Process and plant for the synthesis of ammonia from a hydrocarbon feedstock, comprising: primary reforming with steam and air-fired secondary reforming wherein primary reforming is performed at a temperature and pressure of at least 790 C. and 50 bar, and secondary reforming is carried out substantially in absence of excess air, the so obtained make-up synthesis gas having a H.sub.2 to N.sub.2 molar ratio in the range 2.5 to 3.

A dual pressure process for the synthesis of ammonia from a make-up gas, wherein the make-up gas is reacted in two steps in series, the second step operating at a greater pressure than the first step, and wherein a portion of the effluent of the first step is recycled back to the first step, said portion containing unreacted make-up gas.

A process and apparatus for reducing wastewater generated during production of ammonia that can have different levels of production (e.g. ammonia production can vary from 10% to 100% production capacity, etc.) can be configured to minimize or eliminate wastewater from ammonia production. Embodiments can be adapted so that wastewater is stored in a vessel and providable to a scrubber used for processing an ammonia vapor containing stream so that ammonia within that stream can be recovered and mixed with other liquid ammonia product for subsequent storage or use. Embodiments can be implemented so the scrubber stream that may utilize a liquid to perform the scrubbing is recyclable in a way that minimizes or even eliminates formation of a wastewater stream, which can significantly improve process efficiency and provide improved environmental operation as compared to conventional approaches.

Process for synthesis of ammonia wherein the synthesis of ammonia is performed in a high-pressure synthesis loop which is partially fed with green hydrogen produced from a renewable energy source and hydrogen recovered from a purge stream of the loop is stored in a hydrogen storage to compensate for temporary lack of the green hydrogen when the renewable energy source is not fully available.

A method for separating inert gases, from ammonia gas in an ammonia production plant, comprising the steps of: a) adjusting the temperature of a first gas comprising ammonia gas and the inert gases to a temperature equal to or lower than ?20? C., thereby producing liquid ammonia and an inert gas depleted in ammonia; b) ejecting the inert gas stream produced in step a) to an inert gas station, using a gas stream from the ammonia production plant as the motive gas in a gas ejector, thereby ejecting a gas stream at the outlet of the ejector; and c) using the gas stream from the inert gas station, after its ejection in step b), as the component of a fuel.

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.

An ammonia plant is disclosed, where ammonia purge gas (20), is sent to a cryogenic recovery unit, said recovery unit comprising means of cooling (102, 202, 302, 402, 502) and a high-pressure phase separator (103, 203, 303, 403, 503) operating at loop pressure; inside said unit the purge gas (20) is cooled to a cryogenic temperature, and a partial liquefaction of methane and argon is achieved; the high-pressure phase separator separates the cooled stream into a gaseous stream and a bottom liquid; the gaseous stream is reheated in a passage of a heat exchanger; the unit is then capable to export a gaseous stream (123, 223, 323, 423, 523) containing nitrogen and hydrogen at loop pressure, that can be reintroduced at the suction side of the circulator (4) of the loop.

A system and method for producing ammonia at high conversion rates. The system having a fluidized bed reactor with a fluidized zone with catalyst particles. The fluidized bed reactor is preferably configured to receive a continuous flow of solid sorbent particles, nitrogen, and hydrogen, with the catalyst particles being at least ten times larger than the sorbent particles. The method allows for the nitrogen and hydrogen react on a surface of the catalyst in order to generate ammonia that is adsorbed by the sorbent particles. The method extracts the adsorbed ammonia from the sorbent particles with a sorbent regenerator to product a pure ammonia product.

A plant for producing an argon-rich stream from a mixture formed by a purge fluid from a plant for producing ammonia comprises at least two methane scrubbing columns upstream of a methane separation column and, downstream therefrom, a nitrogen/argon separation column.

Process and plant for the synthesis of ammonia from a hydrocarbon feedstock, comprising: primary reforming with steam and air-fired secondary reforming wherein primary reforming is performed at a temperature and pressure of at least 790 C. and 50 bar, and secondary reforming is carried out substantially in absence of excess air, the so obtained make-up synthesis gas having a H.sub.2 to N.sub.2 molar ratio in the range 2.5 to 3.