CN115949965A - Coal blending system and coal blending method - Google Patents
Coal blending system and coal blending method Download PDFInfo
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- CN115949965A CN115949965A CN202310027018.XA CN202310027018A CN115949965A CN 115949965 A CN115949965 A CN 115949965A CN 202310027018 A CN202310027018 A CN 202310027018A CN 115949965 A CN115949965 A CN 115949965A
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Abstract
The embodiment of the application discloses a coal blending system and a coal blending method, and the coal blending system provided by the embodiment of the application comprises: the coal blending assembly is arranged at a discharge hole of the raw coal bin, the coal blending assembly is provided with a plurality of feeding ports, each feeding port corresponds to a discharge hole of one sub-bin, coal leaving the raw coal bin through the coal blending assembly enters the coal feeder, in the actual use process, an operator needs to fill different coals into different sub-bins of the raw coal bin, under the normal condition, the raw coal bin is divided into a first sub-bin and a second sub-bin, high-quality coal types and economic coal types are respectively filled, the opening, closing and opening of the discharge hole of the coal blending assembly are adjusted to respectively control the speed of the different coal types entering the coal feeder from the raw coal bin, two or more different coal types are simultaneously supplied to one coal feeder of the raw coal bin, and the requirement of changing the boiler coal blending is met in real time.
Description
Technical Field
The embodiment of the application relates to the technical field of coal blending of thermal power plants, in particular to a coal blending system and a coal blending method.
Background
The coal blending combustion is one of important ways for meeting the shortage, complexity and changeability of fuel supply of a boiler of a coal-fired power station in China and improving the operation safety, economy and environmental protection of a unit, in general, new coal can be burnt only after old coal in a bin is burnt out, at present, a domestic coal-fired power generating set mainly adopts two modes of mixing coal before a furnace, mixing combustion in the furnace and mixing combustion in a grinding and pulverizing mode and mixing combustion in the furnace to carry out mixed coal blending combustion, which is limited by coal yard conditions, and the divided grinding and mixing combustion in the furnace become the main mode of mixed coal combustion of the boiler of the coal-fired power station, but the mode influences the operation of the unit, when the coal quality is high-heat bituminous coal, if a certain proportion of low-heat coal is blended, the output of a coal mill is increased when the coal is in full-load operation, the output of the coal mill is increased when the coal mill exceeds the maximum output, the load carrying phenomenon of the coal mill is influenced, in addition, the load increasing rate of the unit is also influenced by the low-heat coal blending combustion, along with the continuous increase of the scale of new energy loading scale in China, the requirement of a power grid system on the deep peak-fired power generating set is gradually improved, the flexibility of the coal-fired power generating set, the flexibility of the unit can be increased, the rated load can be reduced, the rated load of the unit can be increased, and can be reduced by 20 percent, and the rated load can be reduced by 20 percent, and the rated load can be reduced by 20 percent.
Disclosure of Invention
The present invention is directed to solving at least one of the problems of the prior art or the related art.
To this end, a first aspect of the invention provides a coal blending system.
The second aspect of the invention provides a coal blending method.
In view of this, according to a first aspect of embodiments of the present application, a coal blending system is provided, including:
the raw coal bin is used for storing raw coal;
the coal distributing plate is arranged inside the raw coal bin and is used for dividing the raw coal bin into a plurality of areas;
the coal blending assembly is provided with a plurality of feeding ports, and the feeding ports respectively correspond to the areas formed by separating the coal distributing plate;
and a feeding port of the coal feeder is connected to a discharge port of the coal blending assembly.
In a possible embodiment, the method further comprises:
and the conveying belts are arranged above the raw coal bunker, and the quantity of the conveying belts corresponds to that of the areas separated by the coal distribution plate.
In one possible embodiment, the upper surface of the coal distribution plate exceeds the gap between adjacent conveyor belts.
In one possible embodiment, the raw coal bunker includes:
a first coal dropping pipe;
the second coal dropping pipe is of a structure with a wide upper part and a narrow lower part, the discharge hole of the first coal dropping pipe is connected with the feeding hole of the second coal dropping hole, and the discharge hole of the second coal dropping pipe is communicated with the batching component.
In one possible embodiment, the coal blending assembly comprises:
the feeding port of the third coal dropping pipe is communicated with the discharging port of the second coal dropping pipe;
the first frame is arranged at the joint of the second coal dropping pipe and the third coal dropping pipe;
and the partition door is arranged on the first frame and corresponds to the area formed by separating the coal distribution plate.
In one possible embodiment, the coal blending assembly further comprises:
the second frames are arranged above the first frames, and the number of the second frames corresponds to the number of the areas formed by the coal distribution plates in a separated mode;
a rotating door provided inside the second frame;
and the output end of the variable speed motor is connected with the rotating door.
In one possible embodiment, the raw coal bunker further includes:
and the horn mouth is arranged on the upper side of the first coal dropping pipe and is connected with the feeding port of the first coal dropping pipe.
In one possible embodiment, the coal blending assembly further comprises:
and the stirring part is arranged in the third coal dropping pipe.
In one possible embodiment, the coal blending assembly further comprises:
the anti-collision rubber is arranged on the upper surface of the partition door.
According to a second aspect of the embodiments of the present application, there is provided a coal blending method applied to any one of the coal blending systems, including:
conveying different coal types into different areas in the raw coal bunker through a material conveying belt;
the blanking of each coal type is independently adjusted through a coal blending assembly;
and feeding coal to the target device through a coal feeder.
Compared with the prior art, the invention at least comprises the following beneficial effects:
the coal blending system that this application embodiment provided includes: the coal blending assembly is arranged at a discharge port of the raw coal bin, the coal blending assembly is provided with a plurality of feeding ports, each feeding port corresponds to a discharge port of one sub-bin, coal leaving the raw coal bin through the coal blending assembly enters the coal feeder and is finally put into use, in the actual use process, an operator needs to fill different coal into different sub-bins of the raw coal bin, under the common condition, the raw coal bin is divided into a first sub-bin and a second sub-bin, high-quality coal types and economic coal types are respectively filled, and the opening, the closing and the openness of the discharge port of the coal blending assembly are adjusted, the speed of different coal types entering the coal feeder from the raw coal bunker is respectively controlled, so that two or more different coal types are supplied to one raw coal bunker and one coal feeder simultaneously, the requirement of changing the coal blending of a boiler is realized in real time, the aim of quickly changing the coal types is realized, the requirements of different loads of the boiler on the coal quality are met, the change of the unit load is quickly responded, the defects that the time lag in the conventional coal blending process cannot be changed in time, the coal types cannot be changed in time, and the accurate coal blending situation when the load is changed quickly cannot be met are thoroughly changed, the unit load is realized to be up at the peak top and down at the valley, and the contradiction between the unit load response and the accurate coal blending is fundamentally solved.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:
FIG. 1 is a block diagram of a coal blending system according to an embodiment of the present disclosure;
FIG. 2 is a flow chart illustrating exemplary steps of a coal blending method according to an embodiment provided herein.
Wherein, the corresponding relation between the reference numbers and the part names in fig. 1 is:
100. a raw coal bunker; 200. a coal distributing plate; 300. a coal blending assembly; 400. a coal feeder; 500. a material conveying belt;
110. a first coal dropping pipe; 120. a second coal dropping pipe; 130. a bell mouth;
310. a third coal dropping pipe; 320. a first frame; 330. a partition door.
Detailed Description
In order to better understand the technical solutions described above, the technical solutions of the embodiments of the present application are described in detail below with reference to the drawings and the specific embodiments, and it should be understood that the specific features of the embodiments and the embodiments of the present application are detailed descriptions of the technical solutions of the embodiments of the present application, and are not limitations of the technical solutions of the present application, and the technical features of the embodiments and the embodiments of the present application may be combined with each other without conflict.
As shown in fig. 1, according to an embodiment of the present application, a coal blending system is provided, including: a raw coal bunker 100, the raw coal bunker 100 being used for storing raw coal; the coal distribution plate 200, the coal distribution plate 200 is arranged inside the raw coal bunker 100, and is used for dividing the raw coal bunker 100 into a plurality of areas; the coal blending assembly 300 is provided with a plurality of feeding ports, and the feeding ports correspond to the areas formed by separating the coal distributing plate 200 respectively; the feed inlet of the coal feeder 400 is connected to the discharge outlet of the coal blending assembly 300.
The coal blending system that this application embodiment provided includes: the coal blending assembly 300 is arranged at a discharge port of the raw coal bin 100, the coal blending assembly 300 is provided with a plurality of feeding ports, each feeding port corresponds to a discharge port of a branch bin, coal leaving the raw coal bin 100 through the coal blending assembly 300 enters the coal feeder 400 and is finally put into use, in the actual use process, an operator needs to fill different coals into different branch bins of the raw coal bin 100, under the normal condition, the raw coal bin 100 is divided into a first branch bin and a second branch bin which are respectively filled with high-quality coal types and economic coal types, and the opening, the closing and the openness of the discharge port of the coal blending assembly 300 are adjusted, the speed of different coal types entering the coal feeder 400 from the raw coal bunker 100 is respectively controlled, so that two or more different coal types are supplied to one raw coal bunker 100 and one coal feeder 400 at the same time, the requirement of boiler coal blending is changed in real time, the purpose of quickly changing the coal types is realized, the requirements of different loads of a boiler on the coal quality are met, the change of unit load is quickly responded, the defects that the time lag in the conventional coal blending process cannot be changed in time, the accurate coal blending situation when the load is changed quickly cannot be met are thoroughly changed, the unit load is improved, the 'top of a peak is improved, the valley is reduced', the contradiction between unit load response and accurate coal blending is fundamentally solved, the coal blending amount of the contradiction of economic coal types is improved, and the economic benefit of the production process is improved.
As shown in fig. 1, in some examples, the coal blending system further includes a material conveying belt 500, the material conveying belt 500 is disposed above the raw coal bunker 100, and the number of the material conveying belts 500 corresponds to the number of the areas into which the coal distributing plate 200 is divided.
In this technical scheme, add fortune material belt 500 above raw coal bunker 100, fortune material belt 500 quantity is corresponding with the region that raw coal bunker 100 separated formed, transports raw coal to raw coal bunker through fortune material belt 500, and the raw coal that transports fortune material belt 500 was transported later supplies into raw coal bunker 100 with the help of manpower or plough tripper, promotes coal charge transport efficiency, reduces artifical work, promotes the ease of this application embodiment.
As shown in fig. 1, in some examples, the upper surface of the coal distribution plate 200 exceeds the gap between adjacent conveyor belts.
In this technical scheme, the upper surface of coal-distributing plate 200 surpasses the upper surface of raw coal bunker 100, stretch into adjacent fortune material belt 500's clearance, because of in the in-process of fortune material belt 500 fortune coal and transportation, often have the coal cinder to drop, for avoiding the coal charge on the fortune material belt 500 to get into the raw coal bunker 100 branch storehouse of non-correspondence, cause the coal type to mix, effect when influencing the coal charge ratio, consequently, increase coal-distributing plate 200 height, make during its stretches into fortune material belt 500's clearance, play the separation effect, increase the practicality of this application embodiment.
As shown in fig. 1, in some examples, the raw coal bin 100 includes: a first coal dropping pipe 110; the second coal dropping pipe 120 is of a structure with a wide upper part and a narrow lower part, the discharge hole of the first coal dropping pipe 110 is connected with the feeding hole of the second coal dropping hole, and the discharge hole of the second coal dropping pipe 120 is communicated with the batching component.
In the technical scheme, the raw coal bunker 100 comprises a first coal dropping pipe 110 and a second coal dropping pipe 120, the first coal dropping pipe 110 is communicated with the second coal dropping pipe 120, meanwhile, the first coal dropping pipe 110 and the second coal dropping pipe 120 are integrally split by a coal distributing plate 200, the first coal dropping pipe 110 and the coal distributing plate 200 jointly enclose to form a plurality of sub-bunkers, wherein the first coal dropping pipe 110 has a large inner space and is used for storing a large amount of coal, so that the coal is supplied to the coal mining machine 400, the frequency of supplementing the coal into the raw coal bunker 100 is reduced, the coal adding pressure of workers is reduced, meanwhile, the second coal dropping pipe 120 adopts a structure with a large upper opening and a small lower opening, and the lower end structure of the raw coal bunker 100 is narrowed to be matched with the size of a coal inlet of the coal blending assembly 300, so that the integrity of the production embodiment is realized.
As shown in fig. 1, in some examples, the coal blending assembly 300 includes: a third coal dropping pipe 310, wherein a feeding hole of the third coal dropping pipe 310 is communicated with a discharging hole of the second coal dropping pipe 120; the first frame 320, the first frame 320 is arranged at the connection position of the second coal dropping pipe 120 and the third coal dropping pipe 310; and the partition door 330, the partition door 330 is arranged on the first frame 320, and the partition door 330 corresponds to the area formed by the coal distribution plate 200.
In the technical scheme, the coal blending assembly 300 comprises a third coal dropping pipe 310, a first frame 320 and partition doors 330, wherein the first frame 320 is internally divided into a plurality of areas, the areas correspond to the coal bunker 100 sub-bins, each area on the first frame 320 is provided with a partition door 330, in actual production, the partition doors 330 adopt pneumatic spile doors, when the partition doors 330 are opened, coal in the corresponding coal bunker 100 sub-bins falls to the third coal dropping pipe 310 and finally enters the coal feeder 400, after the partition doors 330 are closed, the coal in the coal bunker 100 sub-bins stops falling, and the opening degree of the partition doors 330 can be controlled through the pneumatic spile doors, so that coal blending is further realized.
In some examples, the coal blending assembly 300 further comprises: the second frames are arranged above the first frames 320, and the number of the second frames corresponds to the number of the areas formed by the coal distribution plate 200 in a separated mode; the rotating door is arranged inside the second frame; and the output end of the variable speed motor is connected with the rotating door.
In the technical scheme, the coal blending assembly 300 further comprises a second frame, a rotating door and a variable speed motor, wherein the bottom of each raw coal bunker 100 can be provided with the second frame, the second frame is transversely arranged on the raw coal bunkers 100, the rotating door is arranged in the second frame, and the output end of the variable speed motor is connected with the rotating door.
As shown in fig. 1, in some examples, the raw coal bunker 100 further includes a bell mouth 130, and the bell mouth 130 is disposed on an upper side of the first coal dropping pipe 110 and connected to the feeding port of the first coal dropping pipe 110.
In the technical scheme, the bell mouth 130 is additionally arranged above the raw coal bin 100, so that the scattering of coal materials in the process of transferring the coal materials from the material conveying belt 500 to the raw coal bin 100 is reduced, and the breakage rate in the production process is reduced.
In some examples, the coal blending assembly 300 further includes an agitation portion disposed inside the third coal drop tube 310.
In this technical solution, a stirring portion is additionally disposed inside the third coal dropping pipe 310, and in some embodiments, the stirring portion may be a longitudinal rotating door, and different coal types are scattered and mixed in the third coal dropping pipe 310, so as to avoid the influence on the coal burning efficiency due to stacking and piling of different coal types in the coal feeder 400.
In some examples, the coal distribution assembly 300 further includes a crash rubber disposed on an upper surface of the partition door 330.
In this technical scheme, add the anticollision rubber, avoid the direct striking coal blending subassembly 300 of coal charge to influence the life of coal blending subassembly 300.
As shown in fig. 2, the embodiment of the present application provides a coal blending method applied to any one of the coal blending systems described above, including:
step 101: conveying different coal types into different areas in the raw coal bin through a material conveying belt;
step 102: the blanking of each coal type is independently adjusted through the coal blending assembly;
step 103: and feeding coal to the target device through a coal feeder.
According to the coal blending method provided by the embodiment of the application, the blanking proportions of different coal types are adjusted in real time by adjusting the coal blending assembly, the mixed coal materials are sent into the coal feeder, the accurate adjustment of boiler combustion is realized, the flexibility requirement of the thermal power generating unit is met, the requirement of exerting auxiliary service of the unit is met, the advantages of the thermal power generating enterprise are exerted in the aspects of participating in power grid auxiliary service, frequency modulation and the like, the competitiveness of the thermal power generating enterprise is improved, huge benefits are brought to the enterprise for increasing and saving income and expenditure, the blending combustion amount of economic coal types is improved, the requirement of rapid variable load all day is flexibly met, powerful guarantee is provided for the enterprise for increasing the loss and increasing the quality and efficiency, and further the market competitiveness of the enterprise is improved.
In the present invention, the terms "first", "second", and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; the term "plurality" means two or more unless expressly limited otherwise. The terms "mounted," "connected," "fixed," and the like are to be construed broadly, and for example, "connected" may be a fixed connection, a removable connection, or an integral connection; "connected" may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.
In the description of the present invention, it is to be understood that the terms "upper", "lower", "left", "right", "front", "rear", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred device or unit must have a specific direction, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.
In the description herein, the description of the terms "one embodiment," "some embodiments," "specific embodiments," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A coal blending system, comprising:
a raw coal bunker for storing raw coal;
the coal distributing plate is arranged inside the raw coal bin and is used for dividing the raw coal bin into a plurality of areas;
the coal blending assembly is provided with a plurality of feeding ports, and the feeding ports respectively correspond to the areas formed by separating the coal distributing plate;
and a feeding port of the coal feeder is connected to a discharge port of the coal blending assembly.
2. The coal blending system of claim 1, further comprising:
and the conveying belt is arranged above the raw coal bunker, and the quantity of the conveying belt corresponds to the quantity of the areas separated by the coal distribution plate.
3. The coal blending system of claim 2, wherein:
the upper surface of the coal distribution plate exceeds the gap between the adjacent conveying belts.
4. The coal blending system of claim 1, wherein the raw coal bunker comprises:
a first coal dropping pipe;
the second coal dropping pipe is of a structure with a wide upper part and a narrow lower part, the discharge hole of the first coal dropping pipe is connected with the feeding hole of the second coal dropping hole, and the discharge hole of the second coal dropping pipe is communicated with the batching component.
5. The coal blending system of claim 4, wherein the coal blending assembly comprises:
the feeding port of the third coal dropping pipe is communicated with the discharging port of the second coal dropping pipe;
the first frame is arranged at the joint of the second coal dropping pipe and the third coal dropping pipe;
and the partition door is arranged on the first frame and corresponds to an area formed by separating the coal distribution plate.
6. The coal blending system of claim 5, wherein the coal blending assembly further comprises:
the second frames are arranged above the first frames, and the number of the second frames corresponds to the number of the areas formed by the coal distribution plates in a separated mode;
a rotating door disposed inside the second frame;
and the output end of the variable speed motor is connected with the rotating door.
7. The coal blending system of claim 4, wherein the raw coal bunker further comprises:
and the horn mouth is arranged on the upper side of the first coal dropping pipe and is connected with the feeding port of the first coal dropping pipe.
8. The coal blending system of claim 5, wherein the coal blending assembly further comprises:
and the stirring part is arranged in the third coal dropping pipe.
9. The coal blending system of claim 5, wherein the coal blending assembly further comprises:
the anti-collision rubber is arranged on the upper surface of the partition door.
10. A coal blending method applied to the coal blending system according to any one of claims 1 to 9, comprising:
conveying different coal types into different areas in the raw coal bunker through a material conveying belt;
the blanking of each coal type is independently adjusted through the coal blending assembly;
and feeding coal to the target device through a coal feeder.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202310027018.XA CN115949965A (en) | 2023-01-09 | 2023-01-09 | Coal blending system and coal blending method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202310027018.XA CN115949965A (en) | 2023-01-09 | 2023-01-09 | Coal blending system and coal blending method |
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| CN115949965A true CN115949965A (en) | 2023-04-11 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117657815A (en) * | 2023-12-13 | 2024-03-08 | 万平 | Coal-fired power plant compartment coal blending device and method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117657815A (en) * | 2023-12-13 | 2024-03-08 | 万平 | Coal-fired power plant compartment coal blending device and method |
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