Department type two-way feeding system

Abstract

The utility model discloses a determinant two-way feeding system which at least comprises a first raw coal hopper and a second raw coal hopper, and the first raw coal hopper and the second raw coal hopper are the same in structure. A conveying pipeline is connected between the first raw coal hopper and the second raw coal hopper, and a determinant feeder is arranged in the conveying pipeline; the lower end of the first raw coal hopper communicates with a coal falling pipe. The coal gate is arranged between the first raw coal hopper and the coal falling pipe. An inner cone is arranged on the side, close to the coal falling pipe, of the first raw coal hopper, and a runner allowing raw coal to pass through is arranged between the inner cone and the first raw coal hopper. Feeding holes are symmetrically formed in the contact side of the inner cone and the runner; baffle assemblies are symmetrically arranged between the inner cone and the first raw coal hopper and located at the upper end of the feeding port; according to the utility model, the contradiction between the unit load response rate and the accurate coal blending co-combustion is fundamentally solved, and the coal type combination of the supplied coal can be quickly adjusted according to the requirements of the unit.

Description

Technical Field

[0001] The utility model relates to the technical field of material distribution, in particular to a determinant-type bidirectional feeding system. Background Art

[0002] Domestic and foreign research on mixed coal combustion technology has been carried out for many years, and rich results have been achieved. At present, domestic coal-fired power generation units mainly adopt two methods of "mixing before the furnace, mixed combustion in the furnace" and "grinding and pulverizing separately, mixed combustion in the furnace" to carry out mixed coal combustion. Coal blending before the furnace mainly includes coal blending in the coal yard and coal blending on the boiler coal conveyor belt; in-furnace blending is achieved by putting different types of coal into the coal mill and adjusting the output of the coal mill according to the load.

[0003] Coal blending in coal yards: Coal storage yards will place coals of different qualities according to the quality of the coal, such as high-quality coal, general coal, low calorific value coal, and extremely poor coal. In order to achieve coal blending and combustion, coal in coal storage yards can be stored in vertical stacking and horizontal retrieval or horizontal stacking and vertical retrieval. Based on the actual situation of the coal storage yard, the length, height, and width of the stacking sites for different types of coal are reasonably set. On this basis, with the help of coal stackers, coal is stacked vertically or horizontally, and the coal retrieval process is horizontal or vertical retrieval, so that mixing can be achieved during the coal retrieval process. Coal blending in coal yards helps in the comprehensive scheduling of fuel, but it occupies a large area, is too costly, and lacks flexibility and real-time performance, and cannot adjust the coal ratio in time according to boiler demand.

[0004] Coal blending on the coal conveyor belt: Coal blending is carried out by using double-line gap coal trough, coal conveyor belt, variable frequency impeller coal feeder, etc. Different types of coal are placed on the A and B sides of the double-line gap coal trough. During the coal pushing process, according to the standard coal quality data and boiler coal burning requirements, the variable frequency impeller coal feeder is started, the set value is adjusted, and the coal on the A and B sides is blended on the belt, and then transmitted to the boiler through the belt for blended coal combustion. This method has poor coal blending uniformity, and its mixed coal ratio is not easy to accurately control, and uneven coal blending may affect the safe and economical operation of the boiler.

[0005] Separate grinding and pulverizing, in-furnace blending: Different types of raw coal are fed into different pulverizers to be ground into coal powder, and then enter the furnace through different layers of burners for blending. This blending method is suitable for power plants with few coal blending means and equipment, especially for coal types with large differences in grindability. The fineness of different types of coal powder can be completely controlled by different pulverizers, and different layers of burners and different air distribution methods can be selected according to the coal quality and combustion characteristics. For example, coal that is not easy to slag is fed into the burner in the high heat load area to effectively reduce the slag tendency in the furnace burner area. This blending method overcomes the disadvantage that the burnout characteristics of mixed coal are close to those of difficult-to-burn coal, and avoids the combustion stability problems caused by uneven blending in front of the furnace. Limited by coal yard conditions, "separate grinding and pulverizing, in-furnace blending" has become the main method of blending coal for coal-fired power plant boilers. This method has the advantages of small footprint and convenient operation, but it affects the flexibility of unit operation.

[0006] Reconstruction of the raw coal hopper compartment: Install a vertical partition in the center of the raw coal hopper to divide the raw coal hopper into two parts, and store different types of coal on each side. Install gate doors on both sides of the lower area of ​​the raw coal hopper to control the coal flow on each side. The type of coal entering the coal feeder is controlled by opening the gate doors on both sides to achieve the purpose of rapid change of coal types. This method can meet the purpose of rapid change of coal types, but because the cross-section of the coal flow outlet is reduced by more than half, it is very easy to cause coal blockage in the raw coal hopper. Secondly, unilateral coal discharge will cause the raw coal hopper to be biased, which is very unfriendly to the force of the raw coal hopper and easily cause hidden dangers such as deformation and failure of the raw coal hopper support structure.

[0007] In view of the fact that the effects of the above-mentioned mixed coal technologies are not ideal, it is urgent to develop a safe, flexible, effective and practical technical method to solve the mixed combustion solution under the new model. Summary of the invention

[0008] The utility model aims to provide a determinant bidirectional feeding system in view of the problems and shortcomings described in the background technology.

[0009] A determinant bidirectional feeding system comprises at least a first raw coal hopper and a second raw coal hopper, wherein the first raw coal hopper and the second raw coal hopper have the same structure;

[0010] A conveying pipeline is connected between the first raw coal hopper and the second raw coal hopper, and a matrix feeder is arranged in the conveying pipeline;

[0011] The lower end of the first raw coal hopper is connected to a coal drop pipe, and a coal gate is arranged between the first raw coal hopper and the coal drop pipe;

[0012] An inner cone is provided on the first raw coal hopper near the coal drop pipe, and a flow channel is provided between the inner cone and the first raw coal hopper for raw coal to pass through;

[0013] The inner cone is symmetrically provided with a feed port on the contact side with the flow channel;

[0014] A baffle assembly is symmetrically provided between the inner cone and the first raw coal hopper at the upper end of the feed inlet;

[0015] The raw coal in the first raw coal hopper can fall into the matrix feeder through the feed port arranged on the inner cone.

[0016] Preferably, the upper end of the inner cone is a conical structure.

[0017] Preferably, the inner cone is arranged at the center axis of the first raw coal hopper.

[0018] Preferably, both ends of the delivery pipeline are closed structures.

[0019] Preferably, the matrix feeder is a spiral feeder or a conveyor belt scraper feeder.

[0020] Beneficial effects of the utility model:

[0021] 1. The system is simple. The transformation content is to open the local hole of the raw coal hopper and the transformation of the lower coal drop pipe. The change to the original equipment of the unit is small, and the impact on the operation of the original system of the unit is also small;

[0022] 2. The operation mode is simple and flexible. When the system is put into operation, you only need to operate the coal gate and baffle assembly, and adjust the motor speed of the determinant feeder as needed;

[0023] 3. After the transformation, different types of coal can be accurately switched in real time to meet the peak-shaving needs of rapidly changing loads throughout the day. High loads and minimum stable combustion loads use high calorific value coal, and other loads use low calorific value coal, which improves the load response speed and increases the amount of mixed combustion of low calorific value coal, achieving the triple benefits of peak-shaving, capacity electricity price and mixed combustion, which is beneficial to improving the competitiveness of enterprises;

[0024] 4. The raw coal hopper itself is a large coal storage device. This technology is based on the design concept of "determinant bidirectional feeding system". Under the premise of ensuring that the overall flow of raw coal in the raw coal hopper is not affected, the determinant feeder is installed in the raw coal hopper to achieve the function of quantitatively conveying raw coal between two adjacent raw coal hoppers, thereby ensuring the flexibility of unit operation;

[0025] 5. The determinant bidirectional feeding system technology can meet the peak load of the unit and reduce the trough load, which fundamentally solves the contradiction between the unit load response rate and the precise coal blending and mixed combustion. It can quickly adjust the coal type combination of the coal supply according to the unit demand, improve the coal blending capacity while improving the peak-shaving and peak-loading capabilities of the unit, meet economical combustion, and help the unit obtain peak-shaving and capacity electricity price income. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the utility model;

[0027] Figure 2 It is a structural schematic diagram of the raw coal in the first raw coal hopper flowing into the coal drop pipe;

[0028] Figure 3 It is a structural schematic diagram of the raw coal in the first raw coal hopper flowing into the second raw coal hopper through the matrix feeder. DETAILED DESCRIPTION

[0029] Referring to the attached drawings, a matrix type bidirectional feeding system comprises at least a first raw coal hopper 1 and a second raw coal hopper 2, and the first raw coal hopper 1 and the second raw coal hopper 2 have the same structure;

[0030] A conveying pipeline 3 is connected between the first raw coal hopper 1 and the second raw coal hopper 2, and a matrix feeder 4 is arranged in the conveying pipeline 3;

[0031] The lower end of the first raw coal hopper 1 is connected to a coal dropping pipe 5, and a coal gate 6 is arranged between the first raw coal hopper 1 and the coal dropping pipe 5;

[0032] An inner cone 7 is provided on the first raw coal hopper 1 near the coal drop pipe 5, and a flow channel 8 is provided between the inner cone 7 and the first raw coal hopper 1 to allow raw coal to pass through.

[0033] A feed port 9 is symmetrically provided on the contact side between the inner cone 7 and the flow channel 8;

[0034] A baffle assembly 10 is symmetrically provided between the inner cone 7 and the first raw coal hopper 1 at the upper end of the feed port 9;

[0035] The raw coal in the first raw coal hopper 1 can fall into the matrix feeder 4 through the feed port 9 arranged on the inner cone 7.

[0036] Furthermore, the upper end of the inner cone 7 is in a conical structure.

[0037] Furthermore, the inner cone 7 is arranged at the center axis of the first raw coal hopper 1 .

[0038] Furthermore, both ends of the delivery pipeline 3 are closed structures.

[0039] Furthermore, the matrix feeder 4 may be a spiral feeder or a conveyor belt scraper feeder known in the prior art.

[0040] Furthermore, the coal gate 6 and the baffle assembly 10 are known structures in the prior art and act as valves. They may be electric coal gate 6, electric baffle assembly 10 or hydraulic electric coal gate 6, hydraulic baffle assembly 10. This structural component is not the core concept of this practical information and is recorded in many patent documents, so it will not be elaborated here.

[0041] The working process and use principle of this utility model:

[0042] When coal blending is not required:

[0043] See also Figure 2 As shown, the matrix feeder 4 is not working, the coal gate 6 and the baffle assembly 10 are in the open state, and the raw coal in the first raw coal hopper 1 flows downward along the flow channel 8 until it remains in the coal drop pipe 5. Although a feed port 9 is provided on the contact side of the inner cone 7 with the flow channel 8, part of the raw coal will enter the feed port 9, but because the matrix feeder 4 is not working, the raw coal will continue to flow downward along the flow channel 8 to the coal drop pipe 5 and finally enter the coal mill.

[0044] When coal blending is required:

[0045] See also Figure 1 and Figure 3 As shown, here, the example of transferring part of the raw coal in the second raw coal hopper 2 to the lower end of the first raw coal hopper 1 is used for explanation;

[0046] First, the baffle assembly 10 provided on the second raw coal hopper 2 is closed to stop the raw coal in the second raw coal hopper 2 from falling; the coal gate 6 provided on the second raw coal hopper 2 is in an open state;

[0047] The baffle assembly 10 provided on the first raw coal hopper 1 is opened, and the coal gate 6 provided on the first raw coal hopper 1 is in a closed state;

[0048] The linear feeder 4 is in working condition;

[0049] The raw coal in the first raw coal hopper 1 flows downward along the flow channel 8. Since the coal gate 6 provided on the first raw coal hopper 1 is in a closed state, the raw coal is accumulated at the lower end of the first raw coal hopper 1. Since the matrix feeder 4 is in a working state, the raw coal in the first raw coal hopper 1 enters the matrix feeder 4 through the feed port 9 along the flow channel 8. The matrix feeder 4 transfers the raw coal in the first raw coal hopper 1 to the second raw coal hopper 2, and discharges the raw coal through the feed port 9 at the inner cone 7 on the second raw coal hopper 2. The raw coal flows into the coal drop pipe 5 at the lower end of the second raw coal hopper 2.

Claims

1. A determinant bidirectional feeding system, characterized in that: At least comprising a first raw coal hopper and a second raw coal hopper, the first raw coal hopper and the second raw coal hopper having the same structure; A conveying pipeline is connected between the first raw coal hopper and the second raw coal hopper, and a matrix feeder is arranged in the conveying pipeline; The lower end of the first raw coal hopper is connected to a coal drop pipe, and a coal gate is arranged between the first raw coal hopper and the coal drop pipe; An inner cone is provided on the first raw coal hopper near the coal drop pipe, and a flow channel is provided between the inner cone and the first raw coal hopper for raw coal to pass through; The inner cone is symmetrically provided with a feed port on the contact side with the flow channel; A baffle assembly is symmetrically provided between the inner cone and the first raw coal hopper at the upper end of the feed inlet; The raw coal in the first raw coal hopper can fall into the matrix feeder through the feed port arranged on the inner cone.

2. A determinant bidirectional feeding system according to claim 1, characterized in that: The upper end of the inner cone is in a cone-shaped structure.

3. A determinant bidirectional feeding system according to claim 1, characterized in that: The inner cone is arranged at the center axis of the first raw coal hopper.

4. A determinant bidirectional feeding system according to claim 1, characterized in that: Both ends of the conveying pipeline are closed structures.

5. A determinant bidirectional feeding system according to claim 1, characterized in that: The matrix feeder is a spiral feeder or a conveyor belt scraper feeder.

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