Abstract:
PROBLEM TO BE SOLVED: To certainly and structurally simply assure that heat exchange medium flows downward around catalyst tubes and accordingly in parallel with a reaction mixture guided similarly downward via the catalyst tubes in a reactor having a bundle of catalyst tubes and an annular conduit into which the reaction mixture is guided via the catalyst tubes and the heat exchange medium is guided via a space surrounding the catalyst tubes and on which a jacket opening for feeding or discharging the heat exchange medium to both ends of the reactor by a single or a plurality of pumps is formed. SOLUTION: The pump has oblique impellers and a restriction gap in a longitudinal direction of a pump shaft is formed inside the heat exchange medium on discharge side of the pump for sealing and bearing the pump shaft and for reducing axial moves of the oblique impellers. COPYRIGHT: (C)2003,JPO
Abstract:
The invention relates to a multi-tube fixed-bed reactor and to the use of a reactor of this type for carrying out catalytic gas phase reactions, especially for carrying out exothermic or endothermic catalytic gas phase reactions such as producing phthalic anhydride (PSA), acrylic acid (AA), methacrylic acid (MAA), acrolein, maleic anhydride (MSA), glyoxal, phosgene, hydrogen cyanide or vinyl formamide (VFA). According to the invention, in the case of larger reactors where a considerable reaction heat is produced or required and must be dissipated as a result of the numerous reaction tubes (17), the ratio of tube distribution t to tube outer diameter d?a? is made dependant on the reactor diameter or the tube bundle diameter d?RBa?. If the outer diameter of the reaction tube bundle (18) is more than 4 metres, a ratio of tube distribution t to tube outer diameter d?a? of at least 1.3 is preferred.
Abstract:
The invention relates to a reactor (1) comprising a bundle of contact tubes (2). A heat-exchanging medium is guided through the area surrounding the contact tubes. Both ends of the reactor have annular ducts (3,4) with jacket orifices (5,6) for supplying or educting a heat-exchanging medium by means of at least one pump, optionally transferring the heat-exchanging medium or a partial current of the heat-exchanging medium via at least one external heat exchanger. The heat exchanging medium is fed to the lower annular duct (4) and is returned to the pump(s) via the upper annular duct (3). Deviating discs (7) alternately leave open a passage diameter at the centre or at the edge of the reactor. The lower annular duct (4) is split into two zones by means of a horizontal partition (8), said two zones communicating with each other via preferably homogeneously divided openings (9) with adjustable passage diameters.
Abstract:
The invention relates to a reactor (1) comprising a bundle of contact tubes (2). A heat-exchanging medium is guided through the area surrounding the contact tubes. Both ends of the reactor have annular ducts (3,4) with jacket orifices (5,6) for supplying or educting a heat-exchanging medium by means of at least one pump, optionally transferring the heat-exchanging medium or a partial current of the heat-exchanging medium via at least one external heat exchanger. The heat exchanging medium is fed to the lower annular duct (4) and is returned to the pump(s) via the upper annular duct (3). Deviating discs (7) alternately leave open a passage diameter at the centre or at the edge of the reactor. The lower annular duct (4) is split into two zones by means of a horizontal partition (8), said two zones communicating with each other via preferably homogeneously divided openings (9) with adjustable passage diameters.
Abstract:
A multitube fixed bed reactor and the use of such a reactor for carrying out catalytic gas-phase reactions, in particular for carrying out exothermic and endothermic catalytic gas-phase reactions such as the preparation of phthalic anhydride (PA), acrylic acid, methacrylic acid (MAA), acrolein, maleic anhydride (MA), glyoxal, phosgene, hydrocyanic acid or vinyl formamide (VFA). In a relatively large multitube reactor in which a large amount of heat of reaction is generated owing to the numerous catalyst tubes ( 17 ) and has to be removed, it is proposed that the ratio of tube spacing t to external tube diameter d a be made dependent on the reactor diameter or on the external tube bundle diameter d RBa . At an external diameter of the catalyst tube bundle ( 18 ) of more than 4 meters, a ratio of tube spacing d to external tube diameter d a of at least 1.3 is preferred.
Abstract:
The invention proposes a reactor (1) having a contact tube bundle (2) through whose space surrounding the contact tubes a heat-exchange medium circuit is passed, with ring lines (3, 4) at both ends of the reactor with jacket apertures (5, 6) for the supply and discharge of a heat-exchange medium by means of a pump via an external heat exchanger, where the heat-exchange medium is fed to the lower ring line (4) and is discharged to the heat exchanger via the upper ring line (3), and with baffle plates (7) which leave a passage cross section alternately in the reactor center and at the reactor edge. The upper (3) and lower (4) ring lines are each divided into an inner (11, 13) and an outer (12, 14) ring line by a cylindrical partition wall (8, 9), and the heat-exchange medium is fed to the outer lower ring line (14), via a region outside the reactor to the inner upper ring line (11), via the jacket apertures (5) of the latter to the region surrounding the contact tubes (2), via the jacket apertures (6) to the inner lower ring line (13) and subsequently via a region outside the reactor to the outer upper ring line (12).
Abstract:
The invention proposes a reactor (1) having a contact tube bundle (2) through whose space surrounding the contact tubes a heat-exchange medium circuit is passed, with ring lines (3, 4) at both ends of the reactor with jacket apertures (5, 6) for the supply and discharge of a heat-exchange medium by means of a pump via an external heat exchanger, where the heat-exchange medium is fed to the lower ring line (4) and is discharged to the heat exchanger via the upper ring line (3), and with baffle plates (7) which leave a passage cross section alternately in the reactor center and at the reactor edge. The upper (3) and lower (4) ring lines are each divided into an inner (11, 13) and an outer (12, 14) ring line by a cylindrical partition wall (8, 9), and the heat-exchange medium is fed to the outer lower ring line (14), via a region outside the reactor to the inner upper ring line (11), via the jacket apertures (5) of the latter to the region surrounding the contact tubes (2), via the jacket apertures (6) to the inner lower ring line (13) and subsequently via a region outside the reactor to the outer upper ring line (12).
Abstract:
A multitube fixed bed reactor and the use of such a reactor for carrying out catalytic gas-phase reactions, in particular for carrying out exothermic and endothermic catalytic gas-phase reactions such as the preparation of phthalic anhydride (PA), acrylic acid, methacrylic acid (MAA), acrolein, maleic anhydride (MA), glyoxal, phosgene, hydrocyanic acid or vinyl formamide (VFA). In a relatively large multitube reactor in which a large amount of heat of reaction is generated owing to the numerous catalyst tubes ( 17 ) and has to be removed, it is proposed that the ratio of tube spacing t to external tube diameter d a be made dependent on the reactor diameter or on the external tube bundle diameter d RBa . At an external diameter of the catalyst tube bundle ( 18 ) of more than 4 meters, a ratio of tube spacing d to external tube diameter d a of at least 1.3 is preferred.
Abstract:
In a reactor (1) which has a bundle of catalyst tubes (2) and in which a heat transfer medium is circulated through the space surrounding the catalyst tubes, with the ring lines (3, 4) at both ends of the reactor with openings (5, 6) through the wall for introduction or removal of a heat transfer medium by means of one or more pumps, where the heat transfer medium is introduced into the lower ring line (4) and is returned via the upper ring line (3) to the pump(s) and the heat transfer medium or a substream of the heat transfer medium may, if desired, be passed over one or more external heat exchangers, and with deflecting plates (7) which alternately leave free an open cross section in the middle of the reactor and at the edge of the reactor, the lower ring line (4) is divided by means of a horizontal dividing wall (8) into two regions between which material can pass via preferably uniformly distributed openings (9) having a regulatable open cross section.