Ignition furnace of sintering machine

Abstract

The utility model discloses an ignition furnace of a sintering machine, which comprises a furnace body, the furnace body is provided with two rows of main burner components, the two rows of main burner components are symmetrically arranged along the center line of the top surface of the furnace body, each main burner component consists of a plurality of main burners, and the main burners of the two rows of main burner components are arranged in a staggered or opposite manner. According to the ignition furnace of the sintering machine, by improving the through-flow area proportion, the number and the arrangement of the air outlets of the main burners, the temperature uniformity of the charge level can be greatly improved, meanwhile, the average temperature of the charge level is increased, fuel is fully utilized, the through-flow area proportion of the air outlets of the main burners is properly increased, and the combustion efficiency is improved. Therefore, the through-flow area of the air outlet is increased, the retention time of the natural gas and the air in the furnace body can be prolonged, the air entrainment capability of the natural gas at the outlet of the main burner can be enhanced, the combustion efficiency is effectively improved, the charge level temperature of the ignition section is increased, and the temperature distribution uniformity is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of metallurgical equipment, in particular to an ignition furnace for a sintering machine. Background Art

[0002] The sintering machine ignition furnace is a key equipment in the sintering production process. Its process parameters are crucial to improving the quality of lead-zinc sintered ore products and reducing sintering energy consumption. As the primary link in the sintering process, the ignition process is the heat preparation stage in the early stage of the sintering process. The high-temperature material layer formed after ignition is also an important basis for the smooth progress of the sintering process. However, in the actual production process, the operation of the ignition process mostly relies on empirical methods, resulting in the failure to achieve the expected ignition effect, poor ignition quality, and high energy consumption.

[0003] The natural gas and air ejection speed of the main burner on the existing sintering machine ignition furnace is fast, the diffusion effect is weak, and the distribution in the furnace is affected by the flow field. As the combustion reaction proceeds, both will be continuously consumed, and the concentration will reach the lowest value near the material surface, which is not conducive to the mixed combustion of natural gas and air; the gas outlet flow rate of the main burner is large, the flame is too long, and the natural gas reaches the material surface before it is completely burned, which affects the ignition effect and increases the ignition energy consumption. Utility Model Content

[0004] In view of the problems existing in the current sintering machine ignition furnace, the utility model provides a sintering machine ignition furnace, which at least solves one problem existing in the prior art and has the characteristics of strengthening the combustion of natural gas and air and improving the flame length in the furnace.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0006] A sintering machine ignition furnace comprises a furnace body, wherein the furnace body is provided with two rows of main burner assemblies, which are symmetrically arranged along the center line of the furnace body top surface, and the main burner assemblies are composed of a plurality of main burners, and the main burners of the two rows of main burner assemblies are arranged alternately or relatively.

[0007] Furthermore, the main burner is provided with an air outlet, and the proportion of the air outlet flow area in the entire main burner outlet is set to 19.57%.

[0008] Furthermore, the numbers of the main burners 2 of the two rows of the main burner assemblies are set to 6 and 7, or 7 and 7 respectively.

[0009] Furthermore, the two rows of main burner assemblies are symmetrically distributed along the moving direction of the trolley.

[0010] Furthermore, the main burners of the main burner assembly are distributed in an array along the vertical direction of the movement of the trolley.

[0011] Furthermore, the main burner is arranged on the top of the furnace body and along the vertical direction of the furnace body.

[0012] Compared with the prior art, the utility model has the following beneficial effects:

[0013] The sintering machine ignition furnace of the utility model can greatly improve the temperature uniformity of the material surface by improving the proportion, number and arrangement of the air outlet flow area of ​​the main burner, while increasing the average temperature of the material surface, so that the fuel is fully utilized.

[0014] The utility model appropriately increases the proportion of the air outlet flow area of ​​the main burner, thereby increasing the air outlet flow area, which can extend the residence time of natural gas and air in the furnace body, and can enhance the air entrainment capacity of the natural gas at the main burner outlet, effectively improving the combustion efficiency, increasing the material surface temperature in the ignition section, and improving the uniformity of temperature distribution.

[0015] The main burners of the utility model adopt a "6+7" staggered arrangement or a "7+7" relative arrangement, which adjusts the flow distribution between different burners, reduces the speed difference between the main burner and the ignition burner, weakens the degree of mutual influence, and improves the flow rate of a single burner to indirectly adjust the flame length, which can effectively improve the temperature distribution in the ignition section area of ​​the material surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a front view of the ignition furnace structure of the sintering machine of the utility model;

[0017] Figure 2 This is a top view of the ignition furnace structure of the sintering machine of the utility model;

[0018] Figure 3 This is a simplified schematic diagram of the main burner structure of the utility model;

[0019] Figure 4 It is a schematic diagram of different arrangements of the main burners of the utility model;

[0020] Figure 5 This is a schematic diagram of the monitoring cross-sectional structure in the ignition furnace of the utility model, and the top surface of the ignition material layer is f1;

[0021] Figure 6 It is a schematic diagram of the division of different characteristic areas of the top material surface f1 of the ignition material layer in the ignition furnace of the present invention, including the ignition section area and the main burner material surface area;

[0022] Figure 7 It is a curve diagram of the average velocity of each cross section along the height direction of the ignition furnace under different air outlet flow area ratios of the main burner of the utility model;

[0023] Figure 8It is a simulation diagram of the temperature distribution of the monitoring section f1 under different air outlet flow area ratios of the main burner of the utility model;

[0024] Fig. 9 It is a curve diagram of the average temperature of the ignition section material surface and the temperature uniformity coefficient under different air outlet flow area ratios of the main burner of the utility model.

[0025] Fig.10 It is a simulation diagram of the temperature distribution of the monitoring section f1 under different arrangements of the main burner of the utility model;

[0026] Fig.11 The bar graph is a graph showing the average temperature and temperature uniformity coefficient of the ignition section material surface under different arrangements of the main burners of the utility model;

[0027] Figure numerals: 1: furnace body; 2: main burner; 3: ignition burner; 4: natural gas outlet section; 5: air outlet section. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0029] like Figure 2 As shown, the moving direction of the trolley is the arrow X direction, the two sides of the top of the furnace body 1 along the arrow X direction are set to the east side and the west side, the vertical direction of the trolley movement is the arrow Y direction, and the vertical direction of the furnace body 1 is set to the arrow Z direction. The overall structure of the furnace body 1 is as shown in FIG. Figure 1 As shown, the trolley is located at the bottom of the furnace body 1, and the ignition material is spread flat on the upper surface of the trolley. During operation, the furnace body 1 remains stationary, and the trolley carrying the ignition material continues to move slowly along the X direction. The flame jets of the single-row main burners leave a combustion zone corresponding to the single-row burners on the ignition material layer. As the trolley moves, the combustion zone expands to the entire material surface, thereby igniting the ignition material on the trolley.

[0030] like Figure 1 , Figure 2 and Figure 3 As shown, the utility model comprises a furnace body 1, at least two rows of main burner assemblies are arranged on the top of the furnace body 1, the main burner assembly is composed of a plurality of main burners 2, the main burners 2 are arranged on the top of the furnace body 1 and distributed along the vertical direction of the furnace body 1, and the main burners 2 are provided with a natural gas outlet and an air outlet, such as Figure 3The figure shows the natural gas outlet section 4 and the air outlet section 5 on the main burner 2. The size of the air outlet flow area of ​​the main burner 2 is closely related to the air outlet flow rate. Too high a flow rate will cause the flame to be too long, and it will be impossible to ignite the ignition material layer through the outer flame with the highest temperature, affecting the ignition quality. Increasing the air outlet flow area can reduce the air outlet flow rate, and adjust the flame length of the main burner 2 to meet the process requirements, so that the heat provided by the high-temperature outer flame can be fully utilized to promote the ignition of the material surface and further improve the uniformity of ignition. Therefore, this example sets the air outlet flow area of ​​the main burner 2 to account for 19.57% of the entire main burner outlet flow area. The preferred air outlet flow area of ​​the main burner 2 is 1860mm 2 .

[0031] The two rows of main burner assemblies are located on the east and west sides of the furnace body 1. For the convenience of distinction, the main burner assemblies located on the east side are defined as the east row of main burner assemblies, and the main burner assemblies located on the west side are defined as the west row of main burner assemblies. The east row of main burner assemblies and the west row of main burner assemblies are symmetrically arranged along the center line of the top surface of the furnace body 1. The east row of main burner assemblies and the west row of main burner assemblies are respectively composed of a number of main burners 2 distributed in an array in the vertical direction along the movement of the trolley.

[0032] The main burners 2 in the east row main burner assembly and the west row main burner assembly are arranged according to actual needs. The arrangement of the main burners 2 has an important influence on the combustion conditions in the furnace. In order to improve the combustion effect in the furnace, one is to improve the problem of poor ignition in the low temperature area of ​​the material surface by arranging the main burners 2, and the other is to reduce the distance between adjacent burners by increasing the number of main burners 2 in the east row main burner assembly and the west row main burner assembly, so as to form a more concentrated high temperature flame area on the material surface. Therefore, the main burners 2 of the east row main burner assembly of this embodiment are provided with 6, and the main burners 2 of the west row main burner assembly are provided with 6. There are 7 burners 2, and in the direction of arrow X, the main burners 2 of the east row of main burner assemblies are located between the adjacent main burners 2 of the west row of main burner assemblies, that is, they are staggered, or the main burners 2 of the east row of main burner assemblies and the main burners 2 of the west row of main burner assemblies are respectively provided with 7, and in the direction of arrow X, the main burners 2 of the east row of main burner assemblies and the main burners 2 of the west row of main burner assemblies correspond to each other one by one, that is, they are relatively arranged; that is, in this embodiment, the main burners 2 of the east row of main burner assemblies and the west row of main burner assemblies are arranged in a "6+7" staggered arrangement or a "7+7" relative arrangement.

[0033] See also Figure 5 In order to analyze the distribution law of multi-physical fields in the ignition furnace of the sintering machine, the monitoring section is defined along the height direction of the ignition furnace: a characteristic section parallel to the bottom surface of the ignition furnace is intercepted in the ignition furnace, that is, the top material surface f1 of the ignition material layer.

[0034] See also Figure 6In order to further analyze the temperature distribution law on the upper surface of the ignition material layer, especially the material surface area corresponding to the main burner 2, this paper divides the upper surface f1 of the ignition material into different characteristic areas, and defines the ignition section and the main burner 2 material surface area:

[0035] ① Ignition section area: Based on the center line of the east row main burner assembly and the west row main burner assembly, move an appropriate distance to both sides as two reference lines on the upper surface of the ignition material layer, and define the area within the two reference lines as the ignition section area corresponding to the east row main burner assembly and the west row main burner assembly, that is, Figure 6 The strip area corresponding to the positions of the middle row main burner assemblies and the west row main burner assemblies, and the material surface corresponding to the ignition section area are defined as the ignition section material surface.

[0036] ②Main burner 2 material surface area: In the ignition section area, a main burner 2 material surface area is set at appropriate intervals along the vertical direction of the trolley movement. Each main burner 2 corresponds to a material surface area. Figure 6 The area inside the middle frame line is the material surface area of ​​main burner No. 6 2.

[0037] Regarding the influence of the air outlet flow area ratio of the main burner 2 and the arrangement of the main burner 2 on the ignition process in the embodiment, the following analysis is performed in this embodiment:

[0038] (1) Investigate the influence of the flow area ratio of the main burner 2 air outlet on the ignition process:

[0039] This embodiment uses commercial simulation software to analyze the operating conditions of the main burner 2 at different air outlet flow area ratios (S=16.20%, 17.89%, 19.57% and 21.26%), and obtains the following results:

[0040] ① Velocity distribution results in the furnace:

[0041] According to the results of commercial simulation software, as the proportion of the air outlet flow area of ​​the main burner 2 increases, the average air flow rate gradually decreases, and the speed ratio of natural gas to air increases, thereby enhancing the natural gas's ability to entrain air and enhancing the circulating airflow in the furnace; at the point where the natural gas jet and the air jet meet at the outlet of the main burner 2, collisions between different molecules will become more frequent, accelerating the gas mixing process and effectively improving the combustion effect of natural gas.

[0042] from Figure 7It can be seen that as the proportion of the air outlet flow area of ​​the main burner 2 increases, the average velocity of the cross section gradually decreases, which increases the residence time of the gas in the furnace and strengthens the mixing of natural gas and air. It can be observed from the figure that within the furnace height range of 0.2m-0.6m, the average velocity of the cross section changes little. This is because the existence of the inclination angle of the ignition burner 3 allows the mixed gas at the outlet of the ignition burner 3 to flow and diffuse along the furnace height direction, ensuring the stability of the flow field. When the mixed gas moves to the vicinity of the material surface, the porous medium material layer increases the flow resistance of the gas, and the velocity drops sharply. The average flow velocity of the gas outlet is about 0.4m / s.

[0043] ② Temperature distribution results in the furnace:

[0044] from Figure 8 It can be seen from (monitoring section f1) that the change in the flow area of ​​the air outlet of the main burner 2 has a greater impact on the temperature distribution in the ignition section. As the proportion of the air outlet flow area increases, the natural gas and air at the outlet of the main burner 2 are better mixed; at the same time, the reduction in air flow rate not only increases the residence time of the gas in the furnace, but also effectively adjusts the length of the flame, allowing the high-temperature flame to develop more fully in the furnace, and strengthening the heat transfer between the high-temperature flame and the material surface. Figure 8 It can be observed that as the proportion of the air outlet flow area of ​​the main burner 2 increases, the area of ​​the high-temperature zone with a temperature higher than 1537K in the ignition section gradually increases, thereby providing more sufficient heat for the surface material and accelerating the ignition and combustion of the material surface.

[0045] In order to more intuitively judge the influence of different working conditions on the ignition quality of the ignition furnace, this embodiment introduces the average temperature of the ignition section material surface and the temperature uniformity coefficient of the ignition section material surface as evaluation indicators, which are as follows:

[0046] Among them, the calculation expression of the average temperature of the material surface in the ignition section is:

[0047]

[0048] In the formula, is the average temperature of the ignition section material surface, in K; A is the total area of ​​the ignition section material surface, in m 2 ; n is the total number of grids (the ignition section material surface is divided into many grids, each grid is a calculation unit of the simulation software); i is the i-th grid among all the grids on the ignition section material surface; A i is the area of ​​the ith grid, in m 2 ; T i is the average temperature of the ith grid, in K.

[0049] Among them, the temperature uniformity coefficient CV of the ignition section material surface area is defined as the ratio of the temperature standard deviation of the ignition section area to its average temperature. This value can reflect the degree of dispersion on the unit mean. Therefore, it can be considered that the temperature uniformity coefficient CV can reflect the temperature uniformity of the ignition section area. The smaller the CV, the smaller the dispersion of the ignition section material surface temperature and the more uniform the ignition; the larger the CV, the more uneven the temperature distribution of the ignition section material surface and the worse the ignition quality. The calculation expression of CV is

[0050]

[0051] Where CV is the temperature uniformity coefficient of the ignition section; σ is the temperature standard deviation of the ignition section, and its calculation expression is:

[0052]

[0053] Where, T j Represents the average temperature of the jth grid among all the grids on the material surface of the ignition section.

[0054] This embodiment takes into account that the existence of the high temperature ignition section in the sintering machine ignition furnace is an important basis for the ignition of the material surface, so the ignition section material surface temperature is analyzed in combination with the temperature uniformity coefficient:

[0055] from Fig. 9 From the change of the average temperature of the material surface in the ignition section, it can be seen that with the increase of the proportion of the air outlet flow area of ​​the main burner 2, the average temperature of the ignition section gradually increases. When the proportion of the air outlet flow area further increases from 19.57% to 21.26%, the speed difference between natural gas and air further increases, but the average temperature of the material surface in the ignition section no longer continues to increase, and basically stabilizes at around 1305℃.

[0056] from Fig. 9 From the change of the temperature uniformity coefficient CV in the ignition section, it can be seen that with the increase of the proportion of the air outlet flow area of ​​the main burner 2, the temperature uniformity coefficient of the ignition section material surface first decreases and then increases, and is smaller than the CV corresponding to the initial section, indicating that the uniformity of the material surface temperature has been greatly improved. This is because the high temperature area of ​​the ignition section material surface gradually increases, and at the same time, the temperature of the edge material surface is also significantly improved, which reduces the temperature difference in the ignition section area, and the temperature distribution is more uniform, which is conducive to the uniform ignition of the surface material and improves the ignition quality. Therefore, increasing the proportion of the air outlet flow area of ​​the main burner 2 can prolong the residence time of the mixed gas in the furnace, and can enhance the air entrainment capacity of the natural gas at the outlet of the main burner 2, effectively improving the combustion efficiency. With the increase of the proportion of the air outlet flow area, the temperature of the ignition section material surface gradually increases, and the uniformity of the temperature distribution is also improved. The optimal air outlet flow area proportion is 19.57%.

[0057] (2) Investigate the influence of the arrangement of the main burner 2 on the ignition process:

[0058] This embodiment uses commercial simulation software to analyze the operating conditions of the main burner 2 in different arrangements ("6+6", "6+7", "7+7"), and obtains the following results:

[0059] ① Velocity distribution results in the furnace:

[0060] According to the results of commercial simulation software, the "6+7" arrangement of the main burner 2 increases the number of main burners 2 in the east row of the main burner assembly, but the average outlet gas flow rate is higher than that of the main burner 2 in the west row of the main burner assembly; when the "7+7" arrangement is adopted, the outlet flow rate of the main burner 2 is further reduced, but the speed difference between the air and the natural gas remains basically unchanged; with the increase in the total number of main burners 2, the natural gas and air flow rates allocated to the ignition burner 3 continue to decrease, and the average outlet gas flow rate of the ignition burner 3 also gradually decreases.

[0061] ② Temperature distribution results in the furnace:

[0062] from Fig.10 It can be seen from (monitoring section f1) that when the main burner 2 adopts the "6+7" arrangement, the temperature distribution of the ignition section area on the east side where the east row of main burner assemblies are located is significantly improved, and the area of ​​the high temperature zone is increased. When the main burner 2 adopts the "7+7" arrangement, the main burners 2 of the east row of main burner assemblies and the west row of main burner assemblies are arranged symmetrically, and the distance between adjacent main burners 2 is reduced. The average flow rate at the outlet of main burner 2 is still higher than that of ignition burner 3. It can be observed that two continuous high-temperature ignition zones are formed on the material surface, which effectively promotes the uniform ignition of the material surface.

[0063] from Fig.11 It can be seen that the arrangement of the main burners 2 in "6+7" and "7+7" can not only increase the average temperature of the material surface in the ignition section, but also effectively improve the uniformity of the temperature distribution of the material surface. This is because the increase in the number of main burners 2 changes the flow distribution between the main burners 2 and the ignition burners 3, reduces the speed difference between the two, and weakens the mutual force. In addition, the closely arranged main burners 2 reduce the average flow velocity at the burner outlet, adjust the flame length, so that the high-temperature flame can be evenly sprayed onto the ignition layer material surface, strengthen the heat transfer between the high-temperature flame and the material surface, and strengthen the uniform distribution of the temperature of the ignition section material surface.

[0064] In summary, the use of this new sintering machine ignition furnace can greatly improve the temperature uniformity of the material surface, while increasing the average temperature of the material surface and making full use of the fuel.

Claims

1. A sintering machine ignition furnace, characterized in that: The invention comprises a furnace body, which is provided with two rows of main burner assemblies, which are symmetrically arranged along the center line of the top surface of the furnace body, and the main burner assemblies are composed of a plurality of main burners. The main burners of the two rows of main burner assemblies are arranged alternately or relatively, and the main burners are provided with air outlets. The proportion of the air outlet flow area in the entire main burner outlet is set to 19.57%, and the number of main burners of the two rows of the main burner assemblies is set to 6 and 7, or 7 and 7, respectively.

2. The sintering machine ignition furnace according to claim 1, characterized in that: The two rows of main burner assemblies are symmetrically distributed along the moving direction of the trolley.

3. The sintering machine ignition furnace according to claim 1, characterized in that: The main burners of the main burner assembly are arranged in an array along the vertical direction of movement of the trolley.

4. The sintering machine ignition furnace according to claim 1, characterized in that: The main burner is arranged on the top of the furnace body and along the vertical direction of the furnace body.

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