Abstract:
A compact endothermic reaction apparatus employing metallic reaction tubes (28; 152) in a close-pack arrangement using offset nozzle tubes (90; 167) and an air distribution plate (68; 160) for introducing fuel and air into a combustion chamber to produce long and thin flames thereby to avoid excessive localized heating of the reaction tubes and provide high reaction tube life expectancy. Also, excessive localized heating of the reaction tubes at the inlet ends of exhaust tubes (94; 172) is eliminated and provision is made for preventing buckling of individual reaction tubes thatr may be subjected to higher than average reaction tube temperatures.
Abstract:
A heat exchange catalytic process and reactor of the shell-and-tube type having a plurality of tubes extending longitudinally through the shell from a tube fluid inlet region to a tube fluid outlet region and baffles extending transversely across the shell dividing the shell between said inlet and outlet regions into at least three heat exchange zones through which each tube passes in sequence in heat exchange with that zone. A shell fluid is passed through the heat exchange zones in heat exchange with the tube fluid passing through the tubes. Transfer passages are provided connencting the heat exchange zones and are disposed so that the shell fluid passes through the second zone before or after it has passed through both the first and third zones. A particulate catalyst is disposed in either the shell heat exchange zones or, preferably, the tubes. The process utilises a heat exchange medium, particularly water, that does not change state under the prevailing conditions and is preferably fed to the shell heat exchange zones while the reactant stream passes through the catalyst disposed in the tubes. The process is particularly applicable to the selective hydrogenation of acetylenes in the presence of olefins.
Abstract:
A catalytic reactor for endothermic reactions is disclosed. The catalyst is located in a housing (13) made of refractory material, and at least a tubular catalyst vessel (10) is arranged inside the housing (13). In order to obtain a catalytic reactor that avoids thermal damages to the reactor vessel without requiring costly construction measures nor undesirable increases in the amounts of exhaust gasses, as well as the resulting inconveniences for the energy efficiency of the fuels used, several mutually spaced catalyst vessels (10) are arranged in the housing (13), a plurality of burners (15) is arranged in the housing (13) in such a way that the catalyst vessels (10) lie between the burners (15) and the flame area of the burners (15) lies in the area of the heat dissipators (16) in order to ensure a non-adiabatic combustion.
Abstract:
A tubular pressurized catalytic hydrocarbon converter provided with a cylindrical casing (1) containing vertical gas exhaust pipes (4) around which are arranged reaction tubes (2) which are coaxially placed in sleeves (3). The lower portions of these tubes are connected to the vertical pipes by 'pig-tails' and have a novel design since the aim is to increase the converter's reliability and working life by eliminating reaction tube deformation and facilitating 'pig-tail' assembly and maintenance. To this end, the converter is provided with a transverse wall attached to the lower ends of the sleeves and provided with openings in which the lower ends of the tubes and vertical pipes are freely inserted. It is also provided with plates (7) having movable covers (8) and attached to the lower ends of the vertical pipes which are in turn connected to the 'pig-tails'.
Abstract:
Es wird ein Verfahren zur Durchführung einer endother men Reaktion, beschrieben bei dem ein zu dehydrierender Einsatz durch einen einen Katalysator aufweisenden Reaktor geleitet und der Katalysator nach Desaktivierung regeneriert wird. Um ein derartiges Verfahren mit weniger apparativem und Energieaufwand betreiben zu können, wird vorgeschla gen, daß ein direkt befeuerter Reaktor verwendet und der Einsatz unverdünnt durch diesen Reaktor geleitet wird.
Abstract:
A single pass, shell and tube reactor which is designed for downflow of reactant fluid in tubes containing contact material is improved to allow more than one downflow pass of fluid through the tubes by providing upper and lower vertically aligned partition members to divide the upper and lower tube end chambers into isolated compartments and by using an empty tube to allow upflow communication between adjacent compartments. In a two compartment configuration, the upper and lower tube end chambers are each partitioned in half, but the lower partition member has a screened port to allow fluid from the first compartment to reach, and move upwardly through, an empty tube(s) in the second compartment which is isolated from the other tubes in the second compartment at its bottom end but not at its top end.
Abstract:
Improved performance is obtained in a multi-tube reactor for oxidation of ethylene to ethylene oxide by providing a distribution zone for the coolant located downstream of the catalyst and a contiguous cooling zone. The effluent gases from the oxidation are cooled in the cooling zone by a fluid, which has been only slightly preheated and distributed uniformly in the distribution zone by contact with tubes in which the effluent gases are in low-turbulence flow. Uniform distribution of the coolant provides substantially equal cooling of the effluent gases in each tube, thus minimizing the variation in effluent gas temperature among the tubes. Preferably, the tubes in the cooling section are packed with inert particles to facilitate heat transfer, while the tubes are empty in the distribution section to reduce heat transfer.
Abstract:
A temperature control system controls the temperature of an olefin oxidation reactor (10) by measuring various parameters in the reactor and in flow lines to and from the reactor, and using these parameters with known quantities for specific heat of the feed and effluent and heats of vaporization and reaction, to calculate a coolant flow rate set point. Parameters relating to the heat balance with regard to a desired olefin oxide product and undesired carbon dioxide products are utilized for correct control. Equipment is also provided for ascertaining the state of a catalyst used in the reaction. Circuit components are provided for obtaining changes in flow rates, temperatures and concentrations to calculate a change in coolant flow rate as well as the steady state effluent flow rate quantity to improve the system response to start up, shut down and transient conditions.
Abstract:
The geometry of the reactor is tailored to increase the heat transfer capacity of the initial sections of the reactor columns (12a) where the greatest heat is generated. This is accomplished by reducing the inner diameter of the initial column sections (12a) relative to that of the final column sections (12c) and by increasing the rate of heat transfer from to the coolant proximate the initial column sections (12a) by increasing the velocity of coolant surrounding the initial column sections. Further, the coolant flow is directed in a direction perpendicular to the axis of each column by spaced, laterally offset baffles (68), (70).
Abstract:
A vertical catalytic reactor for steam reforming a reactor fuel into a product gas, the catalytic reactor containing a catalyst forming a catalyst bed. If the catalytic reactor material has a thermal coefficient of expansion greater than the catalyst, then the catalytic reactor experiences problems due to thermal cycling. During the start-up of the catalytic reactor, the temperature increase causes the catalytic reactor to expand more than the catalyst, thus, the catalyst slumps within the catalytic reactor. During the shut-down of the catalytic reactor, the temperature decrease causes the catalytic reactor to contract and crush the slumped catalyst. The catalytic reactor incorporates a design (100) for reducing catalyst slumping and crushing.