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KR-20260066731-A - A process for producing hydrogen and nitrogen products from an ammonia feed stream

KR20260066731AKR 20260066731 AKR20260066731 AKR 20260066731AKR-20260066731-A

Abstract

The present invention relates to a process (100) for producing hydrogen products and nitrogen products from an ammonia feed stream, In a reactor, the step of performing an endothermic cracking reaction of an ammonia feed stream (101) to produce a decomposition gas containing hydrogen and nitrogen, In the main separation unit, the main separation (102) of the decomposition gas stream is performed to produce a main separation unit tail gas comprising - a hydrogen product, - nitrogen and the remainder of hydrogen, In a secondary separation unit, the secondary separation (104) of the main separation unit tail gas is performed to produce the secondary separation unit tail gas and the nitrogen-depleted fuel stream as nitrogen products, The present invention relates to a process comprising the step of routing the above fuel stream to a furnace (115) to provide heat to an endothermic decomposition reaction.

Inventors

  • 바우어, 앙드레
  • 울버, 디터
  • 페지흐, 도미니크
  • 슈미트, 소피아
  • 비카리, 로렌초

Assignees

  • 레르 리키드 쏘시에떼 아노님 뿌르 레드 에렉스뿔라따시옹 데 프로세데 조르즈 클로드

Dates

Publication Date
20260512
Application Date
20240712
Priority Date
20230922

Claims (15)

  1. A process (100) for producing hydrogen products and nitrogen products from an ammonia feed stream, Step (101) of performing an endothermic cracking reaction of an ammonia feed stream in a reactor to produce a decomposition gas containing hydrogen and nitrogen, In the main separation unit, the main separation (102) of the decomposition gas stream is performed, - Hydrogen products, - A step of generating a main separation unit tail gas containing nitrogen and the remainder of hydrogen, In a secondary separation unit, the secondary separation (110) of the main separation unit tail gas is performed to produce the secondary separation unit tail gas and the nitrogen-depleted fuel stream as nitrogen products, A process comprising the step of routing the above fuel stream to fired equipment (115) to provide heat input to the process.
  2. In claim 1, the main separation step (102) comprises the step of removing unconverted ammonia from the decomposition gas stream (103) in an ammonia recovery unit to produce an unconverted ammonia stream and an ammonia-depleted decomposition gas, the process (100).
  3. In paragraph 2, the main separation step (102) includes a first nitrogen separation step (104), the first nitrogen separation step (104) includes separating an ammonia-depleted decomposition gas to produce a nitrogen-rich residue stream and a nitrogen-depleted permeate stream, the process (100).
  4. In claim 1, the main separation step (102) comprises a first nitrogen separation step (104), wherein the first nitrogen separation step (104) comprises separating a decomposition gas stream to produce a nitrogen-depleted permeate stream and a nitrogen-rich residue stream comprising nitrogen and the removed ammonia.
  5. In paragraph 3 or 4, the main separation step (102) includes a purification step (105), the purification step (105) includes purifying a nitrogen-depleted permeate stream in a purification unit to produce a hydrogen product and a main separation unit tail gas, the process (100).
  6. In paragraph 2, the main separation step (102) includes a purification step (105), and the purification step (105) includes purifying the ammonia depletion decomposition gas from the ammonia recovery unit in a purification unit to produce a hydrogen product and a main separation unit tail gas, the process (100).
  7. A process (100) wherein, in any one of paragraphs 3 to 5, the main separation step (102) includes an extraction step (108) that extracts a portion of the nitrogen-depleted permeate stream upstream of the purification step (105) to produce an extracted nitrogen-depleted stream.
  8. A process (100) wherein, in any one of paragraphs 2 to 7, the purification step (105) comprises a main compression step (106), and the main compression step (106) comprises compressing at least a portion of a nitrogen-depleted permeate stream or an ammonia-depleted decomposition gas to produce a compressed nitrogen-depleted permeate stream.
  9. In the eighth, the purification step (105) comprises separating the compressed nitrogen-depleted permeate stream into a hydrogen product and a main separation unit tail gas by pressure swing adsorption in a pressure swing adsorption unit (PSA unit) (107), the process (100).
  10. In any one of claims 1 to 9, the secondary separation step (110) comprises compressing the main separation unit tail gas (111) to produce the compressed main separation unit tail gas, the process (100).
  11. A process (100) comprising a control step (120) performed by a control unit comprising controlling the lower heating value (LHV) of a fuel gas stream in any one of claims 1 to 10.
  12. In paragraph 11, the control step (120) is - Step (130) of reducing the amount of extracted nitrogen depletion stream provided to the ignition equipment when the control value is higher than a predetermined control threshold, - and/or when the control value is lower than a predetermined control threshold, the process (100) includes the step (131) of increasing the amount of extracted nitrogen depletion stream provided to the ignition equipment.
  13. A process (100) according to any one of claims 1 to 12, wherein routing the fuel stream to an ignition device (115) comprises routing the fuel stream to a furnace (115) to provide heat to an endothermic decomposition reaction.
  14. As a device (1) for producing hydrogen products and nitrogen products from an ammonia feed stream, - A reactor (2) for performing an endothermic decomposition reaction of an ammonia feed stream to produce decomposition gas containing hydrogen and nitrogen, - Ignition device (3) configured to generate heat, - A main separation unit (4) configured to perform main separation of the decomposition gas stream to produce a main separation unit tail gas containing hydrogen product, nitrogen, and the remainder of hydrogen, - A secondary separation unit (5) configured to perform secondary separation that separates the tail gas of the main separation unit into nitrogen product and nitrogen-depleted fuel streams, - A device comprising a fuel line (7) configured to connect a secondary separation unit to an ignition device and route a fuel stream to the ignition device.
  15. In paragraph 14, the ignition equipment comprises a furnace configured to be thermally connected to the reactor (2) to provide heat for an endothermic decomposition reaction, the apparatus (1).

Description

A process for producing hydrogen and nitrogen products from an ammonia feed stream The field of the present invention is the field of a process for producing hydrogen products and nitrogen products by an endothermic cracking reaction of an ammonia feedstock stream. Furthermore, the present invention relates to an apparatus for producing hydrogen products and nitrogen products by an endothermic cracking reaction of an ammonia feedstock stream. Furthermore, the present invention relates to the use of such an apparatus for ammonia decomposition. The production of hydrogen products by the endothermic decomposition reaction of ammonia may include a separation step of separating the decomposition gas from the endothermic reaction into hydrogen products and separated tail gas. Subsequently, these tail gases may be used as fuel to be burned to provide heat to the endothermic reaction. However, tail gas still contains nitrogen and a portion of ammonia that was not decomposed during the ammonia decomposition reaction. If this tail gas is used directly as fuel, nitrogen oxides (NOx) are generated in the combustion exhaust. If the amount of nitrogen (N2), an inert gas, in the fuel stream is high, the lower heating value and flame stability of the fuel also decrease, and fuel consumption and steam export increase when cooling the combustion exhaust gas. The tail gas can also be separated into nitrogen-rich residues and nitrogen-depleting hydrogen products. Subsequently, nitrogen-rich residue can be discharged as fuel, but has the aforementioned disadvantages. Alternatively, nitrogen-rich residue can be exhausted into the atmosphere. Subsequently, nitrogen-depleted hydrogen products can be mixed with hydrogen products. The objective of the present invention is to overcome these problems and provide a process in which steam output is reduced, the generation of nitrogen oxides is reduced, and flame stability is improved. For this purpose, the present invention proposes a process for producing a hydrogen product and a nitrogen product from an ammonia feed stream, comprising the following steps: A step of performing an endothermic decomposition reaction of an ammonia feed stream in a reactor to produce decomposition gases containing hydrogen and nitrogen, In the main separation unit, the main separation of the decomposition gas stream is performed, hydrogen products, Step of generating a main separation unit tail gas containing nitrogen and the remainder of hydrogen, A step of performing secondary separation of the main separation unit tail gas in a secondary separation unit to produce secondary separation unit tail gas as a nitrogen product and a nitrogen-depleted fuel stream, A step of routing the above fuel stream to fired equipment to provide heat input to the process. The present invention may include at least one of the following features independently or in combination: Routing the fuel stream to an ignition device includes routing the fuel stream to a furnace to provide heat for an endothermic decomposition reaction. Routing the fuel stream to an ignition device may include routing the fuel stream to other devices, e.g., an ammonia feed preheater for preheating an ammonia feed stream, a gas turbine, and/or a water boiler for generating steam. The process includes the step of providing an ammonia feed stream to a reactor. The process includes the step of burning a fuel stream in the furnace to provide heat to an endothermic decomposition reaction. The decomposition gas stream contains the unreconverted portion of ammonia that was not reacted during the decomposition reaction. The main separation includes the step of removing unconverted ammonia from the decomposition gas stream in an ammonia recovery unit to produce an unconverted ammonia stream and an ammonia-depleted decomposition gas. For example, the step of removing unconverted ammonia from the decomposition gas stream may be a washing process performed in a washing column. The process includes the step of supplying the above unconverted ammonia stream to the reactor as an additional feed stream. The main separation step includes a first nitrogen separation step. The first nitrogen separation step is a step that separates ammonia-depleted decomposition gas to produce a nitrogen-rich residue stream and a nitrogen-depleted permeate stream. The main separation step includes a step of drying the unconverted ammonia stream upstream of the first nitrogen separation step. The first nitrogen separation step is performed in the first nitrogen separation unit. For example, the first nitrogen separation step is performed by a first membrane separator. The nitrogen-rich residue stream is under high pressure, for example, 15 barg to 45 barg, more preferably 20 barg to 30 barg. The nitrogen-depleted permeate stream is at a low pressure, for example, 1 barg to 10 barg, more preferably 1 barg to 5 barg. The main separation step includes a purification step. The purification step