Blending combustion and tail gas treatment integrated system based on solid-state ammonia storage

Abstract

The invention belongs to the technical field of energy and environmental protection engineering, and relates to a mixed combustion and tail gas treatment integrated system based on solid-state ammonia storage. The system is composed of three core parts: firstly, a metal halide-graphene aerogel composite material is adopted as an adsorbent to realize efficient adsorption and desorption circulation of ammonia; secondly, the desorption process of ammonia is driven through engine cylinder cover water circulation; and finally, an ammonia-doped combustion technology and a tail gas treatment technology are integrated to form a complete system. Compared with the prior art, efficient storage of ammonia is achieved, the stored ammonia is used for blending combustion and tail gas treatment, emission of greenhouse gas is reduced, and a more environment-friendly and low-cost solution is provided for energy conservation and emission reduction of medium and heavy fuel vehicles.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy and environmental protection engineering, and in particular relates to a comprehensive system of mixed combustion and tail gas treatment based on solid ammonia storage. Background Art

[0002] In my country's transportation sector, diesel trucks are the backbone of the logistics system. However, the widespread use of diesel trucks has caused a lot of tail gas pollution, and its carbon dioxide emissions account for about 20.8% of the total motor vehicle emissions; in the total motor vehicle nitrogen oxide emissions, diesel trucks account for as high as 78.1%. Therefore, it is urgent to solve the pollution problem of diesel trucks. Electrification is a means to achieve energy conservation and emission reduction for trucks. Due to the high cost of batteries, the purchase cost of electric trucks is usually 20% to 40% higher than that of traditional fuel trucks. In addition, electric trucks charge slowly and usually take several hours to fully charge. At the same time, the cruising range of electric trucks is relatively short, and most vehicles have a driving range of between 80 and 350 kilometers, which is still far less than the driving capacity of traditional diesel trucks.

[0003] Currently, ammonia is widely studied as a fuel in fuel cells. In solid oxide fuel cells and proton ceramic fuel cells that directly utilize ammonia, the optimal power density is greater than 1.2 W / cm 2 , which is comparable to hydrogen fuel cells. In addition, ammonia is used in different types of engines such as spark plug ignition engines, compression ignition engines, and gas turbines, providing opportunities for sustainable energy supply for internal combustion engines and gas turbines. Since the octane number of ammonia is as high as 130, using ammonia as an engine fuel can achieve a very high compression ratio, thereby obtaining higher thermal efficiency. On the other hand, ammonia is also used as a reducing agent in selective catalytic reduction (SCR) technology. The ammonia of traditional SCR technology comes from urea aqueous solution, which has the problems of low urea storage density and easy crystallization at low temperatures.

[0004] Patent CN206338105U provides a solid-state SCR system reductant supply device, which uses the heat of vehicle exhaust to heat the solid-state ammonia storage tank without the need for additional heating equipment. This design allows a set of solid-state ammonia storage tanks to have a service life of more than 10,000 kilometers, which has significant advantages in terms of mileage and cost-effectiveness. The device is filled with strontium chloride as an adsorbent. However, the patent does not clearly state the mileage that can be covered by a single injection of ammonia, nor does it elaborate on the specific operating procedures for filling ammonia. In addition, the selection of strontium chloride as an adsorbent without combining it with a porous medium material may result in low adsorption and desorption efficiency, and its desorption rate may not meet the needs of treating exhaust gas. At the same time, the device only uses the stored ammonia to treat exhaust gas, and its use is relatively single, and it is still difficult to significantly reduce harmful gas emissions.

[0005] Patent application CN117404190A discloses a dual-fuel engine system and its control method, and a car. The dual-fuel engine system includes an ammonia fuel supply unit, a gasoline fuel supply unit, a heat exchange unit, a control unit, and an engine; the ammonia fuel supply unit is used to transfer ammonia fuel to the engine; the gasoline fuel supply unit is used to transfer gasoline fuel to the engine; the heat exchange unit is arranged in the exhaust pipe of the engine; the ammonia fuel supply unit includes a liquid ammonia storage subunit and an ammonia gasification subunit, and the ammonia gasification subunit is connected to the liquid ammonia storage subunit and the heat exchange unit respectively; the control unit is used to control the first temperature liquid ammonia provided by the liquid ammonia storage subunit to be transferred to the ammonia gasification subunit, and control the first temperature liquid ammonia to be transferred to the heat exchange unit, so that the second temperature liquid ammonia after heat exchange is gasified in the ammonia gasification subunit and then transferred to the engine; it solves the problem that the exhaust heat in the existing dual-fuel engine system is not fully utilized and the energy consumed by liquid ammonia gasification is high. In this patent application, ammonia is stored in the form of liquid ammonia, which puts forward more stringent conditions than solid ammonia storage. The unique physical properties of liquid ammonia require storage equipment to have excellent refrigeration and thermal insulation performance as well as pressure and corrosion resistance, which significantly increases the cost of related equipment. In addition, the inherent strong toxicity and corrosiveness of liquid ammonia means that once a leak occurs, it may have serious consequences for human health and environmental safety. The material specifications of storage equipment are very high, and additional precautions must be implemented to ensure absolute safety, which will inevitably increase very high costs.

[0006] Patent CN102733913B provides a post-processing control unit for ammonia storage and supply in a two-stage waste heat mode, which is heated by the waste heat of the engine coolant, and relies on a control unit and a set of solenoid valves or proportional valves to achieve ammonia dosage delivery and convenient introduction into the SCR post-processing system to achieve NOx removal; simplify the system and improve reliability. It is used in the SCR post-processing industry of automobile exhaust and is also applicable to the FCEV energy storage system of fuel cells. However, the patent has deficiencies in functional comprehensiveness, complexity of system design and economy. The patent mainly focuses on the adsorption and storage process of ammonia, lacks a comprehensive description of ammonia release and utilization, and fails to effectively integrate ammonia combustion and tail gas treatment, thereby limiting its overall efficiency. Although advanced adsorbent materials are used in the patent, the preparation and use costs of these materials may be high, and the storage conditions are strictly required, resulting in reduced economy. In addition, the patent does not directly treat the tail gas generated after the combustion of ammonia, and fails to effectively reduce the impact on the environment. Patent application CN110500162A discloses a diesel engine exhaust aftertreatment SCR ammonium bicarbonate injection system, which consists of two large bottles, one small bottle, an SCR controller and an engine ECU. The large bottle is filled with solid anhydrous ammonium bicarbonate dry material. The large bottle has a heating pipe connected to the engine water outlet pipe. The ammonium bicarbonate in the large bottle is heated to pyrolyze to produce ammonia, carbon dioxide and water. The gas produced after pyrolysis is pumped into the small bottle through a diaphragm pump in the SCR controller through a one-way valve and stored in the small bottle. The entire pipeline is a mixture of gaseous ammonia, carbon dioxide and water vapor. The mixed material sprayed into the exhaust pipe is heated by the high temperature of the engine exhaust and instantly releases gaseous ammonia. Ammonia reduces NOx to harmless nitrogen and water, and the ammonium bicarbonate is always in a dry state. This patent application solves the problem of urea crystallization and the inability of urea to treat NOx when the engine exhaust temperature is lower than 160 degrees. However, this patent application has deficiencies in the comprehensiveness of overall functions and system integration. The patent mainly focuses on the storage and release of ammonia. Although it provides certain technical innovations, it lacks comprehensive consideration of ammonia combustion and its tail gas treatment, which limits its flexibility and efficiency in practical applications. In addition, the ammonia storage materials in the patent may face high costs and strict requirements on the operating environment, resulting in relatively low economic efficiency. Therefore, the competitiveness of this technical solution in practical applications is relatively weak. Summary of the invention

[0007] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and to provide a comprehensive system of mixed combustion and exhaust gas treatment based on solid ammonia storage. The system can simultaneously carry out mixed combustion and exhaust gas treatment, ensure stable ammonia supply around the clock with lower cost and higher safety, and effectively reduce exhaust nitrogen oxides and carbon emissions.

[0008] The purpose of the present invention can be achieved by the following technical solutions:

[0009] The present invention provides a comprehensive system for blending combustion and tail gas treatment based on solid ammonia storage, comprising a solid ammonia storage unit component, a high-temperature cylinder head water-driven ammonia desorption working cycle component and a blending combustion and tail gas treatment cycle component; wherein the solid ammonia storage unit component comprises a solid ammonia storage unit, using a metal halide-graphene aerogel composite material as an adsorbent for adsorbing and storing ammonia; the high-temperature cylinder head water-driven ammonia desorption working cycle component comprises an engine; the blending combustion and tail gas treatment cycle component comprises an SCR unit;

[0010] When the engine is running, water from the engine cylinder head enters the solid ammonia storage unit, causing the adsorbent to undergo a desorption reaction. Part of the desorbed ammonia is mixed with air and enters the engine cylinder for mixed combustion. The other part of the ammonia is mixed with the exhaust gas to be treated and enters the SCR unit. Ammonia undergoes an oxidation-reduction reaction with NOx to generate N 2 and H 2 O, eliminating NOx; at the same time, the flue gas waste heat generated by the vehicle during operation is used for ammonia desorption in the solid ammonia storage unit (1), thereby making full use of the flue gas waste heat resources.

[0011] Furthermore, the solid-state ammonia storage unit assembly also includes a first ammonia valve, a second ammonia valve, a first cylinder cover water valve and a second cylinder cover water valve; the engine cylinder cover water is connected to two cylinder cover water pipelines, one of which is a cylinder cover water inlet pipe, on which a first cylinder cover water valve is arranged, and the engine cylinder cover water enters the solid-state ammonia storage unit through the cylinder cover water inlet pipe, and the other is a cylinder cover water outlet pipe, on which a second cylinder cover water valve is arranged, and the engine cylinder cover water after heat exchange in the solid-state ammonia storage unit returns to the engine through the cylinder cover water outlet pipe; the solid-state ammonia storage unit is connected to the SCR unit through two pipelines, one pipeline is provided with a first ammonia valve, and the other pipeline is provided with a second ammonia valve.

[0012] Furthermore, during the high-temperature cylinder cover water-driven ammonia desorption working cycle, the engine's waste heat recovery, output heating capacity, and ammonia desorption process control are based on the truck's load and driving speed. These parameters directly affect the engine cylinder cover water circulation rate and the injection flow of diesel and ammonia, ensuring the efficiency and stability of the integrated system of mixed combustion and exhaust gas treatment based on solid ammonia storage.

[0013] Furthermore, in the metal halide-graphene aerogel composite material, the mass ratio of metal halide to graphene aerogel is 1:1 to 5:1, and the metal halide is selected from at least one of strontium chloride or calcium chloride.

[0014] Furthermore, the solid-state ammonia storage unit is composed of a plurality of reactors, each of which is composed of a shell and a plurality of unit tubes tightly arranged in the shell, a water pipe is passed through the unit tube, and the water pipes in each unit tube are connected in parallel to form a water circulation channel in the reactor, and the cavity between each unit tube and the water pipe is filled with the metal halide-graphene aerogel composite material for adsorbing and storing ammonia.

[0015] Furthermore, the step of filling the metal halide-graphene aerogel composite material is: injecting a mixed liquid of metal halide and graphene into the cavity between each unit tube and the water pipe, then introducing low-temperature liquid nitrogen into the unit tube to make the mixed liquid of metal halide and graphene freeze quickly, and ice crystals grow from the outer wall of the water pipe to the surrounding area. After the mixed liquid is completely frozen, it is vacuum dried and thermally reduced to finally form a layered structure composite adsorbent fin filled in the water circulation channel.

[0016] Furthermore, the mixed combustion and exhaust gas treatment cycle component also includes a third ammonia valve, a first ammonia nozzle, a turbocharger, an intercooler, a DOC unit, a DPF unit, a second ammonia nozzle, an oil pump, a fuel tank and a third ammonia nozzle; the first ammonia nozzle is connected to the solid ammonia storage unit through a pipeline provided with the first ammonia valve, and a third ammonia valve is arranged on the pipeline; the second ammonia nozzle is connected to the solid ammonia storage unit through a pipeline provided with the second ammonia valve; the turbocharger is divided into two paths, one of which is connected to the third ammonia nozzle through the intercooler, and the other is connected to the DOC unit, the DPF unit and the SCR unit in sequence, and the fuel tank is connected to the oil pump and the third ammonia nozzle in sequence through a pipeline;

[0017] A part of the ammonia desorbed from the solid ammonia storage unit assembly is sprayed out through the first ammonia nozzle, mixed with the exhaust gas to be treated and then enters the turbocharger, and a part of the gas after supercharging is cooled by the intercooler and then enters the third ammonia nozzle; the third ammonia nozzle sprays each material into the engine for mixed combustion, and the remaining ammonia desorbed from the solid ammonia storage unit assembly enters the second ammonia nozzle; another part of the gas after supercharging by the turbocharger is processed by the DOC unit and the DPF unit in turn, and then enters the SCR unit, and is processed in the SCR unit together with the ammonia sprayed from the second ammonia nozzle.

[0018] Furthermore, inside the engine, the ammonia and diesel mixture undergoes a process of compression, combustion expansion and recompression to drive the normal operation of the engine. The mixing energy ratio of ammonia and diesel injected into the engine for combustion is 10% to 80%. Precisely adjusting the ratio of ammonia and diesel for mixed combustion can effectively reduce exhaust emissions without reducing combustion efficiency.

[0019] Furthermore, the mixed combustion and exhaust gas treatment circulation component uses ammonia desorbed from the solid ammonia storage unit to treat the exhaust gas, which can effectively avoid system blockages that may be caused by crystallization of urea aqueous solution in a low-temperature environment, while effectively reducing exhaust nitrogen oxide emissions, thereby improving the overall efficiency and reliability of the comprehensive system of the present invention.

[0020] Furthermore, the high-temperature cylinder cover water driven ammonia desorption working cycle component makes full use of the waste heat generated during the operation of the engine to heat the cylinder cover water; as the water temperature rises, the high-temperature cylinder cover water enters the solid ammonia storage unit, promotes the breaking of the coordination bonds between the metal halide and the ammonia molecules, and desorbs the ammonia molecules from the adsorbent; after the desorption effect is completed, the cooled cylinder cover water returns to the cylinder cover of the engine and continues to absorb the heat emitted by the engine.

[0021] Furthermore, the system releases ammonia during the day and fills ammonia at night, including the following steps:

[0022] (a) Filling

[0023] Under standard atmospheric pressure, the critical temperature of ammonia desorption / adsorption of metal halides such as strontium chloride is 35.2°C. Taking advantage of the lower temperature at night, ammonia is charged into the solid ammonia storage unit at a pressure of 0.5MPa to 1.0MPa, so that the adsorbent can adsorb and store more ammonia, thereby reserving sufficient ammonia supply for daytime use needs;

[0024] (b) Desorption

[0025] During the day, when the engine is running, high-temperature cylinder cover water enters the solid ammonia storage unit, causing the adsorbent to desorb ammonia, thereby effectively meeting the demand for ammonia in vehicle operation and exhaust gas treatment.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] (1) The present invention provides a comprehensive system of blended combustion and exhaust gas treatment based on solid ammonia storage. The system cleverly combines solid ammonia storage technology, blended combustion mechanism and exhaust gas treatment process, aiming to play an important role in the fields of energy technology and environmental protection engineering. The system consists of three core parts: first, metal halide-graphene aerogel composite materials are used as adsorbents to achieve efficient adsorption and desorption cycles of ammonia; second, the engine cylinder cover water cycle is used to drive the ammonia desorption process; finally, the ammonia blended combustion technology and exhaust gas treatment technology are integrated to form a complete system. The system not only significantly reduces vehicle fuel consumption, but also eliminates the need to use urea, achieving a significant reduction in energy consumption and high efficiency of exhaust gas treatment.

[0028] (2) The present invention utilizes the waste heat generated during the operation of the engine to heat the cylinder head water, and thereby drives the ammonia desorption process in the solid ammonia storage unit, thereby effectively recovering the engine combustion waste heat, improving the comprehensive utilization efficiency of energy, reducing dependence on external energy, and reducing operating costs.

[0029] (3) The present invention uses metal halide-graphene aerogel composite adsorbent to store and release ammonia, thereby improving the ammonia desorption efficiency and optimizing the tail gas treatment process. This solid-state SCR system avoids the crystallization blockage problem that may occur in traditional urea SCR systems under low temperature conditions, while effectively reducing harmful gas emissions and being more environmentally friendly.

[0030] (4) The present invention uses a solid ammonia storage unit to store ammonia, which significantly improves storage stability and greatly reduces the possibility of ammonia leakage. Compared with the storage methods of gaseous and liquid ammonia, this method greatly reduces safety risks; in addition, the ammonia stored in the solid ammonia storage unit can be stably stored in a solid form under standard atmospheric pressure, without relying on high-pressure or extremely low-temperature storage equipment, thereby simplifying storage conditions and reducing costs.

[0031] (5) The present invention uses a metal halide-graphene aerogel composite adsorbent as a solid ammonia storage material. The composite adsorbent uses graphene aerogel as the core matrix to provide a solid skeleton and pore structure for the composite adsorbent. Combining the high specific surface area and high porosity of graphene aerogel and the efficient ammonia absorption characteristics of metal halides, the graphene aerogel is equipped with a metal halide with high ammonia absorption capacity, so that the composite adsorbent can allow a large number of ammonia molecules to pass through, fully react with the metal halide, and store a large amount of ammonia in the form of a complex, so as to achieve rapid filling and release of ammonia, and greatly improve the ammonia storage efficiency and overall thermal conductivity of the metal halide. At the same time, it can also prevent ammonia leakage caused by changes in external factors such as temperature and pressure during storage, ensuring the high stability and reliability of the storage process. The present invention realizes efficient storage of ammonia based on solid ammonia storage materials, and uses the stored ammonia for mixed combustion and exhaust gas treatment, reducing greenhouse gas emissions, and providing a more green, environmentally friendly and low-cost solution for energy conservation and emission reduction of medium and heavy-duty fuel vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a structural schematic diagram of the integrated system of mixed combustion and tail gas treatment based on solid ammonia storage of the present invention;

[0033] Figure 2 It is a structural schematic diagram of a solid ammonia storage unit of the integrated system of mixed combustion and tail gas treatment based on solid ammonia storage of the present invention;

[0034] Figure 3It is a structural schematic diagram of a cross section of a solid ammonia storage unit of a comprehensive system for mixed combustion and tail gas treatment based on solid ammonia storage of the present invention;

[0035] Figure 4 This is a simulated loading diagram of the integrated system of mixed combustion and exhaust gas treatment based on solid ammonia storage of the present invention.

[0036] Description of the markings in the figure:

[0037] 1-solid ammonia storage unit, 2-first ammonia valve, 3-first cylinder cover water valve, 4-second ammonia valve, 5-second cylinder cover water valve, 6-engine, 7-third ammonia valve, 8-first ammonia nozzle, 9-turbocharger, 10-intercooler, 11-DOC unit, 12-DPF unit, 13-SCR unit, 14-second ammonia nozzle, 15-oil pump, 16-oil tank, 17-third ammonia nozzle, 201-cylinder cover water inlet pipe, 202-ammonia outlet pipe, 203-cylinder cover water outlet pipe, 204-reactor, 301-unit pipe, 302-strontium chloride-graphene aerogel composite adsorbent fin, 3001-simulated loading solid ammonia storage unit, 3002-simulated loading exhaust treatment system. DETAILED DESCRIPTION

[0038] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0039] In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, the terms "first", "second", "third", etc. are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the use of such data can be interchangeable where appropriate, so that the embodiments of the present invention can be implemented in an order other than that illustrated or described herein, and the objects distinguished by "first", "second", "third", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects; the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0040] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the following implementation manners or examples, unless otherwise specified, functional components or structures are conventional components or conventional structures used in the art to achieve corresponding functions.

[0042] Example 1

[0043] The present invention provides a comprehensive system of blending combustion and tail gas treatment based on solid ammonia storage, which cleverly combines solid ammonia storage technology, blending combustion mechanism and tail gas treatment process, and aims to play an important role in the field of energy technology and environmental protection engineering. Figure 1 As shown, the integrated system includes a solid ammonia storage unit 1, a first ammonia valve 2, a first cylinder cover water valve 3, a second ammonia valve 4, a second cylinder cover water valve 5, an engine 6, a third ammonia valve 7, a first ammonia nozzle 8, a turbocharger 9, an intercooler 10, a DOC unit 11, a DPF unit 12, an SCR unit 13, a second ammonia nozzle 14, an oil pump 15, a fuel tank 16, and a third ammonia nozzle 17. By utilizing the engine cylinder cover water to drive the solid ammonia storage unit 1 to desorb ammonia, the system not only significantly reduces the vehicle fuel consumption, but also eliminates the need to use urea aqueous solution, achieving a significant reduction in energy consumption and high efficiency in exhaust gas treatment.

[0044] Please see again Figure 1 As shown, this embodiment provides a comprehensive system of blending combustion and exhaust gas treatment based on solid ammonia storage, including a solid ammonia storage unit component, a high-temperature cylinder head water-driven ammonia desorption working cycle component and a blending combustion and exhaust gas treatment cycle component; wherein the solid ammonia storage unit component includes a solid ammonia storage unit 1, which uses a metal halide-graphene aerogel composite material as an adsorbent for adsorbing and storing ammonia; the high-temperature cylinder head water-driven ammonia desorption working cycle component includes an engine 6; the blending combustion and exhaust gas treatment cycle component includes an SCR unit 13;

[0045] When the engine 6 is running, the water from the engine cylinder head enters the solid ammonia storage unit 1, causing the adsorbent to undergo a desorption reaction. Part of the desorbed ammonia is mixed with air and enters the engine cylinder for mixed combustion. The other part of the ammonia is mixed with the exhaust gas to be treated and enters the SCR unit 13. The ammonia undergoes an oxidation-reduction reaction with NOx to generate N 2 and H 2O, eliminate NOx; at the same time, the flue gas waste heat generated by the vehicle during operation is used for ammonia desorption in the solid ammonia storage unit 1, thereby making full use of the flue gas waste heat resources.

[0046] like Figure 1 , Figure 2 As shown, in this embodiment, the solid ammonia storage unit assembly also includes a first ammonia valve 2, a second ammonia valve 4, a first cylinder cover water valve 3 and a second cylinder cover water valve 5; the engine cylinder cover water is connected to two cylinder cover water pipelines, one is a cylinder cover water inlet pipe 201, on which the first cylinder cover water valve 3 is arranged, and the engine cylinder cover water enters the solid ammonia storage unit 1 through the cylinder cover water inlet pipe 201, and the other is a cylinder cover water outlet pipe 203, on which the second cylinder cover water valve 5 is arranged, and the engine cylinder cover water after heat exchange in the solid ammonia storage unit 1 returns to the engine 6 through the cylinder cover water outlet pipe 203; the solid ammonia storage unit 1 is connected to the SCR unit 13 through two pipelines, one pipeline is provided with the first ammonia valve 2, and the other pipeline is provided with the second ammonia valve 4.

[0047] In some specific embodiments, during the high-temperature cylinder cover water driven ammonia desorption working cycle, the engine waste heat recovery, output heating amount and ammonia desorption process control are based on the truck load and driving speed. These parameters directly affect the engine cylinder cover water circulation rate and the injection flow of diesel and ammonia, ensuring the high efficiency and stability of the operation of the integrated system of mixed combustion and exhaust gas treatment based on solid ammonia storage.

[0048] In some specific embodiments, in the metal halide-graphene aerogel composite material, the mass ratio of metal halide to graphene aerogel is 1:1 to 5:1, and the metal halide is selected from at least one of strontium chloride or calcium chloride.

[0049] In this embodiment, in the metal halide-graphene aerogel composite material, the mass ratio of metal halide to graphene aerogel is 3:1, and the metal halide is strontium chloride.

[0050] In this embodiment, the solid ammonia storage unit 1 in the solid ammonia storage unit assembly is filled with a strontium chloride-graphene aerogel composite material adsorbent, which uses graphene aerogel as a porous matrix to provide a solid skeleton and pore structure for the adsorbent, and carries strontium chloride with high ammonia absorption capacity. The composite material adsorbent can allow a large number of ammonia molecules to pass through, fully react with strontium chloride, and store them in large quantities in the form of a complex.

[0051] like Figure 2 , Figure 3As shown, in this embodiment, an ammonia outlet pipe 202 is provided on the solid ammonia storage unit 1, and the solid ammonia storage unit 1 is composed of 4 identical reactors 204, each reactor 204 is composed of a shell and 7 identical unit tubes 301 tightly arranged in the shell, and a water pipe is passed through the unit tube 301. The water pipes in each unit tube 301 are connected in parallel to form a water circulation channel in the reactor, and the cavity between each unit tube 301 and the water pipe is filled with the strontium chloride-graphene aerogel composite material for adsorbing and storing ammonia.

[0052] In this embodiment, if Figure 3 As shown, the steps of filling the strontium chloride-graphene aerogel composite adsorbent are: injecting a mixed solution of strontium chloride and graphene into the cavity between each unit tube 301 and the water pipe, then introducing low-temperature liquid nitrogen into the unit tube 301 to make the mixed solution of strontium chloride and graphene freeze quickly, and ice crystals grow from the outer wall of the water pipe to the surrounding area. After the mixed solution is completely frozen, vacuum drying and thermal reduction are performed to finally form a layered structure strontium chloride-graphene aerogel composite adsorbent fin 302 filled in the water circulation channel.

[0053] In this embodiment, the mixed combustion and exhaust gas treatment cycle component also includes a third ammonia valve 7, a first ammonia nozzle 8, a turbocharger 9, an intercooler 10, a DOC unit 11, a DPF unit 12, a second ammonia nozzle 14, an oil pump 15, a fuel tank 16 and a third ammonia nozzle 17; the first ammonia nozzle 8 is connected to the solid ammonia storage unit 1 through a pipeline provided with a first ammonia valve 2, and a third ammonia valve 7 is arranged on the pipeline; the second ammonia nozzle 14 is connected to the solid ammonia storage unit 1 through a pipeline provided with a second ammonia valve 4; the turbocharger 9 is divided into two paths, one of which is connected to the third ammonia nozzle 17 through the intercooler 10, and the other is connected to the DOC unit 11, the DPF unit 12 and the SCR unit 13 in sequence, and the fuel tank 16 is connected to the oil pump 15 and the third ammonia nozzle 17 in sequence through a pipeline;

[0054] A part of the ammonia desorbed by the solid ammonia storage unit assembly is sprayed out through the first ammonia nozzle 8, mixed with the exhaust gas to be treated and then enters the turbocharger 9, and a part of the pressurized gas is cooled by the intercooler 10 and then enters the third ammonia nozzle 17; the third ammonia nozzle 17 sprays each material into the engine 6 for mixed combustion, and the remaining ammonia desorbed by the solid ammonia storage unit assembly enters the second ammonia nozzle 14; another part of the gas pressurized by the turbocharger 9 is processed by the DOC unit 11 and the DPF unit 12 in turn, and then enters the SCR unit 13, and is processed in the SCR unit 13 together with the ammonia sprayed by the second ammonia nozzle 14.

[0055] In some specific embodiments, in the engine, the ammonia and diesel mixture undergoes a process of compression, combustion expansion and recompression to drive the normal operation of the engine, and the mixing energy ratio of ammonia and diesel injected into the engine 6 for combustion is 10% to 80%. In this embodiment, the mixing energy ratio of ammonia and diesel injected into the engine 6 for combustion is 30%, which can effectively reduce tail gas emissions without reducing combustion efficiency.

[0056] In this embodiment, the mixed combustion and exhaust gas treatment circulation component uses the ammonia desorbed from the solid ammonia storage unit 1 to treat the exhaust gas, which can effectively avoid system blockages that may be caused by crystallization of urea aqueous solution in a low temperature environment, while effectively reducing exhaust nitrogen oxide emissions, thereby improving the overall efficiency and reliability of the integrated system of the present invention.

[0057] In this embodiment, the high-temperature cylinder head water driven ammonia desorption working cycle component makes full use of the waste heat generated during the operation of the engine 6 to heat the cylinder head water; as the water temperature rises, the high-temperature cylinder head water enters the solid ammonia storage unit 1, accelerates the collision frequency between the ammonia molecules and the strontium chloride molecules in the strontium chloride-graphene aerogel composite material, promotes the breaking of the coordination bonds between the strontium chloride and the ammonia molecules, and desorbs the ammonia molecules from the adsorbent; after the desorption is completed, the cooled cylinder head water returns to the cylinder head of the engine 6 to continue to absorb the heat emitted by the engine 6.

[0058] The integrated system of this embodiment releases ammonia during the day and fills ammonia at night, including the following steps:

[0059] (a) Filling

[0060] Under standard atmospheric pressure, the critical temperature of ammonia desorption / adsorption of metal halides such as strontium chloride is 35.2° C. Taking advantage of the lower temperature at night, ammonia is charged into the solid ammonia storage unit 1 at a pressure of 1.0 MPa, so that the strontium chloride-graphene aerogel composite adsorbent fin 302 adsorbs and stores more ammonia, thereby reserving sufficient ammonia supply for daytime use needs;

[0061] (b) Desorption

[0062] During the day, when the engine 6 is running, high-temperature cylinder head water enters the solid ammonia storage unit 1, causing the strontium chloride-graphene aerogel composite adsorbent fins 302 to desorb ammonia, thereby effectively meeting the demand for ammonia in vehicle operation and exhaust gas treatment.

[0063] The working process of this embodiment is as follows:

[0064] Taking advantage of the lower temperature at night, ammonia is charged into the solid ammonia storage unit 1 at a pressure of 1.0 MPa, so that the strontium chloride-graphene aerogel composite adsorbent fins 302 adsorb and store more ammonia, thereby reserving sufficient ammonia supply for daytime use needs. During the day, when the engine is running, the waste heat generated during the operation of the engine 6 heats the cylinder head water. As the water temperature rises, the high-temperature cylinder head water enters the solid ammonia storage unit 1 through the cylinder head water inlet pipe 201, and transfers heat to the solid ammonia storage unit 1, causing the strontium chloride-graphene aerogel composite adsorbent fins 302 in the solid ammonia storage unit 1 to undergo a desorption reaction. The cylinder head water that has been cooled after heat exchange returns to the engine 6 through the cylinder head water outlet pipe 203. Part of the desorbed ammonia is sprayed out through the first ammonia nozzle 8, mixed with the exhaust gas to be treated and then enters the turbocharger 9. Part of the gas after supercharging is cooled by the intercooler 10 and enters the third ammonia nozzle 17; the third ammonia nozzle 17 sprays each material into the engine 6 for mixed combustion, and each material undergoes a process of compression, combustion expansion and recompression to promote the normal operation of the engine 6. The remaining ammonia desorbed by the solid ammonia storage unit assembly enters the second ammonia nozzle 14; another part of the gas after supercharging by the turbocharger 9 is processed by the DOC unit 11 and the DPF unit 12 in turn, and then enters the SCR unit 13, and is processed in the SCR unit 13 with the ammonia sprayed by the second ammonia nozzle 14. Under the action of the catalyst in the SCR unit 13, the ammonia and NOx undergo an oxidation-reduction reaction to generate N 2 and H 2 O, thereby achieving the purpose of eliminating NOx.

[0065] The simulated loading diagram of the integrated system of mixed combustion and tail gas treatment based on solid ammonia storage in this embodiment is as follows: Figure 4 Compared with the traditional muck truck, the vehicle is equipped with an identical solid ammonia storage unit 3001 on both sides, and each solid ammonia storage unit 3001 contains four identical reactors 204. This design is convenient for the replacement of the solid ammonia storage unit 3001 and for filling ammonia.

[0066] According to calculations, the system can store 24kg of ammonia. Taking the SAIC Hongyan Jiehu H6 muck truck as an example, with an average daily transportation distance of 300km, mixing ammonia with diesel at an energy ratio of 30% for combustion can save about 27L of fuel. This integrated system of mixed combustion and exhaust gas treatment based on solid ammonia storage not only reduces the dependence of medium and heavy trucks on petroleum energy, but also promotes the low-carbon transformation and development of medium and heavy trucks. In terms of environmental protection, every 1L of diesel consumed will produce 2.63kgCO 2 This mixed combustion method can reduce about 71kgCO emissions per day. 2 emission.

[0067] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A comprehensive system for mixed combustion and tail gas treatment based on solid ammonia storage, characterized in that: It includes a solid ammonia storage unit component, a high-temperature cylinder cover water-driven ammonia desorption working cycle component, and a mixed combustion and exhaust gas treatment cycle component; among which, The solid-state ammonia storage unit assembly comprises a solid-state ammonia storage unit (1), which uses a metal halide-graphene aerogel composite material as an adsorbent for adsorbing and storing ammonia; The high-temperature cylinder cover water-driven ammonia desorption working cycle assembly includes an engine (6); The mixed combustion and exhaust gas treatment cycle component includes an SCR unit (13); When the engine (6) is running, water in the engine cylinder cover enters the solid ammonia storage unit (1), causing the adsorbent to undergo a desorption reaction. Part of the desorbed ammonia is mixed with air and then enters the engine cylinder for mixed combustion. Another part of the ammonia is mixed with the exhaust gas to be treated and then enters the SCR unit (13). The ammonia undergoes an oxidation-reduction reaction with NOx to generate N2 and H2O, thereby eliminating NOx. At the same time, the flue gas waste heat generated by the vehicle during operation is used for ammonia desorption in the solid ammonia storage unit (1), thereby making full use of the flue gas waste heat resources.

2. The integrated system for mixed combustion and tail gas treatment based on solid ammonia storage according to claim 1, characterized in that: The solid-state ammonia storage unit assembly further comprises a first ammonia valve (2), a second ammonia valve (4), a first cylinder cover water valve (3) and a second cylinder cover water valve (5); The engine cylinder cover water is connected to two cylinder cover water pipelines, one of which is a cylinder cover water inlet pipe (201) on which a first cylinder cover water valve (3) is arranged, and the engine cylinder cover water enters the solid ammonia storage unit (1) through the cylinder cover water inlet pipe (201), and the other is a cylinder cover water outlet pipe (203) on which a second cylinder cover water valve (5) is arranged, and the engine cylinder cover water after heat exchange in the solid ammonia storage unit (1) returns to the engine (6) through the cylinder cover water outlet pipe (203); The solid ammonia storage unit (1) is connected to the SCR unit (13) via two pipelines, one pipeline being provided with a first ammonia valve (2) and the other pipeline being provided with a second ammonia valve (4).

3. The integrated system for mixed combustion and tail gas treatment based on solid ammonia storage according to claim 1, characterized in that: In the metal halide-graphene aerogel composite material, the mass ratio of metal halide to graphene aerogel is 1:1 to 5:

1.

4. The integrated system for mixed combustion and tail gas treatment based on solid ammonia storage according to claim 3 is characterized in that: The metal halide is selected from at least one of strontium chloride and calcium chloride.

5. A comprehensive system for mixed combustion and tail gas treatment based on solid ammonia storage according to claim 1 or 3, characterized in that: The solid-state ammonia storage unit (1) is composed of a plurality of reactors (204), each reactor (204) being composed of a shell and a plurality of unit tubes (301) closely arranged in the shell, a water pipe passing through the unit tube (301), the water pipes in each unit tube (301) being connected in parallel to form a water circulation channel in the reactor, and the cavity between each unit tube (301) and the water pipe is filled with the metal halide-graphene aerogel composite material for adsorbing and storing ammonia.

6. The integrated system for mixed combustion and tail gas treatment based on solid ammonia storage according to claim 5, characterized in that: The steps of filling the metal halide-graphene aerogel composite material are as follows: injecting a mixed liquid of metal halide and graphene into the cavity between each unit tube (301) and the water pipe, then introducing low-temperature liquid nitrogen into the unit tube (301) to freeze the mixed liquid of metal halide and graphene quickly, and allowing ice crystals to grow from the outer wall of the water pipe to the surrounding areas. After the mixed liquid is completely frozen, vacuum drying and thermal reduction are performed to finally form a layered composite material adsorbent fin filled in the water circulation channel.

7. The integrated system of mixed combustion and tail gas treatment based on solid ammonia storage according to claim 1, characterized in that: The mixed combustion and tail gas treatment circulation component also includes a third ammonia valve (7), a first ammonia nozzle (8), a turbocharger (9), an intercooler (10), a DOC unit (11), a DPF unit (12), a second ammonia nozzle (14), an oil pump (15), a fuel tank (16) and a third ammonia nozzle (17); The first ammonia nozzle (8) is connected to the solid ammonia storage unit (1) via a pipeline provided with a first ammonia valve (2), and a third ammonia valve (7) is arranged on the pipeline; The second ammonia nozzle (14) is connected to the solid ammonia storage unit (1) via a pipeline provided with a second ammonia valve (4); The turbocharger (9) is divided into two paths, one of which is connected to the third ammonia nozzle (17) through the intercooler (10), and the other is connected to the DOC unit (11), the DPF unit (12) and the SCR unit (13) in sequence. The oil tank (16) is connected to the oil pump (15) and the third ammonia nozzle (17) in sequence through pipelines; A portion of the ammonia gas desorbed by the solid ammonia storage unit assembly is sprayed out through the first ammonia nozzle (8), mixed with the tail gas to be treated and then enters the turbocharger (9), and a portion of the gas after supercharging is cooled by the intercooler (10) and then enters the third ammonia nozzle (17); the third ammonia nozzle (17) sprays the various materials into the engine (6) for mixed combustion, and the remaining ammonia gas desorbed by the solid ammonia storage unit assembly enters the second ammonia nozzle (14); Another part of the gas pressurized by the turbocharger (9) is processed in turn by the DOC unit (11) and the DPF unit (12), and then enters the SCR unit (13), where it is processed together with the ammonia injected by the second ammonia nozzle (14) in the SCR unit (13).

8. The integrated system for mixed combustion and tail gas treatment based on solid ammonia storage according to claim 7, characterized in that: The mixing energy ratio of ammonia and diesel injected into the engine (6) for combustion is 10% to 80%.

9. The integrated system for mixed combustion and tail gas treatment based on solid ammonia storage according to claim 1, characterized in that: The high-temperature cylinder head water driven ammonia desorption working cycle component fully utilizes the waste heat generated during the operation of the engine (6) to heat the cylinder head water; As the water temperature increases, the high-temperature cylinder cover water enters the solid ammonia storage unit (1), promoting the breaking of the coordination bonds between the metal halide and the ammonia molecules, so that the ammonia molecules are desorbed from the adsorbent; After the desorption is completed, the cooled cylinder cover water returns to the cylinder cover of the engine (6) and continues to absorb the heat emitted by the engine (6).

10. The integrated system of mixed combustion and tail gas treatment based on solid ammonia storage according to claim 1, characterized in that: The system releases ammonia during the day and fills it at night, including the following steps: (a) Filling At night, ammonia is charged into the solid ammonia storage unit (1) at a pressure of 0.5 MPa to 1.0 MPa, so that the adsorbent adsorbs and stores the ammonia; (b) Desorption During the day, when the engine (6) is running, high-temperature cylinder cover water enters the solid ammonia storage unit (1), causing the adsorbent to desorb ammonia.

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