A Brown cyclone flow composite anode plasma porous medium combustor

Abstract

A Brown cyclone flow composite anode plasma porous medium burner, belonging to the field of combustion technology, includes a grounded protection support housing. There are slots inside the grounded protection support housing. A ring-shaped bluff body anode and a columnar anode are arranged inside the grounded protection support housing. A Brown gas transportation channel communicating with the Brown gas inlet hole is reserved between the ring-shaped bluff body anode and the grounded protection support housing. A fuel transportation channel communicating with the fuel inlet is reserved between the ring-shaped bluff body anode and the columnar anode. The columnar anode is connected to a columnar anode power supply interface, and the ring-shaped bluff body anode is connected to a ring-shaped bluff body anode power supply interface. The present invention can achieve sufficient premixing before ignition, greatly improve the activation energy of reactants, have good stable combustion and super-enthalpy combustion effects.

Description

Technical Field

[0001] The present invention belongs to the field of combustion technology, and particularly relates to a Brown cyclone composite anode plasma porous medium burner. Background Art

[0002] To cope with the change of the global climate, environmental protection has become increasingly important. Hydrogen energy is considered to be one of the most promising energy sources. The utilization of hydrogen energy in a broad sense should include the utilization of hydrogen isotopes (deuterium, tritium), as well as free radicals and plasmas such as hydrogen ions and negative hydrogen ions, in addition to hydrogen gas. Therefore, based on the concept of broad hydrogen energy, there are still many potential hydrogen energy application characteristics and hydrogen energy application scenarios that have not been fully explored at the present stage. Among them, Brown gas, as a hydrogen-rich mixed gas, can play a role in gas-phase catalytic combustion during the combustion process. In recent years, it has been popularized in the fields of welding, medical treatment, and carbon reduction in automobiles, but there are few reports in the field of burner applications. Brown gas is colorless, odorless, and non-toxic, and can generally be obtained by electrolyzing alkaline solutions. The contents of H2 and O2 are strictly in an exact ratio of 2:1 (60.79% and 30.39%) to achieve the characteristics of safe combustion without explosion. In addition, Brown gas contains a large number of active free radicals such as -H, -OH, and -O, which can promote the cracking of high-carbon hydrogen chains in fuels, accelerate the oxidation reaction rate, and have the characteristics of flame temperature reduction and fast propagation speed. The only product is water, and no toxic or harmful substances are produced.

[0003] Existing plasma burners are mainly used for stabilizing the combustion of pulverized coal boilers at low loads. Although they are widely used in direct ignition of thermal power boilers due to their advantages such as oil-free and high efficiency, certain problems have also emerged in long-term applications: short equipment life, high power consumption, high activation energy requirements, low ionization energy utilization rate, single ionized gas phase medium, and poor fuel adaptability. Therefore, it is necessary to adopt advanced gas phase media and efficient stable gas dynamic structures, combined with the ladder electrode composite non-equilibrium plasma combustion assistance technology to increase the concentration and activity of activated particles, reduce the ionization limit, enhance the premixing effect, and achieve efficient and clean combustion of the burner. Summary of the Invention

[0004] Aiming at the problems existing in the prior art, the present invention provides a Brown cyclone composite anode plasma porous medium burner, which can achieve sufficient premixing before ignition, greatly improve the activation energy of reactants, and have good stable combustion and super-enthalpy combustion effects.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A Brown cyclone flow composite anode plasma porous medium burner, comprising a grounded protection support housing with slots inside. The slots are, in order from front to back, an annular bluff body anode placement slot area, a swirl mixing area, and a flame diffusion area. Between the swirl mixing area and the flame diffusion area is a grounded support housing discharge contraction section. Inside the space formed by the annular bluff body anode placement slot area, the swirl mixing area, and the grounded support housing discharge contraction section, an annular bluff body anode and a columnar anode are sequentially arranged from outside to inside. A Brown gas transport channel communicating with the Brown gas inlet orifice is reserved between the annular bluff body anode and the grounded protection support housing. A fuel transport channel communicating with the fuel inlet is reserved between the annular bluff body anode and the columnar anode. The ends of the Brown gas transport channel and the fuel transport channel communicate with each other and extend to the swirl mixing area and the flame diffusion area. The columnar anode is connected to a columnar anode power interface, and the annular bluff body anode is connected to an annular bluff body anode power interface. The annular bluff body anode is cylindrical, with a straight inner wall and an outwardly curved outer wall. The columnar anode includes a columnar anode support rod, a columnar anode swirl body, and a columnar anode discharge section connected in sequence. The columnar anode support rod is straight and is arranged inside the annular bluff body anode. The columnar anode swirl body is composed of several blades, and the columnar anode discharge section penetrates the columnar anode swirl body and is connected to the columnar anode support rod. The columnar anode swirl body communicates with the swirl mixing area.

[0007] Further, the outer side of the annular bluff body anode and the inner side of the grounded protection support housing together form an annular Laval nozzle flow channel, and the expansion outlet area of the annular Laval nozzle flow channel accounts for 50% to 60% of the diameter of the projected area of the columnar anode swirl body.

[0008] Further, the front end of the annular bluff body anode is provided with an annular bluff body anode positioning disk. The annular bluff body anode is connected to the grounded protection support housing through the annular bluff body anode positioning disk. The annular bluff body anode positioning disk is provided with Brown gas flow holes, inter-electrode fuel flow holes, and a positioning disk columnar anode opening. The Brown gas flow holes are located between the outer side wall of the annular bluff body anode and the grounded protection support housing. The inter-electrode fuel flow holes are located between the inner side wall of the annular bluff body anode and the columnar anode support rod. The columnar anode support rod is placed in the positioning disk columnar anode opening.

[0009] Further, the columnar anode swirl body has double-arc blades, which are spirally diverging around the center of the circle, and the number of blades is 5 to 6.

[0010] Further, the grounding protection support housing includes an integrally formed annular blunt body anode leading edge protection section, a dielectric barrier discharge section, and a burner support base. The annular blunt body anode leading edge protection section and the dielectric barrier discharge section are straight cylindrical structures with the same inner and outer diameters. One side of the annular blunt body anode leading edge protection section is provided with a Brown gas inlet hole. The front end of the burner support base is a straight cylindrical structure with an inner diameter the same as that of the dielectric barrier discharge section, and the rear end is a frustum-shaped structure with a decreasing inner diameter in the direction of the flame diffusion area. The rear end of the burner support base is connected to the dense phase part of the porous medium. A porous steel sleeve is sleeved outside the dense phase part of the porous medium. The inside of the dense phase part of the porous medium is a frustum-shaped structure with a decreasing inner diameter towards the grounding support housing discharge contraction section. An unloading porous medium sparse phase part is provided inside the dense phase part of the porous medium. The outside of the dielectric barrier discharge section is wrapped with a stable arc inductance coil.

[0011] Further, the burner support base is provided with a flange with an outer diameter larger than that of the dielectric barrier discharge section, and the flange is provided with burner installation threaded holes.

[0012] Further, the fillers in the dense phase part of the porous medium and the unloading porous medium sparse phase part are solid balls of the same material. The material of the solid balls is an inert material with high temperature resistance such as alumina, silicon carbide, and yttrium-based zirconia. The porosity of the dense phase part of the porous medium is 0.65, the diameter of the small balls is 1 cm, the porosity of the unloading porous medium sparse phase part is 0.85, and the diameter of the large balls is 1.5 - 2 cm. The dense phase part of the porous medium and the unloading porous medium sparse phase part are separated by a porous corundum cover, and the opening diameter of the porous corundum cover is smaller than the diameter of the small balls.

[0013] Further, the front end of the columnar anode is fastened to the grounding protection support housing through a sealing head. The sealing head is provided with a fuel dispersion hole. The fuel dispersion hole is a flared trumpet shape that gradually expands from the outside to the inside, and the horizontal included angle of the flare is 30 - 45°. A ring-shaped branch flow channel parallel to the orifice wall is provided inside.

[0014] Further, the power supply for the annular blunt body anode is 0.5 - 10,000 volts; the material of the columnar anode is stainless steel or red copper, and the power supply is 1.5 - 20,000 volts.

[0015] Further, the inner core of the annular blunt body anode is an annular blunt body anode core. An annular blunt body anode inner insulation layer and an annular blunt body anode outer insulation layer are respectively provided on the inner side and the outer side of the annular blunt body anode core. The insulation layer material is quartz glass or ceramic, and the thickness is 2 - 4 mm. The material of the annular blunt body anode core is stainless steel or red copper. The annular blunt body anode outer insulation layer and the dielectric barrier discharge section form a front-end low-voltage discharge interval.

[0016] The advantages and beneficial effects of the present invention are:

[0017] The present invention uses Brown's gas as non-equilibrium plasma, which greatly reduces the ionization barrier and increases the concentration of activated free radicals. A composite anode is adopted. On the one hand, in the low-voltage discharge area at the front end, a low-voltage power supply method is used to ionize and activate Brown's gas. On the other hand, arc discharge occurs in the high-voltage discharge area at the back end to promote the catalytic combustion reaction of Brown's gas, realizing the stepped ionization of the composite anode and reducing the energy consumption of the burner. The Laval nozzle form is adopted in both the Brown's gas flow channel and the flame diffusion area to accelerate the flow velocity of Brown's gas and the flame diffusion velocity. A swirler is arranged in the high-voltage discharge area at the back end to enhance the premixing effect of non-equilibrium plasma and fuel, making the combustion more complete. In the flame diffusion area, a porous medium with a sparse / dense phase structure is adopted, which not only increases the combustion area and the radiation heat transfer area, improves the radiation heat transfer efficiency, realizes enthalpy combustion, but also has the characteristics of flexible start-stop and stable combustion. The Brown's gas cyclone composite anode plasma porous medium burner of the present invention can be used in pulverized coal / biomass boilers, waste incinerators, and stably burn boilers at low loads. Brief Description of the Drawings

[0018] Figure 1 It is a schematic structural diagram of a Brown's gas cyclone composite anode plasma porous medium burner of the present invention;

[0019] Figure 2 It is a schematic structural diagram of the burner sealing head;

[0020] Figure 3 It is a schematic structural diagram of the burner grounding protection support housing;

[0021] Figure 4 It is a schematic structural diagram of the burner annular blunt body anode and positioning disc;

[0022] Figure 5 It is a schematic structural diagram of the burner columnar anode and swirler;

[0023] Figure 6 For Figure 1 It is a schematic front-end face structure diagram of the positioning disc of the burner annular blunt body anode shown in the A-A cross-sectional view of

[0024] Figure 7 For Figure 1 It is a schematic cross-sectional structure diagram of the columnar anode swirler shown in the B-B cross-sectional view of

[0025] Figure 8 It is a schematic diagram of the fuel and Brown's gas flow process, and schematic diagrams of the front low-voltage discharge area and the back high-voltage discharge area.

[0026] In the figure: 1 - Fastening screw for the insulating rear end cover of the sealing head; 2 - Arc-stabilizing inductor coil; 3 - Ground protection support housing; 4 - Columnar anode; 5 - Threaded hole for burner installation; 6 - Dense-phase part of porous medium; 7 - Power supply interface for columnar anode; 8 - Sealing head; 9 - Fixed bolt for the positioning disc of the annular blunt-body anode; 10 - Front low-voltage discharge area; 11 - Annular blunt-body anode; 12 - Rear high-voltage discharge area; 13 - Porous steel sleeve; 14 - Loading and unloading sparse-phase part of porous medium; 15 - Porous corundum cover; 8-1 - Opening for columnar anode on the sealing head; 8-2 - Front insulating cover of the sealing head; 8-3 - Fuel diffusing orifice; 8-4 - Fuel inlet; 8-5 - Power supply interface for annular blunt-body anode; 8-6 - Rear insulating cover of the sealing head; 8-7 - Threaded hole for installing the rear insulating cover of the sealing head; 3-1 - Front-edge protection section of the annular blunt-body anode; 3-2 - Slot area for placing the annular blunt-body anode; 3-3 - Burner support seat; 3-4 - Swirl mixing area; 3-5 - Gas inlet orifice for Brown gas; 3-6 - Dielectric barrier discharge section; 3-7 - Discharge section of the ground support housing; 3-8 - Discharge contraction section of the ground support housing; 3-9 - Flame diffusion area; 11-1 - Opening for columnar anode on the positioning disc; 11-2 - Front edge of the annular blunt-body anode; 11-3 - Positioning disc of the annular blunt-body anode; 11-4 - Outer insulating layer of the annular blunt-body anode; 11-5 - Inner insulating layer of the annular blunt-body anode; 11-6 - Core body of the annular blunt-body anode; 11-7 - Inter-electrode fuel flow hole; 11-8 - Gas flow hole for Brown gas; 11-9 - Slot area for placing the columnar anode; 11-10 - Rear edge of the annular blunt-body anode; 4-1 - Support rod for columnar anode; 4-2 - Swirler for columnar anode; 4-3 - Discharge section of columnar anode. Detailed implementation manners

[0027] For better explanation of the present invention for easy understanding, the present invention will be described in detail below in conjunction with the accompanying drawings through specific implementation manners. Among them, the orientation terms such as "front" and "rear" mentioned in this article refer to Figure 1 the left side of Figure 1 is "front",

[0028] As Figure 1As shown in the figure, the present invention is a Brown cyclone flow composite anode plasma porous medium burner, which includes a grounded protection support housing 3. There are slots inside the grounded protection support housing 3. The slots are, in order from front to back, an annular bluff body anode placement slot area 3-2, a swirl mixing area 3-4, and a flame diffusion area 3-9. Between the swirl mixing area 3-4 and the flame diffusion area 3-9 is a grounded support housing discharge contraction section 3-8. The annular bluff body anode placement slot area 3-2 and the swirl mixing area 3-4 are straight cylindrical areas with the same inner diameter. The grounded support housing discharge contraction section 3-8 is a frustum-shaped structure with the same inner diameter as the swirl mixing area 3-4 at the front end and a decreasing inner diameter towards the back. The rear end of the grounded support housing discharge contraction section 3-8 is the flame diffusion area 3-9, and the flame diffusion area 3-9 is a frustum-shaped structure with the same inner diameter as the rear end of the grounded support housing discharge contraction section 3-8 at the front end and an increasing inner diameter towards the back.

[0029] In the space formed by the three parts of the annular bluff body anode placement slot area 3-2, the swirl mixing area 3-4, and the grounded support housing discharge contraction section 3-8, an annular bluff body anode 11 and a columnar anode 4 are arranged in sequence from outside to inside. A Brown gas transportation channel communicating with the Brown gas inlet hole 3-5 is reserved between the annular bluff body anode 11 and the grounded protection support housing 3. A fuel transportation channel communicating with the fuel inlet 8-4 is reserved between the annular bluff body anode 11 and the columnar anode 4. The ends of the Brown gas transportation channel and the fuel transportation channel are interconnected and extend to the swirl mixing area 3-4 and the flame diffusion area 3-9. As Figure 4 shown, the annular bluff body anode 11 is cylindrical, with a straight inner wall structure and an outwardly curved outer wall. The front end of the annular bluff body anode 11 is provided with an annular bluff body positioning disc 11-3. The annular bluff body anode 11 is connected to the grounded protection support housing 3 and the annular bluff body positioning disc fixing bolts 9 through the annular bluff body positioning disc 11-3. As Figure 6As shown, the annular blunt body anode positioning disc 11-3 is provided with a Brown gas flow hole 11-8, an inter-electrode fuel flow hole 11-7, and a positioning disc columnar anode opening 11-1. The Brown gas flow hole 11-8 is located between the outer side wall of the annular blunt body anode 11 and the grounding protection support housing 3. The inter-electrode fuel flow hole 11-7 is located between the inner side wall of the annular blunt body anode 11 and the columnar anode support rod 4-1. The columnar anode support rod 4-1 is placed in the positioning disc columnar anode opening 11-1 and is fixed in the columnar anode placement slot area 11-9 by means of screw threading. An interference fit is used between the annular blunt body anode 11 and the annular blunt body anode positioning disc 11-3. Around the positioning disc columnar anode opening 11-1, there are ≥4 inter-electrode fuel flow holes 11-7, and around the leading edge 11-2 of the annular blunt body anode, there are ≥12 Brown gas flow holes 11-8. In this way, a circular Brown gas transport channel is formed by the Brown gas inlet hole 3-5, the Brown gas flow hole 11-8, the outer side of the annular blunt body anode 11, and the inner side of the grounding protection support housing 3, and a circular fuel transport channel is formed by the sealing head 8, the inner side of the annular blunt body anode 11, and the outer side of the columnar anode support rod 4-1. Finally, the split transport of fuel and Brown gas before mixing is realized.

[0030] The profile of the outer side of the annular blunt body anode 11 is designed according to the Witoszynski formula. In this way, a circular Laval nozzle flow channel is formed by the outer side of the annular blunt body anode 11 and the inner side of the grounding protection support housing 3. On the one hand, the Brown gas is gradually accelerated after flowing through this flow channel from the Brown gas flow hole 11-8 and obtains greater kinetic energy before entering the swirl mixing area 3-4. On the other hand, the Brown gas accelerating past the outer side of the annular blunt body anode 11 can cool the annular blunt body anode 11. In addition, the expansion outlet area of the circular Laval nozzle flow channel accounts for 50% to 60% of the diameter of the projected area of the columnar anode swirl body 4-2 to ensure sufficient gas distribution of fuel and Brown gas.

[0031] The annular blunt body anode core 11-6 is wrapped by an insulating layer, which are respectively the annular blunt body anode inner insulating layer 11-5 and the annular blunt body anode outer insulating layer 11-4. The insulating layer material is quartz glass or ceramic, with a thickness of 2 to 4 mm. The annular blunt body anode core material is stainless steel or red copper. The annular blunt body anode outer insulating layer 11-4 and the dielectric barrier discharge section 3-6 form a front-end low-voltage discharge interval 10.

[0032] The columnar anode 4 is connected to the columnar anode power interface 7, and the annular blunt body anode 11 is connected to the annular blunt body anode power interface 8-5. As Figure 5As shown in the figure, the columnar anode 4 has a thinner front diameter and a thicker rear diameter, and can be divided into two parts. The front part with a thinner diameter is the columnar anode support rod 4-1, on which a columnar anode power supply interface 7 is connected. The rear part with a thicker diameter is the columnar anode discharge section 4-3, on which a columnar anode swirl body 4-2 is fastened. The columnar anode swirl body 4-2 is located in the swirl mixing zone 3-4. The columnar anode 4 is fastened to the ground protection support housing 3 through the columnar anode opening 8-1 on the sealing head 8. And on the rear insulating cover 8-6 of the sealing head, there is a ring-shaped blunt body anode power supply interface 8-5 connected to the ring-shaped blunt body anode 11. The columnar anode 4 includes a columnar anode support rod 4-1, a columnar anode swirl body 4-2, and a columnar anode discharge section 4-3 connected in sequence. The columnar anode support rod 4-1 is in a straight rod shape and is arranged inside the ring-shaped blunt body anode 11. The columnar anode swirl body 4-2 is composed of several blades. The columnar anode discharge section 4-3 passes through the columnar anode swirl body 4-2 and is connected to the columnar anode support rod 4-1. The columnar anode swirl body 4-2 is communicated with the swirl mixing zone 3-4. As Figure 7 shown, the columnar anode swirl body 4-2 adopts double-arc blades, which are spirally diverging around the center of the circle. The blade profile is designed by a fourth-order Bezier curve, and the number of blades is 5 to 6, which can not only ensure sufficient swirl of Brown gas and fuel, but also ensure smooth flow of fuel.

[0033] As Figure 2 shown, the sealing head 8 and the front end of the ground protection support housing 3 are fixedly connected through the sealing head insulating rear end cover fastening screw 1. The front end of the sealing head 8 is the sealing head front insulating cover 8-2, on which there is a columnar anode opening 8-1 of the sealing head. The rear end of the sealing head 8 is the sealing head rear insulating cover 8-6, on which there is a sealing head rear insulating cover installation threaded hole 8-7 for installing the sealing head insulating rear end cover fastening screw 1. There is a ring-shaped blunt body anode power supply interface 8-5 on the sealing head rear insulating cover 8-6. On one side of the sealing head 8, there is a fuel diffusing orifice 8-3. The fuel diffusing orifice 8-3 is in a gradually expanding flared shape from the outside to the inside. The inner side of the fuel diffusing orifice 8-3 has an annular flow channel separated by two annular wall surfaces for flow distribution. The flare horizontal angle is 30 to 45°, and there is an annular branch flow channel parallel to the orifice wall surface inside to disperse the gaseous fuel or solid powder fuel sprayed from the fuel inlet 8-4.

[0034] As Figure 3As shown in the figure, the grounding protection support housing 3 includes an integrally formed annular blunt body anode leading edge protection section 3-1, a dielectric barrier discharge section 3-6, and a burner support base 3-3. The annular blunt body anode leading edge protection section 3-1 and the dielectric barrier discharge section 3-6 are straight cylindrical structures with the same inner and outer diameters. A Brown gas inlet hole 3-5 is provided on one side of the annular blunt body anode leading edge protection section 3-1. The front end of the burner support base 3-3 is a straight cylindrical structure with the same inner diameter as that of the dielectric barrier discharge section 3-6, and the rear end is a frustum-shaped structure with a decreasing inner diameter in the direction of the flame diffusion zone 3-9. The rear end of the burner support base 3-3 is connected to the dense-phase section 6 of the porous medium. A porous steel sleeve 13 is sleeved outside the dense-phase section 6 of the porous medium. The inside of the dense-phase section 6 of the porous medium is a frustum-shaped structure with an inner diameter decreasing towards the inner radial grounding support housing discharge contraction section 3-8. An unloading and loading porous medium sparse-phase section 14 is provided inside the dense-phase section 6 of the porous medium. The outside of the dielectric barrier discharge section 3-6 is wrapped with a stable arc inductance coil 2.

[0035] The burner support base 3-3 is provided with a flange having an outer diameter larger than that of the dielectric barrier discharge section 3-6, and burner installation threaded holes 5 are provided on the flange.

[0036] The fillers in the dense-phase section 6 of the porous medium and the unloading and loading porous medium sparse-phase section 14 are solid balls of the same material, generally made of high-temperature resistant inert materials such as alumina, silicon carbide, and yttrium-based zirconia. The porosity of the dense-phase section 6 of the porous medium is about 0.65, the diameter of the small balls is 1 cm, the porosity of the unloading and loading porous medium sparse-phase section 14 is about 0.85, and the diameter of the large balls is 1.5 - 2 cm. The dense-phase section 6 of the porous medium and the unloading and loading porous medium sparse-phase section 14 are demarcated by a porous corundum cover 15, and the opening diameter of the porous corundum plate cover 15 is smaller than the diameter of the small balls. The dense-phase section 6 of the porous medium can ensure good wall heat storage capacity, and the flame can burn outward through the dense-phase section 6 of the porous medium and the porous steel plate 13. The unloading and loading porous medium sparse-phase section 14 is wrapped, shaped by a steel mesh, and fixed to the porous corundum cover 15. The diameter of the mesh holes of the steel mesh is smaller than the diameter of the large balls. The unloading and loading porous medium sparse-phase section 14 needs to be removed when burning solid-phase particulate fuel, and at the same time, it meets the combustion of solid-phase particulate fuel and gaseous fuel. The porous medium can achieve super-enthalpy and lean-phase combustion, increase the combustion reaction temperature and the fuel burnout rate, and can achieve flexible start-stop and stable combustion characteristics.

[0037] Since the combustible gas Brown gas is ionized in the front-end low-voltage discharge zone 10, at the same flow rate, Brown gas itself is rich in active free radicals, has a small ionization barrier, and requires a low activation energy. Therefore, the power supply in the front-end low-voltage discharge zone 10 is generally controlled at 0.5 - 10,000 volts to reduce the power consumption of the burner power supply. After being ionized, Brown gas generates a large amount of non-equilibrium plasma such as -H, -OH, -O free radicals, and positively charged cations, which participate in the next step of mixing, ionization, and combustion with the fuel, and have a catalytic combustion effect on the fuel.

[0038] Since the front-end low-voltage discharge section 10 adopts a low-voltage power supply method, a stabilizing arc inductor coil 2 is wrapped outside the dielectric barrier discharge section 3-6 on the grounding protection support housing 3 to achieve stable Brown gas ionization effect and ensure that high-concentration and active non-equilibrium plasma enters the swirl mixing zone 3-4.

[0039] The columnar anode discharge section 4-3 with a thicker diameter at the rear end of the columnar anode 4, the grounding support housing discharge section 3-7, and the grounding support housing discharge contraction section 3-8 together constitute the rear-end high-voltage discharge section 12. The material of the columnar anode 4 is stainless steel or red copper, and the supply power is 15,000 - 20,000 volts. The rear-end high-voltage discharge section 12 and the front-end low-voltage discharge section 10 form the burner composite anode ionization function, reducing energy consumption.

[0040] The rear-end high-voltage discharge section 12 and the loading and unloading porous medium lean-phase section 14 together constitute a structure similar to a Laval nozzle with a contraction section and an expansion section, realizing the accelerated diffusion of the combustion flame.

[0041] As Figure 8 shown, Brown gas enters the annular Laval nozzle flow channel between the outside of the annular blunt-body anode 11 and the inside of the grounding protection support housing 3 from the Brown gas inlet hole 3-5. On the one hand, the Brown gas is gradually accelerated after flowing through this flow channel by the Brown gas through-flow hole 11-8 and obtains greater kinetic energy before entering the swirl mixing zone 3-4. On the other hand, the Brown gas accelerating past the outside of the annular blunt-body anode 11 can cool the annular blunt-body anode 11. The fuel enters between the annular blunt-body anode 11 and the columnar anode support rod 4-1 from the fuel diffuser hole 8-3, and then the Brown gas and the fuel pass through the columnar anode swirl body 4-2 together. The function of the columnar anode swirl body 4-2 is to enable the carrier gas (Brown gas) passing through the front-end low-voltage discharge section to be fully mixed with the fuel. The columnar anode discharge section 4-3, the grounding support housing discharge section 3-7, and the grounding support housing discharge contraction section 3-8 together constitute the rear-end high-voltage discharge section 12, where high-voltage arc discharge occurs to form a flame; the flame diffusion zone 3-9 forms a diffusion flame channel, and the loading and unloading porous medium lean-phase section 14 is installed inside.

[0042] The working principle of the present invention is as follows: The carrier gas with Brown's gas as the gas-phase working medium passes through the front low-voltage discharge interval formed by the outer insulating layer of the annular bluff-body anode and the dielectric barrier discharge section, and dielectric barrier discharge occurs. Since the outer side of the annular bluff-body anode and the inner side of the grounded protection support housing together form the annular Laval nozzle flow channel, the Brown's gas carrier gas rich in free radicals generates a non-equilibrium plasma composed of high-velocity free electrons and positively charged cations. The fuel enters through the fuel inlet, is shunted through the fuel diffuser port, and enters the interelectrode fuel flow holes inside the burner. Finally, the fuel and the Brown's gas carrier gas pass through the columnar anode swirler and are fully mixed and enter the rear high-voltage discharge interval. Under the action of high voltage, arc discharge occurs between the outer side of the columnar anode discharge section and the discharge section of the grounded support housing, and finally, a stepwise ionization of high and low discharge regions is formed. At the same time, the Laval nozzle-like structure composed of the rear high-voltage discharge interval, the discharge contraction section of the grounded support housing, and the multi-hole medium lean-phase part of the loading and unloading promotes the acceleration of the diffusion flame generated by the high-voltage arc discharge. The flame forms a lean and super-enthalpy combustion of the gaseous fuel after passing through the multi-hole medium lean-phase region.

[0043] Example 1: As Figures 1 to 7 shown, a Brown's gas cyclone composite anode plasma multi-hole medium burner includes a grounded protection support housing 3, a columnar anode 4, a sealing head 8, and an annular bluff-body anode 11; the front end of the grounded protection support housing 3 is provided with a Brown's gas inlet hole 3-5 and an annular bluff-body anode leading-edge protection section 3-1; Brown's gas enters the burner through the Brown's gas inlet hole 3-5 at a certain flow rate ratio of 0%, 1%, 2%, 3%, 4%, 5%, 6%.

[0044] There are slots inside the grounding protection support housing 3. The slot area can be divided into an annular blunt body anode placement slot area 3-2, a swirl mixing area 3-4, and a flame diffusion area 3-9 in the front-to-back order. Between the swirl mixing area 3-4 and the flame diffusion area 3-9 is the grounding support housing discharge contraction section 3-8. Inside the space formed by the three parts of the annular blunt body anode placement slot area 3-2, the swirl mixing area 3-4, and the grounding support housing discharge contraction section 3-8, an annular blunt body anode 11 and a columnar anode 4 are placed. The annular blunt body anode 11 is bolted to the grounding protection support housing 3 through the annular blunt body anode positioning disc fixing bolt 9 and the annular blunt body anode positioning disc 11-3. The columnar anode 4 is fixed in the columnar anode placement slot area 11-9 by screwing through the positioning disc columnar anode opening 11-1 at the center of the annular blunt body anode positioning disc 11-3. On the columnar anode support rod 4-1, there is a columnar anode power supply interface 7, and the high voltage power supply applied in the experiment is 15,000 volts. On the columnar anode discharge section 4-3, a columnar anode swirl body 4-2 is fastened. The columnar anode swirl body 4-2 is located in the swirl mixing area 3-4. The columnar anode 4 is fastened to the grounding protection support housing 3 through the sealing head columnar anode opening 8-1 on the sealing head 8, and on the insulating cover 8-6 at the rear end of the sealing head, there is an annular blunt body anode power supply interface 8-5. The porous medium dense phase part 6, the loading and unloading porous medium sparse phase part 14, and the porous corundum cover 15 together constitute the flame diffusion area 3-9, and the outside of it is wrapped with a porous steel sleeve 13.

[0045] The experimental gas fuel is biomass pyrolysis gas, which enters the burner through the fuel diffuser orifice 8-3.

[0046] An interference fit is adopted between the annular blunt body anode 11 and the annular blunt body anode positioning disc 11-3. Around the periphery of the positioning disc columnar anode opening 11-1, there are inter-electrode fuel flow holes 11-7 for diverting fuel gas. Around the periphery of the leading edge of the annular blunt body anode 11-2, there are Brown gas flow holes 11-8 for diverting Brown gas.

[0047] The annular blunt body anode core 11-6 is wrapped by insulating layers, namely the annular blunt body anode inner insulating layer 11-5 and the annular blunt body anode outer insulating layer 11-4. The annular blunt body anode outer insulating layer 11-4 and the dielectric barrier discharge section 3-6 form a front-end low-voltage discharge interval 10. The low voltage power supply applied in the experiment is 8,000 volts. The outside of the dielectric barrier discharge section 3-6 is wrapped with a stable arc inductance coil 2.

[0048] After the Brown gas and the fuel are fully mixed, arc discharge occurs in the rear-end high-voltage discharge interval 12 jointly formed by the outside of the columnar anode discharge section 4-3, the grounding support housing discharge section 3-7, and the grounding support housing discharge contraction section 3-8, and a diffusion flame is formed. The carbon conversion characteristics of the fuel combustion are shown in Table 1 below.

[0049] The phased sparse part 14 of the loading and unloading porous medium was not installed in the experiment.

[0050] Table 1 Combustion characteristics data of the burner

[0051]

[0052] Table 1 shows that Brown's gas can provide more active free radicals to participate in combustion as a carrier gas. In addition, the porous medium structure can form a super-enthalpy combustion effect, significantly increasing the combustion temperature, playing a catalytic combustion effect on tar and carbon black, improving the fuel combustion efficiency, and efficiently converting the above substances into combustible gas (representative substance CO). Therefore, as the addition of Brown's gas increases, the concentration of CO continuously increases.

[0053] Although the present invention has been described in detail above with general descriptions and specific embodiments, based on the present invention, some modifications or improvements can be made, which are obvious to those skilled in the art. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection required by the present invention.

[0054] Example 2: As Figures 1 to 7 shown, a Brown's gas cyclone composite anode plasma porous medium burner includes a grounded protection support housing 3, a columnar anode 4, a sealing head 8, and an annular bluff body anode 11; a Brown's gas inlet hole 3-5 and an annular bluff body anode leading edge protection section 3-1 are provided at the front end of the grounded protection support housing 3; Brown's gas enters the burner through the Brown's gas inlet hole 3-5 at a certain flow rate ratio of 0%, 1%, 3%, 5%.

[0055] There are slots inside the grounding protection support housing 3. The slot area can be divided into an annular blunt body anode placement slot area 3-2, a swirl mixing area 3-4, and a flame diffusion area 3-9 in the front-to-back order. Between the swirl mixing area 3-4 and the flame diffusion area 3-9 is the grounding support housing discharge contraction section 3-8. Inside the space formed by the three parts of the annular blunt body anode placement slot area 3-2, the swirl mixing area 3-4, and the grounding support housing discharge contraction section 3-8, an annular blunt body anode 11 and a columnar anode 4 are placed. The annular blunt body anode 11 is bolted to the grounding protection support housing 3 through the annular blunt body anode positioning disc fixing bolt 9 and the annular blunt body anode positioning disc 11-3. The columnar anode 4 is fixed in the columnar anode placement slot area 11-9 by means of screwing through the positioning disc columnar anode opening 11-1 in the center of the annular blunt body anode positioning disc 11-3. On the columnar anode support rod 4-1, there is a columnar anode power supply interface 7, and the high-voltage power supply applied in the experiment is 15,000 volts. On the columnar anode discharge section 4-3, a columnar anode swirl body 4-2 is fastened. The columnar anode swirl body 4-2 is located in the swirl mixing area 3-4. The columnar anode 4 is fastened to the grounding protection support housing 3 through the sealing head columnar anode opening 8-1 on the sealing head 8, and an annular blunt body anode power supply interface 8-5 is provided on the insulating cover 8-6 at the rear end of the sealing head. The porous medium dense phase part 6, the loading and unloading porous medium sparse phase part 14, and the porous corundum cover 15 together form the flame diffusion area 3-9, and the outside of it is wrapped with a porous steel sleeve 13.

[0056] The experimental gas fuel is biomass pyrolysis gas, which enters the burner through the fuel diffuser orifice 8-3.

[0057] An interference fit is adopted between the annular blunt body anode 11 and the annular blunt body anode positioning disc 11-3. An inter-electrode fuel flow hole 11-7 is provided on the periphery of the positioning disc columnar anode opening 11-1 for diverting fuel gas. A Brown gas flow hole 11-8 is provided on the periphery of the leading edge 11-2 of the annular blunt body anode for diverting Brown gas.

[0058] The annular blunt body anode core 11-6 is wrapped by insulating layers, namely the annular blunt body anode inner insulating layer 11-5 and the annular blunt body anode outer insulating layer 11-4. The annular blunt body anode outer insulating layer 11-4 and the dielectric barrier discharge section 3-6 form a front-end low-voltage discharge interval 10. The low-voltage power supply applied in the experiment is 8,000 volts. The outside of the dielectric barrier discharge section 3-6 is wrapped with a stable arc inductance coil 2.

[0059] After the Brown gas and the fuel are fully mixed, arc discharge occurs in the rear-end high-voltage discharge interval 12 jointly formed by the outside of the columnar anode discharge section 4-3, the grounding support housing discharge section 3-7, and the grounding support housing discharge contraction section 3-8, and a diffusion flame is formed. The tar residue effect of fuel combustion is shown in Table 2 below.

[0060] The dense phase part 6 of the porous medium and the loading and unloading porous medium dilute phase part 14 are demarcated by a porous corundum cover 15; the loading and unloading porous medium dilute phase part 14 is wrapped and shaped by a steel mesh and fixed to the porous corundum cover 15. In the experiment, the dilute phase region 14 of the porous medium is filled with alumina balls, with a porosity of about 0.85 and a diameter of 1.5 - 2 cm.

[0061] Table 2 Tar content in the alumina balls of the dilute phase part of the burner's loading and unloading porous medium after desorption

[0062]

[0063] The data in Table 2 shows that Brown gas, as a carrier gas, can provide more active free radicals to participate in combustion, has a catalytic combustion effect on tar, and can improve the fuel combustion efficiency. In addition, the porous medium structure can form a super-enthalpy combustion effect to further intensify the cracking of tar and harmful substances. Especially when used for burning biomass pyrolysis gas, since biomass pyrolysis gas is prone to produce tar (excessive tar is likely to cause corrosion, pollution, increase in carbon black, and deteriorate the combustion effect), the above data shows that the tar yield of the burner using Brown gas as a carrier gas to burn biomass pyrolysis gas gradually decreases with the increase in the concentration of added Brown gas.

[0064] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A Brown cyclone flow composite anode plasma porous medium burner, characterized in that: It includes a ground protection support housing (3). There are slots inside the ground protection support housing (3). The slots are, in order from front to back, an annular blunt body anode placement slot area (3-2), a swirl mixing area (3-4), and a flame propagation area (3-9). Between the swirl mixing area (3-4) and the flame propagation area (3-9) is a ground support housing discharge contraction section (3-8). Inside the space formed by the three parts of the annular blunt body anode placement slot area (3-2), the swirl mixing area (3-4), and the ground support housing discharge contraction section (3-8), an annular blunt body anode (11) and a columnar anode (4) are arranged from outside to inside in sequence. There is a Brown gas transportation channel reserved between the annular blunt body anode (11) and the ground protection support housing (3) that is connected to the Brown gas inlet hole (3-5). There is a fuel transportation channel reserved between the annular blunt body anode (11) and the columnar anode (4) that is connected to the fuel inlet (8-4). The ends of the Brown gas transportation channel and the fuel transportation channel are interconnected and extend to the swirl mixing area (3-4) and the flame propagation area (3-9). The columnar anode (4) is connected to a columnar anode power interface (7), and the annular blunt body anode (11) is connected to an annular blunt body anode power interface (8-5). The annular blunt body anode (11) is cylindrical, with a straight inner wall structure and an outwardly curved arc-shaped outer wall. The columnar anode (4) includes a columnar anode support rod (4-1), a columnar anode swirl body (4-2), and a columnar anode discharge section (4-3) connected in sequence. The columnar anode support rod (4-1) is straight and is arranged inside the annular blunt body anode (11). The columnar anode swirl body (4-2) is composed of several blades. The columnar anode discharge section (4-3) passes through the columnar anode swirl body (4-2) and is connected to the columnar anode support rod (4-1). The columnar anode swirl body (4-2) is connected to the swirl mixing area (3-4). A front-end low-voltage discharge interval (10) is formed between the outside of the annular blunt body anode (11) and the annular blunt body anode placement slot area (3-2). The outside of the columnar anode discharge section at the rear end of the columnar anode (4) and the swirl mixing area (3-4) and the ground support housing discharge contraction section (3-8) constitute a rear-end high-voltage discharge interval (12).

2. The Brown cyclone flow composite anode plasma porous medium burner according to claim 1, characterized in that: The outside of the annular blunt body anode (11) and the inside of the ground protection support housing (3) together form an annular Laval nozzle flow channel. The expansion outlet area of the annular Laval nozzle flow channel accounts for 50% to 60% of the diameter of the projected area of the columnar anode swirl body (4-2).

3. The Brown cyclone flow composite anode plasma porous medium burner according to claim 1, characterized in that: The front end of the annular blunt body anode (11) is provided with an annular blunt body anode positioning disc (11-3). The annular blunt body anode (11) is connected to the grounding protection support housing (3) through the annular blunt body anode positioning disc (11-3). The annular blunt body anode positioning disc (11-3) is provided with a Brown gas flow hole (11-8), an inter-electrode fuel flow hole (11-7), and a positioning disc columnar anode opening (11-1). The Brown gas flow hole (11-8) is located between the outer side wall of the annular blunt body anode (11) and the grounding protection support housing (3). The inter-electrode fuel flow hole (11-7) is located between the inner side wall of the annular blunt body anode (11) and the columnar anode support rod (4-1). The columnar anode support rod (4-1) is placed inside the positioning disc columnar anode opening (11-1).

4. A Brown cyclone flow composite anode plasma porous medium burner according to claim 1, characterized in that: The columnar anode swirler (4-2) has double-arc blades, which are spirally diverging around the center of the circle, and the number of blades is 5 to 6 pieces.

5. A Brown cyclone flow composite anode plasma porous medium burner according to claim 1, characterized in that: The grounding protection support housing (3) includes an integrally formed annular blunt body anode leading edge protection section (3-1), a dielectric barrier discharge section (3-6), and a burner support base (3-3). The annular blunt body anode leading edge protection section (3-1) and the dielectric barrier discharge section (3-6) are straight cylindrical structures with the same inner and outer diameters. One side of the annular blunt body anode leading edge protection section (3-1) is provided with a Brown gas inlet hole (3-5). The front end of the burner support base (3-3) is a straight cylindrical structure with the same inner diameter as the dielectric barrier discharge section (3-6), and the rear end is a frustum-shaped structure with a decreasing inner diameter in the direction of the flame diffusion area (3-9). The rear end of the burner support base (3-3) is connected to the dense phase part of the porous medium (6). The outside of the dense phase part of the porous medium (6) is sleeved with a porous steel sleeve (13). The inside of the dense phase part of the porous medium (6) is a frustum-shaped structure with a decreasing inner diameter towards the inner radial grounding support housing discharge contraction section (3-8). The inside of the dense phase part of the porous medium (6) is provided with a loading and unloading porous medium sparse phase part (14). The outside of the dielectric barrier discharge section (3-6) is wrapped with a stable arc inductance coil (2).

6. A Brown cyclone flow composite anode plasma porous medium combustor according to claim 5, characterized in that: The burner support base (3-3) is provided with a flange with an outer diameter larger than that of the dielectric barrier discharge section (3-6), and the flange is provided with burner installation threaded holes (5).

7. A Brown cyclone flow composite anode plasma porous medium burner according to claim 5, characterized in that: The fillers in the dense phase part of the porous medium (6) and the loading and unloading porous medium sparse phase part (14) are solid balls of the same material. The material of the solid balls is an inert material with high temperature resistance such as alumina, silicon carbide, and yttrium-based zirconia. The porosity of the dense phase part of the porous medium (6) is 0.65, the diameter of the small balls is 1 cm, the porosity of the loading and unloading porous medium sparse phase part (14) is 0.85, and the diameter of the large balls is 1.5 to 2 cm. The dense phase part of the porous medium (6) and the loading and unloading porous medium sparse phase part (14) are demarcated by a porous corundum cover (15), and the opening diameter of the porous corundum cover (15) is smaller than the diameter of the small balls.

8. A Brown cyclone flow composite anode plasma porous medium burner according to claim 1, characterized in that: The front end of the columnar anode (4) is fastened to the grounding protection support housing (3) through a sealing head (8). A fuel diffusion orifice (8-3) is provided on the sealing head (8). The fuel diffusion orifice (8-3) is in the shape of a flaring trumpet that expands from the outside to the inside, with a flare horizontal included angle of 30 to 45°. A ring-shaped branch flow channel parallel to the orifice wall surface is provided inside.

9. A Brown cyclone flow composite anode plasma porous medium burner according to claim 1, characterized in that: The power supply for the annular blunt body anode (11) is 0.5 to 10,000 volts; the columnar anode (4) is made of stainless steel or red copper, and the power supply is 1.5 to 20,000 volts.

10. A Brown cyclone flow composite anode plasma porous medium combustor according to claim 1 or 5, characterized in that: The inner core of the annular blunt body anode (11) is the annular blunt body anode core (11-6). An annular blunt body anode inner insulation layer (11-5) and an annular blunt body anode outer insulation layer (11-4) are respectively provided on the inner side and the outer side of the annular blunt body anode core (11-6). The insulation layer material is quartz glass or ceramic, with a thickness of 2 to 4 mm. The material of the annular blunt body anode core (11-6) is stainless steel or red copper. The annular blunt body anode outer insulation layer (11-4) and the dielectric barrier discharge section (3-6) form a front-end low-voltage discharge interval (10).

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