GAS PRODUCTION PLANT

Abstract

A gas production plant includes an electrolysis arrangement for the production of gaseous hydrogen; an air separation arrangement for the production of gaseous nitrogen; a gas mixer configured to mix the gaseous hydrogen and the gaseous nitrogen in a predetermined mixing ratio; and an injector for injecting the resulting gaseous mixture into an export pipeline. A method of providing gaseous reactants for an ammonia synthesis plant is also provided.

Claims

1. A gas production plant comprising an electrolysis arrangement for the production of gaseous hydrogen; an air separation arrangement for the production of gaseous nitrogen; a gas mixer configured to mix the gaseous hydrogen and the gaseous nitrogen in a predetermined mixing ratio; and an injector for injecting the resulting gaseous mixture into an export pipeline.

2. The gas production plant according to claim 1, wherein the gas mixer is configured to mix the gaseous hydrogen and the gaseous nitrogen in a mixing ratio of three parts gaseous hydrogen to one-part gaseous nitrogen.

3. The gas production plant according to claim 1, wherein the electrolysis arrangement is configured to perform water electrolysis.

4. The gas production plant according to claim 1, wherein the air separation arrangement is configured as any of: a pressure swing adsorption arrangement, a cryogenic distillation arrangement, a pressurized reverse osmosis membrane arrangement.

5. The gas production plant according to claim 1, wherein the electrolysis arrangement is powered by a wind energy plant.

6. The gas production plant according to claim 1, wherein the air separation arrangement is powered by a wind energy plant.

7. The gas production plant according to claim 5, wherein a wind energy plant comprises one or more offshore wind turbines.

8. An ammonia production arrangement comprising the gas production plant according to claim 1 for supplying a gaseous mixture of hydrogen and nitrogen; an ammonia synthesis plant configured to synthesize ammonia from the gaseous mixture; and an export pipeline connecting the gas production plant and the ammonia synthesis plant.

9. The ammonia production arrangement according to claim 8, wherein the export pipeline is made from a thermoplastic material.

10. A method of providing gaseous reactants for an ammonia synthesis plant, which method comprises the steps of S1.1) performing electrolysis to obtain gaseous hydrogen; S1.2) performing air separation to obtain gaseous nitrogen; S2) mixing the gaseous hydrogen and the gaseous nitrogen in a predetermined mixing ratio; S3) injecting the resulting gaseous mixture into an export pipeline; and S4) transporting the gaseous mixture in the export pipeline to the ammonia synthesis plant.

11. The method according to claim 10, wherein the mixing step is preceded by a gas purification step.

12. The method according to claim 10, comprising a step of compressing the gaseous mixture prior to injection into the export pipeline.

Description

BRIEF DESCRIPTION

[0021] Some of the embodiments will be described in detail, with reference to the following figures, wherein like designations denote like members, wherein:

[0022] FIG. 1 shows an embodiment of the inventive ammonia production arrangement; and FIG. 2 is a flowchart illustrating the inventive method.

DETAILED DESCRIPTION

[0023] FIG. 1 is a simplified schematic showing a possible realization of the inventive ammonia production arrangement 1 using an embodiment of the inventive precursor gas delivery plant. The entire configuration may be divided roughly into three stages (as indicated here by the dotted lines) namely gas delivery 10, ammonia production 11, and a pipeline link 12.

[0024] In this exemplary embodiment, an offshore wind farm 2 is used to power water electrolysis plants 10H and air separation plants 10N. Here, various wind turbines 20 provide power to water electrolysis modules 10H to obtain gaseous hydrogen H.sub.2. Other wind turbines 20 provide power to air separation modules 10N to obtain gaseous nitrogen N.sub.2.

[0025] The diagram shows one electrolysis module 10H and one air separation module 10N for clarity, but it shall be understood that each wind turbine 20 could drive an electrolysis module 10H and/or an air separation module 10N. Equally, any one of these modules 10H, 10N can be powered by more than one wind turbine 20.

[0026] An electrolysis module 10H and/or air separation module 10N in combination with its source of power is referred to as a gas production plant 10. Of course, an electrolysis module 10H or air separation module 10N could be powered by any suitable source of electricity.

[0027] For example, wind energy may be used to drive water electrolysis to produce H.sub.2, while photovoltaic modules can be used to drive air separation to produce N.sub.2. In an exemplary realisation, a photovoltaic unit can be installed directly on (or in the immediate vicinity of) a wind turbine 20, so that each wind turbine installation comprises a water electrolysis arrangement 10H powered by the wind turbine 20, and an air separation unit 10N powered by the photovoltaic unit. In this way, hydrogen and nitrogen production are close together, allowing the gases to be mixed essentially directly in the desired ratio for the export pipeline 12, without having to transport the gases separately over any significant distance.

[0028] The gaseous hydrogen H.sub.2 and the gaseous nitrogen N.sub.2 are combined by a gas mixer 101 in a predetermined stoichiometric ratio, at a ratio of 3:1 (three parts gaseous hydrogen H.sub.2 to one-part gaseous nitrogen N.sub.2). Prior to mixing, each gas can be purified by a suitable purification arrangement, as will be known to the skilled person.

[0029] The stoichiometric gaseous mixture M is compressed to a pressure of up to 10 MPa using a suitable compressor 102, and an injection means 103 subsequently injects the pressurized mixture M into an export pipeline 12.

[0030] The pressurized mixture M is transported to an ammonia synthesis plant 11 (indicated here simply as a process stage), which may be located at a remote location, for example on the mainland or near the shore. As will be known to the skilled person, the ammonia synthesis plant 11 can directly apply the Haber-Bosch process to synthesize ammonia from the pressurized 3:1 mixture of H.sub.2 and N.sub.2.

[0031] FIG. 2 is an exemplary flowchart to illustrate steps of the inventive method of providing gaseous reactants H.sub.2, N.sub.2 for an ammonia synthesis plant. The method comprises an initial step S1.1 of performing electrolysis to obtain gaseous hydrogen H.sub.2, and an initial step S1.2 of performing air separation to obtain gaseous nitrogen N.sub.2. The gaseous hydrogen is purified in step S1.11, and the gaseous nitrogen is purified in step S1.21. The purified reactants are then mixed in a subsequent step S2 according to a predetermined mixing ratio, for example a stoichiometric ratio suitable for a subsequent Haber-Bosch process as described above. The gas mixture is then pressurized to a suitable pressure in step S2.1. In step S3, the pressurized gas mixture M is then injected into an export pipeline, and transported in step S4 to the ammonia synthesis plant (or to a storage facility).

[0032] Although the present invention has been disclosed in the form of preferred embodiments and variations thereon, it will be understood that numerous additional modifications and variations could be made thereto without departing from the scope of the invention.

[0033] For the sake of clarity, it is to be understood that the use of "a" or "an" throughout this application does not exclude a plurality, and "comprising" does not exclude other steps or elements. The mention of a "unit" or a "module" does not preclude the use of more than one unit or module.