KR-20260065362-A - GREEN AMMONIA PRODUCTION SYSTEM

KR20260065362AKR 20260065362 AKR20260065362 AKR 20260065362AKR-20260065362-A

Abstract

The present invention relates to a green ammonia production system, characterized by comprising: a renewable energy facility unit that produces electricity in a manner that does not emit greenhouse gases; an ammonia production unit that produces ammonia using electricity supplied by the renewable energy facility unit; an energy storage facility unit that stores a portion of the electricity produced by the renewable energy facility unit, including a battery-based electrical storage device and an air liquefaction-type energy storage device, and supplies the stored electricity to the ammonia production unit; and a control unit that controls the operation of one or more of the renewable energy facility unit, the ammonia production unit, and the energy storage facility unit to compensate for the unstable power supply of the renewable energy facility unit and improve the power efficiency of the ammonia production unit.

Inventors

박종민
임태영

Assignees

한국전력기술 주식회사

Dates

Publication Date: 20260508
Application Date: 20241101

Claims (17)

Renewable energy facility unit that produces electricity in a way that does not emit greenhouse gases; An ammonia production unit that produces ammonia using electricity supplied by the above-mentioned renewable energy facility unit; An energy storage unit that stores a portion of the electricity produced by the renewable energy unit, including a battery-based electric storage device and an air liquefaction type energy storage device, and supplies the stored electricity to the ammonia production unit; and A green ammonia production system comprising a control unit that controls the operation of one or more of the above-mentioned renewable energy facility unit, the above-mentioned ammonia production unit, and the above-mentioned energy storage facility unit to supplement the unstable power supply of the above-mentioned renewable energy facility unit and improve the power efficiency of the above-mentioned ammonia production unit.
In paragraph 1, The above control unit is, The above battery-based electric storage device controls the output variability of the above renewable energy facility and adjusts the frequency, The above-described air liquefaction type energy storage device stores surplus electricity produced by the above-described renewable energy facility and controls the supply of the stored electricity to the above-described ammonia production unit, a green ammonia production system.
In paragraph 2, The above control unit is, A green ammonia production system that automatically controls charging and discharging so that the frequency of the above-mentioned battery-based electrical storage device is within the allowable error range of a standard frequency.
In paragraph 2, The above control unit is, A green ammonia production system that schedules the operation and load rate of the air liquefaction type energy storage device based on the power production amount of the renewable energy facility unit predicted based on weather information provided from the outside and the power demand amount required by the ammonia production unit, and controls the air liquefaction type energy storage device based on the generated schedule.
In paragraph 1, The above ammonia production unit, A hydrogen production facility that produces hydrogen by water electrolysis using electricity supplied by the above-mentioned renewable energy facility; Nitrogen production facility that produces nitrogen by separating nitrogen from the air in the atmosphere; An ammonia synthesis facility that synthesizes ammonia by synthesizing hydrogen provided by the hydrogen production facility and nitrogen provided by the nitrogen production facility; and A green ammonia production system comprising an ammonia liquefaction facility that liquefies gaseous ammonia provided by the ammonia synthesis facility.
In paragraph 5, The above-mentioned air liquefaction type energy storage device is, A liquefaction process unit comprising an air compressor and an air cooler, which compresses and cools air using surplus electricity produced by the renewable energy facility unit to liquefy it; A storage unit for storing air liquefied through the above liquefaction process unit; and A green ammonia production system comprising an air heater and an air turbine, and a power generation process unit that produces electricity by heating and vaporizing liquefied air provided by the storage unit.
In paragraph 5, The above ammonia synthesis facility is, A green ammonia production system that transfers the reaction heat generated during the ammonia synthesis process to an energy storage device of the air liquefaction method.
In paragraph 5, The above energy storage facility unit is, A green ammonia production system further comprising a heat storage unit that recovers and stores reaction heat generated during the above ammonia synthesis process and transfers the stored heat to an energy storage device of the above air liquefaction method.
In paragraph 6, The above ammonia synthesis facility is, A green ammonia production system that transfers the reaction heat generated during the ammonia synthesis process to the air heater to raise the inlet temperature of an air turbine located downstream of the air heater.
In paragraph 5, The above-mentioned air liquefaction type energy storage device is, A green ammonia production system that recovers cold energy emitted during a power generation process using liquefied air and transfers it to the ammonia liquefaction facility.
In paragraph 5, The above-mentioned air liquefaction type energy storage device is, A green ammonia production system that supplies low-temperature air discharged during a power generation process using liquefied air to the nitrogen production facility.
In paragraph 5, The above energy storage facility unit is, The cold energy discharged from the above air liquefaction type energy storage device is recovered and transferred to the above ammonia liquefaction facility, and A green ammonia production system further comprising a cold storage tank that supplies air discharged from the above-mentioned air liquefaction energy storage device to the above-mentioned nitrogen production facility.
In paragraph 6, The above-mentioned air liquefaction type energy storage device is, A green ammonia production system that recovers cold energy from low-temperature air passing through the above air turbine and transfers it to the above ammonia liquefaction facility.
In paragraph 6, The above-mentioned air liquefaction type energy storage device is, A green ammonia production system that supplies low-temperature air passed through the above air turbine to the above nitrogen production facility.
In paragraph 6, The above-mentioned air liquefaction type energy storage device is, A green ammonia production system that receives cryogenic nitrogen produced from the above nitrogen production facility and uses the above liquefaction process unit to liquefy air.
In paragraph 6, The above-mentioned air liquefaction type energy storage device is, A green ammonia production system that receives cryogenic nitrogen produced from the above nitrogen production facility and uses it for power generation in the above power generation process unit.
In paragraph 6, The above control unit is, When the power supply from the above-mentioned renewable energy facility is sufficient, A portion of the cryogenic nitrogen produced in the above nitrogen production facility is supplied to the above air liquefaction type energy storage device and used for cooling the air, and In the event that the power supply from the above-mentioned renewable energy facility is insufficient, A green ammonia production system that produces and supplies electricity using nitrogen stored in the above-mentioned air liquefaction energy storage device, and controls the discharged nitrogen to be supplied to the above-mentioned ammonia production facility.

Description

Green Ammonia Production System The present invention relates to a system for producing green ammonia, and more specifically, to a technology for optimizing the energy of a green ammonia production system. Ammonia ( NH₃ ) is a compound of nitrogen ( N₂ ) and hydrogen ( H₂ ) and has value as a means of responding to the climate crisis because it does not emit carbon dioxide, a greenhouse gas, during combustion. In particular, as the global economic structure transitions to a hydrogen economy and carbon neutrality, ammonia is gaining attention as an energy carrier that can resolve the regional unevenness and temporal variability of renewable energy, and as a carbon-neutral fuel that can be utilized in sectors such as power generation and transportation. To introduce clean hydrogen domestically, storage and transportation issues must first be resolved. Ammonia is considered a realistic alternative in terms of technological maturity and infrastructure utilization. While the appropriate hydrogen storage technology (high-pressure compression, liquefaction, liquid organic hydrogen carriers, ammonia, etc.) varies depending on the distance and volume of transport, ammonia is commonly used for long-distance, large-volume transportation, such as overseas imports. The reason ammonia can be utilized as a medium for the storage and transport of hydrogen is that it is more liquefied than hydrogen (liquefaction temperature at atmospheric pressure: hydrogen -253℃, ammonia -33℃) and can store 1.5 times more hydrogen than liquefied hydrogen, making it suitable as a hydrogen carrier. Additionally, because it has no carbon in its chemical structure, there is less concern about environmental pollution during combustion, so it can be used directly as a fuel for power generation, and hydrogen can also be extracted by decomposing ammonia. Ammonia is produced by combining nitrogen from the air with separately extracted hydrogen, and is classified into gray, blue, and green ammonia depending on the type of hydrogen combined. Furthermore, blue and green ammonia, which do not emit greenhouse gases throughout the entire process from production to utilization, are classified as clean ammonia. Here, ammonia produced by synthesizing nitrogen from the air after generating hydrogen through water electrolysis using renewable energy is referred to as green ammonia, and this green ammonia must be directly utilized to achieve carbon neutrality. The general components of the green ammonia production process are as shown in FIG. 1 and consist of a renewable energy facility (10) that produces electricity, a hydrogen production facility (21) that produces hydrogen by electrolyzing water using renewable energy, a nitrogen production facility (22) that produces nitrogen by separating nitrogen and oxygen from air in the atmosphere, an ammonia production facility (24) that produces ammonia by synthesizing hydrogen and nitrogen, and an ammonia liquefaction facility (25) that liquefies ammonia for transporting ammonia. The renewable energy facility (10) consists of solar photovoltaic (PV) and wind turbine (WT), and uses electricity produced through renewable energy to produce hydrogen using an electrolysis system (21) (EL). The nitrogen production facility (22) produces nitrogen by applying an air separation unit (ASU) and produces ammonia through the synthesis of hydrogen and nitrogen. Ammonia is produced in large quantities through the synthesis of hydrogen and nitrogen, mainly via the Haber-Bosch process, and finally, the ammonia is transported to a place of demand in a liquid state via a liquefaction facility (25). A stable power supply is critical for this green ammonia production process. In particular, since the ammonia production process is not suitable for responding to load fluctuations in renewable energy, a stable power supply must be continuously provided to the ammonia production and liquefaction processes, along with a fixed supply of hydrogen and nitrogen, to produce ammonia consistently without load variations. To this end, as shown in FIG. 1, to ensure a stable power supply, the renewable energy facility (10) is connected to the grid (11) or an electric storage device (12) (BESS, Battery Energy Storage System) is provided to compensate for the variability of the renewable energy facility (10) and to maintain the stability and balancing of the power supply, and a hydrogen storage facility (23) is provided to stably supply hydrogen produced through water electrolysis. However, when connected to the power grid (11), there is a technical limitation in that it is difficult to configure a perfect green ammonia production process because it relies more on external power supply rather than using 100% renewable energy sources, and there is a problem in that it is difficult to secure economic viability because the cost of building the facility increases rapidly when a large-capacity energy buffer is provided. In particular, in order to compensate