A new type of wear-resistant coal feeding device for CFB boiler

Abstract

The present invention discloses a new type of wear-resistant coal feeding device for a CFB boiler, comprising a coal feeding channel and a coal spreading air channel arranged on the side wall of the furnace, the coal feeding channel is connected to the end of the coal spreading air channel, the upper end of the coal feeding channel is connected to the furnace coal channel, a wear-resistant stainless steel air guide plate is installed at the coal feeding port at the bottom of the coal spreading air channel, the angle between the wear-resistant stainless steel air guide plate and the horizontal plane is 15 degrees, the right end face of the wear-resistant stainless steel air guide plate is connected to an anti-wear plate, the angle between the wear-resistant plate and the horizontal plane is 45 degrees, and a plurality of flow guide and anti-wear blocks are arranged on the anti-wear plate. The new type of wear-resistant coal feeding device for a CFB boiler provided by the present invention can solve the problem that the coal feeding port of the currently in-service large-scale circulating fluidized bed unit is seriously worn, which affects the long-term operation of the unit.

Description

Technical Field

[0001] The invention relates to the technical field of coal feeding ports of circulating fluidized bed units, and in particular to a novel wear-resistant coal feeding device for a CFB boiler. Background Art

[0002] Circulating fluidized bed boilers have high combustion adaptability and have great advantages in the combustion of inferior coal, urban sludge and garbage treatment, and coal sludge disposal. As a highly efficient and clean coal combustion technology, the installed capacity of large-scale circulating fluidized bed units in China is increasing year by year. However, since the coal particle size is coarser than that of pulverized coal furnaces, the wear problem of the coal feed port is more prominent. The coal feed port is one of the most important equipment in the daily operation of the circulating fluidized bed unit, and its operating status directly determines whether the circulating fluidized bed unit can operate for a long period of time. In order to meet this requirement, it is necessary to make comprehensive improvements to the coal feed port. Summary of the invention

[0003] In order to solve the shortcomings and deficiencies of the prior art, a new wear-resistant coal feeding device for a CFB boiler is provided, thereby solving the problem that the coal feeding port of the currently in-service large-scale circulating fluidized bed unit is seriously worn, affecting the long-term operation of the unit.

[0004] A novel anti-wear coal feeding device for a CFB boiler is provided to achieve the purpose of the present invention, comprising a coal feeding channel and a coal spreading air channel arranged on the side wall of the furnace, the coal feeding channel is connected to the end of the coal spreading air channel, the upper end of the coal feeding channel is connected to the furnace coal channel, a wear-resistant stainless steel air guide plate is installed at the coal feeding port at the bottom of the coal spreading air channel, the angle between the wear-resistant stainless steel air guide plate and the horizontal plane is 15 degrees, the right end face of the wear-resistant stainless steel air guide plate is connected to an anti-wear plate, the angle between the wear-resistant plate and the horizontal plane is 45 degrees, and a plurality of guide and anti-wear blocks are arranged on the anti-wear plate; the guide and anti-wear blocks include tangential guide blocks and rectangular anti-wear strips, and a plurality of the tangential guide blocks and the rectangular anti-wear strips are arranged, and the plurality of the tangential guide blocks are arranged in two rows in parallel from top to bottom on the anti-wear plate, and the two rows of tangential guide blocks are arranged at intervals to form an anti-wear guide and diversion layer; the rectangular anti-wear strips are arranged in three rows in parallel from top to bottom on the anti-wear plate to form a self-anti-wear layer.

[0005] As a further improvement, the cross section of the upper end surface of the tangential drainage block is a quarter arc, and its vertical end is perpendicular to the wear plate.

[0006] As a further improvement, the upper and lower rows of the anti-wear guide and diversion layer are respectively provided with four tangential drainage blocks and five tangential drainage blocks, so that the impacting coal flow passes through the tangential drainage blocks and is divided into 9 small-flow coal flows.

[0007] As a further improvement, the anti-wear flow guiding and diverting layer and the self-anti-wear layer are arranged in a fan shape with a narrow top and a wide bottom.

[0008] The beneficial effects of the present invention are:

[0009] Compared with the prior art, the present invention provides a new type of wear-resistant coal feeding device for CFB boilers, which upgrades the original ordinary steel plate at the coal feeding port to wear-resistant stainless steel material, which has the advantages of good toughness and strong thermoplasticity. It is more wear-resistant than conventional steel materials; by installing a wear-resistant stainless steel air guide plate at the place where the coal-spreading wind enters the coal feeding port, the material of which is wear-resistant stainless steel, and the angle between it and the horizontal plane is 15 degrees, and the requirement is that it does not affect the coal-spreading, the wind direction of the coal-spreading wind entering the coal feeding port can be appropriately adjusted to prevent the coal particles from washing into the upper area of ​​the coal feeding port. After changing the wind direction of the coal-spreading wind, the coal particles entering the furnace distribution area will be slightly lifted upward, which prevents most of the coal particles from falling on the anti-wear plate, so that more coal particles are brought into the furnace; for a small number of coal particles that still fall on the anti-wear plate area, the anti-wear plate is worn. According to previous wear experience and rules, it is not necessary to cover all the guide anti-wear blocks on the anti-wear plate, and only install them in the severely worn parts. The guide anti-wear blocks are used in combination with different anti-wear mechanisms to achieve the anti-wear effect.

[0010] The anti-wear guide block is composed of an anti-wear guide diversion layer and a self-wear protection layer, which are arranged in a fan shape with narrow upper part and wide lower part. The anti-wear guide diversion layer is composed of upper and lower rows of tangential guide blocks, and adopts the tangential guide anti-wear principle.

[0011] This production has three functions: anti-wear, flow diversion, and flow separation.

[0012] 1. Anti-wear: The coal particles entering the furnace rush toward the tangential drainage block at an angle of 60° to the horizontal. Due to the curvature design of the tangential drainage block, the particles enter the anti-wear plate tangentially. According to the force analysis principle, the particles entering tangentially are subject to the least resistance. Conversely, the impact force on the anti-wear plate is the smallest. After passing through the curved tangential drainage block, the particles are thrown a second time, which makes the anti-wear plate well protected and also makes the fluidization effect on the anti-wear plate of the circulating fluidized bed boiler better.

[0013] 2. Diversion: The particle size of the materials entering the circulating fluidized bed boiler is basically all solid particles less than 10mm. The tangential diversion block is 5mm high, with an arc radius of 5mm and a diameter of 10mm, which can be used to divert all the material particles entering the boiler.

[0014] 3. Diversion: There are 4 tangential diversion blocks installed at equal intervals in the first row, which divide the impacted coal flow into 9 small flows through the tangential diversion blocks (4 of which are tangentially passed through the 4 tangential diversion blocks in the first row, and the remaining 5 small flows enter the second row), which disperses the impact of the coal flow and plays a role in diversion and wear prevention. The second row of tangential diversion blocks is a good supplement to the first row, diverting the 5 small flows of particles diverted from the first row.

[0015] The self-wear-proof layer is composed of three rows of rectangular anti-wear strips arranged in parallel from top to bottom. The principle is as follows: due to the tangential drainage effect of the anti-wear guide and diversion layer, most of the particles are diverted into the furnace. The coal particles entering the furnace have a relatively low speed when they rush to the self-wear-proof layer, and are deposited between the angles of the rectangular anti-wear strips and the anti-wear plates, forming a natural anti-wear belt. When other subsequent particles impact the anti-wear belt, they first impact the particles remaining in the angle and do not directly wash the anti-wear bottom plate, thus achieving a self-wear-proof effect.

[0016] The invention provides a novel wear-resistant coal feeding device for a CFB boiler, which can solve the problem that the coal feeding port of a currently in-service large-scale circulating fluidized bed unit is seriously worn, thus affecting the long-term operation of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings, wherein:

[0018] Figure 1 It is a structural schematic diagram of an existing coal feeding port;

[0019] Figure 2 It is a schematic diagram of the distribution of coal particles at the existing coal feeding port;

[0020] Figure 3 It is a schematic diagram of the principle structure of the present invention;

[0021] Figure 4 for Figure 3 An enlarged view of the coal feed port;

[0022] Figure 5 It is a schematic structural diagram of the wear-resistant plate of the present invention;

[0023] Figure 6 It is a schematic diagram of the anti-wear principle of the present invention. DETAILED DESCRIPTION

[0024] like Figure 1-Figure 6As shown, a new type of wear-resistant coal feeding device for a CFB boiler provided by the present invention includes a coal feeding channel 1 and a coal spreading air channel 2 arranged on the side wall of a furnace 200, the coal feeding channel 1 is connected to the ends of the coal spreading air channel 2, the upper end of the coal feeding channel 1 is connected to a furnace coal inlet channel 3, a wear-resistant stainless steel air guide plate 4 is installed at the coal feeding port 100 at the bottom of the coal spreading air channel 2, the angle between the wear-resistant stainless steel air guide plate 4 and the horizontal plane is 15 degrees, the right end face of the wear-resistant stainless steel air guide plate 4 is connected to an anti-wear plate 5, the angle between the wear-resistant stainless steel air guide plate 5 and the horizontal plane is 45 degrees, a plurality of guide and anti-wear blocks are arranged on the anti-wear plate 5, the guide and anti-wear blocks include tangential guide blocks 61 and rectangular anti-wear strips 62, and a plurality of tangential guide blocks 61 and rectangular anti-wear strips 62 are arranged. Among them, a plurality of tangential drainage blocks 61 are arranged in two rows in parallel from top to bottom on the anti-wear plate, and the two rows of tangential drainage blocks 61 are arranged at intervals to form an anti-wear diversion and diversion layer; the cross-section of the upper end face of the tangential drainage block 61 is a quarter arc, and its vertical end is perpendicular to the anti-wear plate. The upper and lower rows of the anti-wear diversion and diversion layer are respectively provided with four tangential drainage blocks 61 and five tangential drainage blocks 61, so that the impacting coal flow passes through the tangential drainage blocks 61 and is divided into 9 small-flow coal flows. Rectangular anti-wear strips 62 are arranged in three rows in parallel from top to bottom on the anti-wear plate to form a self-anti-wear layer. The anti-wear diversion and diversion layer and the self-anti-wear layer are arranged in a fan-shaped shape with a narrow top and a wide bottom.

[0025] Specifically, for the coal feeding port size of 900mm in length and 810mm in width, in the technical solution, the cross-section of the wear-resistant stainless steel air guide plate 4 is an isosceles triangle with a waist of 58mm and a base of 30mm. The length of the anti-wear plate 5 is 900mm, the width is 480mm, and the angle with the horizontal ground is 45°. There are 4 upward tangential drainage blocks 61 of the anti-wear diversion and diversion layer, and the 4 tangential drainage blocks 61 are 56mm apart. Each block is 80mm long and 5mm high. The curvature of the upper surface of the tangential drainage block 61 is 1 / 4 of a circular arc with a radius of 5mm. There are 5 downward tangential drainage blocks 61 of the anti-wear diversion and diversion layer, and the 5 tangential drainage blocks 61 are 80mm apart. Each block is 56mm long and 5mm high. The curvature of the upper surface of the tangential drainage block 61 is 1 / 4 of a circular arc with a radius of 5mm.

[0026] The dimensions of the three rectangular anti-wear strips 62 from top to bottom of the anti-wear layer are: length 700mm, height 10mm, thickness 3mm; length 750mm, height 10mm, thickness 3mm; length 800mm, height 10mm, thickness 3mm. The rectangular anti-wear strips 62 are all vertically installed on the anti-wear plate.

[0027] The above embodiments are not limited to the technical solutions of the embodiments themselves, and the embodiments can be combined with each other to form new embodiments. The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Any modification or equivalent replacement that does not deviate from the spirit and scope of the present invention shall be included in the scope of the technical solutions of the present invention.

Claims

1. A new type of anti-wear coal feeding device for CFB boiler, characterized by: The invention comprises a coal feeding channel and a coal spreading air channel arranged on the left side wall of the furnace, the coal feeding channel is connected with the end of the coal spreading air channel, the upper end of the coal feeding channel is connected with the furnace coal inlet channel, and a wear-resistant stainless steel air guide plate is installed at the coal feeding port at the bottom of the coal spreading air channel, the angle between the wear-resistant stainless steel air guide plate and the horizontal plane is 15 degrees, the right end face of the wear-resistant stainless steel air guide plate is connected with an anti-wear plate, the angle between the anti-wear plate and the horizontal plane is 45 degrees, and a plurality of guide and anti-wear blocks are arranged on the anti-wear plate; the guide and anti-wear blocks comprise tangential drainage blocks and rectangular anti-wear strips, and a plurality of the tangential drainage blocks and the rectangular anti-wear strips are both arranged, and the plurality of the tangential drainage blocks are arranged in two rows in parallel from top to bottom on the anti-wear plate, and the two rows of tangential drainage blocks are arranged at intervals to form an anti-wear guide and diversion layer; the rectangular anti-wear strips are arranged in three rows in parallel from top to bottom on the anti-wear plate to form a self-anti-wear layer, and the anti-wear guide and diversion layer is located above the self-anti-wear layer.

2. The novel anti-wear coal feeding device for CFB boiler according to claim 1 is characterized by: The cross section of the upper end surface of the tangential drainage block is a quarter arc, and the vertical end thereof is perpendicular to the anti-wear plate.

3. The novel anti-wear coal feeding device for CFB boiler according to claim 2 is characterized by: The upper and lower rows of the anti-wear guide and diversion layer are respectively provided with four tangential diversion blocks and five tangential diversion blocks, so that the impacted coal flow passes through the tangential diversion blocks and is divided into 9 small-flow coal flows.

4. The novel anti-wear coal feeding device for CFB boiler according to claim 1 is characterized by: The anti-wear flow guiding and diverting layer and the self-wear anti-wear layer are arranged in a fan shape with a narrow top and a wide bottom.

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