Abstract: A method for the production of nitric acid, comprising a step of oxidation of ammonia in the presence of a catalyst, comprising a step of monitoring the temperature of said catalyst by at least one contactless infrared sensor.

Abstract: A temperature swing adsorption (TSA) process for removing a target component from a gaseous mixture (111), said process being carried out in a plurality of reactors (101, 102, 103), wherein each reactor (101) performs the following steps: an adsorption step (a) wherein an input stream (111) of said gaseous mixture is contacted with a solid adsorbent selective for said target component, producing a first waste stream (112) depleted of the target component; a heating step (b) for regeneration of the loaded adsorbent providing a first output stream (115) containing the target component; a cooling step (c) of the regenerated adsorbent, said TSA process also comprising: i) a pre-cooling step (b1) before said cooling step (c), wherein the regenerated adsorbent is contacted with a waste stream (137) which is produced by the adsorption step (a) of another reactor (103) and a second output stream (116) of the target component is produced; ii) a pre-heating step (a1) after said adsorption step (a) and before said heati

Abstract: A process for producing ammonia synthesis gas from a hydrocarbon-containing feedstock, with steps of primary reforming, secondary reforming with an oxidant stream, and further treatment of the synthesis gas including shift, removal of carbon dioxide and methanation, wherein the synthesis gas delivered by secondary reforming is subject to a medium-temperature shift (MTS) at a temperature between 200 and 350.degree. C., and primary reforming is operated with a steam-to-carbon ratio lower than 2. A corresponding method for revamping an ammonia plant is disclosed, where an existing HTS reactor is modified to operate at medium temperature, or replaced with a new MTS reactor, and the steam-to-carbon ratio in the primary reformer is lowered to a value in the range 1-5-2, thus reducing inert steam in the flow rate trough the equipments of the front-end.

Abstract: A process for producing ammonia and a derivative of ammonia from a natural gas feed comprising conversion of natural gas into a make-up synthesis gas; synthesis of ammonia; use of said ammonia to produce said derivative of ammonia, wherein a portion of the natural gas feed is used to fuel a gas turbine; power produced by said gas turbine is transferred to at least one power user of the process, such as a compressor; heat is recovered from exhaust gas of said gas turbine, and at least part of said heat is recovered as low-grade heat available at a temperature not greater than 200° C., to provide process heating to at least one thermal user of the process, such as CO2 removal unit or absorption chiller; a corresponding plant and method of modernization are also disclosed.

Abstract: Vertical reactor (1) for chemical reactions, comprising a tube heat exchanger (6) immersed in a catalytic bed (5), wherein said tube exchanger (6) comprises a plurality of straight tube bundles (6.1, 6.2) with respective tube plates for feeding (9.1, 9.2) and collecting (10.1, 10.2) the heat exchange fluid, and wherein the tube bundles and the respective tube plates are vertically staggered so as to allow access to the shell side.

Abstract: A process for producing ammonia synthesis gas from a hydrocarbon-containing feedstock in a front-end, comprising the steps of steam reforming of said feedstock, obtaining a synthesis gas comprising hydrogen, carbon monoxide and carbon dioxide; a treatment of said synthesis gas including shift of carbon monoxide and subsequent removal of carbon dioxide, wherein the shift of the synthesis gas includes high-temperature shift with an iron-based catalyst and at a temperature greater than 300° C. and the global steam-to-carbon ratio of the front end is 2.6 or less; a corresponding plant and a method for revamping a front-end of an ammonia plant are also disclosed.

Abstract: Combined apparatus (1) for the synthesis of urea from ammonia and carbon dioxide, comprising an internal wall (3) which delimits two coaxial zones (4) inside the apparatus, operating respectively as reaction (4) and condensation (5) zones, and optionally also comprising a stripping zone and/or a scrubber integrated in the same apparatus.

Abstract: A process for production of a granular urea product in a fluidized-bed where: small droplets (10) of fresh urea melt are contacted with a cooling medium to form solid particles, said solid particles (11) are contacted with droplets of urea melt (12) which are larger than said germ particles, the solid particles and said droplets forming together larger solid particles (13), and said solid particles further increasing their size step by step and upon contact with droplets of urea melt, until the solid particles reaches a given size, and said solid particles are then subject to a further growing process by contact with liquid droplets now smaller than the solid particles, until a desired size of the granular product is reached.

Abstract: A shell-and-tube stripper for carbamate decomposition and ammonia recovery from a urea solution comprising a bundle of heated tubes, said tubes being fed with said urea solution and carbon dioxide as stripping medium, the urea solutions forming a liquid falling film on the internal surface of the tubes and the carbon dioxide forming a counter-current gaseous flow; said tubes comprise an external layer made of super austenitic or super duplex stainless steel and an internal layer made of zirconium, said internal layer reaching temperatures higher than 220° C.

Abstract: 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.

Abstract: Reactor for the synthesis of melamine from urea, in accordance with the high-pressure non-catalytic process, comprising: a vertical reactor body (1), at least one inlet (2) for the urea melt, a set of heating elements (3), and a central duct (7), said set of heating elements (3) being arranged inside said central duct.

Abstract: 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.

Abstract: Process for making a hydrogen-containing synthesis gas (105) from a hydrocarbon feedstock (101), comprising the reforming of said hydrocarbon feedstock and purification of raw synthesis gas, said purification comprising shift conversion of carbon monoxide into carbon dioxide and subsequent absorption of carbon dioxide into an absorbing medium (7a, 14), resulting in a stream of a CO2-rich medium (5), and regeneration of said medium with recovery of CO2 absorbed therein, wherein said raw synthesis gas (102) is produced by the reforming step at a pressure of at least 45 bar, said regeneration of the CO2-loaded medium includes a step of chemical regeneration and the CO2-loaded medium has a temperature of at least 150° C. during said chemical regeneration.

Abstract: Tube-bundle heat exchange unit (1) for internals of heat exchangers or reactors, comprising: at least one tube bundle (2); a plurality of baffles (3) associated with said tube bundle and defining through-openings according to a predefined arrangement, each opening being passed through by one of more tubes of the tube bundle, and a shell (6) which surrounds said tube bundle and said baffles, wherein the assembly of the tube bundle and the shell can be disassembled and the shell is structurally collaborating with the tube bundle through said baffles.

Abstract: Method for reducing the content of nitrogen oxides NOx and nitrous oxide N2O in an input gas, comprising the steps of: treating said gas with a first amount of a NOx reducing agent in a first de-NOx catalytic bed; treating the effluent of said first de-NOx catalytic bed in at least one de-N2O catalytic bed for removal of N2O; treating the effluent of said at least one de-N2O catalytic bed with a second amount of a NOx reducing agent in a second de-NOx catalytic bed.

Abstract: A process for producing ammonia synthesis gas from a hydrocarbon-containing feedstock, with steps of primary reforming, secondary reforming with an oxidant stream, and further treatment of the synthesis gas including shift, removal of carbon dioxide and methanation, wherein the synthesis gas delivered by secondary reforming is subject to a medium-temperature shift (MTS) at a temperature between 200 and 350° C., and primary reforming is operated with a steam-to-carbon ratio lower than 2. A corresponding method for revamping an ammonia plant is disclosed, where an existing HTS reactor is modified to operate at medium temperature, or replaced with a new MTS reactor, and the steam-to-carbon ratio in the primary reformer is lowered to a value in the range 1-5?2, thus reducing inert steam in the flow rate trough the equipments of the front-end.

Abstract: Process for the synthesis of ammonia from a make-up gas containing hydrogen and nitrogen, said process comprising: generation of a synthesis gas (8) containing hydrogen and nitrogen in a molar ratio lower than 3, inside a front-end section (2); a first cryogenic purification, designed to remove nitrogen and raise said molar ratio; conversion of the synthesis gas into ammonia (13) inside a high-pressure synthesis loop (6), with extraction from said loop of a purge stream (14) containing hydrogen and inert gases; wherein at least a portion of said purge stream (14) undergoes a further purification in order to recover at least part of the hydrogen contained therein, obtaining at least one stream (15, 15a, 16, 18) containing recovered hydrogen which is recycled to the process.

Abstract: A process for removing hydrogen and methanol from a CO2 stream which contains hydrogen and methanol as contaminants, wherein hydrogen and methanol are removed by contacting the CO2 stream with a catalyst which oxidizes hydrogen to water and methanol to carbon dioxide, obtaining a purified CO2 stream.

Abstract: A method for revamping a CO2 removal section for removing carbon dioxide from a hydrogen-containing synthesis gas, wherein the CO2 removal section comprises an absorption section (2) wherein carbon dioxide is transferred to an absorbing solution and a stripping tower (3) for regeneration of the CO2-loaded solution, said stripping tower comprising an upper zone (4) where a first gaseous CO2 stream (10) and a partially regenerated semi-lean solution (11) are produced, and a lower zone (5) acting as a stripping zone where a second gaseous CO2 stream (12) and a lean regenerated solution are produced, the second CO2 stream (12) being a substantially pure stream containing less hydrogen and impurities than the first CO2 stream, and wherein the method of revamping provides the installation of sealing means (16) inside the stripping tower (3), arranged to isolate said second gaseous CO2 stream (12) from the first stream (10), so that the second stream (12) can be exported separately.

Abstract: A combined reactor and condenser for the synthesis of urea from ammonia and carbon dioxide, including a condenser section coupled to a reaction section, comprising inputs directed to said condenser section for a gaseous stream comprising ammonia and carbon dioxide and for a solution containing ammonium carbamate and liquid ammonia, and wherein the effluent of the condenser section is sent to the reaction section; the reaction section comprises a plurality of compartments and a plurality of mixers, at least one inside each of said compartments.