Pre-combustion device of ammonia-coal mixed combustion furnace

Abstract

The invention provides an ammonia-coal mixed combustion furnace pre-combustion device which comprises a preheating mechanism, the preheating mechanism is installed on one side of a hearth, and a separation mechanism used for accelerating impurity removal of high-temperature flue gas in the hearth is installed at one end of the preheating mechanism; a feeding sleeve used for conveying pulverized coal, ammonia gas and oxygen is installed in the middle of the interior of the preheating mechanism, the feeding sleeve communicates with a heat exchange mechanism used for rapidly preheating part of the ammonia gas and oxygen, and the heat exchange mechanism is located in the preheating mechanism. A plurality of turbulent flow mechanisms for improving the heat exchange effect are mounted on the side wall of the heat exchange mechanism; one end of the heat exchange mechanism is provided with an ignition mechanism for rapidly igniting the preheated ammonia gas, and one end of the ignition mechanism is provided with a mixing mechanism for uniformly mixing flame, the ammonia gas, pulverized coal and oxygen. The pre-combustion device of the ammonia-coal mixed combustion furnace provided by the invention has the advantages of quickly and uniformly combusting ammonia gas and improving the combustion efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of ammonia-coal mixed combustion, and in particular to a pre-combustion device of an ammonia-coal mixed combustion furnace. Background Art

[0002] As global awareness of environmental protection increases, reducing carbon dioxide emissions from coal-fired power generation has become key. Ammonia, as a potential low-carbon fuel, has attracted much attention due to its high volume energy density, low unit energy storage cost, and mature and complete large-scale storage and transportation technology. Ammonia-coal co-firing technology is a technology that combines ammonia and coal as a mixed fuel for combustion. Its core principle is to use ammonia as a carbon-free fuel and burn it together with coal to achieve the goals of low emissions and high efficiency.

[0003] The ignition temperature of ammonia is relatively high, and the flammability limit range of ammonia is narrow, the laminar flame propagation speed is low, and there are problems of difficulty in ignition and unstable combustion. In the prior art, coal powder is first ignited and then used as an ignition source for ammonia combustion. In order to make the coal powder a stable ignition source, the coal powder is generally subjected to a self-sustaining preheating combustion treatment, which easily results in a poor ammonia-oxygen coal mixing effect, which is not conducive to ammonia combustion, and the coal powder pretreatment increases the combustion steps and production costs.

[0004] Therefore, it is necessary to provide a new ammonia-coal mixed combustion furnace pre-combustion device to solve the above problems. Summary of the invention

[0005] The technical problem solved by the present invention is to provide a pre-combustion device for an ammonia-coal mixed combustion furnace which can make ammonia burn quickly and evenly and improve combustion efficiency.

[0006] In order to solve the above technical problems, the pre-combustion device of the ammonia-coal mixed combustion furnace provided by the present invention comprises: a preheating mechanism, the preheating mechanism is installed on one side of the furnace, and a separation mechanism for increasing the speed and removing impurities of the high-temperature flue gas inside the furnace is installed at one end of the preheating mechanism; a feeding sleeve for conveying coal powder, ammonia and oxygen is installed in the center of the preheating mechanism, and the feeding sleeve is connected to a heat exchange mechanism for quickly preheating part of the ammonia and oxygen, the heat exchange mechanism is located inside the preheating mechanism, and a plurality of turbulent mechanisms for improving the heat exchange effect are installed on the side wall of the heat exchange mechanism; an ignition mechanism for quickly igniting the preheated ammonia at one end of the heat exchange mechanism, and a mixing mechanism for evenly mixing the flame, ammonia, coal powder and oxygen at one end of the ignition mechanism; The preheating mechanism includes a preheating tube, the preheating tube is on one side of the furnace, and the separation mechanism is installed tangentially to the side wall of the preheating tube; one side of the preheating tube is fixedly connected to a partition, and a plurality of first nozzles and second nozzles are installed on the side wall of the partition, one end of the second nozzle is fixedly connected to an air inlet joint with an arc shape on the side wall, and one end of the air inlet joint arranged obliquely is in a funnel-shaped structure; the heat exchange mechanism includes a storage pipe, the other end of the preheating tube is installed with a storage pipe, and the storage pipe with a funnel shape inside is connected to the feed sleeve; a plurality of spiral heat exchange tubes are installed at one end of the storage pipe, and the heat exchange tube is composed of a plurality of first nozzles arranged obliquely on the side wall and in a semi-annular shape. The heat exchanger is composed of a connecting pipe, a second connecting pipe and a communicating pipe, the inner diameter of the first connecting pipe is smaller than the inner diameter of the second connecting pipe, and the adjacent first connecting pipes and the second connecting pipes are connected through the communicating pipe; the spoiler mechanism includes a fixed shaft, and a plurality of fixed shafts and a mounting pipe are installed in the center of the side wall of the heat exchange tube, and the side where the mounting pipe is connected to the heat exchange tube is in a truncated cone structure; the side walls of the fixed shaft are respectively installed with fan blades, eccentric blocks and twisted iron, the interior of the mounting pipe is rotatably connected to the eccentric block and the fixed shaft, and the interior of the heat exchange tube is installed with a plurality of twisted irons rotatably connected, and a sealing ring is installed at the connection between the fixed shaft and the heat exchange tube.

[0007] Preferably, the separation mechanism includes a booster cylinder, a booster cylinder is provided on one side of the furnace, the interior of the booster cylinder is rotatably connected to a turbine, and a motor for driving the turbine to rotate is installed on the surface of the booster cylinder; the side wall of the booster cylinder is connected to a cyclone separator, and an exhaust pipe is installed in the center of the side wall of the cyclone separator.

[0008] Preferably, a smoke exhaust pipe is installed on the surface of the furnace, and the smoke exhaust pipe is connected to the center of the bottom surface of the booster cylinder.

[0009] Preferably, the exhaust pipe is tangentially connected to the preheating tube, the first nozzle having a funnel-shaped end is obliquely arranged on the surface of the partition, and the air outlet of the first nozzle and the air inlet of the air inlet joint are facing the edge of the preheating tube.

[0010] Preferably, the feed sleeve is formed by a plurality of air inlet pipes and coal powder pipes, the air inlet pipes and the coal powder pipes are alternately arranged in sequence, and the outermost air inlet pipe is connected to the storage pipe.

[0011] Preferably, the ignition mechanism includes a second ignition tube, the second ignition tube is fixed to the side wall of the preheating tube, and the interior of the second ignition tube is connected to the pulverized coal pipe and the other air inlet pipes.

[0012] Preferably, the ignition mechanism also includes a first ignition tube, which is fixedly connected to the center of the interior of the partition, and an igniter is installed inside the first ignition tube; a funnel-shaped air inlet pipe is installed on the side wall of the heat exchange tube, and the air inlet pipe is inclined and tangent to the interior of the first ignition tube.

[0013] Preferably, the mixing mechanism includes a clamping ring, which is rotatably connected to the inside of the feed sleeve outlet, and the clamping ring with a circular cross-section is fixedly connected to a fixed ring; a plurality of protrusions are obliquely installed on the side wall of the fixed ring, and the protrusions are located at the outlet of the first ignition tube; the side wall of the fixed ring is fixedly connected to a spiral mixing ring, and the diameter of the mixing ring gradually decreases toward the outlet of the second ignition tube.

[0014] Preferably, the interiors of the first ignition tube and the second ignition tube are both funnel-shaped structures, and the interior of the second ignition tube is rotatably connected to the mixing ring.

[0015] Compared with the related art, the pre-combustion device of the ammonia-coal mixed combustion furnace provided by the present invention has the following beneficial effects: The present invention provides a pre-combustion device for an ammonia-coal mixed combustion furnace. When an airflow formed by a mixture of ammonia and oxygen enters the interior of the storage tube, a plurality of spiral heat exchange tubes are installed at one end of the storage tube, and the airflow is diverted into the interior of the plurality of heat exchange tubes, thereby accelerating the heat exchange efficiency of the airflow in the preheating tube. The inner diameter of the heat exchange tube is much smaller than the inner diameter of the storage tube, thereby increasing the flow velocity of the airflow in the heat exchange tube, causing the airflow to rotate and flow rapidly along the heat exchange tube, and forming turbulence in the airflow inside the heat exchange tube, thereby further improving the heat exchange efficiency. At the same time, the dust-removed flue gas is ejected through the second nozzle, and the center of the second nozzle is aligned with the center of the interior of the heat exchange tube. The flue gas ejected from the second nozzle flows rapidly in the interior of the heat exchange tube. According to the Bernoulli principle, the flue gas flowing rapidly in the center of the second nozzle generates suction, causing the flue gas at the inner edge of the preheating tube to move toward the direction of the heat exchange tube (as shown in the attached figure). Figure 3As shown), the flow rate of the gas around the heat exchange tube is increased, so that more high-temperature flue gas contacts the side wall of the heat exchange tube, and the flue gas directly impacts the surface of the heat exchange tube, thereby improving the convective heat transfer coefficient; in the process of the airflow flowing in the center of the heat exchange tube, the flue gas drives the fan blades, the fixed shaft, the eccentric block, and the twisted iron to rotate, and the twisted iron rotates inside the heat exchange tube, thereby enhancing the airflow disturbance inside the heat exchange tube and destroying the flow boundary layer inside the heat exchange tube to increase the heat transfer. At the same time, the movement direction of the airflow generated by the rotation of the fan blades is different from the flow direction of the flue gas, thereby disturbing the gas flowing at the center of the heat exchange tube, thereby further improving the heat exchange efficiency between the flue gas and the gas inside the heat exchange tube; in the process of the rotation of the fixed shaft, the eccentric block is driven in the The mounting tube rotates rapidly, and the centrifugal force generated by the rotation of the eccentric block obtains an exciting force, which is transmitted to the mounting tube and the heat exchange tube through the fixed shaft, so that the elastic heat exchange tube vibrates slightly inside the preheating tube, which is convenient for removing smoke adsorbed on the surface of the heat exchange tube, avoiding the adsorption of a large amount of smoke inside the heat exchange tube to affect the heat exchange efficiency, and the vibration of the heat exchange tube constantly disturbs the flow boundary layer of the gas, further improving the heat exchange efficiency and increasing the temperature of the gas inside the heat exchange tube; the high-temperature flue gas is used to quickly heat part of the oxygen and ammonia to increase the temperature of ammonia and oxygen, thereby facilitating the rapid ignition of this part of ammonia inside the ignition mechanism, and the ignited ammonia is used to ignite other ammonia and pulverized coal in the ignition mechanism, thereby improving the combustion effect of the fuel, and there is no need. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic structural diagram of a preferred embodiment of the pre-combustion device for the ammonia-coal mixed combustion furnace provided by the present invention; Figure 2 for Figure 1 An enlarged schematic diagram of the structure at A shown; Figure 3 for Figure 2 Schematic diagram of air flow around the heat exchange tube shown; Figure 4 for Figure 2 An enlarged schematic diagram of the structure at B shown; Figure 5 for Figure 2 A side view of the air intake connector structure is shown; Figure 6 for Figure 5 A top view of the air intake connector structure shown; Figure 7 for Figure 2 A side view of the heat exchange tube structure shown; Figure 8 for Figure 7 An enlarged schematic diagram of the structure at position C is shown; Fig. 9 for Figure 2 Side view of the hybrid ring structure shown.

[0017] Numbers in the figure: 1, furnace, 11, smoke exhaust pipe, 2, separation mechanism, 21, motor, 22, booster cylinder, 23, turbine, 24, cyclone separator, 25, exhaust pipe, 3, feed sleeve, 31, air intake pipe, 32, pulverized coal pipe, 4, preheating mechanism, 41, preheating cylinder, 42, partition, 43, first nozzle, 44, second nozzle, 45, air intake joint, 5, heat exchange mechanism, 51, storage pipe, 52, heat exchange pipe, 521, The first connecting pipe, 522, the second connecting pipe, 523, the connecting pipe, 53, the air inlet pipe, 6, the spoiler mechanism, 61, the fan blade, 62, the mounting pipe, 63, the fixed shaft, 64, the eccentric block, 65, the twisted iron, 66, the sealing ring, 7, the ignition mechanism, 71, the igniter, 72, the first ignition tube, 73, the second ignition tube, 8, the mixing mechanism, 81, the mixing ring, 82, the fixing ring, 83, the bump, 84, the retaining ring, 9, the smoke pipe. DETAILED DESCRIPTION

[0018] The present invention will be further described below in conjunction with the accompanying drawings and implementation modes.

[0019] See also Figures 1 to 9 , Figure 1 A schematic structural diagram of a preferred embodiment of the pre-combustion device for the ammonia-coal mixed combustion furnace provided by the present invention; Figure 2 for Figure 1 An enlarged schematic diagram of the structure at A shown; Figure 3 for Figure 2 Schematic diagram of air flow around the heat exchange tube shown; Figure 4 for Figure 2 An enlarged schematic diagram of the structure at B shown; Figure 5 for Figure 2 A side view of the air intake connector structure is shown; Figure 6 for Figure 5 A top view of the air intake joint structure shown; Figure 7 for Figure 2 A side view of the heat exchange tube structure shown; Figure 8 for Figure 7 An enlarged schematic diagram of the structure at position C is shown; Fig. 9 for Figure 2The side view of the mixing ring structure is shown. The pre-combustion device of the ammonia-coal mixed combustion furnace includes: a preheating mechanism 4, which is installed on one side of the furnace 1, and a separation mechanism 2 for increasing the speed and removing impurities of the high-temperature flue gas inside the furnace 1 is installed at one end of the preheating mechanism 4; the separation mechanism 2 includes a booster cylinder 22, a booster cylinder 22 is provided on one side of the furnace 1, the inside of the booster cylinder 22 is rotatably connected to the turbine 23, and the surface of the booster cylinder 22 is installed with a motor 21 for driving the turbine 23 to rotate; the side wall of the booster cylinder 22 is connected to the cyclone separator 24, and the exhaust pipe 25 is installed in the center of the side wall of the cyclone separator 24. A smoke exhaust pipe 11 is installed on the surface of the furnace 1, and the smoke exhaust pipe 11 is connected to the center of the bottom surface of the booster cylinder 22. When the fuel is burned inside the furnace 1, the high-temperature flue gas generated during the combustion process is discharged through the smoke exhaust pipe 11, and part of the smoke enters the inside of the booster cylinder 22. At this time, the motor 21 drives the turbine 23 to rotate rapidly inside the booster cylinder 22, increasing the flow rate of the smoke, so that the smoke quickly enters the inside of the cyclone separator 24, and most of the smoke in the smoke is deposited inside the cyclone separator 24. The smoke that has been dusted quickly enters the inside of the preheating cylinder 41 through the exhaust pipe 25.

[0020] The feed sleeve 3 is connected to a heat exchange mechanism 5 for quickly preheating part of the ammonia and oxygen. The preheating mechanism 4 includes a preheating tube 41. The preheating tube 41 is on one side of the furnace 1, and the separation mechanism 2 is installed tangentially on the side wall of the preheating tube 41; one side of the preheating tube 41 is fixedly connected to a partition 42, and a plurality of first nozzles 43 and second nozzles 44 are installed on the side wall of the partition 42, one end of the second nozzle 44 is fixedly connected to an air intake joint 45 with an arc-shaped side wall, and one end of the inclined air intake joint 45 is funnel-shaped; the first nozzle 43 with a funnel-shaped end is inclined on the surface of the partition 42, and the air outlet of the first nozzle 43 and the air inlet of the air intake joint 45 are facing the edge of the preheating tube 41, and the exhaust pipe 25 is tangentially connected to the preheating tube 41; the flue gas inside the exhaust pipe 25 is quickly discharged from the tangential direction The smoke flows into the preheating tube 41 to make the gas rotate rapidly clockwise inside the preheating tube 41. The baffle 42 blocks the smoke and makes the smoke ejected through the nozzle. The side wall of the air inlet joint 45 is arc-shaped and faces the edge of the preheating tube 41, so that the smoke rotating inside the preheating tube 41 quickly enters the air inlet joint 45, and is accelerated and turned inside the funnel-shaped air inlet joint 45, and then is ejected toward the center of the heat exchange tube 52 through the second nozzle 44. The smoke ejected from the first nozzle 43 is inclined to the inner wall of the preheating tube 41, so that the smoke rotates along the inner wall of the preheating tube 41, thereby increasing the contact probability between the smoke and the heat exchange tube 52 and facilitating the heating of the airflow inside the heat exchange tube 52. A smoke pipe 9 is installed at one end of the preheating tube 41, so that the smoke inside the preheating tube 41 is discharged through the smoke pipe 9.

[0021] The heat exchange mechanism 5 is located inside the preheating mechanism 4, and the heat exchange mechanism 5 includes a storage tube 51. The storage tube 51 is installed at the other end of the preheating tube 41, and the storage tube 51 with a funnel shape inside is connected to the feed sleeve 3; a plurality of spiral heat exchange tubes 52 are installed at one end of the storage tube 51. When the airflow formed by the mixture of ammonia and oxygen enters the interior of the storage tube 51, a plurality of spiral heat exchange tubes 52 are installed at one end of the storage tube 51, and the airflow is diverted into the interior of the plurality of heat exchange tubes 52, thereby accelerating the heat exchange efficiency of the airflow inside the preheating tube 41. The inner diameter of the heat exchange tube 41 is much smaller than that of the storage tube 51, thereby increasing the flow rate of the airflow inside the heat exchange tube 52, so that the airflow rotates and flows rapidly along the heat exchange tube 52, and the airflow forms turbulence inside the heat exchange tube, thereby further improving the heat exchange efficiency. The airflow spirally rotates inside the heat exchange tube 52, thereby increasing the heat exchange distance of the airflow; the heat exchange tube 52 is composed of a plurality of side walls. The heat exchange tube 52 is composed of a first connecting tube 521, a second connecting tube 522 and a connecting tube 523 which are arranged obliquely and are in a semi-circular shape. The inner diameter of the first connecting tube 521 is smaller than the inner diameter of the second connecting tube 522, and the adjacent first connecting tubes 521 and second connecting tubes 522 are connected through the connecting tube 523. Due to the different inner diameters of the connecting tubes, when the airflow flows inside the connecting tubes, the flow velocity of the airflow inside the connecting tubes is changed by the inner diameter of the connecting tubes, and the airflow inside the connecting tubes is disturbed, thereby improving the heat exchange efficiency of the airflow inside the heat exchange tube 52 and improving the temperature of the gas inside the heat exchange tube 52. When the airflow flows inside the heat exchange tube 52, the flue gas ejected from the second nozzle 44 flows rapidly at the center of the heat exchange tube 52. According to the Bernoulli principle, the flue gas flowing rapidly at the center of the second nozzle 44 generates suction, so that the flue gas at the inner edge of the preheating tube 41 moves toward the direction of the heat exchange tube 52 (as shown in the attached figure). Figure 3 As shown in the figure, the dotted arrow in the figure is the movement direction of the flue gas), the flow rate of the gas around the heat exchange tube 52 is increased, more high-temperature flue gas contacts the side wall of the heat exchange tube 52, and the flue gas directly impacts the surface of the heat exchange tube, thereby increasing the convection heat transfer coefficient and facilitating the heating of the airflow inside the heat exchange tube 52.

[0022] A feed sleeve 3 for conveying pulverized coal, ammonia and oxygen is installed in the center of the interior of the preheating mechanism 4, and a plurality of spoiler mechanisms 6 for improving the heat exchange effect are installed on the side wall of the heat exchange mechanism 5; the spoiler mechanism 6 includes a fixed shaft 63, and a plurality of fixed shafts 63 and a mounting pipe 62 are installed in the center of the side wall of the heat exchange tube 52. The side of the mounting pipe 62 connected to the heat exchange tube 52 is in a truncated cone structure, which increases the contact area between the mounting pipe 62 and the heat exchange tube 52 and improves the mounting pipe 62 in the The stability of the side wall of the heat exchange tube 52; the side walls of the fixed shaft 63 are respectively installed with fan blades 61, eccentric blocks 64 and twisted irons 65, the interior of the mounting tube 62 is rotatably connected to the eccentric block 64 and the fixed shaft 63, and the interior of the heat exchange tube 52 is installed with multiple twisted irons 65 that are rotatably connected, and a sealing ring 66 is installed at the connection between the fixed shaft 63 and the heat exchange tube 52 to increase the sealing performance of the connection between the fixed shaft 63 and the heat exchange tube 52 and avoid air leakage inside the heat exchange tube 52. In the process of airflow flowing at the center of the heat exchange tube 52, the smoke ejected from the second nozzle 44 drives the fan blade 61, the fixed shaft 63, the eccentric block 64, and the twisted iron 65 to rotate, and the twisted iron 65 rotates inside the heat exchange tube 52, thereby enhancing the airflow disturbance inside the heat exchange tube 52 and destroying the flow boundary layer inside the heat exchange tube 52 to increase heat transfer. At the same time, the movement direction of the airflow generated by the rotation of the fan blade 61 is different from the flow direction of the smoke, disturbing the gas flowing at the center of the heat exchange tube 52, further improving the heat exchange efficiency between the smoke and the gas inside the heat exchange tube 52. During the rotation of the fixed shaft 63, the eccentric block 64 is driven to rotate rapidly in the mounting tube 62. The centrifugal force generated by the rotation of the eccentric block 64 obtains an exciting force, which is transmitted to the mounting tube 62 and the heat exchange tube 52 through the fixed shaft 63, so that the elastic heat exchange tube 52 vibrates slightly inside the preheating cylinder 41, which is convenient for removing the smoke adsorbed on the surface of the heat exchange tube 52, avoiding the adsorption of a large amount of smoke inside the heat exchange tube 52 to affect the heat exchange efficiency. The vibration of the heat exchange tube 52 continuously disturbs the flow boundary layer of the gas, further improving the heat exchange efficiency and increasing the temperature of the gas inside the heat exchange tube 52.

[0023] One end of the heat exchange mechanism 5 is equipped with an ignition mechanism 7 for quickly igniting the preheated ammonia. The ignition mechanism 7 also includes a first ignition tube 72, which is fixedly connected to the center of the interior of the partition 42, and an igniter 71 is installed inside the first ignition tube 72; a funnel-shaped air inlet pipe 53 is installed on the side wall of the heat exchange tube 52, and the air inlet pipe 53 is obliquely tangently connected to the interior of the first ignition tube 72, and the heated ammonia and oxygen enter the interior of the first ignition tube 72 from the tangential direction through the air inlet pipe 53, so that the airflow continuously rotates inside the first ignition tube 72 to form a vortex, so that the ammonia and oxygen are mixed more evenly, and the igniter 71 quickly ignites the evenly mixed and fully heated ammonia and oxygen, so that the ammonia undergoes primary combustion inside the first ignition tube 72.

[0024] The ignition mechanism 7 includes a second ignition tube 73, which is fixed to the side wall of the preheating tube 41, and the interior of the second ignition tube 73 is connected to the coal powder pipe 32 and the other air intake pipes 31. The interiors of the first ignition tube 72 and the second ignition tube 73 are both funnel-shaped. When the ignited ammonia enters the interior of the second ignition tube 73 through the first ignition tube 72, the ignited ammonia has a large flow rate and converges to the center of the second ignition tube 73 through the funnel-shaped second ignition tube 73. At this time, the coal powder and the remaining ammonia enter the interior of the second ignition tube 73, and the ignited ammonia pushes the coal powder and the remaining ammonia and oxygen to converge toward the center of the second ignition tube 73 to mix them quickly and ignite them, so that the ignited coal powder and ammonia are sprayed into the interior of the furnace 1 through the second ignition tube 73, realizing the secondary combustion of the coal powder and ammonia and accelerating the ignition efficiency.

[0025] One end of the ignition mechanism 7 is provided with a mixing mechanism 8 for uniformly mixing the flame, ammonia, pulverized coal and oxygen; the mixing mechanism 8 includes a clamping ring 84, the inner part of the discharge port of the feed sleeve 3 is rotatably connected to the clamping ring 84, and the clamping ring 84 with a circular cross-section is fixedly connected to the fixing ring 82; a plurality of protrusions 83 are obliquely installed on the side wall of the fixing ring 82, and the protrusions 83 are located at the outlet of the first ignition tube 72; the side wall of the fixing ring 82 is fixedly connected to a spiral mixing ring 81, and the diameter of the mixing ring 81 gradually decreases toward the outlet of the second ignition tube 73; the inner part of the second ignition tube 73 is rotatably connected to the mixing ring 81; when the ignition When the burning ammonia flows inside the first ignition tube 72, the ammonia slides over the side wall of the inclined protrusion 83, thereby pushing the protrusion 83, the fixing ring 82 and the mixing ring 82 to rotate. The mixing ring 82 is spiral and its diameter gradually decreases toward the outlet of the second ignition tube 73. The pulverized coal, ammonia and oxygen sprayed from the inside of the feed sleeve 3 enter the inside of the mixing ring 82. The mixing ring 82 rotates to mix the three. The spiral mixing ring 82 rotates to make the pulverized coal, ammonia and oxygen gradually converge toward the center of the inside of the second ignition tube 73. The three collide and mix with each other, so that the pulverized coal, ammonia and oxygen are evenly mixed.

[0026] The feed sleeve 3 is composed of a plurality of air inlet pipes 31 and pulverized coal pipes 32, which are arranged alternately in sequence. The outermost air inlet pipe 31 is connected to the storage pipe 51, and a mixture of oxygen and ammonia is transported inside the air inlet pipe 31 to facilitate the continuous transportation of pulverized coal, ammonia and oxygen into the furnace 1.

[0027] The use principle of the pre-combustion device of the ammonia-coal mixed combustion furnace provided by the present invention is: coal powder, ammonia and oxygen are continuously transported to the interior of the furnace 1 through the feed sleeve 3, and the fuel is burned in the furnace 1 to generate high-temperature flue gas, which is discharged through the exhaust pipe 11, and part of the flue gas enters the interior of the booster cylinder 22. At this time, the motor 21 drives the turbine 23 to rotate rapidly inside the booster cylinder 22, increasing the flow rate of the flue gas, so that the flue gas quickly enters the interior of the cyclone separator 24, and most of the smoke in the smoke is deposited in the interior of the cyclone separator 24. The dust-removed smoke quickly rushes into the interior of the preheating cylinder 41 from a tangential direction through the exhaust pipe 25, so that the gas is The interior of the preheating tube 41 rotates rapidly clockwise, and the partition 42 blocks the smoke, allowing the smoke to be ejected through the nozzle. The side wall of the air intake joint 45 is arc-shaped and faces the edge of the preheating tube 41, so that the smoke rotating inside the preheating tube 41 quickly enters the interior of the air intake joint 45, and is accelerated and turned inside the funnel-shaped air intake joint 45, and then is ejected toward the center of the heat exchange tube 52 through the second nozzle 44. The smoke ejected from the first nozzle 43 is inclined to rush toward the inner side wall of the preheating tube 41, so that the smoke rotates along the inner side wall of the preheating tube 41, thereby increasing the contact probability between the smoke and the heat exchange tube 52 and facilitating the heating of the airflow inside the heat exchange tube 52. The airflow formed by the mixture of ammonia and oxygen inside the outermost intake pipe 31 enters the interior of the storage tube 51. A plurality of spiral heat exchange tubes 52 are installed at one end of the storage tube 51. The airflow is diverted into the plurality of heat exchange tubes 52, thereby accelerating the heat exchange efficiency of the airflow inside the preheating tube 41. The inner diameter of the heat exchange tube 41 is much smaller than that of the storage tube 51, thereby increasing the flow rate of the airflow inside the heat exchange tube 52, causing the airflow to rotate and flow rapidly along the heat exchange tube 52, and forming turbulence inside the heat exchange tube, thereby further improving the heat exchange efficiency. The airflow spirally rotates inside the heat exchange tube 52, thereby increasing the heat exchange distance of the airflow. When the airflow flows inside the heat exchange tube 52, the flue gas ejected from the second nozzle 44 flows rapidly at the center of the heat exchange tube 52. According to the Bernoulli principle, the flue gas flowing rapidly in the center of the second nozzle 44 generates suction, causing the flue gas at the inner edge of the preheating tube 41 to move toward the heat exchange tube 52, thereby increasing the flow rate of the gas around the heat exchange tube 52, allowing more high-temperature flue gas to contact the side wall of the heat exchange tube 52, and allowing the flue gas to directly impact the surface of the heat exchange pipe, thereby increasing the convection heat transfer coefficient and facilitating heating of the airflow inside the heat exchange tube 52.In the process of airflow flowing at the center of the heat exchange tube 52, the smoke ejected from the second nozzle 44 drives the fan blade 61, the fixed shaft 63, the eccentric block 64, and the twisted iron 65 to rotate, and the twisted iron 65 rotates inside the heat exchange tube 52, thereby enhancing the airflow disturbance inside the heat exchange tube 52 and destroying the flow boundary layer inside the heat exchange tube 52 to increase heat transfer. At the same time, the movement direction of the airflow generated by the rotation of the fan blade 61 is different from the flow direction of the smoke, disturbing the gas flowing at the center of the heat exchange tube 52, further improving the heat exchange efficiency between the smoke and the gas inside the heat exchange tube 52. During the rotation of the fixed shaft 63, the eccentric block 64 is driven to rotate rapidly in the mounting tube 62. The centrifugal force generated by the rotation of the eccentric block 64 obtains an exciting force, which is transmitted to the mounting tube 62 and the heat exchange tube 52 through the fixed shaft 63, so that the elastic heat exchange tube 52 vibrates slightly inside the preheating cylinder 41, which is convenient for removing the smoke adsorbed on the surface of the heat exchange tube 52, avoiding the adsorption of a large amount of smoke inside the heat exchange tube 52 to affect the heat exchange efficiency. The vibration of the heat exchange tube 52 continuously disturbs the flow boundary layer of the gas, further improving the heat exchange efficiency and increasing the temperature of the gas inside the heat exchange tube 52. The heated ammonia and oxygen in the heat exchange tube 52 enter the first ignition tube 72 from a tangential direction through the air inlet pipe 53, so that the airflow continuously rotates in the first ignition tube 72 to form a vortex, so that the ammonia and oxygen are mixed more evenly, and the igniter 71 quickly ignites the ammonia and oxygen that are evenly mixed and fully heated, so that the ammonia is burned in the first ignition tube 72; when the ignited ammonia flows in the first ignition tube 72, the ammonia slides over the side wall of the inclined protrusion 83, thereby driving the protrusion 83, the fixing ring 82 and the mixing ring 82 to rotate. The mixing ring 82 is spiral and its diameter gradually decreases toward the outlet of the second ignition tube 73, and the coal powder, ammonia and oxygen sprayed from the feed sleeve 3 are discharged. The gas enters the interior of the mixing ring 82, and the mixing ring 82 rotates to mix the three, and the spiral mixing ring 82 rotates to make the coal powder, ammonia and oxygen gradually converge toward the center of the inside of the second ignition tube 73, and the three collide and mix with each other, so that the coal powder, ammonia and oxygen are evenly mixed; and the ignited ammonia has a large flow rate and converges to the center of the second ignition tube 73 through the funnel-shaped second ignition tube 73. At this time, the coal powder and the remaining ammonia enter the interior of the second ignition tube 73, and the ignited ammonia pushes the coal powder and the remaining ammonia and oxygen to converge toward the center of the second ignition tube 73 to mix quickly and ignite them, so that the ignited coal powder and ammonia are sprayed into the interior of the furnace 1 through the second ignition tube 73, realizing the secondary combustion of coal powder and ammonia, and accelerating the ignition and combustion efficiency of the fuel.

[0028] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A pre-combustion device for an ammonia-coal mixed combustion furnace, characterized in that: include: A preheating mechanism (4), the preheating mechanism (4) being installed on one side of the furnace (1), and a separation mechanism (2) for increasing the speed and removing impurities of high-temperature flue gas inside the furnace (1) being installed at one end of the preheating mechanism (4); A feed sleeve (3) for conveying pulverized coal, ammonia and oxygen is installed at the center of the preheating mechanism (4); the feed sleeve (3) is connected to a heat exchange mechanism (5) for quickly preheating part of the ammonia and oxygen; the heat exchange mechanism (5) is located inside the preheating mechanism (4); and a plurality of turbulent mechanisms (6) for improving the heat exchange effect are installed on the side wall of the heat exchange mechanism (5); an ignition mechanism (7) for quickly igniting the preheated ammonia is provided at one end of the heat exchange mechanism (5); and a mixing mechanism (8) for evenly mixing the flame, ammonia, pulverized coal and oxygen is provided at one end of the ignition mechanism (7); The preheating mechanism (4) comprises a preheating tube (41), the preheating tube (41) being located on one side of the furnace (1), and the separation mechanism (2) being installed tangentially to the side wall of the preheating tube (41); one side of the preheating tube (41) is fixedly connected to a partition (42), and a plurality of first nozzles (43) and second nozzles (44) are installed on the side wall of the partition (42), one end of the second nozzle (44) is fixedly connected to an air intake joint (45) having an arc-shaped side wall, and one end of the air intake joint (45) which is arranged obliquely is in a funnel-shaped structure; The heat exchange mechanism (5) comprises a storage tube (51), the other end of the preheating tube (41) is equipped with the storage tube (51), the storage tube (51) having a funnel-shaped interior is connected to the feed sleeve (3); a plurality of spiral heat exchange tubes (52) are installed at one end of the storage tube (51), the heat exchange tube (52) is composed of a plurality of first connecting tubes (521), second connecting tubes (522) and connecting tubes (523) having side walls inclined and semi-annular, the inner diameter of the first connecting tube (521) being smaller than the inner diameter of the second connecting tube (522), and adjacent first connecting tubes (521) and second connecting tubes (522) are connected via the connecting tube (523); The spoiler mechanism (6) comprises a fixed shaft (63); a plurality of fixed shafts (63) and a mounting tube (62) are mounted in the center of the side wall of the heat exchange tube (52); a side of the mounting tube (62) connected to the heat exchange tube (52) is in a truncated cone-shaped structure; a fan blade (61), an eccentric block (64) and a twisted iron (65) are mounted on the side wall of the fixed shaft (63), respectively; the eccentric block (64) and the fixed shaft (63) are rotatably connected inside the mounting tube (62); and a plurality of twisted irons (65) are rotatably mounted inside the heat exchange tube (52); and a sealing ring (66) is mounted at the connection between the fixed shaft (63) and the heat exchange tube (52).

2. The pre-combustion device of the ammonia-coal mixed combustion furnace according to claim 1, characterized in that: The separation mechanism (2) comprises a booster cylinder (22). A booster cylinder (22) is provided on one side of the furnace (1). The interior of the booster cylinder (22) is rotatably connected to a turbine (23), and a motor (21) for driving the turbine (23) to rotate is installed on the surface of the booster cylinder (22); the side wall of the booster cylinder (22) is connected to a cyclone separator (24), and an exhaust pipe (25) is installed in the center of the side wall of the cyclone separator (24).

3. The pre-combustion device of the ammonia-coal mixed combustion furnace according to claim 2, characterized in that: A smoke exhaust pipe (11) is installed on the surface of the furnace (1), and the smoke exhaust pipe (11) is connected to the center of the bottom surface of the boost cylinder (22).

4. The pre-combustion device of the ammonia-coal mixed combustion furnace according to claim 2, characterized in that: The exhaust pipe (25) is tangentially connected to the preheating tube (41), and the first nozzle (43) having a funnel-shaped end is arranged obliquely on the surface of the partition (42), and the air outlet of the first nozzle (43) and the air inlet of the air inlet joint (45) are oriented toward the edge of the preheating tube (41).

5. The pre-combustion device of the ammonia-coal mixed combustion furnace according to claim 1, characterized in that: The feed sleeve (3) is formed by a plurality of air intake pipes (31) and coal powder pipes (32) being assembled together, the air intake pipes (31) and the coal powder pipes (32) being arranged alternately in sequence, and the outermost air intake pipe (31) is connected to the storage pipe (51).

6. The pre-combustion device of the ammonia-coal mixed combustion furnace according to claim 5, characterized in that: The ignition mechanism (7) comprises a second ignition tube (73), the second ignition tube (73) being fixed to the side wall of the preheating tube (41), and the interior of the second ignition tube (73) being in communication with the pulverized coal pipe (32) and other air intake pipes (31).

7. The pre-combustion device of the ammonia-coal mixed combustion furnace according to claim 6, characterized in that: The ignition mechanism (7) further comprises a first ignition tube (72), the first ignition tube (72) being fixedly connected to the center of the interior of the partition (42), and an igniter (71) being installed inside the first ignition tube (72); a funnel-shaped air inlet pipe (53) is installed on the side wall of the heat exchange tube (52), and the air inlet pipe (53) is connected to the interior of the first ignition tube (72) at an inclined tangent.

8. The pre-combustion device of the ammonia-coal mixed combustion furnace according to claim 7, characterized in that: The mixing mechanism (8) comprises a clamping ring (84), the clamping ring (84) is rotatably connected to the inside of the discharge port of the feed sleeve (3), and the clamping ring (84) with a circular cross-section is fixedly connected to a fixed ring (82); a plurality of protrusions (83) are obliquely installed on the side wall of the fixed ring (82), and the protrusions (83) are located at the outlet of the first ignition tube (72); the side wall of the fixed ring (82) is fixedly connected to a spiral mixing ring (81), and the diameter of the mixing ring (81) gradually decreases toward the outlet of the second ignition tube (73).

9. The pre-combustion device of the ammonia-coal mixed combustion furnace according to claim 8, characterized in that: The interiors of the first ignition tube (72) and the second ignition tube (73) are both funnel-shaped structures, and the interior of the second ignition tube (73) is rotatably connected to the mixing ring (81).

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