Coke oven gas, ammonia gas and steam coupling injection device for sintering material surface and control method thereof

Abstract

The invention discloses a sintering material surface coke oven gas, ammonia gas and steam coupling injection device which comprises a sintering machine trolley, an injection cover, a coke oven gas injection device, an ammonia gas injection device and a steam injection device. According to the sintering material surface coke oven gas ammonia gas steam coupling injection device, sintering material surface coupling injection is carried out through coke oven gas, ammonia gas and steam, and coupling injection application of carbon-hydrogen-free gas fuel and carbon-hydrogen-based gas fuel in the sintering process is achieved; and the injection amounts of coke oven gas, ammonia gas and steam are automatically controlled and adjusted within a process control range, so that a relatively good coupling effect and actual effects of reducing carbon and emission are obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of sintering, in particular to a coke oven gas and ammonia steam coupled injection device for a sintering material surface and a use method thereof. Background Art

[0002] The sintering process is a key link in the ironmaking process. Its principle is to mix various powdered iron-containing raw materials with appropriate amounts of fuel and flux, add appropriate amounts of water, mix and pelletize them, and then use the sintering equipment to make the materials undergo a series of physical and chemical changes, sintering them into blocks, and then send them to the blast furnace for the next process.

[0003] To reduce the coke ratio and smelting costs of blast furnace ironmaking, blast furnaces often require sintered ore with high strength and high reducibility. The sintering process generally requires high strength, high yield, low return rate, and low fuel consumption. High-strength and high-reducibility sintered ore consumes less coke during blast furnace smelting, thereby reducing CO2 emissions. From a long-term perspective, CO2 emission reduction requirements will become a bottleneck restricting the development of the steel industry. According to relevant data, CO2 emissions from sintering and blast furnace processes account for approximately 60% of total industrial emissions. Therefore, both from the perspective of reducing costs for enterprises and from the perspective of environmental protection, reducing the proportion of solid fuel consumed in sintering and lowering the fuel ratio of blast furnace charge materials have become urgent ironmaking technology needs.

[0004] The principle of gas injection technology is to inject a combustible gas onto the sintering charge surface. Under the negative pressure of the exhaust air, the combustible gas is drawn into the charge layer for combustion and heat generation. This replenishes heat in the heat-deficient upper charge layer, optimizes the temperature field in the upper charge layer, and solves the problem of uneven heat distribution in the charge layer. In 2009, Japan's JFE Group implemented natural gas injection on the sintering charge surface for industrial use, reducing fuel consumption by 3kg per ton of sintered ore and reducing CO emissions by 260,000 tons per year. Subsequently, Meishan Iron and Steel Corporation implemented coke oven gas injection on sintering machines, also achieving industrial production and reducing fuel consumption by 7.3%.

[0005] In terms of controlling the high-temperature combustion atmosphere, Nippon Steel Corporation was the first to conduct research on injecting steam onto the sintering material surface, using water vapor to promote fuel combustion; India's BSP Company and China's Shagang and Shougang have successively carried out industrial trials and production practices of surface steam injection. In 2016, Shougang Jingtang applied steam injection, reducing solid fuel consumption by 1.64kg / t and having the effect of inhibiting the formation of dioxins.

[0006] Among them, relevant scholars from Central South University studied the influence of coupled gas and water vapor injection on sintering. The results showed that under suitable gas injection and water vapor injection systems, the sintering indicators were improved compared with when the two were injected separately, indicating that the coupling of the two had a superimposed effect on the improvement of sintering indicators; under suitable gas injection conditions, the sintering indicators obtained by variable-intensity step-by-step injection of water vapor were better, and the solid fuel consumption per ton of sintered ore could be reduced by about 7kg (standard coal), NOx emissions were reduced by about 16%, and CO emissions were reduced by about 20%.

[0007] Currently, research and application of coupled sintering fuel injection primarily focuses on hydrocarbon-based gas fuels such as natural gas, coke oven gas, and blast furnace gas, as well as steam, or their combination with biochar during sintering. Based on the excellent properties of ammonia, which is carbon-free and easy to store and transport, a method for coupled injection of coke oven gas, ammonia, and steam during sintering has been proposed. This method utilizes the combustion properties of ammonia and the redox reaction of the NO it produces with CO to achieve supplemental heating of the sintering bed and improve the combustion efficiency of the solid fuel used in sintering. This minimizes fossil fuel consumption and provides a new reference solution for industrial practice in low-carbon sintering and further emission reductions. Summary of the Invention

[0008] The object of the present invention is to provide a coke oven gas and ammonia steam coupled injection device for a sintering material surface and a method for using the same, so as to solve the problems raised in the above background technology.

[0009] To achieve the above object, the present invention provides the following technical solution: a sintering material surface coke oven gas and ammonia steam coupled injection device comprises a sintering machine trolley; an injection hood, wherein the sintering machine trolley is located in the injection hood;

[0010] The coke oven gas injection device includes a coke oven gas injection main pipe, a coke oven gas injection branch pipe, and a coke oven gas injection pipe bank. The coke oven gas injection main pipe is arranged outside the injection hood, and the coke oven gas injection pipe bank is arranged inside the injection hood and located above the sintering machine trolley. One end of the coke oven gas injection branch pipe is connected to the coke oven gas injection main pipe, and the other end is connected to the coke oven gas injection pipe bank. Each coke oven gas injection pipe bank is provided with a plurality of injection holes.

[0011] An ammonia injection device includes an ammonia injection main pipe, an ammonia injection branch pipe, and an ammonia injection pipe bank. The ammonia injection main pipe is arranged outside the injection hood, and the ammonia injection pipe bank is arranged inside the injection hood and located above the sintering machine trolley. One end of the ammonia injection branch pipe is connected to the ammonia injection main pipe, and the other end is connected to the ammonia injection pipe bank. Each ammonia injection pipe bank is provided with a plurality of injection holes.

[0012] The steam blowing device includes a steam blowing main pipe, a steam blowing branch pipe, and a steam blowing pipe row. The steam blowing main pipe is arranged outside the blowing hood, and the steam blowing pipe row is arranged inside the blowing hood and located above the sintering machine trolley. One end of the steam blowing branch pipe is connected to the steam blowing main pipe, and the other end is connected to the steam blowing pipe row. Multiple blowing holes are set on each steam blowing pipe row.

[0013] Preferably, the coke oven gas injection area is located at a safe distance of one wind box length behind the ignition and holding furnace, covering the effective length L of the sintering machine. 有效 16.67%-38.89% (from head to tail); the ammonia injection coverage area is the effective length L of the sintering machine 有效 38.89%-52.22% of the total length of the sintering machine; the steam injection coverage area is the effective length of the sintering machine L 有效 38.89%-61.11% of the total effective length of the sintering machine is L 有效 38.89%-52.22% of the area is covered by the ammonia and steam coupled injection section.

[0014] Preferably, the coke oven gas injection main pipe, the ammonia injection main pipe, the steam injection main pipe and the corresponding injection branches are all provided with flow meters, flow regulating valves and electric shut-off valves.

[0015] Preferably, the coke oven gas injection branch pipes, the ammonia injection branch pipes and the steam injection branch pipes (4) are arranged in 1-3 rows at equal intervals of 4 m along the length direction of the sintering machine.

[0016] In combination with the above device, a corresponding blowing control method is proposed, which includes the following control steps:

[0017] S1 equipment detection and parameter setting

[0018] An online laser gas analyzer is installed at the wind box branch pipe below the sintering machine trolley to detect the NOx concentration in the sintering flue gas below the ammonia and steam coupled injection section, and to detect the CO concentration below the steam injection section (non-coupled section).

[0019] Determine the total amount of coke oven gas injection control ratio J b (The coke oven gas flow rate required for each ton of sintering mixture is 1.2-3.2m 3 / t), ammonia injection total amount control ratio A b (The required ammonia injection flow rate per ton of sintering mixture is 1.5-3.0m 3 / t), steam injection total amount control ratio Z b (The steam injection flow rate required for each ton of sintering mixture is 2.0-3.0m 3 / t).

[0020] The spatial distance value of the coke oven gas injection branch pipe corresponding to the sintering machine in the length direction is used as a label to control the program to identify the branch pipe.

[0021] S2 automatic control of injection volume

[0022] The control system sets the sintering mixed material quantity according to the value Q mixed material quantity, and calculates the value according to Q mixed material quantity × J b 、Q mixture amount × A b 、Q mixture amount × Z b , automatically controlling the total amount of coke oven gas, ammonia and steam injection, and automatically adjusting the flow of each branch pipe.

[0023] Coke oven gas flow rate of each branch pipe: In the control area, the flow rate of all branches corresponding to every 4m is calculated at 3-7m 3 / hThe total amount of injection is automatically distributed and adjusted with different decreasing amplitudes.

[0024] The flow rate of each branch pipe of ammonia is evenly controlled according to the total amount of ammonia injected.

[0025] The flow rate of each steam branch is evenly controlled according to the total amount of steam injection.

[0026] S3 exception handling

[0027] When the sintering is shut down or the end point of the sintering process is abnormally advanced (the actual end point is greater than 2.5 sintering bellows lengths from the target control position), the NOx concentration value PNOx and CO concentration value PCO of the sintering flue gas obtained by the online laser gas analyzer are eliminated through the discrimination program.

[0028] S4 data collection and sample set construction

[0029] At the feeding position of sintered solid fuel ingredients, the online particle size detection device is used to obtain the composition of each particle size of the sintered solid fuel in real time to obtain the average particle size Mg value.

[0030] Every 30 minutes, the sintering solid fuel ratio Pg, sintering flue gas NOx concentration value PNOx, sintering flue gas CO concentration value PCO, and ammonia injection total amount control ratio A are collected. b , Steam injection total amount control ratio Z b , the average value of Mg in the average particle size of sintered solid fuel.

[0031] The average value of each parameter every 30 minutes is used as sample data to form a historical basic sample data set.

[0032] S5 NOx concentration control and adjustment

[0033] The partial least squares method was used to perform multiple regression analysis on the historical data of sintering flue gas NOx concentration value PNOx and sintering solid fuel ratio Pg, and the relevant formula was obtained.

[0034] Process the historical data of NOx concentration value PNOx in sintering flue gas to obtain the mean value and data range value And the corresponding data interval range value |P NOx |, derive formula A b =(β*P g +CP NOx ) / α (Formula 2).

[0035] Compare the NOx concentration value PNOx of the sintering flue gas in the current 30-minute cycle with the relevant values:

[0036] If satisfied This indicates that the current ammonia flow rate does not increase the NOx concentration, and the program maintains the current A b .

[0037] If satisfied Substitute the PR data of the sintering solid fuel ratio in the current 30-minute period and the corresponding value of 120% of the current sintering flue gas NOx concentration value PNOx into formula 2 to obtain the new value A b ′=(β*P g +C-120%*P NOx ) / α (Formula 5), ​​the total amount of ammonia sprayed is controlled by the ratio A b Adjust to this value.

[0038] S6 CO concentration control and adjustment

[0039] The partial least square method is used to calculate the CO concentration value PCO of sintering flue gas, the sintering solid fuel ratio Pg, the sintering solid fuel average particle size Mg, and the total amount of ammonia injection control ratio A. b , Steam injection total amount control ratio Z b Multiple regression analysis of historical data to obtain relevant formulas

[0040] P CO =α*A b +β*P g +γ*A z +δ*M g +C (Formula 6).

[0041] Process the historical data of CO concentration value PCO of sintering flue gas, obtain the mean value and data range value, and derive the formula Z b =(P CO -α*A b -β*P g -δ*M g -C) / γ(Formula 7).

[0042] Compare the CO concentration value PCO of the sintering flue gas in the current 30-minute cycle with the relevant values:

[0043] If the formula is satisfied It indicates that the current steam flow is appropriate and the program maintains the current Z b .

[0044] If the formula is satisfied The sintering solid fuel ratio PR data and the total ammonia injection control ratio A in the current 30-minute cycle are b And the corresponding value of 120% of the current sintering flue gas CO concentration value PCO value is substituted into formula 2 to obtain the new value

[0045] Z b ′=(115%*P CO -α*A b -β*P g -δ*M g -C) / γ (Formula 10), and adjust the steam injection total amount control ratio Zb to this value.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] Through coupled injection of coke oven gas, ammonia, and steam into the sintering charge, this system achieves the coupled injection of non-carbon-hydrogen-based gas fuels with hydrocarbon-based gas fuels in the sintering process. Simultaneously, the injection rates of coke oven gas, ammonia, and steam are automatically controlled and adjusted within the process control range based on the NOx and CO concentrations in the sintering flue gas, achieving a better coupling effect and effective carbon and emission reduction. Following implementation, the sinter drum strength has increased, the sinter yield has improved, and the solid fuel consumption has decreased year-on-year, significantly improving quality and reducing energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a schematic structural diagram of the coke oven gas injection device, ammonia injection device and steam injection device of the present invention;

[0049] Figure 2 It is a schematic diagram of the structure of the sintering machine trolley and the blowing hood of the present invention.

[0050] In the figure: 1. Coke oven gas injection main pipe; 2. Steam injection main pipe; 3. Coke oven gas injection branch pipe; 4. Steam injection branch pipe; 5. Coke oven gas injection pipe bank; 6. Steam injection pipe bank; 7. Coke oven gas injection main pipe flow meter; 8. Coke oven gas injection main pipe flow regulating valve; 9. Coke oven gas injection main pipe electric shut-off valve; 10. Coke oven gas injection branch pipe flow meter; 11. Coke oven gas injection branch pipe flow regulating valve; 12. Coke oven gas injection branch pipe electric shut-off valve; 13. Steam injection branch pipe flow meter; 14. Steam injection branch pipe flow regulating valve; 15 1. Electric shut-off valve for steam injection branch pipe; 16. Flow meter for steam injection main pipe; 17. Flow regulating valve for steam injection main pipe; 18. Electric shut-off valve for steam injection main pipe; 19. Ammonia injection main pipe; 20. Flow meter for ammonia injection main pipe; 21. Flow regulating valve for ammonia injection main pipe; 22. Electric shut-off valve for ammonia injection main pipe; 23. Ammonia injection branch pipe; 24. Flow meter for ammonia injection branch pipe; 25. Flow regulating valve for ammonia injection branch pipe; 26. Electric shut-off valve for ammonia injection branch pipe; 27. Ammonia injection pipe row; 28. Injection hood; 29. ​​Sintering machine trolley. DETAILED DESCRIPTION

[0051] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the implementation regulations described are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0052] refer to Figure 1-2 A coke oven gas and ammonia steam coupled injection device for a sintering material surface, comprising a sintering machine trolley 29, an injection hood 28, a coke oven gas injection device, an ammonia injection device, and a steam injection device. The coke oven gas injection device comprises a coke oven gas injection main pipe 1, a coke oven gas injection branch pipe 3, and a coke oven gas injection pipe bank 5. The ammonia injection device comprises an ammonia injection main pipe 19, an ammonia injection branch pipe 23, and an ammonia injection pipe bank 27. The steam injection device comprises a steam injection main pipe 2, a steam injection branch pipe 4, and a steam injection pipe bank 6.

[0053] The sintering machine trolley 29 is located within the injection hood 28. The coke oven gas injection main pipe 1, the ammonia injection main pipe 19, and the steam injection main pipe 2 are installed outside the injection hood 28. The coke oven injection pipe bank 5, the ammonia injection pipe bank 27, and the steam injection pipe bank 6 are installed within the injection hood 28 above the sintering machine trolley 29.

[0054] One end of the coke oven injection branch pipe 3 is connected to the coke oven gas injection main pipe 1 and the other end is connected to the coke oven injection pipe row 5, and each coke oven gas injection pipe row 5 is provided with 6-20 injection holes; one end of the ammonia injection branch pipe 23 is connected to the ammonia injection main pipe 19 and the other end is connected to the ammonia injection pipe row 27, and each ammonia injection pipe row 27 is provided with 8-25 injection holes; one end of the steam injection branch pipe 4 is connected to the steam injection main pipe 2 and the other end is connected to the steam injection pipe row 6, and each steam injection pipe row 6 is provided with 6-28 injection holes.

[0055] The aforementioned coke oven gas injection area is generally located at a safe distance of one wind box length behind the ignition and holding furnace. The area covered by coke oven gas injection is set to be within the range of 16.67%-38.89% (from the beginning to the end) of the effective length Leffective of the sintering machine; the area covered by ammonia injection is set to be within the range of 38.89%-52.22% (from the beginning to the end) of the effective length Leffective of the sintering machine; and the area covered by steam injection is set to be within the range of 38.89%-61.11% (from the beginning to the end) of the effective length Leffective of the sintering machine. The range of 38.89%-52.22% (from the beginning to the end) of the effective length Leffective of the sintering machine is the area covered by the ammonia and steam coupled injection section.

[0056] The mechanism of steam injection's impact on the combustion process: When temperatures exceed 674°C, water vapor reacts with coke to produce H2 and CO. H2 reacts with O2 to generate a large number of (OH) and (O) radicals. These (OH) and (O) radicals rapidly oxidize CO to CO2, thus contributing to the reduction in CO emissions. Furthermore, increasing the water vapor injection concentration can improve fuel combustion efficiency. During ammonia-assisted sintering, increasing the additional ammonia injection concentration increases water vapor generation, promoting the conversion of more CO to CO2. Furthermore, within the 500–900°C range, ammonia reacts with nitric oxide (NO) to undergo a redox reaction, reducing CO content. Under ammonia injection conditions, ammonia combustion in the secondary combustion zone produces large amounts of water vapor and NO. Under the combined effects of water vapor and NO, the flue gas CO concentration decreases with increasing ammonia injection concentration during sintering, while fuel combustion efficiency increases.

[0057] The above-mentioned coke oven gas, ammonia main pipes, steam main pipes and injection branches are all equipped with flow meters, flow regulating valves and electric shut-off valves.

[0058] The above-mentioned coke oven gas injection branch pipes, ammonia injection branch pipes and steam injection branch pipes are arranged in 1-3 rows at equal intervals of 4 meters along the length direction of the sintering machine.

[0059] There are multiple bellows under the sintering machine trolley. An online laser gas analyzer is installed at the sintering bellows branch pipe below the ammonia and steam coupled injection section, which is used to detect the NOx concentration in the sintering flue gas in real time. An online laser gas analyzer is also installed at the sintering bellows branch pipe below the steam injection section (non-ammonia and steam coupled injection section), which is used to detect the CO concentration in the sintering flue gas in real time.

[0060] The spatial distance values ​​of the above-mentioned coke oven gas injection branch pipes corresponding to the length direction of the sintering machine are used as labels to control the effective identification of the first row to the last row of branch pipes by the program.

[0061] Coke oven gas injection total amount control ratio J b The coke oven gas flow rate required for each ton of sintering mixture is in the range of 1.2-3.2m3 / t.

[0062] Ammonia injection total amount control ratio A b The ammonia flow rate required for injection per ton of sintering mixture is in the range of 1.5-3.0m3 / t.

[0063] Steam injection total amount control ratio Z b It is the steam injection flow rate required for each ton of sintering mixture, and its value range is 2.0-3.0m3 / t.

[0064] The sintering machine is equipped with a control system. The control system automatically controls the injection amount of coke oven gas, ammonia and steam according to the sintering mixed material setting value Qmixed material, and automatically adjusts the flow of each branch pipe according to the total amount. At the same time, according to the sintering NOx and CO concentration values ​​detected in real time by the online laser gas analyzer, and combined with the sintering solid fuel ratio value, solid fuel particle size detection value, and ammonia injection total amount control ratio A, the control system automatically adjusts the flow of each branch pipe according to the total amount. b and steam injection total amount control ratio Z b Iterative regression of historical data is used to control the total amount of ammonia injection ratio A b and steam injection total amount control ratio Z b Closed-loop automatic adjustment within the above control range is performed to achieve optimal levels of sintering NOx and CO concentrations.

[0065] The total amount of coke oven gas, ammonia and steam injection is linked to the set value of the total amount of sintering mixture Q mixture amount, that is, the total amount of coke oven gas injection is controlled by Q mixture amount × J b Automatic control is carried out, and the total amount of ammonia injection is controlled by Q mixed material amount × A b Automatic control is carried out, and the total amount of steam injection is controlled by Q mixed material amount × Z b Perform automatic control.

[0066] The above-mentioned branch flow rates of the coke oven gas are automatically distributed and adjusted according to the coke oven gas and the total amount of injection is adjusted according to the different decreasing rates of 3-7m3 / h for all branch flow rates within the control area corresponding to every 4m.

[0067] The flow rates of the above-mentioned ammonia branch pipes are evenly controlled according to the total amount of ammonia injection.

[0068] The flow rates of the above-mentioned steam branches are evenly controlled according to the total amount of steam injection.

[0069] When the sintering is shut down or the end point of the sintering process is abnormally advanced, and when the end point of the sintering is abnormally advanced (the actual end point is greater than the length of 2.5 sintering bellows compared to the target control position of the sintering end point), the NOx concentration value PNOx and CO concentration value PCO of the sintering flue gas obtained by the above-mentioned online laser gas analyzer are eliminated through the setting of the judgment program.

[0070] An online particle size detection device is provided at the feeding position of the sintered solid fuel ingredients, which can obtain the particle size composition of the sintered solid fuel in real time, and thereby obtain the average particle size Mg value of the sintered solid fuel.

[0071] Obtain the sintering solid fuel ratio Pg, the sintering flue gas NOx concentration value PNOx, the sintering flue gas CO concentration value PCO, and the ammonia injection total amount control ratio A within 30 minutes of the sintering process b , Steam injection total amount control ratio Z b , the average value corresponding to the average particle size Mg of sintered solid fuel.

[0072] Furthermore, the average value of each of the above parameters in every 30-minute period is taken as one sample data to form a historical basic sample data set.

[0073] The partial least squares method is used to perform multiple regression analysis on the historical data of the sintering flue gas NOx concentration value PNOx and the sintering solid fuel ratio Pg, and the following formula can be obtained.

[0074]

[0075] Where: PNOx is the NOx concentration in sintering flue gas, ppm; A b is the ammonia flow rate required for each ton of sintering mixture, m3 / t; Pg is the ratio of sintering solid fuel, %; and are regression coefficients; C is a constant term.

[0076] Furthermore, the historical data of the sintering flue gas NOx concentration value PNOx are processed to obtain the corresponding mean value and the corresponding data interval range value.

[0077] From the above formula 1, we can deduce

[0078] A b =(β*P g +CP NOx ) / α Formula 2

[0079] Compare the current 30-minute cycle sintering flue gas NOx concentration value PNOx with

[0080]

[0081] When it is established, it means that the flow rate of ammonia injected into the sintering material surface does not cause the increase of NOx concentration in the sintering flue gas, and the program control maintains the current A b

[0082] If the current 30-min period sintering flue gas NOx concentration value PNOx is compared with

[0083]

[0084] When it is established, the sintering solid fuel ratio PR data in the current 30-minute cycle and the corresponding value of 120% of the sintering flue gas NOx concentration value PNOx in the current 30-minute cycle are substituted into the above formula 2 to obtain the value, that is,

[0085] A b ′=(β*P g +C-120%*P NOx ) / α Formula 5

[0086] Furthermore, the total amount of ammonia sprayed is controlled at a ratio of A. b Adjust to value A b ’ for control.

[0087] The partial least squares method is used to calculate the CO concentration value PCO of the sintering flue gas, the sintering solid fuel ratio Pg, the average particle size Mg of the sintering solid fuel, and the total amount of ammonia injection control ratio A. b , Steam injection total amount control ratio Z b The following formula can be obtained by performing multiple regression analysis on the historical data.

[0088] P CO =α*A b +β*P g +γ*A z +δ*M g +C Formula 6

[0089] Where: PCO is the CO concentration in sintering flue gas, ppm; A b is the ammonia flow rate required for each ton of sintering mixture, m3 / t; Z bis the steam injection flow rate required for each ton of sintering mixture, m3 / t; Pg is the proportion of sintering solid fuel, %; Mg is the average particle size of sintering solid fuel, mm; α, β, γ are all regression coefficients; C is a constant term.

[0090] Furthermore, the historical data of the sintering flue gas CO concentration value PCO are processed to obtain the corresponding mean value and the corresponding data interval range value.

[0091] From the above formula 6, we can deduce

[0092] Z b =(P CO -α*A b -β*P g -δ*M g -C) / γ Equation 7

[0093] Compare the current 30-minute cycle sintering flue gas CO concentration value PCO with

[0094]

[0095] When it is established, it means that the current flow rate of steam injection on the sintering material surface is more appropriate, and the program control maintains the current Z b

[0096] If the current 30-min period sintering flue gas CO concentration value PCO is compared with

[0097]

[0098] When established, the sintering solid fuel ratio PR data and the total ammonia injection control ratio A in the current 30-minute cycle are b And the corresponding value of 120% of the current 30-min period sintering flue gas CO concentration value PCO value is substituted into the above formula 2 to obtain Z b ′ value, that is

[0099] Z b ′=(115%*P CO -α*A b -β*P g -δ*M g -C) / γ Equation 10

[0100] Furthermore, at this time, the total amount of steam injection is controlled at the ratio Z b Adjust to value Z b ’ for control.

[0101] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A sintering material surface coke oven gas and ammonia steam coupled injection device, characterized in that: include Sintering machine trolley; Blowing hood, the sintering machine trolley is located inside the blowing hood; A coke oven gas injection device comprises a coke oven gas injection main pipe (1), a coke oven gas injection branch pipe (3), and a coke oven gas injection pipe row (5). The coke oven gas injection main pipe (1) is arranged outside the injection hood, the coke oven gas injection pipe row (5) is arranged inside the injection hood and located above the sintering machine trolley, one end of the coke oven gas injection branch pipe (3) is connected to the coke oven gas injection main pipe (1), and the other end is connected to the coke oven gas injection pipe row (5), and each coke oven gas injection pipe row (5) is provided with a plurality of injection holes; An ammonia gas injection device comprises an ammonia gas injection main pipe (19), an ammonia gas injection branch pipe (23), and an ammonia gas injection pipe row (27). The ammonia gas injection main pipe (19) is arranged outside the injection hood, and the ammonia gas injection pipe row (27) is arranged inside the injection hood and located above the sintering machine trolley. One end of the ammonia gas injection branch pipe (23) is connected to the ammonia gas injection main pipe (19), and the other end is connected to the ammonia gas injection pipe row (27). Each ammonia gas injection pipe row (27) is provided with a plurality of injection holes. The steam injection device comprises a steam injection main pipe (2), a steam injection branch pipe (4), and a steam injection pipe row (6). The steam injection main pipe (2) is arranged outside the injection cover, the steam injection pipe row (6) is arranged inside the injection cover and located above the sintering machine trolley, one end of the steam injection branch pipe (4) is connected to the steam injection main pipe (2), and the other end is connected to the steam injection pipe row (6), and each steam injection pipe row (6) is provided with a plurality of injection holes.

2. The sintering surface coke oven gas and ammonia steam coupled injection device according to claim 1, characterized in that: The coke oven gas injection area is located at a safe distance of one wind box length behind the ignition and holding furnace, covering the effective length L of the sintering machine. 有效 16.67%-38.89% (from head to tail); the ammonia injection coverage area is the effective length L of the sintering machine 有效 38.89%-52.22% of the total length of the sintering machine; the steam injection coverage area is the effective length of the sintering machine L 有效 38.89%-61.11% of the total effective length of the sintering machine is L 有效 38.89%-52.22% of the area is covered by the ammonia and steam coupled injection section.

3. The sintering surface coke oven gas and ammonia steam coupled injection device according to claim 2, characterized in that: The coke oven gas injection main pipe (1), the ammonia injection main pipe (19), the steam injection main pipe (2) and the corresponding injection branch pipes (3, 23, 4) are all provided with flow meters (7, 20, 16, 10, 24, 13), flow regulating valves (8, 21, 17, 11, 25, 14) and electric shut-off valves (9, 22, 18, 12, 26, 15).

4. The sintering surface coke oven gas and ammonia steam coupled injection device according to claim 3, characterized in that: Coke oven gas injection branch pipes (3), ammonia injection branch pipes (23) and steam injection branch pipes (4) are arranged in 1-3 rows at equal intervals of 4 meters along the length direction of the sintering machine.

5. A method for controlling the coupled injection of coke oven gas and ammonia steam at a sintering surface, the method being based on the coupled injection device for coke oven gas and ammonia steam at a sintering surface according to any one of claims 1 to 4, characterized in that: The control steps include: S1 equipment detection and parameter setting An online laser gas analyzer is installed at the wind box branch pipe below the sintering machine trolley to detect the NOx concentration in the sintering flue gas below the ammonia and steam coupled injection section, and to detect the CO concentration below the steam injection section (non-coupled section). Determine the total amount of coke oven gas injection control ratio J b (The coke oven gas flow rate required for each ton of sintering mixture is 1.2-3.2m 3 / t), ammonia injection total amount control ratio A b (The required ammonia injection flow rate per ton of sintering mixture is 1.5-3.0m 3 / t), steam injection total amount control ratio Z b (The steam injection flow rate required for each ton of sintering mixture is 2.0-3.0m 3 / t). The spatial distance value of the coke oven gas injection branch pipe corresponding to the sintering machine in the length direction is used as a label to control the program to identify the branch pipe. S2 automatic control of injection volume The control system sets the sintering mixed material quantity according to the value Q mixed material quantity, and calculates the value according to Q mixed material quantity × J b 、Q mixture amount × A b 、Q mixture amount × Z b , automatically controlling the total amount of coke oven gas, ammonia and steam injection, and automatically adjusting the flow of each branch pipe. Coke oven gas flow rate of each branch pipe: In the control area, the flow rate of all branches corresponding to every 4m is calculated at 3-7m 3 / hThe total amount of injection is automatically distributed and adjusted with different decreasing amplitudes. The flow rate of each branch pipe of ammonia is evenly controlled according to the total amount of ammonia injected. The flow rate of each steam branch is evenly controlled according to the total amount of steam injection. S3 exception handling When the sintering is shut down or the end point of the sintering process is abnormally advanced (the actual end point is greater than 2.5 sintering bellows lengths from the target control position), the NOx concentration value PNOx and CO concentration value PCO of the sintering flue gas obtained by the online laser gas analyzer are eliminated through the discrimination program. S4 data collection and sample set construction At the feeding position of sintered solid fuel ingredients, the online particle size detection device is used to obtain the composition of each particle size of the sintered solid fuel in real time to obtain the average particle size Mg value. Every 30 minutes, the sintering solid fuel ratio Pg, sintering flue gas NOx concentration value PNOx, sintering flue gas CO concentration value PCO, and ammonia injection total amount control ratio A are collected. b , Steam injection total amount control ratio Z b , the average value of Mg in the average particle size of sintered solid fuel. The average value of each parameter every 30 minutes is used as sample data to form a historical basic sample data set. S5 NOx concentration control and adjustment The partial least squares method was used to perform multiple regression analysis on the historical data of sintering flue gas NOx concentration value PNOx and sintering solid fuel ratio Pg, and the relevant formula was obtained. Process the historical data of NOx concentration value PNOx in sintering flue gas to obtain the mean value and data range value And the corresponding data interval range value |P NOx |, derive formula A b =(β*P g +CP NOx ) / α(Formula 2). Compare the NOx concentration value PNOx of the sintering flue gas in the current 30-minute cycle with the relevant values: If satisfied This indicates that the current ammonia flow rate does not increase the NOx concentration, and the program maintains the current A b . If satisfied Substitute the PR data of the sintering solid fuel ratio in the current 30-minute period and the corresponding value of 120% of the current sintering flue gas NOx concentration value PNOx into formula 2 to obtain the new value A b ′=(β*P g +C-120%*P NOx ) / α (Formula 5), ​​the total amount of ammonia sprayed is controlled by the ratio A b Adjust to this value. S6 CO concentration control and adjustment The partial least square method is used to calculate the CO concentration value PCO of sintering flue gas, the sintering solid fuel ratio Pg, the sintering solid fuel average particle size Mg, and the total amount of ammonia injection control ratio A. b , Steam injection total amount control ratio Z b Multiple regression analysis of historical data to obtain relevant formulas P CO = α * A b + β * P g + γ * A z + δ * M g + C (Equation 6). Process the historical data of CO concentration value PCO of sintering flue gas, obtain the mean value and data range value, and derive the formula Z b =(P CO -α*A b -β*P g -δ*M g -C) / γ(Formula 7). Compare the CO concentration value PCO of the sintering flue gas in the current 30-minute cycle with the relevant values: If the formula is satisfied It indicates that the current steam flow is appropriate and the program maintains the current Z b . If the formula is satisfied The sintering solid fuel ratio PR data and the total ammonia injection control ratio A in the current 30-minute cycle are b And the corresponding value of 120% of the current sintering flue gas CO concentration value PCO value is substituted into formula 2 to obtain the new value Z b ′=(115%*P CO -α*A b -β*P g -δ*M g -C) / γ (Formula 10), and adjust the steam injection total amount control ratio Zb to this value.

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