Multi-coal blending combustion raw coal bunker

Abstract

The utility model relates to the technical field of raw coal blending combustion equipment, in particular to a multi-coal blending combustion raw coal bunker. Comprising a coal feeding belt, a coal feeding bin and a coal feeder, a partition plate for dividing a working bin in the coal feeding bin into two coal storage bins is arranged in the coal feeding bin; the coal feeding belt is communicated with feeding ports of the two coal storage bunkers and conveys two kinds of raw coal into the two coal storage bunkers respectively. A coal blending assembly used for blending raw coal in the two coal storage bunkers according to production requirements is arranged at an outlet of each coal storage bunker. The coal feeder is in butt joint with the coal blending assembly, and raw coal blended by the coal blending assembly is conveyed into the coal mill. The raw coal bunker not only can mix different raw coal according to production requirements, but also is simple in structure and stable in operation.

Description

Technical Field

[0001] The utility model relates to the technical field of raw coal co-firing equipment, in particular to a raw coal bunker for co-firing multiple coal types. Background Art

[0002] With the sharp rise in energy prices, the price of coal for combustion has also increased significantly. As a major coal consumer, the coal consumption cost is the largest cost of coal-fired power generation units. Therefore, selecting more economical coal types is the top priority for coal-fired power plants to reduce costs and increase efficiency. The price differences between different coal types are extremely large. Usually, coal types with lower calorific values have higher cost performance. Coal-fired power plants often choose coal with higher cost performance. For example, coal with a low calorific value is not the designed coal type and needs to be co-fired. There are also N many types of coal with low calorific values. Calorific value is only one of the important parameters for measuring coal quality, and coals with the same calorific value per unit cannot be regarded as the same type of coal. However, the combustion properties of different coal varieties vary greatly. The calorific value, volatile matter, grindability coefficient, ash content, sulfur content, and caking temperature of ash slag of different coal types are all different. These parameters not only affect the safe operation of the boiler but also affect the load-carrying capacity of the unit. To meet the requirements of combustion safety and economy, different coal types must be co-fired.

[0003] The traditional co-firing method is to perform pre-mixing, that is, two or several types of coal are pre-mixed in proportion and then incorporated into one coal bunker or several coal bunkers. That is, several types of coal are first mixed and then the mixed coal is sent into certain coal bunkers. For safety reasons, not all coal bunkers of a boiler will choose this pre-mixed coal. This pre-mixing method has the following problems:

[0004] The mixing process is complicated, consuming a large amount of manpower and material resources, and it is difficult to achieve uniform blending. For traditional coal blending (pre-mixing), generally, large machinery is used in the coal storage yard to mix two or more types of coal and then send it to the coal bunker. This most primitive blending method first requires a large coal yard, second requires large machinery and labor, and the blending is extremely uneven.

[0005] Another co-firing method is: in the coal conveying link, two sets of coal conveying belts are first used to convey two types of coal simultaneously, and finally fall on one conveying belt and continuously sent to the coal bunker. This blending method is evenly mixed and is also slightly labor-saving, but it requires the construction of an additional set of coal conveying systems, occupies a large area, has a long mixing time and complex control, and most power plants do not have space to build it.

[0006] After the above two co-firing methods blend two or more types of coal, in fact, the two types of coal become "another type of coal", so its composition is re-fixed. When incorporated into the coal bunker for co-firing, it only meets the requirements of safe co-firing, and the economy and flexibility of co-firing are restricted.

[0007] The load regulation capacity of the pulverizing system is limited. When the unit load curve changes significantly, the only option is to passively start and stop the pulverizing system. When the electrical load increases, more pulverizing systems need to be started; when the electrical load decreases, the pulverizing system needs to be reduced to meet the demand for large load changes.

[0008] This co-firing method is severely restricted. First, when the pulverizing system where the coal bunker for blending is located is forced to stop operating, the actual co-firing rate of that coal bunker is "0". Second, the coal types cannot be quickly switched. For example, when the power generation curve requires a load reduction, the best way is to keep the mills running and immediately switch the coal type in the operating mill to a coal type with a lower calorific value (the coal type to be co-fired), and the coal type with a lower calorific value has a higher cost-effective ratio. Conversely, when the power generation curve increases, immediately burn coal with a high calorific value to quickly peak power generation and make money. However, in reality, due to the large capacity of the coal bunker and the presence of stockpiled coal, it is impossible to achieve an immediate switch. Conversely, when the power generation load increases significantly and it is impossible to quickly switch to a coal type with a high calorific value, only multiple pulverizing systems can be started to peak load. Therefore, the operation is extremely complicated, and starting and stopping the pulverizing system frequently disturbs combustion, seriously affecting the economy and safety of the boiler; moreover, using the start and stop of the pulverizing system to increase and decrease the load has extremely poor timeliness. If the real-time load curve of the generator set exceeds the command curve value issued by the dispatching, the generator set will be deducted points and evaluated.

[0009] In addition, for the existing co-blending methods of the same type, the operation requires the use of two gate plates. The installation positions of these two gate plates require a large space and the adjustment is complicated. There may be a risk of coal feeding interruption for the coal feeder. Therefore, it is urgent to solve this problem.

[0010] The above content is only used to assist in understanding the technical solution of the present invention and does not represent an admission that the above content is the closest prior art. Summary of the Invention

[0011] The technical problem to be solved by the present invention is to provide a raw coal bunker for multi-coal co-firing, which can not only blend different raw coals according to production requirements, but also has a simple structure and stable operation.

[0012] To achieve the above object, the technical solution of the present invention is realized as follows: A raw coal bunker for multi-coal co-firing includes a coal feeding belt, a coal feeding bunker, and a coal feeder; a partition is provided in the coal feeding bunker to divide the working bin inside the coal feeding bunker into two coal storage bins; the coal feeding belt is connected to the feeding ports of the two coal storage bins and transports two kinds of raw coals to the two coal storage bins respectively; a coal blending component is provided at the outlet of the coal storage bin for blending the raw coals in the two coal storage bins according to production requirements; the coal feeder is docked with the coal blending component and transports the raw coal blended by the coal blending component to the coal mill.

[0013] Preferably, a pressure relief hole communicating the two coal storage bins is provided on the partition.

[0014] Preferably, the coal feeding bin is funnel-shaped; the partition plate is located on the center line of the coal feeding bin, and the top of the partition plate is flush with the top of the coal feeding bin. The bottom of the partition plate divides the discharge port of the coal feeding bin into two equal parts, forming the discharge ports of two coal storage bins; the coal blending component includes a driving part and a blocking part; the blocking part is used to block the discharge ports of the two coal storage bins; the driving part is installed at the bottom of the partition plate and is connected to the blocking part, and drives the blocking parts at the discharge ports of the two coal storage bins to move alternately according to production requirements.

[0015] Preferably, the blocking part includes two baffle plates; both of the two baffle plates are connected to the driving part and can respectively block the discharge ports of the two coal storage bins under the drive of the driving part.

[0016] Preferably, the driving part includes a driving motor and a motor rotating shaft; the motor rotating shaft is connected to both of the two baffle plates, and the motor rotating shaft drives the two baffle plates to swing under the drive of the driving motor.

[0017] Preferably, it further includes a first coal bin outlet gate valve, a first driving motor, a second coal bin outlet gate valve and a second driving motor arranged at the discharge port of the coal feeding bin; the first coal bin outlet gate valve and the second coal bin outlet gate valve are used to block the discharge port of the coal feeding bin, and the first coal bin outlet gate valve, the second coal bin outlet gate valve and the baffle plate jointly enclose a mixing bin at the discharge port of the coal feeding bin; the first driving motor is used to drive the first coal bin outlet gate valve to move; the second driving motor is used to drive the second coal bin outlet gate valve to move.

[0018] Preferably, it further includes air cannons; there are at least two air cannons, which are respectively arranged on both sides of the coal feeding bin and are used to provide an air flow that promotes the falling of raw coal in the two working bins of the coal feeding bin.

[0019] Preferably, a handle for rotating the cylindrical sleeve is provided on the cylindrical sleeve.

[0020] The beneficial effects of the present utility model are embodied in:

[0021] (1) The raw coal bin provided by the present utility model can be divided into two left and right coal storage bins, and each coal storage bin can be loaded with coal separately. Therefore, the raw coal bin can be used to load two kinds of coal at the same time. By adjusting the opening mode of the conversion baffle plate, either a certain kind of coal can be used alone, or two kinds of coal can be mixed at different ratios at the same time, so as to increase the blending methods.

[0022] (2) The raw coal bin provided by the present utility model is simple and fast to switch the blending of two kinds of coal. It only needs to control the switching of the conversion baffle plate to complete, without having to wait because of the stock coal in the raw coal bin. Moreover, the blending of coal types is convenient, time-saving, labor-saving and cost-saving. There is no need to pre-mix and blend coal types in advance, no need to consume a large amount of manpower and material resources for pre-mixing, and the problem of uneven blending can be effectively solved. Brief Description of the Drawings

[0023] Figure 1 is a schematic structural view of the present utility model;

[0024] Figure 2 is a partial structural view of the partition of the present utility model;

[0025] Figure 3 is a schematic structural view of the coal blending component of the present utility model;

[0026] Figure 4 is a side view of the motor shaft and the baffle of the present utility model.

[0027] Description of the Reference Numerals:

[0028] 10, coal feeding belt; 20, coal supply bin; 21, partition; 211, pressure relief hole; 22, air cannon;

[0029] 23, baffle; 24, motor shaft; 25, first coal bin outlet gate; 251, first driving motor;

[0030] 26, second coal bin outlet gate; 261, second driving motor; 30, coal feeder. Detailed Description of the Embodiments

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present utility model with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Without conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0032] Embodiment

[0033] Refer to Figures 1-4 as shown:

[0034] The present utility model provides a multi-coal-type blended raw coal bin, including: a coal feeding belt 10, a coal supply bin 20, and a coal feeder 30.

[0035] A partition 21 for dividing the working bin inside the coal supply bin 20 into two coal storage bins is provided in the coal supply bin 20; a pressure relief hole 211 communicating the two coal storage bins is provided on the partition 21. The coal feeding belt 10 is communicated with the feeding ports of the two coal storage bins and conveys two kinds of raw coal to the two coal storage bins respectively; an outlet of the coal storage bin is provided with a coal blending component for blending the raw coal in the two coal storage bins according to production requirements; the coal feeder 30 is docked with the coal blending component and conveys the raw coal blended by the coal blending component to the coal mill.

[0036] After the partition 21 is set in the middle of the coal bunker 20, it is equivalent to dividing the interior of the coal bunker 20 into two, which results in a smaller capacity of a single coal storage bin and a smaller transverse cross-section of a single coal storage bin; when loading coal, the raw coal falls from the coal loading belt 10, which will stir up air waves in the coal storage bin. If a solid partition 21 is used, when loading coal, the air waves will rush out from the bottom of the coal storage bin to the top, stirring up coal dust, seriously polluting the environment and causing safety hazards. When a partition 21 with a pressure relief hole 211 is used, part of the gas can be relieved to the adjacent coal storage bin through the pressure relief hole 211; when the adjacent coal storage bin also has coal, firstly, because there is a gap between the coal, part of the gas can also be relieved; secondly, because the pressure relief hole 211 on the partition 21 increases the friction coefficient of the bin wall, it can also effectively reduce the upward rushing speed of the gas, thereby achieving the purpose of suppressing the upward rushing speed of the air wave.

[0037] In practice, the coal bunker 20 is designed in a funnel shape. A partition 21 is located at the centerline of the bunker 20, with its top flush with the top. The bottom of the partition 21 divides the discharge port of the bunker 20 into two equal parts, forming two coal storage bin discharge ports. The coal blending assembly includes a drive unit and a sealing unit. The sealing unit is used to seal the discharge ports of the two coal storage bins. The drive unit is mounted at the bottom of the partition 21 and connected to the sealing unit, driving the sealing units at the discharge ports of the two coal storage bins in turn according to production needs.

[0038] The blocking portion includes two baffles 23; the two baffles 23 are both connected to the driving portion, and can respectively block the discharge ports of the two coal storage bins under the drive of the driving portion.

[0039] The driving unit includes a driving motor and a motor shaft 24. The motor shaft 24 is connected to both baffles 23, and the motor shaft 24 drives the two baffles 23 to swing under the drive of the driving motor.

[0040] It also includes a first coal bin outlet gate 25, a first drive motor 251, a second coal bin outlet gate 26 and a second drive motor 261 arranged at the discharge port of the coal feeding bin 20; the first coal bin outlet gate 25 and the second coal bin outlet gate 26 are used to block the discharge port of the coal feeding bin 20, and the first coal bin outlet gate 25, the second coal bin outlet gate 26 and the baffle 23 together enclose the mixed material bin at the discharge port of the coal feeding bin 20; the first drive motor 251 is used to drive the first coal bin outlet gate 25 to move; the second drive motor 261 is used to drive the second coal bin outlet gate 26 to move.

[0041] In specific applications, the baffle 23 is a single-width structure with the opening facing downward, and can be rotated by the motor shaft 24; the motor shaft 24 is horizontally consistent with the bottom of the partition 21; it is driven by a drive motor and can be rotated up to 180°. The drive motor accepts DCS command control and can stop at any position within the limit.

[0042] The working principle of the baffle 23 is as follows: When the production requirement is to mix and burn the coal in two coal storage bins, the motor shaft 24 drives the two baffles 23 to both vertically downward, and the raw coal in the two coal storage bins can be mixed and burned in a 1:1 ratio. When the mixing ratio of the raw coal in one of the coal storage bins is required, only the motor shaft 24 needs to drive one baffle 23 to close the outlet of this coal storage bin. If one of the two coal storage bins is closed by the two baffles 23, the other coal storage bin can operate independently, and vice versa.

[0043] The advantage of using the baffle 23 that can be adjusted and converted is that it can not only ensure that there is always coal falling, that is, one side of the baffle 23 is always open. It will not be like the traditional method of using two gate valves on the left and right, where both gate valves may be closed by mistake and the coal supply is cut off; moreover, the mixing adjustment of coal types is simple and convenient, with one-key adjustment, simple and intuitive, abandoning the traditional method of using two gate valves to cooperate with each other to adjust the mixing ratio. In addition, the structure is simple, only one baffle 23 plus a driving motor; and the baffle 23 is installed at the outlet of the coal feeding bin 20, without the traditional gate valve extension mechanism, covering a small area, so the requirement for the installation space is low.

[0044] It also includes air cannons 22; there are at least two air cannons 22, which are respectively arranged on both sides of the coal feeding bin 20 and are used to provide an air flow that promotes the falling of the raw coal in the two working bins of the coal feeding bin 20.

[0045] In specific applications, when the coal falling in the coal storage bin is not smooth, the air cannons 22 can be started, and the air flow generated by the sudden release of compressed air is used to impact and vibrate the coal layer, so as to loosen and drop the coal particles.

[0046] It should be noted that if there are directional indications involved in the embodiments of the present utility model, such as up, down, left, right, front, back..., then such directional indications are only used to explain the relative positional relationship, movement conditions, etc. between components in a specific posture as shown in the accompanying drawings. If this specific posture changes, then the directional indications will also change accordingly. Additionally, if there are descriptions involving "first", "second", etc. in the embodiments of the present utility model, then such descriptions of "first", "second", etc. are only for descriptive purposes and cannot be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. Additionally, the meaning of "and / or" that appears throughout the text includes three parallel scenarios. Taking "A and / or B" as an example, it includes Scenario A, or Scenario B, or the scenario where both A and B are satisfied simultaneously. Additionally, "a plurality of" means two or more. Furthermore, the technical solutions between various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist.

[0047] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A raw coal bunker for co-firing multiple coal types, characterized in that, Including: The coal feeding belt (10), the coal feeding bin (20) and the coal feeder (30); a partition plate (21) is provided in the coal feeding bin (20) to divide the working bin inside the coal feeding bin (20) into two coal storage bins; the coal feeding belt (10) is communicated with the feeding ports of the two coal storage bins and conveys two kinds of raw coal to the two coal storage bins respectively; the outlet of the coal storage bin is provided with a coal blending component for blending the raw coal in the two coal storage bins according to production requirements; the coal feeder (30) is docked with the coal blending component and conveys the raw coal blended by the coal blending component to the coal mill.

2. A multi-coal-type co-firing raw coal bunker according to claim 1, characterized in that, A pressure relief hole (211) communicating the two coal storage bins is provided on the partition plate (21).

3. A multi-coal type blended raw coal bunker according to claim 1 or 2, characterized in that, The coal feeding bin (20) is funnel-shaped; the partition plate (21) is located on the center line of the coal feeding bin (20), and the top of the partition plate (21) is flush with the top of the coal feeding bin (20), and the bottom of the partition plate (21) divides the discharge port of the coal feeding bin (20) into two equal parts to form the discharge ports of the two coal storage bins; the coal blending component includes a driving part and a blocking part; the blocking part is used for blocking the discharge ports of the two coal storage bins; the driving part is installed at the bottom of the partition plate (21) and is connected with the blocking part, and drives the blocking parts at the discharge ports of the two coal storage bins to move in turn according to production requirements.

4. A multi-coal type co-firing raw coal bunker according to claim 3, characterized in that, The blocking part includes two baffle plates (23); the two baffle plates (23) are both connected with the driving part and can respectively block the discharge ports of the two coal storage bins under the drive of the driving part.

5. A multi-coal type co-firing raw coal bunker according to claim 4, characterized in that, The driving part includes a driving motor and a motor rotating shaft (24); the motor rotating shaft (24) is connected with the two baffle plates (23), and the motor rotating shaft (24) drives the two baffle plates (23) to swing under the drive of the driving motor.

6. The multi-coal-type blended raw coal bunker according to claim 5, characterized in that, It also includes a first coal bin outlet gate (25), a first driving motor (251), a second coal bin outlet gate (26) and a second driving motor (261) provided at the outlet of the coal feeding bin (20); the first coal bin outlet gate (25) and the second coal bin outlet gate (26) are used for blocking the outlet of the coal feeding bin (20), and the first coal bin outlet gate (25), the second coal bin outlet gate (26) and the baffle plate (23) jointly enclose a mixing bin at the outlet of the coal feeding bin (20); the first driving motor (251) is used for driving the first coal bin outlet gate (25) to move; the second driving motor (261) is used for driving the second coal bin outlet gate (26) to move.

7. A multi-coal type blended raw coal bunker according to claim 6, characterized in that, It also includes air cannons (22); there are at least two air cannons (22), which are respectively arranged on both sides of the coal feeding bin (20) and are used for providing an air flow to promote the falling of the raw coal in the two working bins in the coal feeding bin (20).

Images