Heat feed adjusting mechanism and pulverized coal preparation equipment thereof

Abstract

The application discloses a heat sending adjusting mechanism and a pulverized coal preparation equipment thereof, and relates to the technical field of industrial kiln waste heat recycling, which comprises a directional collection component, a spiral flow guide heat exchange component and a heat medium distribution and conveying component. The directional collection component comprises an asymmetric cover body and a plurality of spiral flow guide fins. The included angle between the asymmetric cover body close to the side wall surface of the kiln body and the vertical direction is 30-45 degrees, and the included angle between the asymmetric cover body away from the side wall surface of the kiln body and the vertical direction is 60-75 degrees. The plurality of spiral flow guide fins are arranged on the inner wall of the asymmetric cover body. Through the cooperative matching of the directional collection component, the spiral flow guide heat exchange component and the heat medium distribution and conveying component, the inherent contradictions of kiln port waste gas diffusion overflow, large heat loss of the split system and heat exchange surface scaling and blockage under high dust working conditions are effectively improved. In the directional collection component, the asymmetric cover body matches the natural diffusion direction of the waste gas to reduce the mixing of cold air, and the spiral flow guide fins guide the airflow to form stable pre-swirl, thereby creating uniform flow field conditions for the rear-end heat exchange.

Description

Technical Field

[0001] This invention relates to the field of industrial kiln waste heat recovery and utilization technology, specifically to a heat delivery and regulation mechanism and its coal powder preparation equipment. Background Technology

[0002] The heat delivery and adjustment mechanism and its coal powder preparation equipment are the core process equipment for rotary kiln waste heat recovery and raw coal preheating and drying. They are key units that determine the waste heat utilization rate, coal powder moisture stability, system operation reliability and overall energy consumption of the production line.

[0003] Existing rotary kiln waste heat recovery and raw coal preheating and drying processes mostly employ a scheme of gas collection hoods, independent heat exchangers, and separate series-connected pipelines. The waste gas collection end uses a semi-open hood to collect the flue gas overflowing from the kiln opening, while the heat exchange end uses shell-and-tube heat exchangers to recover waste heat. All equipment is connected in series via pipelines. However, under conditions of fluctuating kiln operating conditions, high dust content in the waste gas, and differentiated preheating requirements for raw coal solids and combustion gases, this scheme has the following limitations: conventional gas collection hoods have a symmetrical structure, causing the heated waste gas to diffuse away from the kiln body due to buoyancy; the hood's alignment with the diffusion direction is not high, and the mixing of cold air leads to a decrease in calorific value; collection and transportation... With separate heat exchangers, the pipelines only serve a transport function without heat exchange, resulting in significant heat loss along the way. The numerous flange connection points lead to air leakage and increased heat dissipation area, resulting in low system thermal efficiency. Shell-and-tube heat exchangers lack self-cleaning capabilities, causing dust to accumulate and form scale on the outer walls of the heat exchange tubes, leading to increased heat exchange resistance and requiring shutdown for cleaning. Single-loop centralized heat supply can only cover a single terminal, making it difficult to accommodate the different distribution of raw coal solid preheating and combustion gas preheating. Heat regulation relies on the opening degree of the main pipe valve and temperature detection, which lags behind changes in kiln operating conditions. The operational reliability of valves and detection elements will also decrease in high-temperature and high-dust environments. Summary of the Invention

[0004] The purpose of this invention is to provide a heat delivery and regulation mechanism and its coal powder preparation equipment to solve the problems mentioned in the background art, such as the low collection efficiency caused by the poor matching degree between the conventional gas collection hood and the direction of waste gas diffusion, the heat loss along the way and the low system thermal efficiency caused by the separate setting of waste gas collection, transportation and heat exchange, and the difficulty of taking into account the differentiated distribution needs of raw coal solid preheating and combustion gas preheating by a single pipeline centralized heat delivery.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] This invention provides a heat delivery and regulation mechanism, including a directional collection component, a spiral flow heat exchange component, and a heat medium distribution and delivery component;

[0007] The directional collection component includes an asymmetrical cover and multiple spiral guide fins. The angle between the wall surface of the asymmetrical cover near the kiln body and the vertical direction is 30° to 45°, and the angle between the wall surface of the asymmetrical cover away from the kiln body and the vertical direction is 60° to 75°. The multiple spiral guide fins are all located on the inner wall of the asymmetrical cover and are spirally twisted along the height direction of the asymmetrical cover.

[0008] The spiral heat exchange assembly includes a heat exchange outer cylinder, a central main shaft, a first radial through hole, a second radial through hole, and an integral spiral blade. The central main shaft is coaxially inserted inside the heat exchange outer cylinder. The integral spiral blade is disposed on the outer wall of the central main shaft. The integral spiral blade has a cavity that extends along the blade extension direction inside. An annular gap is left between the outer edge of the integral spiral blade and the inner wall of the heat exchange outer cylinder.

[0009] The central spindle has an axial blind hole at the left end as an oil inlet channel and an axial blind hole at the right end as an oil return channel. The oil inlet channel is connected to the beginning of the cavity through a first radial through hole, and the oil return channel is connected to the end of the cavity through a second radial through hole.

[0010] The heat medium distribution and delivery assembly includes a distributor, the oil inlet of which is connected to the oil return channel.

[0011] Preferably, the directional collection assembly further includes a hanging rod, multiple sealing curtains, multiple counterweights, and air ducts. The multiple sealing curtains are suspended below the asymmetrical cover, and the multiple counterweights are sewn to the lower ends of the multiple sealing curtains. The asymmetrical cover is suspended and fixed by multiple hanging rods.

[0012] Preferably, the plurality of spiral guide fins are evenly arranged along the circumference of the inner wall of the asymmetric cover, the plurality of spiral guide fins have a trapezoidal gradually changing cross section that is wider at the bottom and narrower at the top, and the twisting direction of the plurality of spiral guide fins is consistent with the rotation direction of the integrated spiral blade.

[0013] Preferably, the spiral heat exchange assembly further includes a first rotary joint, a second rotary joint, and a variable frequency geared motor. The first rotary joint is installed on the left end of the central spindle and communicates with the oil inlet channel. The second rotary joint is installed on the right end of the central spindle and communicates with the oil return channel. The variable frequency geared motor is connected to the central spindle through a transmission mechanism and drives the central spindle to rotate.

[0014] Preferably, the outer wall of the heat exchange outer cylinder is fitted with a metal hanger, and the two ends of the heat exchange outer cylinder are respectively provided with a first flange end cover and a second flange end cover. An air inlet is opened at the lower part of the first flange end cover. The top of the asymmetric cover is connected to the air inlet through a duct. A three-way air distribution valve is connected at the lower part of the second flange end cover. The air inlet and the three-way air distribution valve are both located below the central main shaft axis. The three-way air distribution valve has one inlet and two outlets.

[0015] Preferably, the heat medium distribution and conveying assembly further includes an oil inlet pipe, the distributor is a vertical cylindrical pressure-bearing sealed tank, the bottom of the distributor is provided with a support, and the oil inlet of the distributor is connected to the oil return channel through the oil inlet pipe.

[0016] Preferably, the heat medium distribution and delivery assembly further includes a first heating pipeline, a second heating pipeline and a third heating pipeline. The first heating pipeline is located at the bottom of the distributor and is the main oil outlet pipeline. The second heating pipeline and the third heating pipeline are symmetrically connected to the outer wall of the distributor, and both the second heating pipeline and the third heating pipeline are branch oil outlet pipelines.

[0017] The present invention also provides a coal powder preparation device, including a vertical coal mill and the aforementioned heat supply and regulation mechanism; the spiral flow heat exchange component of the heat supply and regulation mechanism is mounted on the steel frame platform of the vertical coal mill; the heat medium distribution and conveying component of the heat supply and regulation mechanism includes a first heating pipeline, which is connected to the raw coal drying medium inlet of the vertical coal mill; the spiral flow heat exchange component of the heat supply and regulation mechanism includes a three-way air distribution valve, one outlet of which is connected to the air inlet channel of the drying chamber of the vertical coal mill via a pipeline, and the other outlet of which is connected to the exhaust gas dust removal system.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] In this invention, the synergistic cooperation of the directional collection component, the spiral flow-guiding heat exchange component, and the heat medium distribution and conveying component effectively improves the inherent contradictions of kiln exhaust gas diffusion and overflow, large heat loss in split systems, and scaling and clogging of heat exchange surfaces under high dust conditions. In the directional collection component, the asymmetric hood matches the natural diffusion direction of the exhaust gas to reduce the mixing of cold air, and the spiral guide fins guide the airflow to form a stable pre-swirling flow, creating uniform flow field conditions for downstream heat exchange. In the spiral flow-guiding heat exchange component, the integrated hollow spiral blades realize the integration of flow guidance and heat exchange functions, and the rotational movement... The self-cleaning effect prevents dust accumulation. The coaxial separation structure of the oil inlet and return channels inside the central main shaft only requires two radial through holes at the beginning and end to connect, which greatly reduces the risk of high-temperature leakage. In the heat medium distribution and conveying components, the main oil outlet at the bottom of the distributor prioritizes the preheating of raw coal solids, while the side branch oil outlets realize the cascade utilization of waste heat. The independent regulating valves of each pipeline adapt to different heat load changes. The downward shift of the exhaust gas inlet and outlet and the zoning of oil and gas eliminate spatial interference, significantly improve the system's heat recovery efficiency, stabilize the coal powder moisture index, and extend the continuous operation cycle of the equipment. Attached Figure Description

[0020] Figure 1 This is a perspective view of the main structure in this invention;

[0021] Figure 2 This is a side view of the three-dimensional structure in this invention;

[0022] Figure 3 This is a schematic diagram of the installation location structure of the directional collection component in this invention;

[0023] Figure 4 This is a schematic diagram showing the installation positions of the spiral guide fins, sealing curtain, and counterweight strip in this invention.

[0024] Figure 5 This is a schematic diagram of the installation positions of the asymmetric cover, the suspension rod, and the spiral guide fins in this invention;

[0025] Figure 6 This is a schematic diagram of the installation position structure of the spiral heat exchange component in this invention;

[0026] Figure 7 This is a schematic diagram of the installation position of the heat exchange outer cylinder and the metal hanger in this invention;

[0027] Figure 8 This is a schematic diagram showing the installation positions of the central spindle, oil inlet channel, and oil return channel in this invention.

[0028] Figure 9 for Figure 8 Enlarged 3D view at point A in the middle;

[0029] Figure 10 for Figure 8 Enlarged 3D view at point B;

[0030] Figure 11 This is a schematic diagram of the installation position of the heat medium distribution and delivery component in this invention;

[0031] Figure 12 This is a schematic diagram showing the installation positions of the first heating pipeline, the second heating pipeline, and the third heating pipeline in this invention.

[0032] In the diagram: 100, Directional collection assembly; 101, Asymmetric enclosure; 102, Hanger; 103, Spiral guide fins; 104, Sealing curtain; 105, Counterweight bar; 106, Duct; 200, Spiral flow heat exchange assembly; 201, Heat exchange outer cylinder; 202, Metal hanger; 203, First flange end cover; 204, Second flange end cover; 205, Air inlet; 206, Three-way air distribution valve; 207, Central spindle; 208, Oil inlet channel; 209, Return... Oil passage; 210, First radial through hole; 211, Second radial through hole; 212, Integrated spiral blade; 213, Cavity; 214, First rotary joint; 215, Second rotary joint; 216, Variable frequency geared motor; 300, Heat medium distribution and conveying assembly; 301, Distributor; 302, Support; 303, Oil inlet pipe; 304, First heating pipeline; 305, Second heating pipeline; 306, Third heating pipeline; 400, Pulverized coal vertical mill. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] like Figures 1-2 As shown, this embodiment provides a heat delivery and regulation mechanism, including a directional collection component 100, a spiral flow heat exchange component 200, and a heat medium distribution and conveying component 300. This mechanism uses the high-temperature waste gas overflowing from the kiln opening of an industrial kiln as a heat source. The directional collection component 100 captures the waste gas and forms a stable pre-swirling flow field. The spiral flow heat exchange component 200 realizes synchronous heat exchange between the waste gas and the heat transfer oil. Then, the heat medium distribution and conveying component 300 distributes the heat-exchanged high-temperature heat transfer oil to different heat-using terminals as needed. At the same time, the heat-exchanged waste gas is diverted through a three-way air distribution valve 206, with part of it being sent to a vertical coal mill 400 as an auxiliary drying medium and part of it being discharged into the tail gas dust removal system.

[0035] like Figures 3-5As shown, the directional collection assembly 100 includes an asymmetric shroud 101 and multiple spiral guide fins 103. The asymmetric shroud 101 is an irregularly shaped asymmetric frustum structure, formed by rolling and welding heat-resistant steel plates. Both the upper and lower openings are circular, with a short cylindrical section extending from the upper end, and a connecting flange welded to the end of the short cylindrical section. The wall surface of the asymmetric shroud 101 near the rotary kiln shell has an angle of 30° to 45° with the vertical direction, and the wall surface is relatively steep to avoid obstructing the maintenance space above the kiln. The wall surface away from the rotary kiln shell has an angle of 60° to 75° with the vertical direction, and the wall surface is relatively gentle, allowing the waste gas to flow towards the kiln shell due to buoyancy after heating. The asymmetrical structure, with its tilted upward mainstream direction, matches the natural diffusion trajectory of high-temperature exhaust gas, reducing the mixing of external cold air and improving the heat grade of the collected exhaust gas. The top of the asymmetrical hood 101 is suspended and fixed to the steel frame beam on the top of the kiln area workshop by four hanging rods 102. The upper end of the hanging rod 102 is bolted to the beam, and the lower end is welded to the mounting base on the outer wall of the top of the asymmetrical hood 101. The lower opening of the asymmetrical hood 101 is larger than the kiln opening. After installation, the bottom edge of the hood is a certain distance from the end face of the kiln opening, so that the exhaust gas is within the coverage area of ​​the asymmetrical hood 101 no matter which direction it drifts.

[0036] like Figures 4-5 As shown, multiple spiral guide fins 103 are evenly arranged along the inner circumference of the asymmetric cover 101, with a minimum of 6 fins. In this embodiment, 6 fins are used as an example. Each spiral guide fin 103 is made of heat-resistant steel plate, cut and bent. The outer root is continuously and fully welded to the inner wall of the asymmetric cover 101, and the inner free end extends suspended towards the center of the cover. The inner ends of each spiral guide fin 103 do not contact each other, and the central area naturally forms a circular main airflow channel. The spiral guide fins 103 are spirally twisted along the height direction of the asymmetric cover 101, that is, the spiral guide fins 103 are spirally twisted. The windward surface of 03 gradually deflects around the central axis of the asymmetric shroud 101 from the lower edge to the top outlet. The deflection direction is consistent with the rotation direction of the integrated spiral blade 212 at the rear end, so that the pre-swirling flow can form a synergistic effect with the rotation direction of the integrated spiral blade 212 after entering the heat exchange outer cylinder 201, reducing airflow resistance. The width of the spiral guide fin 103 gradually narrows from bottom to top, forming a trapezoidal gradient cross section that is wider at the bottom and narrower at the top. This matches the tapering line of the asymmetric shroud 101 from the bottom to the top, so that the airflow is smoothly gathered during the upward process.

[0037] like Figures 4-5As shown, multiple sealing curtains 104 are suspended around the lower opening edge of the asymmetric cover 101. Each sealing curtain 104 is a strip of aluminum silicate fiber cloth. Multiple sealing curtains 104 are arranged sequentially along the circumference, covering the entire lower circumference of the asymmetric cover 101. The upper end of each sealing curtain 104 is clamped and fixed to the outer edge of the lower edge of the asymmetric cover 101 by pressure strips and bolts. After the curtain is worn, the bolts are loosened and it is replaced individually. A counterweight strip 105 is sewn to the lower end of each sealing curtain 104. The counterweight strip 105 is a solid steel strip with a length consistent with the width of the curtain. It is wrapped inside the fabric at the lower end of the curtain and fixed by stitching. The function of 05 is to increase the weight at the lower end of the sealing curtain 104, so that the curtain remains sturdy after hanging down naturally and is not blown up by the hot air rushing from the kiln opening. It forms a flexible sealing barrier under the asymmetric cover 101, further reducing the intrusion of cold air from the bottom of the asymmetric cover 101. After installation, the counterweight 105 at the lower end of the sealing curtain 104 is a certain distance away from the end face of the rotary kiln cylinder. During the axial movement generated by the operation of the rotary kiln, the sealing curtain 104 is made of flexible material. When the kiln body pushes over, the curtain bends adaptively. When the kiln body moves back, the curtain returns to vertical under the gravity of the counterweight 105, always maintaining a close fit or slight gap with the surface of the kiln body.

[0038] like Figures 6-7 As shown, the spiral heat exchange assembly 200 includes a heat exchange outer cylinder 201, metal hangers 202, a first flange end cap 203, a second flange end cap 204, an air inlet 205, and a three-way air distribution valve 206. The heat exchange outer cylinder 201 is a seamless steel cylinder with a straight cylindrical body of equal diameter, horizontally placed on the steel maintenance platform on the upper left side of the pulverized coal vertical mill 400. The outer wall of the heat exchange outer cylinder 201 is wrapped with a layer of insulating rock wool, and the rock wool layer is covered with galvanized iron sheet for protection. Two sets of metal hangers 202 are evenly arranged along the axial direction on the outer wall of the heat exchange outer cylinder 201. The metal hangers 202 are welded from channel steel and are bolted to the steel frame beam of the platform. Their inner walls lock the outer wall of the heat exchange outer cylinder 201. The left end of the heat exchange outer cylinder 201 is welded with a first flange end cap 202, and the right end is welded with a second flange end cap 204. The flange end cover 204 has two circular steel plates at both ends. A main shaft mounting hole is opened at the center of the first flange end cover 203 for the left end of the central main shaft 207 to pass through. A high-temperature resistant graphite sliding bearing is installed in the main shaft mounting hole, and a graphite packing seal is provided on the outside of the bearing. An air inlet 205 is opened at a position about one-quarter of the cylinder diameter vertically offset downward from the center of the first flange end cover 203. The inner end of the air inlet 205 is connected to the inner cavity of the heat exchange outer cylinder 201. The short cylinder at the top of the asymmetric cover 101 is connected to the air inlet 205 through the air duct 106. The air duct 106 is a circular high-temperature resistant seamless steel pipe with an insulation layer on the outer wall. The lower flange of the air duct 106 is connected to the top flange of the asymmetric cover 101, and the upper flange of the air duct 106 is connected to the flange of the air inlet 205. A high-temperature resistant graphite spiral wound gasket is sandwiched between the flanges for sealing.

[0039] like Figure 8 As shown, the spiral heat exchange assembly 200 also includes a central main shaft 207 and an integrated spiral blade 212. The central main shaft 207 is coaxially inserted inside the heat exchange outer cylinder 201, and the integrated spiral blade 212 is disposed on the outer wall of the central main shaft 207. The left end of the central main shaft 207 is provided with an axial blind hole as an oil inlet channel 208, and the right end is provided with an axial blind hole as an oil return channel 209.

[0040] like Figures 9-10 As shown, the central spindle 207 is provided with a first radial through hole 210 and a second radial through hole 211. The oil inlet channel 208 is connected to the beginning of the cavity 213 through the first radial through hole 210, and the oil return channel 209 is connected to the end of the cavity 213 through the second radial through hole 211.

[0041] like Figures 6-7 As shown, a main shaft mounting hole is also opened at the center of the second flange end cover 204 to install a high-temperature resistant graphite sliding bearing and a graphite packing seal ring to support the right end of the central main shaft 207. An air outlet is opened at the vertically downward offset point of the center of the second flange end cover 204. The outside of the air outlet is connected to a three-way air distribution valve 206 through a flange. The valve body of the three-way air distribution valve 206 is welded from heat-resistant steel plate and has a rotatable fan-shaped valve core inside. The opening ratio of the two outlets can be manually adjusted by an external handle. The air inlet 205 and the three-way air distribution valve 206 are both located below the axis of the central main shaft 207 and are arranged eccentrically. This bottom-in and bottom-out airflow arrangement is combined with the oil and gas zoning arrangement to eliminate spatial interference. One outlet of the three-way air distribution valve 206 is connected to the air inlet channel of the drying chamber of the pulverized coal vertical mill 400 through a vertical pipe, and the other outlet is connected to the original tail gas dust removal system of the plant through a horizontal flue.

[0042] like Figure 8As shown, the central spindle 207 is a long cylindrical stepped shaft, forged entirely from 304 stainless steel. It coaxially penetrates the geometric center of the heat exchange outer cylinder 201, with its left and right ends extending outward from the central holes of the first flange end cover 203 and the second flange end cover 204, respectively. The internal oil passage of the central spindle 207 adopts a double-ended blind hole structure. An axial oil inlet blind hole is drilled at the center of the left end of the shaft, serving as an oil inlet channel 208. This blind hole extends to the right from the end of the shaft, reaching only to the shaft body position corresponding to the first integrated spiral blade 212, and does not continue to the right. The right end of the shaft has an axial return oil blind hole drilled at its center, serving as the return oil channel 209. This blind hole extends from the right end of the shaft to the left, reaching only to the shaft body position corresponding to the last integrated spiral blade 212. The oil inlet channel 208 and the return oil channel 209 are not connected to each other inside the main shaft. The intermediate shaft section between the two blind holes is a solid structure without any oil holes. This coaxially separated oil circuit structure only requires two radial through holes at the beginning and end to connect with the blade cavity 213, reducing the number of sealing surfaces inside the main shaft and lowering the risk of leakage of high-temperature heat transfer oil.

[0043] like Figure 8 As shown, the integral spiral blade 212 is continuously welded to the outer circumference of the central main shaft 207, extending from near the left end air inlet 205 inside the heat exchange outer cylinder 201 to near the right end air outlet. The integral spiral blade 212 is made of 304 stainless steel plate, with a streamlined airfoil-shaped cross-section. The leading edge faces the direction of the exhaust gas flow, with a rounded transition and a relatively large thickness. The trailing edge faces away from the direction of the exhaust gas flow and gradually narrows. A continuous sealed cavity 213 is opened inside the integral spiral blade 212, extending from head to tail along the blade extension direction. An annular gap is reserved between the outer edge of the integral spiral blade 212 and the inner wall of the heat exchange outer cylinder 201. The gap width is 8% to 12% of the inner diameter of the heat exchange outer cylinder 201. This annular gap forms a relatively static gas insulation layer between the blade and the cylinder wall. The main exhaust gas flows and rotates along the spiral channel between the blades, without directly scouring the cylinder wall, thus reducing heat loss to the outside through the cylinder wall.

[0044] like Figures 9-10 As shown, the cross-sectional shape of cavity 213 follows the shape of the blade; the first end of cavity 213 corresponds to the root position of the first blade and is connected to the oil inlet channel 208 of the central spindle 207 through the first radial through hole 210; the last end of cavity 213 corresponds to the root position of the last blade and is connected to the oil return channel 209 of the central spindle 207 through the second radial through hole 211; the first radial through hole 210 and the second radial through hole 211 are both circular through holes drilled radially from the outer wall of the spindle, and the hole diameter matches the flow channel cross-section of cavity 213.

[0045] like Figures 6-8As shown, after the left end of the central spindle 207 extends from the first flange end cover 203, the first rotary joint 214 and the driven sprocket of the transmission mechanism are installed in sequence. The first rotary joint 214 is a sleeve-type double-channel high-temperature resistant dynamic seal joint. Its rotating core is locked to the left end of the central spindle 207 through the flange. The central hole inside the rotating core is aligned and connected to the oil inlet channel 208. The fixed housing of the first rotary joint 214 is provided with an oil inlet interface, which is connected to the cold oil output end of the external heat transfer oil supply system through a pipeline. After the right end of the central spindle 207 extends from the second flange end cover 204, the second rotary joint 215 is installed. The rotating core of the second rotary joint 215 is connected to the central spindle through the flange. The right end of the shaft is locked, and the internal channel of the rotating core is aligned and connected with the return oil channel 209. The fixed housing of the second rotary joint 215 is provided with an oil outlet, which is connected to the distributor 301 through the oil inlet pipe 303. The variable frequency reduction motor 216 is installed on one side of the first flange end cover 203 of the heat exchange outer cylinder 201. The base of the variable frequency reduction motor 216 is fixed by anchor bolts. The drive sprocket is installed on the output shaft. The drive sprocket and the driven sprocket on the central main shaft 207 are connected by a closed-loop transmission chain. After the variable frequency reduction motor 216 is started, it drives the central main shaft 207 and the integrated spiral blade 212 welded on it to rotate synchronously through the chain drive. The speed is continuously adjustable through the frequency converter.

[0046] like Figures 11-12 As shown, the distributor 301 is a vertical cylindrical pressure-bearing sealed tank with elliptical arc-shaped heads at both ends. The cylinder is formed by rolling and welding Q345R container steel plate, and the outer wall is covered with aluminum silicate fiber insulation cotton. The outermost layer is wrapped with an aluminum shell. The main oil inlet is opened at the center of the top head of the distributor 301, which is connected to the oil outlet of the second rotary joint 215 through the oil inlet pipe 303. The oil inlet pipe 303 is a high-temperature resistant seamless alloy steel pipe. The main oil outlet is opened at the center of the bottom head of the distributor 301, which is connected to the first heating pipeline 304. The first heating pipeline 304 is laid vertically downward, and the lower end is connected to the raw coal drying medium inlet of the pulverized coal vertical coal mill 400 through a flange. The middle section of the pipeline can be connected in series with a manual throttling regulating valve and an insertion valve. Temperature sensor and target flow meter. The distributor 301 has two branch oil outlets symmetrically opened along the circumference of the cylinder side wall, which are respectively connected to the second heating pipeline 305 and the third heating pipeline 306. The two pipelines are laid horizontally outward. The far end of the second heating pipeline 305 is connected to the heat medium inlet of the rotary kiln combustion air preheater, and the far end of the third heating pipeline 306 is connected to the heat medium inlet of the plant heating heat exchange station. A manual throttling regulating valve can be connected in series in the middle section of each pipeline. The bottom of the distributor 301 is supported and fixed by three sets of brackets 302. The brackets 302 are made of angle steel welded into a triangular support structure. The upper end is welded to the bottom outer wall of the distributor 301, and the lower end is locked to the steel frame platform on the top of the pulverized coal vertical coal mill 400 by anchor bolts.

[0047] like Figures 1-2 As shown, this embodiment provides a pulverized coal preparation device, including a vertical pulverized coal mill 400, and the aforementioned heat supply and regulation mechanism; as Figure 1 and Figure 11 As shown, the first heating pipeline 304 is connected to the raw coal drying medium inlet of the pulverized coal vertical coal mill 400, transporting high-temperature heat transfer oil to the heat exchange device inside the pulverized coal vertical coal mill 400 for heating and drying the raw coal; as Figure 2 and Figure 7 As shown, one outlet of the three-way air distribution valve 206 is connected to the air inlet channel of the drying chamber of the pulverized coal vertical mill 400 through a pipeline, and the heat-exchanged waste gas is sent into the pulverized coal vertical mill 400 as an auxiliary drying medium to further utilize the waste heat of the waste gas; the other outlet of the three-way air distribution valve 206 is connected to the tail gas dust removal system, and the excess waste gas is discharged in compliance with the standards after dust removal treatment.

[0048] Usage Phase: After assembly, the heat supply and regulation mechanism and pulverized coal preparation equipment are put into use. The high-temperature exhaust gas overflowing from the rotary kiln outlet diffuses upward under the action of thermal buoyancy. The asymmetric hood 101, with its relatively gentle wall surface away from the kiln body, follows the mainstream direction of the exhaust gas and draws most of the exhaust gas into the hood. The sealing curtain 104 hangs down naturally under the gravity of the counterweight 105, maintaining a slight gap with the end face of the kiln body, preventing the exhaust gas from escaping from the edge of the hood and preventing external cold air from being drawn in. After entering the interior of the hood, the exhaust gas rises along the spiral channel between the spiral guide fins 103. Under continued guidance, the airflow is gradually twisted into a rotating flow. When it reaches the top outlet of the asymmetric shroud 101, a stable pre-swirling flow has been formed. The direction of the rotation is consistent with that of the integrated spiral blade 212 at the rear end. The pre-swirled exhaust gas enters the air inlet 205 at the left end of the heat exchange outer cylinder 201 through the air duct 106. Under the further guidance of the integrated spiral blade 212, it is pushed to the right along the spiral channel between the blades. The main stream of exhaust gas rotates and flows in the spiral channel, without directly scouring the inner wall of the heat exchange outer cylinder 201. The annular gap between the outer edge of the blade and the cylinder wall forms a gas insulation layer, which reduces the heat transfer of high temperature exhaust gas to the cylinder wall.

[0049] Meanwhile, the external oil supply system delivers ambient temperature heat transfer oil through the first rotary joint 214 into the oil inlet channel 208 of the central spindle 207. The heat transfer oil flows along the blind inlet hole to the shaft position corresponding to the first integrated spiral blade 212, and enters the first end of the cavity 213 through the first radial through hole 210. Within the cavity 213, it flows from left to right along the blade extension direction, absorbing heat transferred from the high-temperature exhaust gas outside the blade as it flows. The oil temperature gradually increases, and when it reaches the position of the last blade, the heated high-temperature heat transfer oil enters the return oil channel 209 of the central spindle 207 through the second radial through hole 211, flows out from the second rotary joint 215, and passes through the oil inlet pipe. The oil enters distributor 301 through channel 303. The high-temperature heat transfer oil is naturally divided within distributor 301. The main channel is sent vertically downward through the first heating pipeline 304 to the raw coal drying medium inlet of the pulverized coal vertical mill 400 to dry the raw coal entering the mill, meeting the main heat demand for raw coal drying. The auxiliary channels are sent to the combustion air preheater and the plant heating heat exchange station through the second heating pipeline 305 and the third heating pipeline 306, respectively, to realize the cascade utilization of waste heat. The return oil from each heat-using terminal is collected in the return oil main pipe through the return oil pipeline and flows back to the oil storage tank of the external oil supply system. After being pressurized by the circulating pump, it is sent back to the first rotary joint 214 to complete the closed circulation of the heat transfer oil. After the exhaust gas completes the heat exchange, its temperature decreases and it enters the three-way air distribution valve 206 from the right end of the heat exchange outer cylinder 201. One path of hot air is sent through a vertical pipe into the drying chamber of the coal powder vertical mill 400 to directly participate in the drying of raw coal, while the other path of exhaust gas is discharged into the tail gas dust removal system for treatment and then discharged in compliance with standards.

[0050] When the kiln is under normal and stable operating conditions, and the exhaust gas temperature and flow rate remain within the design range, the variable frequency reduction motor 216 operates at a preset speed. The rotation speed of the integrated spiral blade 212 is moderate, ensuring both the heat exchange effect between the exhaust gas and the heat transfer oil and preventing excessive airflow resistance. The three-way air distribution valve 206 distributes the exhaust gas flow according to a preset ratio, and most of the heat-exchanged exhaust gas is sent to the pulverized coal vertical mill 400 for auxiliary drying. The centrifugal force and airflow scouring effect generated by the rotation of the integrated spiral blade 212 effectively prevent dust from depositing on the blade surface and the inner wall of the heat exchange outer cylinder 201, keeping the heat exchange surface clean.

[0051] When the kiln operating conditions fluctuate, and the exhaust gas temperature or flow rate increases, the external control system automatically increases the speed of the variable frequency reduction motor 216 based on the temperature detection signal, accelerates the rotation speed of the integrated spiral blade 212, enhances the convective heat transfer between the exhaust gas and the blade wall, and simultaneously adjusts the opening of the three-way air distribution valve 206 to increase the exhaust gas flow rate into the pulverized coal vertical mill 400, making full use of the excess exhaust gas waste heat, and adjusting the opening of the regulating valve on the first heating pipeline 304 to increase the flow rate of heat transfer oil, thereby meeting the heat demand when the raw coal drying load increases.

[0052] When the dust content in the exhaust gas is high, the self-cleaning effect generated by the rotation of the integrated spiral blade 212 is more obvious. Under the action of centrifugal force, the dust is continuously thrown towards the cylinder wall, making it difficult for it to adhere and form scale on the blade surface. If a small amount of dust adheres to the cylinder wall, the speed of the variable frequency reduction motor 216 can be increased for a short time to enhance the flushing effect of the airflow, peel off the attached dust and carry it away with the airflow, eliminating the need to stop the machine for manual cleaning and extending the continuous operation cycle of the equipment.

[0053] When the kiln is temporarily shut down or the waste gas temperature is too low, the external control system automatically reduces the speed of the variable frequency reduction motor 216 or stops the motor to reduce the energy consumption of the equipment during idling. At the same time, it adjusts the three-way air distribution valve 206 to close the outlet to the pulverized coal vertical mill 400 and introduces all the waste gas into the tail gas dust removal system to prevent low-temperature waste gas from entering the pulverized coal vertical mill 400 and affecting the drying effect of the raw coal. After the kiln resumes normal operation and the waste gas temperature rises back to the set value, the system automatically restores the operating parameters of the corresponding working condition.

[0054] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A heat delivery and regulation mechanism, characterized in that, It includes a directional collection component (100), a spiral flow heat exchange component (200), and a heat medium distribution and delivery component (300). The directional collection component (100) includes an asymmetric cover (101) and multiple spiral guide fins (103). The angle between the wall of the asymmetric cover (101) near the kiln body and the vertical direction is 30° to 45°, and the angle between the wall of the asymmetric cover (101) away from the kiln body and the vertical direction is 60° to 75°. The multiple spiral guide fins (103) are all located on the inner wall of the asymmetric cover (101) and are spirally twisted along the height direction of the asymmetric cover (101). The spiral heat exchange assembly (200) includes a heat exchange outer cylinder (201), a central main shaft (207), a first radial through hole (210), a second radial through hole (211), and an integral spiral blade (212). The central main shaft (207) is coaxially inserted inside the heat exchange outer cylinder (201). The integral spiral blade (212) is disposed on the outer wall of the central main shaft (207). The integral spiral blade (212) has a cavity (213) extending along the blade extension direction inside. An annular gap is left between the outer edge of the integral spiral blade (212) and the inner wall of the heat exchange outer cylinder (201). The central spindle (207) has an axial blind hole at the left end as an oil inlet channel (208) and an axial blind hole at the right end as an oil return channel (209). The oil inlet channel (208) is connected to the beginning of the cavity (213) through a first radial through hole (210), and the oil return channel (209) is connected to the end of the cavity (213) through a second radial through hole (211). The heat medium distribution and delivery assembly (300) includes a distributor (301), the oil inlet of which is connected to the oil return channel (209).

2. The heat delivery and regulation mechanism according to claim 1, characterized in that: The directional collection assembly (100) also includes a hanging rod (102), multiple sealing curtains (104), multiple counterweights (105), and an air duct (106). The multiple sealing curtains (104) are suspended below the asymmetric cover (101), and the multiple counterweights (105) are sewn to the lower ends of the multiple sealing curtains (104). The asymmetric cover (101) is suspended and fixed by the multiple hanging rods (102).

3. The heat delivery and regulation mechanism according to claim 1, characterized in that: Multiple spiral guide fins (103) are evenly arranged along the inner circumference of the asymmetric cover (101). The multiple spiral guide fins (103) have a trapezoidal gradually changing cross section that is wider at the bottom and narrower at the top. The twisting direction of the multiple spiral guide fins (103) is consistent with the rotation direction of the integrated spiral blade (212).

4. The heat delivery and regulation mechanism according to claim 1, characterized in that: The spiral heat exchange assembly (200) further includes a first rotary joint (214), a second rotary joint (215), and a variable frequency geared motor (216). The first rotary joint (214) is installed on the left end of the central spindle (207) and communicates with the oil inlet channel (208). The second rotary joint (215) is installed on the right end of the central spindle (207) and communicates with the oil return channel (209). The variable frequency geared motor (216) is connected to the central spindle (207) through a transmission mechanism and drives the central spindle (207) to rotate.

5. The heat delivery and regulation mechanism according to claim 2, characterized in that: The outer wall of the heat exchange outer cylinder (201) is fitted with a metal hanger (202). The two ends of the heat exchange outer cylinder (201) are respectively provided with a first flange end cap (203) and a second flange end cap (204). The lower part of the first flange end cap (203) is provided with an air inlet (205). The top of the asymmetric cover (101) is connected to the air inlet (205) through a duct (106). The lower part of the second flange end cap (204) is connected to a three-way air distribution valve (206). The air inlet (205) and the three-way air distribution valve (206) are both located below the axis of the central main shaft (207). The three-way air distribution valve (206) has one inlet and two outlets.

6. The heat delivery and regulation mechanism according to claim 1, characterized in that: The heat medium distribution and conveying assembly (300) also includes an oil inlet pipe (303). The distributor (301) is a vertical cylindrical pressure-bearing sealed tank. The bottom of the distributor (301) is provided with a support (302). The oil inlet of the distributor (301) is connected to the oil return channel (209) through the oil inlet pipe (303).

7. The heat delivery and regulation mechanism according to claim 1, characterized in that: The heat medium distribution and delivery assembly (300) further includes a first heating pipeline (304), a second heating pipeline (305), and a third heating pipeline (306). The first heating pipeline (304) is located at the bottom of the distributor (301) and is the main oil outlet pipeline. The second heating pipeline (305) and the third heating pipeline (306) are symmetrically connected to the outer wall of the distributor (301), and both the second heating pipeline (305) and the third heating pipeline (306) are branch oil outlet pipelines.

8. A coal powder preparation device, comprising a vertical coal mill (400), characterized in that: It also includes the heat delivery and regulation mechanism as described in any one of claims 1 to 7; the spiral flow heat exchange component (200) of the heat delivery and regulation mechanism is mounted on the steel frame platform of the pulverized coal vertical mill (400); the heat medium distribution and conveying component (300) of the heat delivery and regulation mechanism includes a first heating pipeline (304), which is connected to the raw coal drying medium inlet of the pulverized coal vertical mill (400); the spiral flow heat exchange component (200) of the heat delivery and regulation mechanism includes a three-way air distribution valve (206), one outlet of the three-way air distribution valve (206) is connected to the air inlet channel of the drying chamber of the pulverized coal vertical mill (400) through a pipeline, and the other outlet of the three-way air distribution valve (206) is connected to the exhaust gas dust removal system.

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