Energy delivery using AQUA-ammonia

Abstract

There is provided an energy delivery system using aqua-ammonia as a fuel source. The system comprises an aqua-ammonia distillation separator (11) configured to separate the aqua-ammonia into water and a gaseous distillation product comprising ammonia. The system further comprises an ammonia-air storage tank (16) configured to store the ammonia generated by the aqua-ammonia distillation separator (11); and an ammonia burner (12) configured to burn the ammonia to produce hot combustion products for use in heat and / or power generation. There is also provided a method of utilising aqua-ammonia as a power source.

Description

[0001] ENERGY DELIVERY USING AQUA-AMMONIA

[0002] Field of invention

[0003] This invention relates to carbon-free energy delivery systems using Aqua-ammonia - based fuels, targeting a range of energy applications to achieve net-zero CO2emissions. While applicable to residential / space heating, it also extends to power generation, industrial processes, and other sectors that currently rely on natural gas.

[0004] Background to the invention.

[0005] Global efforts to achieve net-zero emissions have made significant progress in sectors such as transportation and renewable energy. However, the first critical step toward reaching net-zero carbon emissions is to phase out natural gas completely. Simultaneously, it is beneficial to repurpose the extensive existing infrastructure of natural gas for fuels that align with sustainability goals.

[0006] Two key sectors that heavily rely on natural gas and significantly contribute to carbon emissions are space heating and power generation. In the UK, the residential heating sector accounts for approximately 30% of CO2emissions, while power generation remains a substantial source of greenhouse gas emissions. Currently, the energy mix for power generation includes renewable sources such as wind and solar, which contribute less than 30% of the electricity generation of the UK.

[0007] Hydrogen has been proposed as an alternative to natural gas; however, it presents several challenges. Hydrogen has one-third the energy density by volume compared to natural gas, leadingto increased energy loss duringstorage and transportation. Adapting existing natural gas pipelines for hydrogen could entail significant costs in the UK alone, with estimates indicating that over 85% of the current gas distribution network may need modifications or replacement to safely accommodate hydrogen. Additionally, hydrogen has a higher energy release upon ignition, with about 120 MJ / kg compared to natural gas at 50 MJ / kg, raising safety concerns regarding its explosive potential, especially in residential heating application.

[0008] Biogas, produced from organic waste through anaerobic digestion, is another alternative fuel option that can help reduce reliance on natural gas. It has the advantage of being renewable and can be upgraded to biomethane, making it compatible with existing natural gas infrastructure to some extent. However, biogas poses several challenges when considered as a large-scale replacement for natural gas. The production of biogas is limited by the availability of organic waste, which restricts its scalability compared to other fuel options. Additionally, biogas requires extensive purification to remove impurities like hydrogen sulphide and carbon dioxide to meet the quality standards of natural gas pipelines. Despite these challenges, biogas remains a viable alternative in localized applications but may face limitations as a primary fuel source for large-scale distribution. Ammonia, composed of nitrogen and hydrogen, has been recognized for its high energy density and relative ease of storage compared to hydrogen. While ammonia remains liquid at low pressures and ambient temperatures, making it more practical for certain applications, it is not suitable for replacing natural gas within the existing infrastructure, as it cannot be transported using current gas pipelines. Additionally, the use of pure ammonia as a fuel for space heating presents significant challenges, including toxicity, corrosiveness, and a pungent odour, which render it unsuitable for direct residential heating.

[0009] The present invention aims to at least ameliorate the above-mentioned issues with fuels and present alternatives to natural gas as a fuel source.

[0010] Summary of the Invention

[0011] According to a first aspect of the present invention, there is provided an energy delivery system using aqua-ammonia as a fuel source. The system comprises an aqua-ammonia distillation separator configured to separate the aqua-ammonia into water and a gaseous distillation product comprising ammonia. The system further comprises an ammonia-air storage tank configured to store the ammonia generated by the aqua-ammonia distillation separator. The system further comprises an ammonia burner configured to burn the ammonia to produce hot combustion products for use in heat and / or power generation.

[0012] Aqua-ammonia, a solution of ammonia in water, offers an innovative alternative to the issues discussed with other fuel sources. This carbon-free fuel mitigates some of the drawbacks associated with pure ammonia. It is less toxic, safer to handle, and can potentially leverage existing infrastructure with minimal modifications. When comparing fuel delivery via existing pipeline infrastructure, aqua-ammonia offers distinct advantages over natural gas. Unlike natural gas, which requires elevated pressures for efficient delivery, aqua-ammonia can be transported at near-ambient conditions, significantly simplifying pipeline operation and reducing the energy overhead associated with compression. At standard temperature and pressure, aqua-ammonia remains a liquid, inherently increasing volumetric energy transfer efficiency.

[0013] Strikingly, a low concentration of 6 wt% A-A matches the volumetric energy density of natural gas in current pipelines. This implies that, without any modifications to pipeline capacity, increasing the concentration of aqua-ammonia can multiply the energy delivered several-fold.

[0014] Aqua-ammonia’s high energy density and compatibility with advanced power generation technologies, such as gas turbines and fuel cells, position it as a viable option for sustainable and scalable power production. Furthermore, its use in hybrid systems combining combustion and fuel cell technologies could significantly enhance efficiency while minimizing greenhouse gas emissions. The presence of water in ammonia is generally regarded as an impurity, since during combustion water can hinder complete combustion and reduce fuel efficiency. However, the inventors surprisingly found that aqua-ammonia can provide safe, low-cost, and highly efficient medium for energy transmission, particularly when considering the full cycle of energy and heat generation (including, for example, production and transportation / supply of the fuel source).

[0015] This invention leverages aqua-ammonia as a clean, carbon-free fuel for heating and power generation, aiming to bridge the gap between the need for reliable energy and the urgency of reducing carbon emissions. The transmission network for this fuel is much cheaper than similar fuels due to its liquid state and water-like behavior.

[0016] The present invention positions aqua-ammonia as a highly adaptable and efficient energy carrier. By leveraging existing natural gas infrastructure, it enables a smooth, phased transition to carbon-free fuel with minimal new installations. Delivered at ambient conditions, it achieves superior volumetric energy density while simplifying deployment. Its dual functionality as an energy and water carrier further enhances sustainability, supporting applications such as desalination or closed-loop water management. This integrated approach addresses both energy and water challenges, offering a scalable, cost-effective, and environmentally responsible solution.

[0017] Burning ammonia generates hot combustion products, which may be used in combination with heat exchangers to provide heating in domestic and industrial settings. Alternatively, the ammonia burner may be used in a turbine, where the hot combustion products drive the turbine blades. Alternatively, the ammonia burner may form part of an internal combustion engine, wherein the combustion products drive the engine. There are multiple applications where the present invention of utilising aqua-ammonia as a fuel source, resulting in hot combustion products from burning ammonia produced from a distillation separator, could provide a viable alternative to present fuels, such as fuel cells.

[0018] In the context of space heating, upon arrival to the target space, aqua-ammonia enters the distillation separator and burner set-up, which may be referred to as an “aqua- ammonia heating boiler”. This is designed to replace traditional natural gas boilers. Within the aqua-ammonia heating boiler, aqua-ammonia is separated into water and ammonia using the distillation separator. Ammonia fuels a burner and the water may be recycled or repurposed for other uses as discussed within the present application, thereby providing a sustainable and efficient heating solution.

[0019] Additionally or alternatively, the aqua-ammonia fuel can be used to generate power. In this context, aqua-ammonia is directed to the power generation system, which first separates ammonia from water based on the same distillation separator set-up. The separated distillation products, comprising ammonia then fuels the ammonia-powered power generation system, such as ammonia gas turbines, internal combustion engines, or ammonia-based fuel cells. The exhaust products from these applications can provide the required thermal energy for separating ammonia from water. This again improves the overall efficiency of the system: exhaust products are utilised in an energy-efficient manner.

[0020] The capability to simultaneously transfer energy and water makes the present invention particularly useful for applications such as water desalination. If non-potable water is utilized, the separation process can produce drinkable water by harnessingthe heat from the exhaust or combustion products, integrating water purification energy directly into the heating system or power generation used. If water is not needed, it can be safely discharged into existing sewer systems. In water-scarce regions, implementing a closed- loop water cycle with a drain or sewer system can optimize resource management effectively. This approach not only enhances energy efficiency but also supports sustainable water management, addressing both energy and water scarcity challenges in an integrated manner.

[0021] The ammonia burner may comprise an igniter and an air-ammonia blower configured to supply an air-ammonia mixture from the air-ammonia storage tank. The ammonia burner may comprise an additional air pump to provide additional airto the mixture in instances where this would aid combustion of the ammonia.

[0022] The aqua-ammonia distillation separator may comprise a distillation tank; a heat source disposed within the distillation tank configured to heat the aqua-ammonia; one or more porous plates disposed within the distillation tank to separate the distillation tank into tiers, each of the one or more porous plates configured to support liquid whilst allowing passage of gases such that gas may bubble through any liquid supported by each of the one or more porous plates. The distillation separator may further comprise a first inlet fluidly connected to the distillation tank and configured to provide aqua-ammonia into the distillation tank; a second inlet fluidly connected to the distillation tank, and configured to provide an airstream into the tank; a first outlet for outputting gaseous distillation products; and a second outletfor discharging distilled water. Thefirst inlet and first outlet may disposed above the one or more porous plates; and the second inlet and second outlet disposed below the one or more porous plates, such that the airstream from the second inlet creates a pressure differential and carries evaporated gases from the distillation tank up to the first outlet.

[0023] The one or more porous plates may comprise hydrophobic membrane, such as Polytetrafluoroethylene (PTFE), Polypropylene (PP), Polyvinylidene Fluoride (PVDF), etc. . These permit the passage of gases (such as water vapour, ammonia, air) whilst restricting the passage of liquid water.

[0024] Advantageously, the provision of these porous plates increases the time of contact of the liquid aqua-ammonia during the separation process, which leads to better performance of the separator.

[0025] The distillation separator operates on the basis that ammonia and water have different boiling temperatures. Ammonia is also less dense than water vapour and so will rise to the top of the distillation separator. This is encouraged by the injection of air into the distillation tank via the second inlet, which creates a pressure differential and encourages the movement of the evaporated gases up to the first outlet.

[0026] The distillation separator may comprise a third inlet, where an ammonia-air mixture is provided from the air-ammonia storage tank. This may act to improve the yield of the ammonia produced by the separator by providing multiple iterations of the distillation product through the separator. Further advantageously, this third inlet may contribute to the pressure differential produced by the injection of air by the second inlet.

[0027] The heat source may comprise an exhaust pipe passing through the distillation tank, the exhaust pipe configured to carry the hot combustion products from the ammonia burner such that the hot combustion products provide a heat source for the separation.

[0028] Advantageously, using the hot combustion products as a heat source for the separation improves the overall efficiency of the system. The hot combustion products are produced as part of the burning process, and there is a low energy cost to use this heat to raise the temperature of aqua ammonia.

[0029] The distillation separator tank may be annular, with the exhaust pipe passing through the central recess of the tank. Advantageously, this may provide a consistent heating across the tank. As an alternative configuration, the ammonia burner may be disposed in the recess. This provides a more compact arrangement.

[0030] Additionally, or alternatively, the heat source may comprise an electric heater disposed within the distillation tank.

[0031] This electric heater may be used in combination with the exhaust pipe as a heat source. The use of the electric heater may be used primarily for start-up (i.e. before any hot combustion products are produced) and to provide additional or replacement heating where necessary (i.e. during unstable conditions or restricted flow of the hot combustion products). Advantageously, having a secondary heat source can enable a continuous function of the separator rather than sole reliance on another aspect of the system.

[0032] The energy delivery system may further comprise a heat exchanger through which the hot combustion products flow in use, such that heat is transferred from the hot combustion products to a working fluid of a heating system.

[0033] The energy delivery system may further comprise a secondary heat exchanger through which water discharged from the second outlet flows in use, such that heat is transferred from the discharged water to a working fluid of a or the heating system.

[0034] The or each heat exchanger may be a brazed plate heat exchanger. Advantageously, provision of a secondary heat exchanger for the discharged water to transfer heat improves the efficiency of the system. Otherwise discarded water can instead contribute to raising the temperature of the working fluid of a heating system.

[0035] The energy de livery system may further comprise a condenser fluidly connected between the separator and the storage tank. The condenser may be configured to receive the gaseous distillation product and dehumidify the gaseous distillation product. In use, the condenser cools the gaseous distillation products. This causes moisture to condense from the gaseous distillation product because water has a lower boiling point than ammonia. Condensing the moisture out of the distillation products acts to dehumidify the gaseous distillation products. The present invention is designed for combusting aqua-ammonia with a high water content. The utilisation of the condenser can improve the combustion efficiency of the system by further dehumidifying the gaseous distillation products beyond the separation provided by the distillation separator.

[0036] The condenser may comprise an interior pipe through which the gaseous distillation product flows in use, and an aqua-ammonia well configured to receive aqua-ammonia in use and fluidly connected to the separator such that an outlet of the well comprises an aqua-ammonia inlet into the separator. The exterior surface of the interior pipe may interface with the well such that heat is transferred from the gaseous distillation product to the aqua-ammonia fuel in use.

[0037] The aforementioned aqua ammonia inlet may be the first inlet referred to when discussing the distillation separator previously.

[0038] The first pipe may sit at least partially within the well. The first pipe may extend beyond the well such that it is exposed to air, which acts to further cool the gaseous distillation products and condense moisture from the products.

[0039] Advantageously, using the aqua-ammonia fuel as a source of cooling the gaseous distillation products acts to pre-heat the aqua-ammonia prior to entering the separator.

[0040] The interior pipe may be coiled vertically, such that condensed moisture exits the interior pipe under the action of gravity. Advantageously, this returns the condensed moisture to the separator, where it may then be reheated and possibly discharged through the second outlet for use in heating the working fluid of the system. As discussed in the present application, providing a closed-loop system (or close to one) with respect to water can improve the environmental impact of the energy delivery system.

[0041] The energy delivery system may further comprise a recuperator heat exchanger through which, in use, aqua-ammonia fuel flows prior to distillation, and distilled water flows post-distillation, such that heat is transferred from the distilled water to the aqua- ammonia fuel.

[0042] Advantageously, this acts to pre-heat the aqua-ammonia fuel, improving the thermal efficiency of the system. This reduces the energy waste that could otherwise be associated with the system, where hot water was discharged without being used. As an illustrative example, in 1 kg of 13%wt aqua-ammonia, there is about 2.85MJ of heating potential from burning the ammonia. In the same 1 kg of 13%wt aqua-ammonia, there is 0.87kg of water. Heating that water up by 40 degrees C would require 0.146MJ. This equates to approximately 5% of the available 2.86MJ produced by burning that 1 kg of aqua-ammonia. Were the heated water to be discharged without further use (either in a recuperator as discussed or to transfer heat to the working fluid of a heating system), the energy delivery system would be approximately 5% less efficient.

[0043] The air-ammonia storage tank may comprise a tank body; a first storage inlet to receive the gaseous distillation products; a separation membrane configured to separate the tank body into upper and lower sections, wherein the membrane restricts the flow of ammonia from the upper to lower sections; a first outlet disposed above the separation membrane to receive outgoing ammonia to the burner; and a second outlet disposed below the separation membrane to receive outgoing air to the separator.

[0044] As discussed previously, the second outlet may be an additional inlet into the separator, supplying an air-ammonia mixture into the distillation separator. Advantageously, this increases the efficiency of system: less air is required to be pumped into the system to generate the desired flow of gases; and yield of ammonia is increased by cycling the products through the distillation separator until saturated.

[0045] Ammonia is less dense than air and so would naturally rise to the top of tank regardless of the separation membrane. However, the separation membrane reduces the exchange of gases near the outlet: ammonia and air are being received by the storage tank and so it is expected that movement of the gases would occur rather than a steady-state of settled positions. The separation membrane helps to “capture” the air at the base of the storage tank. The separation membrane may comprise mixed-matrix membranes (MMMs) with NH3-adsorbing fillers. Examples of such fillers may include zeolites.

[0046] The air-ammonia storage tank may comprise a flame suppressant. This flame suppressant may comprise a steel mesh. This acts to improve the safety of the system, and prevent or reduce the risk of rapid ignition of the ammonia stored in the tank even in the situation where a localised temperature rise occurred.

[0047] The energy delivery system may further comprise one or more sensors configured to determine one or more of: i. volume of aqua-ammonia within the separator; ii. temperature of the separator; iii. temperature of separated water; iv. pressure within the air-ammonia storage tank v. where present, temperature of any working fluid of a heating system.

[0048] The energy delivery system may further comprise a controller, the controller configured to regulate one or more of: i. the temperature of the separator; ii. flow of aqua-ammonia fuel into the separator iii. flow of air and / or air-ammonia into the ammonia burner; iv. flow of ammonia into the ammonia burner; v. flow of separated water into a heat exchanger; vi. flow rate of hot combustion products into a heat exchanger, turbine or other working system.

[0049] The controller may control the flow of one or more of the fluids discussed by controlling one or more valves. These valves may be simple on / off valves, or may be graduated.

[0050] The controller may be further configured to regulate the flow rate of the hot combustion products through the separator. This may comprise controlling a bypass valve, associated with a bypass pipe that circumvents the separator such that a portion of the hot combustion products do not pass through the separator. This allows for a method of controlling the temperature of the separator. For example, where a lower yield of ammonia is required, a lower temperature for the distillation separator may be satisfactory. Alternatively, higher energy transfer may be required at the heat exchanger through which the hot combustion products flow or a higher kinetic energy flow may be necessary for a turbine. Reducing the energy transfer from the hot combustion products to the separator would achieve this effect. By providing a controller and bypass means, the system is able to be flexible to suit the need at a specific time.

[0051] The energy de livery system may further comprise an aqua-ammonia production unit; and aqua-ammonia transmission means, comprising pipelines arranged to transport the aqua-ammonia produced in the aqua-ammonia production unit to the aqua-ammonia distillation separator.

[0052] The system may include the establishment of an aqua-ammonia production unit, where ammonia is mixed with water to create the fuel. Given the toxicity of ammonia, it is recommended that the production unit be located outside urban or densely populated areas to ensure safety. Pure ammonia will be produced or transported to this unit using established methods such as shipping, trucking, or piping.

[0053] At least some of the aqua-ammonia transmission means may utilise pre-existing natural gas infrastructure. The production unit could be strategically positioned near gas transmission pipelines and pressure regulation stations for optimal integration.

[0054] As discussed in the present application, aqua-ammonia, formed by dissolving gaseous ammonia in water, combines the benefits of ammonia with reduced toxicity and lower corrosiveness. Unlike pure ammonia, which is gaseous and occupies more volume under atmospheric conditions, aqua-ammonia remains liquid at atmospheric pressure, improving its efficiency for fuel transfer. Utilising existing natural gas infrastructure enables efficient repurposing in the event of a phased transition away from natural gas. The existing infrastructure is not only materially compatible with aqua-ammonia but also offers ample capacity for its energy delivery. As previously noted, even a modest 6 wt% concentration of aqua-ammonia provides a volumetric energy density equivalent to that of natural gas within current pipelines, while higher concentrations can deliver several- fold greater energy throughput. This adaptability significantly reduces the need for extensive new installations, building upon the current infrastructure allows for a gradual, region-by-region implementation strategy, ensuring a smooth transition.

[0055] Further advantageously, the supply of aqua-ammonia as a fuel source can operate near standard pressures and temperatures, facilitating straightforward and cost-effective access and deployment.

[0056] According to a second aspect of the present invention, there is provided a method of utilising aqua-ammonia as a power source. The method comprises the steps of: a. supplying aqua-ammonia to a distillation separator; b. separating the aqua-ammonia with the distillation separator to produce gaseous distillation products comprising ammonia; b. optionally storing the gaseous distillation products; c. burning the gaseous distillation products to produce hot combustion products; d. utilising the hot combustion products to transfer heat and / or power.

[0057] As discussed with respect to the first aspect, utilisation of the hot combustion products may include heat transfer for domestic or industrial heating, power generation in gas turbines or internal combustion engines or other applications such as fuel cells.

[0058] The method may further comprise the step of: bi. afterseparatingthe aqua-ammonia, dehumidifyingthe gaseous distillation products with a condenser.

[0059] This step may be performed before or after storage of the gaseous distillation products, but will be performed prior to burning the products. Moisture reduces the efficiency of the ammonia burner. In some applications, moisture reduction is less of a concern (e.g., where there is continuous energy consumption). However, there are others where the efficiency of the burner at any given time is paramount, and moisture is not desirable. These applications may include space heating, where there may be fluctuations in energy consumption and so the distillation products are stored for a longer period of time prior to burning.

[0060] The method may further comprise an initial step of dissolving ammonia in water to produce aqua-ammonia in an aqua-ammonia production unit.

[0061] Supplying aqua-ammonia may comprise utilisation of existing natural gas infrastructure.

[0062] Optional and preferred features associated with the first aspect of the present invention may similarly be applicable to the second aspect of the present invention. Similarly, advantages discussed with respect to the first aspect of the present invention (improved efficiency, reduced carbon footprint etc.) apply equally to the second aspect of the present invention.

[0063] Brief Description of the Drawings

[0064] Figure 1 illustrates the heating system using Aqua-Ammonia as a fuel;

[0065] Figure 2 illustrates the Aqua-Ammonia heating boiler with condenser (9);

[0066] Figure 3 illustrates the Aqua-Ammonia heating boiler without condenser (9);

[0067] Figure 4 depicts the condenser (9);

[0068] Figure 5 shows the ammonia separator (14);

[0069] Figure 6 illustrates the ammonia-air storage tank (16);

[0070] Figure 7illustrates a schematic layout of the aqua-ammonia production unit (1 ), fuel transmission pipelines (2), and the aqua-ammonia power plant system (44);

[0071] Figure 8 illustrates a schematic for the integration of the aqua-ammonia system with internal combustion engines (50) for power generation;

[0072] Figure 9 illustrates a schematic for the integration of the aqua-ammonia system with gas turbines (51 ) for power generation.

[0073] Figure 10 illustrates a schematic for the integration of the aqua-ammonia system with steam cycles (52) for power generation.

[0074] Figure 11 illustrates a schematic for the integration of the aqua-ammonia system with fuel cells (54), including ammonia cracker units (55) where necessary.

[0075] Figure 12 illustrates a schematic for the energy supply method for separation by an engine cooling system.

[0076] Figure 13 illustrates a schematic for a method of utilising aqua-ammonia as a power source.

[0077] Detailed Description

[0078] Figure 1 illustrates the layout of the aqua-ammonia production unit (1 ), fuel transmission pipelines (2), and the aqua-ammonia burner heating system (3).

[0079] The aqua-ammonia production unit (1 ) consists of three primary tanks: a water tank (4), an ammonia tank (5), valve or expander (6), evaporator (7) and a controlled mixing tank (8). Non-potable water, such as rainwater, may also be utilized in this process, further enhancing resource efficiency. The method of producing aqua-ammonia will be known to “a person skilled in the art”. The resulting liquid aqua-ammonia is injected into available natural gas transportation pipelines or new pipeline, at pressures between 1-4 bars, similar to water distribution systems, for delivery to space heating units or the power plants. Aqua-ammonia enters the aqua-ammonia burner heating system (3) through a pipeline. This system consists of two main components: the aqua-ammonia burner boiler (9) and the indoor heating circuit (10). The indoor heating circuit is similar to gas boilers and is designed specifically based on the type and number of floors of the house.

[0080] The aqua-ammonia burner boiler comprises two primary sections:

[0081] 1. Ammonia-Water Separator (11)

[0082] 2. Ammonia Burner (12)

[0083] To enhance the efficiency of the system, the water exiting the boiler can be utilized for additional home heating through a separate radiator (13).

[0084] Space Heating Applications

[0085] At each space target, the aqua-ammonia is fed into an aqua-ammonia heating boiler, which includes an aqua-ammonia separator and a high-efficiency combustion unit that oxidizes ammonia, providing consistent and safe space heating. The products of the combustion consist of water and nitrogen. The water produced from combustion and the separation system, if not needed, can be discharged into drainage systems, municipal sewage, or through a dedicated pathway for this system.

[0086] In the mentioned boiler, ammonia must be separated from water, making the ammonia separator (11 ) a critical component. The aqua-ammonia burner boiler system can be designed in two configurations:

[0087] First Design (With Condenser):

[0088] This design includes a condenser and is suitable for cases with high fluctuations in energy consumption. It requires a large storage tank and allows for a longer residence time for pure ammonia in the tank. However, this increases the risk of moisture condensation during the ammonia storage process and even during combustion.

[0089] Second Design (Without Condenser):

[0090] In this configuration, the condenser is eliminated, making it ideal for cases of continuous energy consumption where moisture removal is unnecessary.

[0091] Figures 2 and 3 illustrate the two separation designs with and without a condenser, respectively.

[0092] Figure 2 illustrates the Aqua-Ammonia heating boiler (With Condenser) system (9), which comprises the following components: a water-ammonia separator (14), a condenser (15), an ammonia-air storage tank (16), a pure air pump (17), an air-ammonia pump (18), an air-ammonia burner blower (19), an ammonia burner (20), a water-water heat exchanger (21 ), and an exhaust-water heat exchanger (22).

[0093] The aqua-ammonia mixture first enters the condenser (15) from pipe (23), where it is preheated. This process causes the condensation of moisture present in the exhaust gas from the separator. The exhaust gases from the burner (20) pass through the center of the separator, transferring a portion of their heat to the separator. Finally, after passing through heat exchanger (22), the remaining heat is transferred to the working fluid of the heating system, and the gases exit through outlet (25).

[0094] The purified water from the separator, after the separation process, enters heat exchanger (21), where it transfers the heat absorbed duringthe separation process to the working fluid of the heating system. Ultimately, the cooled water exits the system through pathway (24) and is discharged from the boiler system.

[0095] The working fluid of the heating system enters the first heat exchanger (21) through pipe (26). After absorbing heat from the purified water in exchanger (22) and coming into contact with the exhaust gases, the heated working fluid is directed to point (27), from where it flows toward the radiators of the residential or commercial heating system.

[0096] Figure 3 illustrates the boiler system without a condenser. In this boiler, the condenser (15) is removed, and the recuperator heat exchanger (28) is used to preheat the incoming ammonia-water mixture. In this system, the ammonia and a portion of the evaporated water are directed to the storage tank and, ultimately, to the burner.

[0097] Figure 4 depicts the condenser (15), where the aqua-ammonia enters through inlet (23) and, after heating, exits through into the separator (14). The separated gas enters at this stage through inlet (29), and after cooling and condensing the moisture, a dry mixture of ammonia and air ultimately exits through outlet (30). The condensed moisture returns gravitationally to the separator tank through the same inlet (29).

[0098] The amount of aqua-ammonia entering the separator tank is controlled with the help of valve (31 ) installed at outlet (28).

[0099] The condenser has two sections: a water-cooled condenser (32) and an air-cooled condenser(33).

[0100] Figure 5 shows the ammonia separator tank (14), which includes an electric heater (34), porous plates (35), pure air injection (36), and air-ammonia injection in circulation (37). The main tank consists of two or more tiers, with porous separator plates (35) between them. High-concentration ammonia-water is injected into the tank through the upper inlet (28), and the condensed water containing ammonia from the condenser returns to the separator through inlet (29). The aqua-ammonia, upon contact with the warm walls and while passingthrough the tiers and porous plates, reaches its boiling point, resulting in the complete evaporation of ammonia and some water. The injected air from the lower tiers carries these evaporated gases, and ultimately, the ammonia-air gas along with some moisture exits through outlet (29). In the end, nearly pure and warm water exits through outlet (38). The injected pure air at the lowest tier (36) will have the highest ammonia absorption.

[0101] The ammonia burner consists of an ammonia-air burner (20) and secondary air, with hot combustion products passing through the central duct of the separation system, providing some of their energy to the separation system. Ultimately, the combustion gases are directed to the exhaust-water heat exchanger (22) to heat the water in the heating cycle through exit (39). To improve combustion and reduce temperature, it is necessary to inject excess air into the burner.

[0102] In this system, the ammonia burner itself acts as the separation generator. To facilitate startup and better control, an electric heater (34) is included to assist the burner during unstable conditions. The nature of the porous medium and its permeability, along with the amount of circulating air, control the fluid retention time within the separator.

[0103] Figure 6 illustrates the ammonia-air storage tank (16). The dried ammonia-air enters the tankthrough duct (40). Since ammonia is lighter, it accumulates atthe top, while heavier air collects atthe bottom. This tank features a membrane (41 ) that separates it into upper and lower sections. This membrane allows better airflow than ammonia, resulting in lower purity air in the lower section. Higher purity air is sent from the tank to the midseparator section through the lower duct (42) by the air-ammonia pump (18). This circulation helps direct the separated ammonia toward the ammonia storage tank. From the upper outlet (43), ammonia, along with a small concentration of air, is sent to the burner.

[0104] The ultimate goal of the aqua-ammonia heating boiler is to provide the necessary heating for residential space. The output of this system consists of two heated fluids: nearly pure hot water exiting the separator (38) and combustion products from the exhaust (39). As shown in Figure 1 and 2, these two fluids transfertheir heatto the circulating water in the residential heating system, e.g. radiators through two heat exchangers (the water- water heat exchanger (21 ) and the exhaust-water heat exchanger (22)), thereby indirectly supplying heat to the residential unit.

[0105] Power Generation Applications

[0106] The system may include the establishment of an aqua-ammonia production unit, where ammonia is mixed with water to create the fuel. The aqua ammonia can then be transported either through existing natural gas pipelines or via a dedicated pipeline to the aqua-ammonia power plant, which first separates ammonia from water based on the same novel separation method. The pure ammonia then fuels the ammonia-powered power generation system, such as ammonia gas turbines, internal combustion engines, or ammonia-based fuel cells. The exhaust products can provide the required thermal energy for separating ammonia from water.

[0107] Figure 7 illustrates the layout of the aqua-ammonia production unit (1 ), fuel transmission pipelines (2), and the aqua-ammonia power plant system (44).

[0108] The aqua-ammonia power plant, comprises two main components: the ammonia separator (45) and the ammonia-powered engine (46). In this system, the thermal energy from the water output of the separator and the engine exhaust can be captured using separate heat exchangers (47, 48), enabling a combined heat and power generation system. A key aspect of the separator system is the requirement for thermal energy. The interaction between the ammonia-powered engine (46) and the separator system to ensure a stable fuel supply is critical. The simplest method to supply this thermal energy is by utilizing the exhaust gases (49) and combustion by-products from the engine.

[0109] Figures 8 to 11 illustrate the integration of this system with various configurations, including internal combustion engines (gasoline and diesel) (50), gas turbines (51 ), steam cycles (52), boilers (53), and fuel cells (54). For fuel cells, depending on the fuel cell engine technology (ammonia-fueled or hydrogen-fuelled), an ammonia cracker unit (55) may be required.

[0110] Given the relatively low temperature range required for separation (90-140°C), another approach to supply the necessary thermal energy is to use the engine cooling system (56), which is commonly available in internal combustion engines. Figure 12 demonstrates this concept for internal combustion engines.

[0111] In this system, ammonia must be separated from water, making the ammonia separator (45) a critical component. The system can be designed in two configurations:

[0112] First Design (With Condenser):

[0113] This design includes a condenser and is suitable for cases with high fluctuations in energy consumption. It requires a large storage tank and allows for a longer residence time for pure ammonia in the tank. However, this increases the risk of moisture condensation during the ammonia storage process and even during combustion.

[0114] Second Design (Without Condenser):

[0115] In this configuration, the condenser is eliminated, making it ideal for cases of continuous energy consumption where moisture removal is unnecessary.

[0116] The separation method and components for power applications are similarto those used in heating systems, with the only difference being that the mentioned engines replace the burner (20). The exhaust heat or waste heat from the engine is directed to the separator unit (14).

[0117] Figure 13 illustrates a schematic for a method (1300) of utilising aqua-ammonia as a power source. The method (1300) comprises: supplying (1310) aqua-ammonia to a distillation separator (14); separating (1320) the aqua-ammonia using the distillation separator (14) to produce gaseous distillation products comprising ammonia; burning (1340) the gaseous distillation products to produce hot combustion products; and utilising (1350) the hot combustion products to transfer heat and / or power.

[0118] Utilising (1350) the hot combustion products may comprise supplying the hot combustion products to a heat exchanger to provide space heating for a domestic or industrial setting. It may comprise using the hot combustion products to drive a turbine (51 ) to generate energy, or as part of an internal combustion engines (gasoline and diesel) (50), steam cycles (52), boilers (53), and fuel cells (54

[0119] The method (1300) may further comprise utilising (1345) the hot combustion product to provide heat to the distillation separator. This may comprise directing the hot combustion products through an exhaust pipe that passes through the centre of the separator (14).

[0120] The method (1300) may further comprise dehumidifying (1325) the gaseous distillation products with a condenser (15).

[0121] The method (1300) may further comprise storing (1330) the gaseous distillation products in an air-ammonia storage tank (16).

[0122] Aqua ammonia fuel may be generated and transported as part of the method (1300) of power generation. The generation step (1301) comprises mixing ammonia with water to produce aqua-ammonia, in an aqua-ammonia production unit (1 ). Transporting (1305) the aqua-ammonia fuel comprises either utilisation of existing natural gas infrastructure or a dedicated pipeline.

[0123] The following clauses, which are not claims, may define or discuss one or more aspects or embodiments of the present inventions

[0124] 1 . In "Carbon-Free Energy Delivery Through Low-Pressure Pipework," a fuel transfer system based on aqua-ammonia is described, which can be used in “Aqua-ammonia heating boilers” forspace heatingorfor powergeneration in internalcombustion engines, gas turbines, fuel cells, or any system capable of burning ammonia.

[0125] 2. Aqua-ammonia, as introduced in clause 1 as a fuel, is produced by combining ammonia with water in a production unit, transported through transmission pipelines that could be either the adapted existing gas infrastructure or dedicated pipeline to the target space, where ammonia is subsequently separated from water and oxidized within a combustion unit to generate thermal energy for effective space heating or to generate power.

[0126] 3. The "Aqua Ammonia Heating Boiler," as described in Clause 1 , can operate in two configurations: with a condenserfor cases where the burner is sensitive to fuel moisture, and without a condenserfor cases where the burner is not sensitive to moisture and fuel consumption is continuous.

[0127] 4. The "Aqua Ammonia Heating Boiler with condenser " as described in Clause 3, comprising a condenser system, an aqua-ammonia separator, an ammonia-air storage tank, a pure air pump, an air-ammonia pump, an air-ammonia burner pump, an ammonia oxidizer, a water-water heat exchanger, and an exhaust-water heat exchanger.

[0128] 5. The condenser introduced in Clause 4 is configured to preheat the incoming aqua- ammonia and dehydrate the generated ammonia gas; wherein the aqua-ammonia, delivered via urban pipelines as specified in Clause 2, enters the condenser and interacts with heated ammonia gas and moisture from the separator outlet described in Clause 4; the condenser comprises an exchanger with aqua-ammonia on the outer wall and a coiled interior pipe carrying ammonia gas, air, and moisture, where a portion of the coil extends outside the exchanger for air contact, with the condenser installed horizontally to facilitate condensate return to the separator tank.

[0129] 6. The separator introduced in Clause 4 separates ammonia from water using thermal energy and comprises an annular tank. A multi-stage separation system for A-A includes two or more cavities arranged in a vertical stack, a source of heat where a hot gas, such as burner exhaust gases, moves through the centre of the separation system and exchanges heat with all the cavities, a set of porous separators configured to separate each pair of adjacent cavities, wherein each porous separator supports liquid in the upper cavity while allowing gas from the lower cavity to bubble through the liquid in the upper cavity. The system also includes a set of tubes configured to enable some liquid content from each cavity above the lowest cavity to be pumped or otherwise directed to flowthrough one or more tubes into the cavity immediately below, a blowerto supply air into the lowest cavity to create a monotonic pressure drop between the lowest and the uppermost cavities, ensuring continuous gas flow from the lower cavity to the upper cavity in each pair, a supply tube feeding A-A into the uppermost cavity, a water draw-off tube at a low point in the lowest cavity, and a draw-off tube at a high point in the uppermost cavity to extract a mixture of air, water vapor, and ammonia. The extracted mixture is then directed eitherto the condenser described in Clause 5.

[0130] 7. The porous plates described in Clause 6 permits the downward flow of aqua- ammonia while allowingair, ammonia, and any generated vaporto move upward, thereby enhancing the contact surface between water and air and improving heat transfer efficiency.

[0131] 8. The ammonia-air storage tank introduced in Clause 4 is a cylindrical tank divided into two sections by a membrane. Dried ammonia-air from the condenser described in Clause 5 enters the middle of the tank. An upper outlet is provided for ammonia extraction, which connects to a gas pump for delivery to the burner, while a lower outlet supplies air with reduced ammonia content to an air pump for injection into the midsection of the separator tank.

[0132] 9. The storage tank described in Clause 8 is equipped with measures to enhance the separation efficiency, such that the natural density difference between air and gaseous ammonia causes the concentration of ammonia at the bottom of the tank to be lower than that at the top of the tank. Additionally, a filter can be positioned within the middle of the tank to enhance the concentration difference between the bottom and the top of the tank. A blower is also provided for returning some low-concentration air-ammonia mixture into the second-lowest cavity in the multi-cavity stack of the separator introduced in Clause 6. The fuel with an appropriate air percentage is then transferred from the top of the tank to the burner introduced in Clause 4.

[0133] 10. The membrane described in Clause 8 is designed to preferentially allow the passage of air while significantly restricting the flow of ammonia. 11. The ammonia burner may be separate from the separation system, and after burning the ammonia, the produced combustion gases can ultimately be transferred to the separation center. Alternatively, the burner can be positioned at the center of the separator from Clause s, receiving its ammonia-air mixture from the ammonia-air storage tank in Clause 8, with secondary air injected around the burner via an air pump to enhance combustion efficiency.

[0134] 12. The heat and exhaust produced in the burner introduced in Clause 11 can be fully or partially utilized for the separation process, with the remaining portion being used for other applications, including heating.

[0135] 13. The fresh air pump, as introduced in Clause 4, supplies fresh air to both the separation system and the secondary air for the burner, connecting the fresh air intake from the environment to the lowest cavity of the separator introduced in Clause 6 and the burner outlined in Clause 11 .

[0136] 14. The ammonia-air pump specified in Clause 4 delivers the ammonia-air mixture to the primary section of the burner detailed in Clause 11 , with its inlet connected to the top of the ammonia storage tank described in Clause 9 and its outlet directed to the burner.

[0137] 15. The circulating air-ammonia pump referenced in Clause 4 provides airflow for circulation within the separator system, with its inlet connected to the lower section of the ammonia storage tank and its outlet leading to the second cavity of the separation system mentioned in Clause 6.

[0138] 16. The water-water heat exchanger is of the brazed plate type, wherein the hot water output from the separation subsystem described in Clause 6 enters one side of the exchanger, while the other side is in contact with the hot water from the residential heating system, thereby increasing its temperature.

[0139] 17. The exhaust-water heat exchanger is also of the brazed plate type, where the combustion gases exiting the separator referenced in Clause 6 enter one side of the exchanger, and the hot water from the heating system, which flows out from the exchanger described in Clause 16, comes into contact with the other side, thereby heating the water.

[0140] 18. The required heat for the radiators in the residential unit is supplied by the two heat exchangers mentioned in Clauses 16 and 17.

[0141] 19. The electric heater is installed inside the separator introduced in Clause 6. The electric heater operates in conjunction with the burner to heat the water in the separator and activates duringstartup or system fluctuations, aiding in the continuous operation of the system.

[0142] 20. In the Aqua Ammonia Heating Boiler without a condenser, the recuperator replaces the condenser and performs the preheating of the aqua-ammonia. The ammonia gas and air produced in the separator are directly routed to the storage tank, and the rest of the process proceeds similarly to the previous configuration. A recuperator is also installed that can recover most of the above-ambient-temperature heat from the water drawn off the bottom of the multi-stage stack, supplying that above- ambient-temperature heat into the incoming aqua-ammonia stream.

[0143] 21. The proposed design of the "Aqua Ammonia Heating Boiler" enables superior energy transfer compared to hydrogen and natural gas while employing a water absorbent that significantly reduces the toxicity and corrosiveness associated with ammonia, resulting in the combustion of a cleaner fuel that enhances safety and environmental sustainability.

[0144] 22. The system allows for controlled separation efficiency and energy release by adjusting the heating of the separator and regulating the input ratio of aqua-ammonia, thereby enhancing the system's flexibility and efficiency in energy production.

[0145] 23. A multi-stage separation system for A-A as described in clause 6 in which there is also provided within the air-ammonia tank a flame-suppressant such as a sparse steel mesh to prevent rapid ignition of the tank contents even if one part of the tank was to become very hot.

[0146] 24. In the systems introduced in Clause 3, the thermal separation method, as part of the AA heating boiler, not only provides heating but also produces purified water that can be used locally or safely drained; since this water is generated through distillation from the ammonia separation process, it is suitable for drinking, effectively functioning as a small-scale desalination system.

[0147] 25. The heating system introduced in Clause 3 can operate in a centralized manner outside homes or residential complexes for environmental or security reasons, with the produced hot water eventually being transferred to homes and residential units.

[0148] 26. The power generation system utilizing aqua-ammonia as described in Clause 1 is an ammonia-based power generation system that obtains its ammonia from the tank specified in Clause 8, harnessing the exhaust heat and output of the engine (combustion engines, gas turbines, fuel cells, or any system capable of burning ammonia) to energize the separation system outlined in Clause 6, while deactivating the burner of this system.

[0149] 27. In addition to the exhaust gases, the hot water from the cooling system of these engines can also be used to provide the separation heat for power generation applications. The hot fluid (whether exhaust gas or cooling system water) serves as the heat source for the separation process described in Clause 6.

[0150] 28. The system introduced in Clause 26 simultaneously generates both heat and power, functioning as a Combined Heat and Power (CHP) system.

Claims

CLAIMS1 . An energy delivery system using aqua-ammonia as a fuel source, the system comprising: an aqua-ammonia distillation separator configured to separate the aqua- ammonia into water and a gaseous distillation product comprising ammonia; an ammonia-air storage tank configured to store the ammonia generated by the aqua-ammonia distillation separator; and an ammonia burner configured to burn the ammonia to produce hot combustion products for use in heat and / or power generation.

2. The energy delivery system of claim 1 , wherein the aqua-ammonia distillation separator comprises: a distillation tank; a heat source disposed within the distillation tank configured to heat the aqua- ammonia; one or more porous plates disposed within the distillation tank to separate the distillation tank into tiers, each of the one or more porous plates configured to support liquid whilst allowing passage of gases such that gas may bubble through any liquid supported by each of the one or more porous plates; a first inlet fluidly connected to the distillation tank and configured to provide aqua-ammonia into the distillation tank; a second inlet fluidly connected to the distillation tank, and configured to provide an airstream into the tank, a first outlet for outputting gaseous distillation products; and a second outlet for discharging distilled water; wherein: the first inlet and first outlet are disposed above the one or more porous plates; and the second inlet and second outlet are disposed below the one or more porous plates, such that the airstream from the second inlet creates a pressure differential and carries evaporated gases from the distillation tank up to the first outlet.

3. The energy delivery system of claim 2, wherein the aqua-ammonia distillation separator further comprises: a third inlet fluidly connected to the distillation tank, and configured to provide an airstream into the tank, wherein the third inlet is disposed below the first inlet such that the airstream from the third inlet creates a pressure differential and carries evaporated gases from the distillation tank up to the first outlet.

4. The energy delivery system of claim 2 or claim 3, wherein the heat source comprises: an exhaust pipe passing through the distillation tank, the exhaust pipe configured to carry the hot combustion products from the ammonia burner such that the hot combustion products provide a heat source for the distillation.

5. The energy delivery system of any of claims 2 to 4, wherein the heat source comprises an electric heater disposed within the distillation tank.

6. The energy delivery system of any preceding claim, further comprising: a heat exchanger through which the hot combustion products flow, such that heat is transferred from the hot combustion products to a working fluid of a heating system.

7. The energy delivery system of claim 2 or any of claims 3 to 6 as dependent on claim 2, further comprising: a secondary heat exchanger through which water discharged from the second outlet flows, such that heat is transferred from the discharged water to a working fluid of a or the heating system.

8. The energy delivery system of any preceding claim, further comprising: a condenser fluidly connected between the separator and the storage tank, the condenser configured to receive the gaseous distillation product and dehumidify from the gaseous distillation product.

9. The energy delivery system of claim 8, wherein the condenser comprises: an interior pipe through which the gaseous distillation product flows in use; andan aqua-ammonia well configured to receive aqua-ammonia in use and fluidly connected to the separator such that an outlet of the well comprises an aqua-ammonia inlet into the separator; wherein the exterior surface of the interior pipe interfaces with the well such that heat is transferred from the gaseous distillation product to the aqua-ammonia fuel in use.

10. The energy delivery system of claim 9, wherein: the interior pipe is coiled vertically, such that condensed moisture exits the interior pipe under the action of gravity.11 . The energy delivery system of any of claims 1 to 7, further comprising: a recuperator heat exchanger through which, in use, aqua-ammonia fuel flows prior to distillation, and distilled water flows post-distillation, such that heat is transferred from the distilled water to the aqua-ammonia fuel.

12. The energy delivery system of any preceding claim, wherein the air-ammonia storage tank comprises: a tank body; a first storage inlet to receive the gaseous distillation products; a separation membrane configured to separate the tank body into upper and lower sections, wherein the membrane restricts the flow of ammonia from the upper to lower sections; a first outlet disposed above the separation membrane to receive outgoing ammonia; and a second outlet disposed below the separation membrane to receive outgoing air.

13. The energy delivery system of any preceding claim, wherein the air-ammonia storage tank comprises a flame suppressant.

14. The energy delivery system of any preceding claim, further comprising: one or more sensors configured to determine one or more of: i. volume of aqua-ammonia within the separator;ii. temperature of the separator; iii. temperature of separated water; iv. pressure within the air-ammonia storage tank v. where present, temperature of any working fluid of a heating system; and a controller, the controller configured to regulate one or more of: i. the temperature of the separator; ii. flow of aqua-ammonia fuel into the separator iii. flow of air and / or air-ammonia into the ammonia burner; iv. flow of ammonia into the ammonia burner; v. flow of separated water into a heat exchanger; vi. flow rate of hot combustion products into a heat exchanger, turbine or other working system.

15. The energy delivery system of claim 14 as dependent directly or indirectly on claim 4, wherein: the controller is configured to regulate one or more of: bi. the flow rate of the hot combustion products through the separator.

16. The energy delivery system of any preceding claim, further comprising: an aqua-ammonia production unit; and aqua-ammonia transmission means, comprising pipelines arranged to transport the aqua-ammonia produced in the aqua-ammonia production unit to the aqua- ammonia distillation separator.

17. The energy delivery system of claim 16, wherein at least some of the aqua- ammonia transmission means utilises pre-existing natural gas infrastructure.

18. A method of utilising aqua-ammonia as a power source, the method comprising: a. supplying aqua-ammonia to a distillation separator;b. separating the aqua-ammonia with the distillation separator to produce gaseous distillation products comprising ammonia; b. optionally storing the gaseous distillation products; c. burning the gaseous distillation products to produce hot combustion products; d. utilising the hot combustion products to transfer heat and / or power.

19. The method of claim 18, further comprising the step of: di. utilising the hot combustion product to provide heat to the distillation separator.

20. The method of claim 18 or claim 19, further comprisingthe steps of: bi. after separating the aqua-ammonia, dehumidifyingthe gaseous distillation products with a condenser.21 . The method of any of claims 18 to 20, further comprising: i. mixing ammonia with waterto produce aqua-ammonia in an aqua- ammonia production unit.

22. The method of any of claims 18 to 21 , wherein supplying aqua-ammonia comprises either utilisation of existing natural gas infrastructure or a dedicated pipeline.

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