In a cooled axial/radial flow converter, in which process gas passes from an outer annulus via a catalyst bed to an inner center tube, the catalyst bed is divided into identical modules stacked on top of each other. The process gas reaches the catalyst through openings facing the outer annulus, passes axially down the catalyst bed of each module, leaves the module through collectors in the bottom thereof, and flows to the center tube. The catalyst bed is cooled by cooling panels, in which the process gas is pre-heated to the reaction temperature, while at the same time the heat of reaction is partly removed from the catalyst bed. The converter is especially suitable as ammonia converter.

A furnace for performing an endothermic process, comprising tubes containing a catalyst for converting a gaseous feed, wherein tubes are positioned in rows inside the furnace, wherein burners are mounted between the tubes and between the tubes and the furnace walls parallel to the tubes rows, and wherein the burners rows and the tubes rows are ended by end walls and are divided into sections with, on each row of tubes, the distance from a wall end tube to the end wall being T2W, the distance between two adjacent inner tubes in a section being T2T, and the distance between two symmetry end tubes of two adjacent sections being T2S, wherein the tubes in the rows are arranged in such a way that the ratios T2T/T2W and T2T/T2S are greater than 0.5 and smaller than 2 thus limiting the differences in the heat transfer to the outer tubes (wall end tubes and symmetry end tubes) with respect to the inner tubes and reducing the temperature difference between outer tubes and inner tubes.

The present disclosure provides systems and methods for producing olefins via an oxidative coupling of methane (OCM) process. The systems and methods may comprise the use of a staged process comprising at least one non-adiabatic section that is in thermal communication with a heat transfer medium and at least one substantially adiabatic section. The systems and methods may also comprise the use of a diluent stream which may improve methane conversion in an OCM reactor and an ethylene/ethane ratio in a post-bed cracking unit. The methods and systems may further comprise injecting oxygen (O.sub.2) and a paraffin into a gas stream containing a radical transfer agent to provide a reaction mixture. The reaction mixture may be held in a vessel for a time period greater than an auto-ignition delay time (AIDT), such that the reaction mixture may ignite to liberate heat and convert to a product mixture comprising olefins.

In a cooled axial/radial flow converter, in which process gas passes from an outer annulus via a catalyst bed to an inner centre tube, the catalyst bed is divided into identical modules stacked on top of each other. The process gas reaches the catalyst through openings facing the outer annulus, passes axially down the catalyst bed of each module, leaves the module through collectors in the bottom thereof, and flows to the centre tube. The catalyst bed is cooled by cooling panels, in which the process gas is pre-heated to the reaction temperature, while at the same time the heat of reaction is partly removed from the catalyst bed. The converter is especially suitable as ammonia converter.

The present invention relates to a method for producing unsaturated aldehydes and unsaturated carboxylic acids. According to the present invention, a method for producing unsaturated aldehydes and unsaturated carboxylic acids which can impart activity and control temperature independently in fixed catalyst layer zones in a shell-and-tube reactor, thereby exhibiting improved yield and operation stability, is provided.

Processes and systems for producing olefins, including: dehydrogenating a first n-alkane to produce a first effluent; and dehydrogenating at least one of a first isoalkane or a second n-alkane to produce a second effluent. The first and second effluents may be compressed and fed to a common separation train to separate the effluents into two or more fractions. In some embodiments, each of the first and second dehydrogenation reaction zones may include two reactors, one reactor in each of the reaction zones operating in a dehydrogenation cycle, one operating in a regeneration cycle, and one operating in a purge or evacuation/reduction cycle. Operation of the reactors in the dehydrogenation cycle is staggered, such that the purge cycle, regeneration cycle, or evacuation/reduction cycle of the reactors may not overlap.

Processes and systems for producing olefins, including: dehydrogenating a first n-alkane to produce a first effluent; and dehydrogenating at least one of a first isoalkane or a second n-alkane to produce a second effluent. The first and second effluents may be compressed and fed to a common separation train to separate the effluents into two or more fractions. In some embodiments, each of the first and second dehydrogenation reaction zones may include two reactors, one reactor in each of the reaction zones operating in a dehydrogenation cycle, one operating in a regeneration cycle, and one operating in a purge or evacuation/reduction cycle. Operation of the reactors in the dehydrogenation cycle is staggered, such that the purge cycle, regeneration cycle, or evacuation/reduction cycle of the reactors may not overlap.

A monolith-type reactor includes a porous support body, a plurality of first cells through which a raw material gas flows, a plurality of second cells through which the sweep gas flows, separation membranes, and a catalyst. The first cells pass through the porous support body in a first direction. The second cells extend in the porous support body in the first direction. The separate membranes are respectively formed on inner peripheral surfaces of the first cells and permeable to a product of the conversion reaction. The catalyst is arranged inside the separation membranes, and promotes the conversion reaction. In a cross section taken along a second direction perpendicular to the first direction, the average cross-sectional area of the first cells is larger than the average cross-sectional area of the second cells.

A tubular reactor that produces maleic anhydride from a gas mixture containing n-butane and oxygen includes a first reaction zone including an inlet for the gas mixture and a second reaction zone including an outlet for a reaction gas mixture, a plurality of tubes extending in an axial direction through the first and second reaction zones, a temperature control system, configured for controlling a reaction temperature in each of the reaction zones independently, includes a heat transfer system for each of the reaction zones configured for controlling the temperature of a liquid coolant flowing through one of the reaction zones, and a circulation pumping system configured for controlling flow conditions of the liquid coolant flowing through the reactor and one of the heat transfer systems, and a preheating arrangement configured for preheating the gas mixture such that the gas mixture enters the first reaction zone at a predefined inlet temperature.

Processes and systems for producing olefins, including: dehydrogenating a first n-alkane to produce a first effluent; and dehydrogenating at least one of a first isoalkane or a second n-alkane to produce a second effluent. The first and second effluents may be compressed and fed to a common separation train to separate the effluents into two or more fractions. In some embodiments, each of the first and second dehydrogenation reaction zones may include two reactors, one reactor in each of the reaction zones operating in a dehydrogenation cycle, one operating in a regeneration cycle, and one operating in a purge or evacuation/reduction cycle. Operation of the reactors in the dehydrogenation cycle is staggered, such that the purge cycle, regeneration cycle, or evacuation/reduction cycle of the reactors may not overlap.