A tray support insert and method of use for supporting one or more trays within a reactor chamber. The tray support insert includes at least one annular member which rests upon a support shoulder within the reactor chamber.

The present application provides a composite material that comprises a solid and solid-supported non-polymeric switchable moiety, wherein the switchable moiety comprises a functional group that is switchable between a first form and a second form, said first form being neutral and hydrophobic, and said second form being ionized and hydrophilic. The composite material converts to, or is maintained in, said second form when the switchable moiety is exposed to CO.sub.2 at amounts sufficient to maintain the ionized form. The composite material converts to, or is maintained in, said first form when CO.sub.2 is removed or reduced to an amount insufficient to maintain the ionized form. CO.sub.2 is removed or reduced by exposing the composite material to heat and/or a flushing inert gas such as N.sub.2, Ar, or air. Envisioned uses of these composite materials includes removing water from non-aqueous solvents, removing water vapor from gaseous mixtures, and cleaning industrial reaction vessels and/or pipelines.

A method of revamping vertical converters having a bolt-on flanged pressure shell extension for housing an internal heat exchanger is performed by replacing an existing pressure shell extension with a larger pressure shell extension for housing a plurality of internal heat exchangers.

An integrated process, suitable for use in a new or retrofitted plant, produces an olefin or di-olefin via the dehydrogenation of an appropriate C3-C4 hydrocarbon feed includes (1) contacting the feed and a dehydrogenation catalyst having a Geldart A or Geldart B classification in a fluidized bed at a temperature from 550? C. to 760? C. and a pressure from about 41.4 to about 308.2 kPa (about 6.0 to about 44.7 psia) and a catalyst to feed ratio, w/w, from 5 to 100 to form a dehydrogenate product; separating the dehydrogenate product and unreacted starting feed mixture from a portion of the catalyst by means of a cyclonic separation system; reactivating the catalyst in a fluidized regenerator by combustion at 660? C. to 850? C., followed by contact with an oxygen-containing fluid at 660? C. or greater, and returning the catalyst to the dehydrogenation reactor; (2) compressing the product mixture to form a compressed product mixture; and (3) fractionating the compressed product mixture to form a product stream including at least the target olefin or di-olefin. The integrated process offers increased plant capacity, improved economics, and reduced environmental impact in comparison with other known and conventional processes.

Plant for the synthesis of urea, comprising: a synthesis section comprising at least one reactor, a compressor for supplying CO.sub.2 to said synthesis section, a gas turbine for the operation of said CO.sub.2 compressor and a heat recovery steam generator; the heat source of said heat recovery steam generator consists of the exhaust gases of said gas turbine, and at least one steam flow produced by said heat recovery steam generator is used as heat source for at least one component of said urea plant.

The present invention provides a method for increasing the capacity of a urea production complex, the method comprising a step of adding to an existing urea production complex a CO.sub.2 production unit, which unit employs a CO.sub.2 production method comprising: i) subjecting a hydrocarbon feed to short contact time catalytic partial oxidation (SCT-CPO) to produce a first gas mixture comprising H.sub.2, CO and CO.sub.2, ii) subjecting said first gas mixture to a water gas shift reaction yielding a second gas mixture, iii) separating CO.sub.2 from said second gas mixture yielding a purified CO.sub.2 stream and a hydrogen containing stream and subsequently iv) reacting said purified CO.sub.2 stream with ammonia from the ammonia production unit to produce urea. The invention also provides a urea production complex realized by the application of this method and a urea production method.

Disclosed is a urea plant wherein, in deviation from conventional plants, a high-pressure synthesis section is operated with two different pressures. The synthesis section comprises a reactor, which is operated under a first high pressure. The synthesis section also comprises a stripper and a condenser, both operated at substantially the same second high pressure. In accordance with the invention, the first pressure is substantially higher than the second pressure. The disclosed plant particularly comprises a compression unit capable of converting a pressure difference into work, or more specifically, mechanical energy for compression. This compression unit is positioned between a liquid outlet of the condenser and a liquid inlet of the reactor, and in fluid communication therewith. In order to make use of a pressure drop (expansion as a result of a liquid being depressurized), said compression unit is configured to obtain compression energy from one or more events in the urea production process (i.e., at one or more points in the urea production plant), at which a loss of energy occurs, such as decompression of a high energy stream. Typically, the compression unit is thereby configured to utilize mechanical energy recovered from a decompression unit positioned downstream of the stripper and upstream of the recovery section.

The disclosure pertains to a coupled plant process for the production of urea and melamine, with a urea synthesis section with HP CO.sub.2 stripping, and with a part of the CO.sub.2 feed supplied to a recovery section.

Reactor (1) for catalytic chemical reactions, comprising: a partially open outer vessel (2) comprising a manhole (6) for accessing to the interior, and at least one internal wall (5) comprising a plurality of panels (5.1, 5.2, . . . 5.n) assembled inside the vessel (2) so as to form said wall (5); the panels are flexible and deformable so that they may be inserted through said manhole (6), and the resulting wall (5) is not self-supporting and rests against a load-bearing wall (7) of the reactor.

Reactor (1) for catalytic chemical reactions, comprising: a partially open outer vessel (2) comprising a manhole (6) for accessing to the interior, and at least one internal wall (5) comprising a plurality of panels (5.1, 5.2, . . . 5.n) assembled inside the vessel (2) so as to form said wall (5); the panels are flexible and deformable so that they may be inserted through said manhole (6), and the resulting wall (5) is not self-supporting and rests against a load-bearing wall (7) of the reactor.