2/g, based on the support, which is at least partly coated with a catalytically active multielement oxide, the catalyst being precious metal-free and the shaped support body having the form of a saddle whose saddle surface is curved oppositely in the two principal directions, to a process for producing it, to its use in various catalytic gas phase oxidations, and to corresponding processes for catalytic gas phase oxidation.
Abstract:
The present invention relates to a method of redissociating Michael adducts of acrylic acid present in a liquid F in a redissociation apparatus comprising at least one separating column K, an evaporator V and a pump P, wherein, in the event of an unwanted rise in the viscosity of the residue R in the bottom space of the separating column K, the feed of the liquid F into the redissociation apparatus is stopped, the residue R in the bottom space of the separating column K is diluted and cooled with a solvent 1, and the bottom space of the separating column K is emptied.
Abstract:
Process for inhibiting the undesired free-radical polymerization of acrylic acid present in a liquid phase P, wherein the acrylic acid content of P is at least 10% by weight, the liquid phase P comprises in the range from 25 to 1000 ppmw of glyoxal based on the weight of the acrylic acid present in P and the liquid phase P is admixed with furfural in an amount that results in a furfural content in the range from 25 to 1000 ppmw based on the weight of the acrylic acid present in P. Liquid phase P, wherein the acrylic acid content of P is at least 10% by weight and the liquid phase P comprises in the range from 25 to 1000 ppmw of glyoxal and in the range from 25 to 1000 ppmw of furfural in each case based on the weight of the acrylic acid present in P.
Abstract:
The present invention relates to a column (1) for thermal treatment of fluid mixtures, having a cylindrical, vertically aligned column body (2) which forms a column cavity (3), having a sequence of vertically spaced-apart dual-flow mass transfer trays (8) which are mounted in the column cavity (3) and which have orifices for passage of liquid and gas in countercurrent, and having at least one gas entry orifice (5) disposed below the lowermost of the sequence of dual-flow mass transfer trays (8). It is a characteristic feature of the column of the invention that a gas distribution tray (9) which is disposed between the lowermost of the sequence of dual-flow mass transfer trays (8) and the gas entry orifice (5) has orifices (32) for vertical passage of gas which can be introduced into the column cavity (3) via the gas entry orifice (5), the orifices (32) being formed so as to bring about equal gas distribution over the column cross section. The invention further relates to a process for thermal treatment of fluid mixtures in such a column (1).
Abstract:
The present invention relates to a process for treating secondary components obtained in acrolein and/or (meth)acrylic acid production, comprising the steps of: a) contacting at least one wastewater stream (201) comprising at least a portion of the water of reaction removed in a first stage of a saturation column (101) with at least one process offgas stream (203), b) introducing energy by means of a first heat transferer (103) provided in a first saturation circuit (301) into the first stage of the saturation column (101), c) partly vaporizing the wastewater stream (201) into the process offgas stream (203) and passing the combined gas stream (205) into a second stage of the saturation column (101), d) drawing off a concentrated wastewater stream (207) from the bottom (1011) of the first stage of the saturation column (101) and feeding it to the top (1023) of the second stage of the saturation column (101), e) introducing energy by means of a second heat transferer (105) provided in a second circuit (303) into the second stage of the saturation column (101), f) partly vaporizing the concentrated wastewater stream (207) into the combined gas stream (205) to obtain an offgas stream (209), g) superheating the offgas stream (209), after it has been saturated, in a third heat transferer (113) to obtain a superheated offgas stream (211) and h) transferring the offgas stream (209) or the superheated offgas stream (211) from the saturation column (101) to a thermal aftertreatment. The present invention further relates to a plant (1) for treating the secondary components obtained in acrolein and/or (meth)acrylic acid production.
Abstract:
The present invention relates to a column (1) for thermal treatment of a fluid, having a cylindrical, vertical column body (2) which forms a column cavity (3), and a mass transfer tray (4) which is disposed in the column cavity (3) and forms a collecting area (5). The inventive column (1) is characterized by a circulation device (9) having at least one drain orifice (10) formed in the column body (2) above the collecting area (5), a circulation line (11) in fluid connection with the drain orifice (10) and at least one recycling orifice (14; 14-1 to 14-3) which is in fluid connection with the circulation line (11) and is formed in the column body (2) above the collecting area (5). The invention also relates to a thermal separating process in which such a column (1) is used. In this separating process, a gas ascends within the column and a liquid descends within the column, said gas and/or liquid especially comprising (meth)acrylic monomers.
Abstract:
The present invention relates to a system (1) for operating a liquid gas evaporator (3), comprising an evaporator (3) for evaporating a liquid gas into its gaseous aggregation state, a trough (5) carrying the evaporator (3), a housing (7) which surrounds the evaporator (3) on three sides and which terminates flush with the trough (5), at least one detector (9) which is sensitive to the liquid gas and its gaseous aggregation state and which is arranged in the trough (5), a line (11) for the distribution of vapor D, which is provided on the fourth, non-housed side of the evaporator (3) and which is arranged at that margin of the trough (5) which is not closed off by the housing (7), a feed (13), connected to the line (11), for the vapor D, and a regulating valve (15) provided on the feed (13) and connected to the detector (9) and at least one shut-off valve (17). The present invention relates furthermore, to a method for operating a liquid gas evaporator (3).
Abstract:
The present invention relates to an apparatus (1) for separation of a target product from a liquid phase P comprising the target product, comprising at least one primary space (3) for a heat transfer medium W, at least one first feed unit (5a) and one first removal unit (5b) for the heat transfer medium W, at least one secondary space (7) for the liquid phase P, at least one second feed unit (9) for the liquid phase P, at least one crystallization surface (13) which divides the primary space (3) and the secondary space (7), at least one second removal unit (15) for the target product and at least one application unit (11) for a liquid phase P0 essentially directly to the crystallization surface (13) or the surfaces of lines that conduct the heat transfer medium W. The present invention further relates to a process for removing a target product from a liquid phase P comprising the target product.
Abstract:
The present invention describes a system (1) for recovering liquid or free-flowing chemicals in a chemical plant (3), comprising at least two plant sections (3a, 3b), for each plant section (3a, 3b) at least one connecting device (5a, 5b) arranged at the lowest point, at least one common collecting line (7) which runs beneath the connecting devices (5a, 5b) and connects them to one another, at least one collecting vessel (9) arranged at the same height as or higher than the at least two plant sections (3a, 3b) and above the collecting line (7), at least one pump (11) provided in the collecting line (7) between the connecting devices (5a, 5b) and the collecting vessel (9) for drawing off the at least one liquid or free-flowing chemical combined in the collecting line (7) and introducing it into the collecting vessel (9).