A burner basket for an ammonia oxidation burner includes a gas-permeable bottom plate, with a side wall that is spaced apart from the bottom plate by a gap, and a retaining device covering the bottom plate and the gap for retaining particles of a bulk material that can be arranged in the burner basket. A fastening element is arranged on the bottom plate, by which the retaining device is fixed in place. An ammonia oxidation burner comprises a burner for oxidizing ammonia and a burner basket.

A burner basket for an ammonia oxidation burner includes a gas-permeable bottom plate, with a side wall that is spaced apart from the bottom plate by a gap, and a retaining device covering the bottom plate and the gap for retaining particles of a bulk material that can be arranged in the burner basket. A fastening element is arranged on the bottom plate, by which the retaining device is fixed in place. An ammonia oxidation burner comprises a burner for oxidizing ammonia and a burner basket.

A dual pressure plant for the production of nitric acid, comprising: an air compressor; a converter, operating at a low pressure (LP), operable to be fed with a stream of an ammonia/pressurized air mixture to produce an LP gaseous NOx gas/steam mixture, comprising water, NO, NO.sub.2 and N.sub.2O.sub.4; a NOx gas compressor; an absorber unit (6); and a bleacher unit;
wherein the plant comprises means for directing the NOx-loaded stripping gas to the downstream side of the NOx gas compressor;
the plant being characterized in that it further comprises a high-pressure (HP) water electrolyser, in fluid communication with the bleacher unit.

The disclosure pertains to a nitric acid production process and plant. The process involves supplying an oxygen gas stream and ammonia feedstock to the burner section. In embodiments, a part of the tail gas stream (4) is heated in a tail gas heating section (7) and supplied to the burner section (1).

Disclosed is an apparatus for conversion of ammonia into oxides of nitrogen which may comprise an adiabatic burner (108), a set of platinum/rhodium alloy catalytic gauzes (102A), (102B), and (102C), a waste heat recovery boiler (WHRB) (110), an absorption tower (302A), (302B), (302C), (302D) and (302E), a NaOH tank (306) and a surge tank (304). Further, the adiabatic burner may be configured to carry out catalytic oxidation of air and ammonia, using catalytic gauzes (102A), (102B), and (102C) of platinum/rhodium alloy. Further, the mixture of air and ammonia may be selectively oxidized to oxides of nitrogen, which may be absorbed in an alkali medium in the absorption tower (302A), (302B), (302C), (302D) and (302E), to yield sodium nitrites and nitrates.

The present disclosure describes systems and methods for controlling the electrical generation of nitric oxide. In some aspects, a system for generating nitric oxide comprises a plasma chamber housing two or more electrodes in communication with a resonant high voltage circuit configured to send a signal to the plasma chamber for generating nitric oxide in a product gas from a flow of a reactant gas, and a controller configured to generate a pulse width modulation signal having multiple harmonic frequencies to excite the resonant high voltage circuit. The controller is configured to adjust the duty cycle of the pulse width modulation signal, the controller selecting the duty cycle based on a target voltage before plasma formation and a target current after plasma formation in the plasma chamber.

The disclosure pertains to a nitric acid production process and plant. The process involves supplying an oxygen gas stream and ammonia feedstock to the burner section. In embodiments, a part of the tail gas stream (4) is heated in a tail gas heating section (7) and supplied to the burner section (1).

A reactor may have a catalyst bed for the catalytic treatment of a gas stream, with the catalyst bed extending substantially over a cross section of the reactor. Gas to be treated may axially fly through the catalyst bed. A carrier structure for the catalyst bed that is at least partly floatingly mounted in the reactor may include a sieve element and, radially outwardly, carrier elements fixedly joined to the reactor wall below the sieve element. The sieve element provides a resting surface for the catalyst bed. The sieve element terminates, radially outwardly, at a distance from the reactor wall. The carrier structure also includes support elements for the sieve element that are floatingly mounted in the reactor. An improved floating mounting is thus provided where not only the sieve element itself but also further parts of the carrier structure are mounted to prevent stresses due to thermal expansion.

A system suitable for oxidizing ammonia with oxygen in the presence of catalysts is described. The system includes a reactor equipped with at least one supply line for a reactant gas mixture and at least one discharge line for a process gas; a catalyst comprising at least one transition metal oxide that is not an oxide of a platinum metal; and a device for adjusting a molar ratio of oxygen to ammonia of less than or equal to 1.75 mol/mol in the reactant gas mixture by mixing an oxygen-containing gas stream having an O.sub.2 content of <20% by volume with a chosen amount of ammonia. The oxygen-containing gas stream is produced by a device for: diluting an air stream with a gas stream comprising less than 20% by volume oxygen; or depleting oxygen from an oxygen-containing gas mixture, preferably from air; or by a combination thereof.

A system suitable for oxidizing ammonia with oxygen in the presence of catalysts is described. The system includes a reactor equipped with at least one supply line for a reactant gas mixture and at least one discharge line for a process gas; a catalyst comprising at least one transition metal oxide that is not an oxide of a platinum metal; and a device for adjusting a molar ratio of oxygen to ammonia of less than or equal to 1.75 mol/mol in the reactant gas mixture by mixing an oxygen-containing gas stream having an O.sub.2 content of <20% by volume with a chosen amount of ammonia. The oxygen-containing gas stream is produced by a device for: diluting an air stream with a gas stream comprising less than 20% by volume oxygen; or depleting oxygen from an oxygen-containing gas mixture, preferably from air; or by a combination thereof.