Spray gun structure for blending combustion of waste mash thick slurry in circulating fluidized bed boiler

Abstract

The utility model discloses a spray gun structure for blending combustion of thick waste mash slurry in a circulating fluidized bed boiler. The spray gun structure solves the problem of how to convert waste mash slurry sprayed into a hearth into atomized liquid drops easy to burn. The compressed air is used as a spraying main line in the spraying gun, and the pressurized waste mash thick slurry is used as an attached substance, so that the waste mash thick slurry is mixed with the compressed air in a spraying gun pipe; a circular swirling plate is arranged in the spray head, so that after mixed compressed air and thick slurry of waste mash slurry pass through a group of cylindrical through holes capable of generating swirling flow, the swirling flow is shrunk and atomized under the action of an inner cavity of a conical cover of the spray head and is sprayed into a hearth from a nozzle of a spray gun, and liquid drops of the atomized waste mash slurry are fully combusted; the pressure intensity of the compressed air is larger than the pressure intensity when the waste mash slurry is input into the spray gun, the effect of preventing high-temperature carbonization of the waste mash slurry in the nozzle is achieved while atomized liquid drops of the waste mash slurry are conveyed into the hearth, and the phenomenon that the nozzle is blocked is prevented.

Description

Technical Field

[0001] The present invention relates to a circulating fluidized bed boiler using lignin residue as fuel, and particularly to a spray gun structure for co-firing concentrated waste mash slurry when the circulating fluidized bed boiler burns lignin residue. Background Art

[0002] With the rapid development of biomass energy technology, the process of producing cellulose fuel ethanol from straw raw materials has become increasingly mature. The waste mash slurry generated after producing fuel ethanol from straw is a high-concentration organic wastewater, which has a pungent smell and corrosiveness. Once it enters natural water bodies, it will destroy the ecological balance of the water bodies, cause water quality deterioration, and pollute the surrounding environment. The existing technology is to press the waste mash slurry into lignin residue through a plate and frame filter, and then distill and concentrate the filtrate into a thick slurry of waste mash slurry. In order to treat the waste mash slurry generated from producing fuel ethanol from straw, boiler manufacturers have developed a circulating fluidized bed boiler using lignin residue as fuel. This kind of boiler uses lignin residue as fuel and is supplemented by co-firing concentrated waste mash slurry, realizing the combustion treatment of harmful substances. During the combustion process of the circulating fluidized bed using lignin residue as fuel, the concentrated waste mash slurry is sprayed into the burning furnace through a spray gun to further realize the co-firing of the concentrated waste mash slurry. Since the temperature in the furnace is as high as over 600 degrees Celsius and the concentration of the concentrated waste mash slurry is also relatively high, how to convert the waste mash slurry sprayed into the furnace into atomized droplets that are easy to burn, and how to overcome the defect that the nozzle is prone to carbonization at high temperatures and cause nozzle blockage has become a technical problem to be solved on site. Summary of the Invention

[0003] The present invention provides a spray gun structure for co-firing concentrated waste mash slurry in a circulating fluidized bed boiler, which solves the technical problems of how to convert the waste mash slurry sprayed into the furnace into atomized droplets that are easy to burn and how to overcome the defect that the nozzle is prone to carbonization at high temperatures and cause nozzle blockage.

[0004] The present invention solves the above technical problems through the following technical solutions:

[0005] Overall concept of the present invention: Aiming at the characteristics of high concentration of waste mash slurry co-fired in the boiler and high temperature in the furnace, the present invention abandons the traditional idea of injecting waste mash slurry into the furnace in the form of single-fluid crushed liquid state. Taking compressed air as the main injection line in the spray gun and adding pressurized thick waste mash slurry as an additional admixture, the thick waste mash slurry is mixed with compressed air in the spray gun barrel. A circular swirl plate is arranged in the nozzle head, and cylindrical through holes for generating swirl are arranged at equal intervals in the concentric circumferences of the circular swirl plate. A conical protrusion is arranged at the center of the circular swirl plate. After the mixed compressed air and thick waste mash slurry pass through a group of cylindrical through holes capable of generating swirl, a swirl is generated under the guidance of the conical protrusion. The swirl is contracted and atomized under the action of the inner cavity of the conical cover of the nozzle head and is sprayed out from the spray port of the spray gun into the furnace, enabling the droplets of the atomized waste mash slurry to burn fully. The pressure of the compressed air is greater than the pressure when the waste mash slurry is input into the spray gun. While transporting the droplets of the atomized waste mash slurry into the furnace, it also prevents the waste mash slurry from being carbonized at high temperature in the nozzle and avoids the occurrence of nozzle blockage phenomenon.

[0006] A spray gun structure for co-firing thick waste mash slurry in a circulating fluidized bed boiler, including a spray gun barrel. A mixing chamber pipe is connected to the right port of the spray gun barrel. A compressed air input pipe is connected to the right port of the mixing chamber pipe. A thick slurry input pipe is connected to the pipe wall of the mixing chamber pipe. The central axes of the spray gun barrel, the mixing chamber pipe, and the compressed air input pipe coincide. The central axis of the thick slurry input pipe forms a 90-degree angle with the central axis of the mixing chamber pipe. A nozzle head base sleeve is connected to the left port of the spray gun barrel. An external thread is provided on the outer vertical surface at the left end of the nozzle head base sleeve. A nozzle head conical cover is connected to the left end of the nozzle head base sleeve. An internal thread is provided on the inner side of the right port of the nozzle head conical cover. The internal thread is screwed with the external thread. A cylindrical spray port is provided at the left end of the nozzle head conical cover. Between the nozzle head conical cover and the nozzle head base sleeve, a nozzle inner atomization conical jacket and a cylindrical swirl spacer are arranged in sequence along the left-to-right direction. A conical protrusion is provided at the center of the left vertical surface of the cylindrical swirl spacer. On the concentric circumference of the cylindrical swirl spacer outside the conical protrusion, a group of cylindrical through holes are arranged at equal intervals. The central axes of each cylindrical through hole are all inclined in the clockwise direction and form a 45-degree angle with the central axis of the cylindrical swirl spacer in space. The central axes of each cylindrical through hole are all arranged on the same concentric circumference of the cylindrical swirl spacer outside the conical protrusion.

[0007] The nozzle inner atomization conical jacket and the cylindrical swirl spacer are movably pressed between the nozzle head conical cover and the nozzle head base sleeve. A cylindrical outlet is provided at the left end of the nozzle inner atomization conical jacket. The cylindrical outlet is movably sleeved in the cylindrical spray port. A flange is fixedly provided in the middle of the outer side wall of the spray gun barrel.

[0008] An annular liquid storage chamber is provided on the inner wall of the tube lumen of the mixing chamber tube. Liquid inlet cylindrical through holes are equidistantly arranged at equal angular intervals on a concentric circumference of the inner side wall of the annular liquid storage chamber. The central axis of the liquid inlet cylindrical through hole deviates from the central axis of the mixing chamber tube, and the central axes of the liquid inlet cylindrical through holes are all arranged obliquely in the clockwise direction.

[0009] The diameter of the spray gun barrel is 32 mm, and the thickness of the atomizing conical jacket in the nozzle is 7 - 11 mm.

[0010] The present invention realizes the two-fluid conical atomization of compressed air and thick slurry of waste mash. The liquid droplets sprayed into the furnace have small particle sizes, good atomization effects, and sufficient combustion of the liquid droplets. At the same time, the compressed air continuously purges the nozzle, overcoming the occurrence of nozzle blockage caused by carbonization of the slurry in the nozzle. Brief Description of the Drawings

[0011] Figure 1 is a schematic structural diagram of the present invention;

[0012] Figure 2 is a diagram showing the mating relationship of the nozzle conical cover 8, the nozzle base sleeve 6, the atomizing conical jacket 11 in the nozzle, and the cylindrical swirling spacer 12 of the present invention. Detailed Description of the Invention

[0013] The present invention will be described in detail below with reference to the accompanying drawings:

[0014] A spray gun structure for co-firing thick waste mash slurry in a circulating fluidized bed boiler, comprising a spray gun barrel 1. A mixing chamber pipe 2 is connected to the right port of the spray gun barrel 1. A compressed air input pipe 3 is connected to the right port of the mixing chamber pipe 2. A thick slurry input pipe 4 is connected to the pipe wall of the mixing chamber pipe 2. The central axes of the spray gun barrel 1, the mixing chamber pipe 2, and the compressed air input pipe 3 coincide. The central axis of the thick slurry input pipe 4 forms a 90-degree angle with the central axis of the mixing chamber pipe 2. A nozzle base sleeve 6 is connected to the left port of the spray gun barrel 1. An external thread 7 is provided on the outer vertical surface at the left end of the nozzle base sleeve 6. A nozzle conical cover 8 is connected to the left end of the nozzle base sleeve 6. An internal thread 9 is provided on the inner side of the right port of the nozzle conical cover 8. The internal thread 9 is screwed together with the external thread 7. A cylindrical nozzle 10 is provided at the left end of the nozzle conical cover 8. The nozzle conical cover 8 is screwed together with the nozzle base sleeve 6 through the internal thread 9. Between the nozzle conical cover 8 and the nozzle base sleeve 6, a nozzle internal atomizing conical jacket 11 and a cylindrical swirl pad 12 are sequentially arranged in the left-to-right direction. The nozzle internal atomizing conical jacket 11 and the cylindrical swirl pad 12 are movably arranged between the nozzle conical cover 8 and the nozzle base sleeve 6 and can be replaced. A conical protrusion 13 is provided at the center of the left vertical surface of the cylindrical swirl pad 12. A group of cylindrical through holes 14 are equidistantly arranged on the concentric circumference of the cylindrical swirl pad 12 outside the conical protrusion 13. The central axes of the cylindrical through holes 14 are all inclined in the clockwise direction and form a 45-degree angle with the central axis of the cylindrical swirl pad 12 in space. The central axes of the cylindrical through holes 14 are all arranged on the same concentric circumference of the cylindrical swirl pad 12 outside the conical protrusion 13. The thick waste mash slurry transported by compressed air in the spray gun barrel 1 generates a swirling fluid after passing through the group of cylindrical through holes 14, and is accelerated by contraction through the nozzle internal atomizing conical jacket 11 under the guidance of the conical protrusion 13 to achieve two-fluid conical atomization. Finally, it is sprayed into the furnace through the cylindrical nozzle 10 to enable the droplets to burn fully.

[0015] The nozzle internal atomizing conical jacket 11 and the cylindrical swirl pad 12 are movably crimped between the nozzle conical cover 8 and the nozzle base sleeve 6. A cylindrical outlet 15 is provided at the left end of the nozzle internal atomizing conical jacket 11. The cylindrical outlet 15 is movably sleeved in the cylindrical nozzle 10. A flange 5 is fixedly provided in the middle of the outer side wall of the spray gun barrel 1. The spray gun is connected and fixed to the secondary air duct of the boiler through the flange 5.

[0016] Compressed air enters the inner cavity of the mixing chamber tube 2 along the central axis direction of the spray gun barrel 1, that is, in the B direction; the concentrated waste mash slurry enters the annular liquid storage chamber 16 of the mixing chamber tube 2 along the central axis of the concentrated slurry input pipe 4, that is, in the A direction. An annular liquid storage chamber 16 is provided on the inner cavity side wall of the mixing chamber tube 2. Liquid inlet cylindrical through holes 17 are equidistantly arranged at equal angular intervals on a concentric circumference of the inner side wall of the annular liquid storage chamber 16. The central axis of the liquid inlet cylindrical through hole 17 deviates from the central axis of the mixing chamber tube 2, and the central axes of the liquid inlet cylindrical through holes 17 are all arranged obliquely in the clockwise direction. The pressurized concentrated waste mash slurry enters and fills the annular liquid storage chamber 16 through the concentrated slurry input pipe 4. Since the pressure in the annular liquid storage chamber 16 is less than the pressure in the mixing chamber tube 2, when the compressed air passes through the annular liquid storage chamber 16 at high speed, a negative pressure is generated on the liquid inlet cylindrical through holes 17 arranged at equal angular intervals on a concentric circumference of the inner side wall of the annular liquid storage chamber 16, sucking the concentrated waste mash slurry in the annular liquid storage chamber 16 into the inner cavity of the mixing chamber tube 2. Since the central axes of the liquid inlet cylindrical through holes 17 deviate from the central axis of the mixing chamber tube 2 and the central axes of the liquid inlet cylindrical through holes 17 are all arranged obliquely in the clockwise direction, the concentrated waste mash slurry entering the inner cavity of the mixing chamber tube 2 enters in a swirling flow form and is conveyed to the left side of the spray gun barrel 1 under the entrainment of the high-pressure gas. While mixing with the high-pressure gas, a preliminary swirling flow conveying prototype is formed. Then, it passes through a group of cylindrical through holes 14 on the cylindrical swirling flow spacer 12 to achieve accelerated swirling flow. Finally, after the contraction and acceleration of the atomizing conical jacket 11 in the nozzle, it is atomized and sprayed into the furnace through the cylindrical nozzle 10.

[0017] The diameter of the spray gun barrel 1 is 32 mm, and the thickness of the atomizing conical jacket 11 in the nozzle is 7 - 11 mm; by replacing the atomizing conical jacket 11 with different thicknesses in the nozzle, the size of the cylindrical nozzle 10 can be adjusted.

Claims

1. A spray gun structure for a circulating fluidized bed boiler for mixing and burning waste mash slurry, comprising a spray gun pipe (1), characterized in that: A mixing chamber tube (2) is connected to the right end of the spray gun tube (1), a compressed air input tube (3) is connected to the right end of the mixing chamber tube (2), and a concentrated slurry input tube (4) is connected to the tube wall of the mixing chamber tube (2). The central axis of the spray gun tube (1), the central axis of the mixing chamber tube (2) and the central axis of the compressed air input tube (3) are coincident, and the central axis of the concentrated slurry input tube (4) is at 90 degrees to the central axis of the mixing chamber tube (2); a nozzle base sleeve (6) is connected to the left end of the spray gun tube (1), an external thread (7) is provided on the outer vertical surface of the left end of the nozzle base sleeve (6), a nozzle cone cover (8) is connected to the left end of the nozzle base sleeve (6), an internal thread (9) is provided on the inner side of the right end of the nozzle cone cover (8), the internal thread (9) is screwed together with the external thread (7), and a nozzle cone cover (8) is provided at the left end of the nozzle cone cover (8). A cylindrical nozzle (10) is arranged; between the nozzle conical cover (8) and the nozzle base sleeve (6), from left to right, a nozzle inner atomizing conical jacket (11) and a cylindrical swirl pad (12) are arranged in sequence; a conical protrusion (13) is arranged at the center of the left vertical surface of the cylindrical swirl pad (12); and on the concentric circumference of the cylindrical swirl pad (12) outside the conical protrusion (13), a A group of cylindrical through holes (14) are provided, wherein the central axis of each cylindrical through hole (14) is inclined in a clockwise direction and forms a 45-degree angle with the central axis of the cylindrical swirl pad (12) in space, and the central axis of each cylindrical through hole (14) is arranged on the same concentric circle on the cylindrical swirl pad (12) outside the conical protrusion (13); and the pressure in the mixing cavity tube (2) is lower than the pressure in the compressed air input tube (3).

2. The spray gun structure for mixing and burning waste mash slurry in a circulating fluidized bed boiler according to claim 1 is characterized in that: The atomizing cone jacket (11) and the cylindrical swirl pad (12) in the nozzle are movably crimped between the nozzle cone cover (8) and the nozzle base sleeve (6); a cylindrical outlet (15) is arranged at the left end of the atomizing cone jacket (11) in the nozzle, and the cylindrical outlet (15) is movably sleeved in the cylindrical nozzle (10); a flange (5) is fixedly arranged in the middle of the outer wall of the spray gun tube (1).

3. The spray gun structure for the circulating fluidized bed boiler for mixing and burning waste mash slurry according to claim 1 or 2, characterized in that: An annular liquid storage chamber (16) is provided on the inner wall of the mixing chamber (2), and liquid inlet cylindrical through holes (17) are provided at equal intervals on a concentric circle on the inner wall of the annular liquid storage chamber (16), the central axis of the liquid inlet cylindrical through hole (17) deviates from the central axis of the mixing chamber (2), and the central axis of the liquid inlet cylindrical through hole (17) is arranged to be inclined in a clockwise direction; the concentrated slurry input pipe (4) is connected to the annular liquid storage chamber (16).

4. The spray gun structure for the circulating fluidized bed boiler for burning waste mash slurry as claimed in claim 3 is characterized in that: The diameter of the spray gun tube (1) is 32 mm, and the thickness of the atomizing cone jacket (11) in the nozzle is 7-11 mm.

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