On-line raw coal preheating device of pulverized coal preparation system

Abstract

The utility model discloses a raw coal on-line preheating device of a pulverized coal preparation system, and relates to the technical field of blast furnace ironmaking coal injection. A steam main pipe and an outlet main pipe are arranged on the outer side of a raw coal bunker, a plurality of steam branch pipes are connected between the steam main pipe and the outlet main pipe, and the steam branch pipes penetrate into the raw coal bunker at different heights of the raw coal bunker and penetrate out of the raw coal bunker after heat exchange structures are arranged on horizontal planes at the heights. The part, penetrating out of the raw coal bunker, of each steam branch pipe is also connected with a steam branch pipe drainage pipe; the outlet main pipe and each steam branch pipe drainage pipe are respectively connected with a drain valve; a steam branch pipe anti-collision device is fixedly arranged above each steam branch pipe in the raw coal bunker and is used for blocking impact and friction of raw coal on the steam branch pipes; in consideration that steam is discharged after the raw coal is preheated, a dust remover is further arranged at the top of the raw coal bunker for forced discharging; the raw coal preheating device is simple in structure, and the raw coal preheating effect is effectively improved; the water content of the preheated raw coal entering the mill is reduced, and the yield of the mill can be effectively improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to blast furnace ironmaking coal injection technical field, concretely is a coal powder preparation system raw coal online preheating device. BACKGROUND

[0002] Blast furnace coal injection technology has been one of main process technologies in modern blast furnace ironmaking process system, and the main function of the coal powder injected into the blast furnace is to replace part of the coke in the blast furnace, provide part of the heat source and reducing agent of the blast furnace ironmaking, so as to reduce coke ratio and reduce ironmaking cost.In actual production, a part of steel enterprises and coal enterprises, in order to further reduce cost, have to use some low-priced, poorer quality (including moisture and other indicators) raw coal, which seriously affects the output of the coal mill, resulting in insufficient capacity of the entire coal powder preparation, and at the same time, in order to meet the normal production of the blast furnace, the mill operation rate is almost 100%, without maintenance time, which brings certain safety risk to the normal production of the blast furnace; another part of enterprises, in order to reduce inventory and reduce financial pressure, raw coal is purchased back and directly used for pulverizing without time for stacking and drying operation in the raw coal yard, so that the conditions of the raw coal entering the mill, especially the moisture, are high, thereby affecting the output of the mill.In addition, environmental factors such as overcast and rainy days and open-air storage also make the moisture content of the raw coal entering the mill high, which is not conducive to the coal powder preparation production.

[0003] Through theoretical calculation and practice generation, it is shown that when the moisture content of raw coal is more than 10%, the mill coal powder output can be increased by 1.1-1.4% per 1% of moisture reduction, therefore, reducing the moisture in raw coal is very beneficial to coal powder preparation.

[0004] At present, few enterprises carry out preheating and dewatering treatment on raw coal, even if some do, the process is relatively complex, the investment and operation cost is high, and the overall economic benefit is not obvious, such as the use of drying furnace process, roller furnace process, electric heating process and the like in cement and other industries, but in the coal powder preparation process of blast furnace coal injection, no related preheating and dewatering process has been seen.Therefore, an online raw coal preheating device for coal powder preparation system is urgently needed to solve this problem. UTILITY MODEL CONTENT

[0005] The utility model aims at providing an online raw coal preheating device for coal powder preparation system to solve the problem of the need for a better preheating and dewatering scheme for raw coal of the coal powder preparation system.

[0006] In order to achieve the above object, the utility model provides the following technical scheme: A raw coal online preheating device of a pulverized coal preparation system, which comprises a raw coal bin, a steam main pipe and an outlet main pipe are arranged on the outer side of the raw coal bin, a plurality of steam branch pipes are connected between the steam main pipe and the outlet main pipe, each steam branch pipe penetrates into the inside of the raw coal bin at different heights of the raw coal bin, and penetrates out of the raw coal bin after arranging a heat exchange structure on the horizontal plane at the height, a steam branch pipe drain pipe is further connected to each steam branch pipe at the position of penetrating out of the raw coal bin, and a drain valve is connected to the outlet main pipe and each steam branch pipe drain pipe respectively; a steam branch pipe anti-collision device is fixedly arranged above each steam branch pipe in the inside of the raw coal bin, and is used for blocking the impact and friction of the raw coal on the steam branch pipe.

[0007] Preferably, the two ends of the steam branch pipe are respectively provided with a steam branch pipe inlet valve and a steam branch pipe outlet valve, and the steam main pipe is provided with a steam main pipe valve at the front end of all the steam branch pipes.

[0008] Preferably, the outlet main pipe and each steam branch pipe drain pipe are further respectively connected with a plurality of valve pieces, including a first drain valve, wherein the first drain valve on the steam branch pipe drain pipe is located at one end close to the connection of each steam branch pipe, and the first drain valve on the outlet main pipe is located at the rear end of all the steam branch pipes; the valve pieces further include a second drain valve located at the inlet end of each drain valve and a fourth drain valve located at the outlet end of the drain valve, a bypass pipeline is connected between the inlet end of the second drain valve and the outlet end of the fourth drain valve, and a third drain valve is arranged on the bypass pipeline.

[0009] Preferably, the heat exchange structure is a U-shaped coil pipe, which comprises a plurality of straight pipe segments arranged in parallel and connecting segments located at the end portions of the straight pipe segments, wherein the distances between each adjacent straight pipe segment are equal, and the connecting segments are alternately distributed at the two ends of the straight pipe segments.

[0010] Preferably, the steam branch pipe anti-collision device has two connected inclined surfaces, which are respectively located above the two sides of the steam branch pipe, and the inclined directions are from the upper middle portion of the steam branch pipe to the upper sides of the two sides downward.

[0011] Preferably, the steam branch pipe anti-collision device is fixedly connected with the inner wall of the raw coal bin, a plurality of hanging points are fixedly arranged at the lower end of the steam branch pipe anti-collision device, and are used for suspending and supporting the steam branch pipe.

[0012] Preferably, a raw coal bin top dust remover is fixedly arranged at the top of the raw coal bin, a dust removal fan is arranged in the raw coal bin top dust remover, and is used for discharging water vapor generated after the raw coal is heated.

[0013] Compared with the prior art, the utility model has the beneficial effects that:

[0014] 1. The coal powder preparation system raw coal online preheating device adopts a multi-layer heat exchange structure arrangement, effectively increasing the preheating effect on the raw coal, preheating and dehydrating the raw coal before entering the mill, which can improve the smoothness of the raw coal before entering the mill, reduce the occurrence of blockage, and on the other hand, due to the increase in the temperature of the raw coal, part of the water in the raw coal is evaporated, which can effectively reduce the moisture content of the raw coal, reduce the working load of the mill, reduce the equipment operation rate, improve the mill output level, effectively improve the mill output, and maximize the capacity of the equipment.

[0015] 2. The coal powder preparation system raw coal online preheating device has simple new or modified structure, little influence on the storage capacity of the raw coal bunker, low investment, good controllability during operation, and the preheating system discharges water vapor during operation, which is environmentally friendly. In addition, the preheating medium in the present application is steam, which can be saturated steam or supersaturated steam, and is a common medium in the plant area. Generally, the steam is abundant in enterprises, and can be fully utilized, which is an energy-saving measure. The water vapor in the raw coal preheating process is discharged outside the bunker through the dust collector arranged on the bunker top, which can effectively improve the working environment of the bunker top, and the raw coal bunker top dust collector can directly use the original dust removal equipment without additional investment. BRIEF DESCRIPTION OF DRAWINGS

[0016] Fig. 1 It is a three-dimensional structure schematic diagram of the present application, only two layers of heat exchange structure are drawn to illustrate;

[0017] Fig. 2 It is a cross-sectional structure schematic diagram of the steam branch pipe anti-collision device;

[0018] Fig. 3 It is a schematic diagram of the position relationship between the steam branch pipe anti-collision device and the steam branch pipe.

[0019] In the figure: 1, steam main pipe; 1.1, steam branch pipe inlet valve; 1.2, steam branch pipe outlet valve; 1.3, steam branch pipe; 1.4.1, first drain valve; 1.4.2, second drain valve; 1.4.3, third drain valve; 1.4.4, fourth drain valve; 1.5, steam branch pipe drain pipe; 1.6, steam branch pipe anti-collision device; 2, steam main pipe valve; 3.1, drain valve; 4, outlet main pipe; 6, raw coal bunker top dust collector. DETAILED DESCRIPTION

[0020] Reference Figs. 1 to 3The application discloses a raw coal online preheating device of a pulverized coal preparation system, which comprises a raw coal bin, an outer side of the raw coal bin is provided with a steam main pipe 1 and an outlet main pipe 4, a plurality of steam branch pipes 1.3 are connected between the steam main pipe 1 and the outlet main pipe 4, each steam branch pipe 1.3 penetrates into the inside of the raw coal bin at different heights, and after being arranged with a heat exchange structure on the horizontal plane at the height, the steam branch pipe 1.3 penetrates out of the raw coal bin, each steam branch pipe 1.3 is further connected with a steam branch pipe drainage pipe 1.5 at the position penetrating out of the raw coal bin, the outlet main pipe 4 and each steam branch pipe drainage pipe 1.5 are respectively connected with a drain valve 3.1, which is used for draining the water condensed in the pipeline after heat exchange; in view of the problem that the steam pipeline in the raw coal bin is directly pressed and rubbed by the coal seam gravity, the pipeline is deformed and cracked, and finally the steam leaks into the raw coal bin, a steam branch pipe anti-collision device 1.6 is fixedly arranged above each steam branch pipe 1.3 in the inside of the raw coal bin, which is used for blocking the impact and friction of the raw coal on the steam branch pipe 1.3. In the above structure, the height direction spacing between adjacent heat exchange structures can be set according to the actual situation without affecting the downward movement of the raw coal.

[0021] In addition, the steam main pipe 1 can be connected with a steam main pipe in a factory area, and the outlet main pipe 4 and the steam branch pipe drainage pipe 1.5 can be connected with a drainage ditch around a factory building; a belt conveyor is arranged at a raw coal inlet at an upper end of the raw coal bin to continuously convey the raw coal into the raw coal bin.

[0022] Optionally, the steam branch pipe 1.3 is respectively provided with a steam branch pipe inlet valve 1.1 and a steam branch pipe outlet valve 1.2 at two ends, whether each layer of steam pipeline is connected with the preheating system can be adjusted according to the actual needs on site; the steam main pipe 1 is provided with a steam main pipe valve 2 at the front end of all the steam branch pipes 1.3, which is used for selecting whether to start the steam preheating system and daily maintenance according to the actual situation of the raw coal bin.

[0023] In order to ensure drainage and facilitate valve maintenance, the outlet main pipe 4 and each steam branch pipe drainage pipe 1.5 are further respectively connected with a plurality of valve components, including a first drain valve 1.4.1, wherein the first drain valve 1.4.1 on the steam branch pipe drainage pipe 1.5 is located at one end close to the connection of each steam branch pipe drainage pipe 1.5 and each steam branch pipe 1.3, and the first drain valve 1.4.1 on the outlet main pipe 4 is located at the rear end of all the steam branch pipes 1.3; the valve components further include a second drain valve 1.4.2 located at the inlet end of each drain valve 3.1 and a fourth drain valve 1.4.4 located at the outlet end of the drain valve 3.1, a bypass pipeline is connected between the inlet end of the second drain valve 1.4.2 and the outlet end of the fourth drain valve 1.4.4, and the bypass pipeline is provided with a third drain valve 1.4.3, in normal working condition, the third drain valve 1.4.3 is closed, and the first drain valve 1.4.1, the second drain valve 1.4.2 and the fourth drain valve 1.4.4 are opened.

[0024] In a preferred embodiment, the heat exchange structure is a U-shaped coil pipe, which comprises a plurality of straight pipe sections arranged in parallel and connecting sections at the ends of the straight pipe sections, wherein the distance between each adjacent straight pipe section is equal (as shown in Fig. Fig. 1 During the process of the steam circulating in the coal bunker through the steam branch pipe 1.3, the heat of the steam is conducted to the raw coal around the steam branch pipe 1.3 through the pipe wall of the steam branch pipe 1.3 to heat the raw coal, and then the temperature of the water carried by the raw coal is increased, and part of the water is evaporated due to the temperature increase, thereby reducing the physical water content of the raw coal.

[0025] In a preferred embodiment, the steam branch pipe anti-collision device 1.6 has two connected inclined surfaces, which are respectively located above the two sides of the steam branch pipe 1.3 and are inclined downward from the upper middle part of the steam branch pipe 1.3 to the upper sides of the two sides, which can simultaneously avoid the accumulation of raw coal above the steam branch pipe 1.3 and facilitate the falling of the raw coal.

[0026] The steam branch pipe anti-collision device 1.6 can be fixedly connected with the inner wall of the raw coal bunker, and a plurality of hanging points can be further fixedly arranged at the lower end of the steam branch pipe anti-collision device 1.6 for suspending and supporting the steam branch pipe 1.3.

[0027] In order to discharge the water vapor evaporated from the raw coal due to the temperature increase, a raw coal bunker top dust remover 6 is fixedly arranged at the top of the raw coal bunker, and a dust removal fan is arranged in the raw coal bunker top dust remover 6, which can use the suction force to discharge the steam escaping from the raw coal bunker, so as to avoid the condensation of the steam into water in the raw coal bunker and improve the raw coal preheating and dehydration effect.

[0028] All the valve parts can be manually, electrically or driven according to the actual needs on the site. In addition, the shape of the raw coal bunker is not limited to the square bunker shown in Fig. 1 , but can also be a round bunker or other forms, and the structural form can be a steel structure or a concrete structure, Fig. 1 The connecting sections of the heat exchange structure do not have to pass through the raw coal bunker, especially in the concrete structure.

[0029] The above is only a preferred embodiment of the present application, but the protection scope of the present application is not limited to this, any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be limited by the protection scope defined in the claims.

[0030] The parts not described in the present application are the known technology of the person skilled in the art.

Claims

1. An online preheating device for raw coal in a pulverized coal preparation system, characterized in that: The original coal bunker is provided with a steam main pipe (1) and an outlet main pipe (4) outside, a plurality of steam branch pipes (1.3) are connected between the steam main pipe (1) and the outlet main pipe (4), each steam branch pipe (1.3) penetrates into the inside of the original coal bunker at different heights, and after arranging a heat exchange structure on the horizontal plane at the height, it penetrates out of the original coal bunker, each steam branch pipe (1.3) is further connected with a steam branch pipe drain pipe (1.5) at the position penetrating out of the original coal bunker, and the outlet main pipe (4) and each steam branch pipe drain pipe (1.5) are respectively connected with a drain valve (3.1); a steam branch pipe anti-collision device (1.6) is fixedly arranged inside the original coal bunker above each steam branch pipe (1.3) and used for blocking the impact and friction of the original coal on the steam branch pipe (1.3).

2. The online raw coal preheating device of a pulverized coal preparation system according to claim 1, characterized in that: The steam branch pipe (1.3) is respectively provided with a steam branch pipe inlet valve (1.1) and a steam branch pipe outlet valve (1.2) at two ends, and the steam main pipe (1) is provided with a steam main pipe valve (2) at the front end of all steam branch pipes (1.3).

3. The online raw coal preheating device of a pulverized coal preparation system according to claim 1, characterized in that: The outlet main pipe (4) and each steam branch pipe drain pipe (1.5) are further respectively connected with a plurality of valve components, including a first drain valve (1.4.1), wherein the first drain valve (1.4.1) on the steam branch pipe drain pipe (1.5) is located close to the end of each steam branch pipe drain pipe (1.5) connected with each steam branch pipe (1.3), and the first drain valve (1.4.1) on the outlet main pipe (4) is located at the rear end of all steam branch pipes (1.3); the valve components further include a second drain valve (1.4.2) located at the inlet end of each drain valve (3.1) and a fourth drain valve (1.4.4) located at the outlet end of the drain valve (3.1), and a bypass pipeline is connected between the inlet end of the second drain valve (1.4.2) and the outlet end of the fourth drain valve (1.4.4), and a third drain valve (1.4.3) is arranged on the bypass pipeline.

4. The online raw coal preheating device of a pulverized coal preparation system according to claim 1, characterized in that: The heat exchange structure is a U-shaped coil pipe, which includes a plurality of straight pipe segments arranged in parallel and connecting segments located at the ends of the straight pipe segments, wherein the distances between each adjacent straight pipe segment are equal, and the connecting segments are alternately distributed at the two ends of the straight pipe segments.

5. The online raw coal preheating device of a pulverized coal preparation system according to claim 1, characterized in that: The steam branch pipe anti-collision device (1.6) has two connected inclined surfaces, which are located above the two sides of the steam branch pipe (1.3) respectively, and the inclined directions are from the upper middle part of the steam branch pipe (1.3) to the upper sides of the two sides downward.

6. The online raw coal preheating device of a pulverized coal preparation system according to claim 1, characterized in that: The steam branch pipe anti-collision device (1.6) is fixedly connected with the inner wall of the original coal bunker, a plurality of hanging points are fixedly arranged at the lower end of the steam branch pipe anti-collision device (1.6) at intervals, and are used for suspending and supporting the steam branch pipe (1.3).

7. The online raw coal preheating device of a pulverized coal preparation system according to claim 1, characterized in that: The top of the original coal bunker is fixedly provided with an original coal bunker top dust remover (6), which is provided with a dust removal fan inside and is used for discharging water vapor generated after the original coal is heated.

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