Method for controlling abnormality of ultra-low emission of pollutants of lime kiln

Abstract

The present application relates to a kind of control lime kiln pollutant ultra-low emission abnormality method, the method includes two cases including the treatment method of appearing pollutant ultra-low emission abnormality and the treatment method of dust filter bag dust accumulation, this scheme adjusts parameter in advance, improves waste gas emission standard, reduces pollution to atmosphere, reduces the influence to product yield and quality: utilize the double-acting force of filter bag top nozzle in turn cyclic spray and the knock of flexible hammer rotation to filter bag, can effectively remove filter bag dust accumulation, prevent filter bag material, thereby reduce the emission of pollutant, while prolong the service life of filter bag.

Description

Technical Field

[0001] This invention relates to a method, specifically a method for controlling abnormal ultra-low emissions of pollutants from lime kilns, belonging to the field of lime kiln production technology and automatic control technology. Background Technology

[0002] Modern large-scale production often comes with the risk of environmental pollution, a significant issue in the process of industrialization. As global environmental problems worsen, businesses and governments are placing increasing emphasis on environmental protection. Environmental monitoring data from enterprise production processes is directly connected to government monitoring platforms and subject to government oversight. If particulate matter emissions from a lime kiln are abnormal, the government's online monitoring indicators are calculated based on the oxygen content in the emitted flue gas. If the measured particulate matter concentration is within acceptable limits, but abnormal oxygen content causes the calculated particulate matter concentration to exceed 10 mg / m³, then... 3 This will affect the compliance rate of enterprises with organized ultra-low emissions and the government's supervision and assessment of enterprises. Summary of the Invention

[0003] This invention addresses the technical problems existing in the prior art by providing a control technology for abnormal ultra-low emissions of pollutants from lime kilns. This technical solution achieves compliant emissions when lime kiln pollutant emissions exceed ultra-low emission standards through process control measures. When particulate matter emissions from lime kilns are abnormal during production, enterprises monitor the measured values ​​of pollutant content, while government online monitoring uses indicators calculated from the oxygen content in the emitted flue gas (conversion concentration formula is shown in Formula 1). If the measured particulate matter concentration does not exceed the standard, but the abnormal oxygen content causes the converted particulate matter concentration to exceed 10 mg / m³, the problem is addressed. 3 This will affect the compliance rate of enterprises with organized ultra-low emissions and the government's supervision and assessment of enterprises.

[0004] Formula for calculating the concentration of particulate matter in lime kilns:

[0005] T 折算 =(K1-K2) / (K1-K3)×K4 Formula 1

[0006] in:

[0007] T 折算 Conversion concentration of particulate matter, mg / m³ 3 ;

[0008] K1: Baseline oxygen content in ambient atmosphere, 21%;

[0009] K2: The baseline oxygen content of the kiln under normal conditions, 8%;

[0010] K3: Measured oxygen content in flue gas, %;

[0011] K4: Measured atmospheric particulate matter emission concentration, mg / m³ 3 .

[0012] To achieve the above objectives, the technical solutions of the present invention include technologies for handling abnormal ultra-low emissions of pollutants and for treating dust accumulation in dust collector filter bags.

[0013] 1. Pollutant Ultra-Low Emission Abnormal Treatment Technology

[0014] The process involves periodic calculations, gradually adjusting parameters such as the frequency of the kiln dust collector fan and the supply of combustion air, with the treatment cycle ranging from 2.5 hours to 6 hours, until T... 折算 At (4.5mg / m 3 7.5 mg / m 3 When the emission level falls within the specified range, stop calculating and adjusting parameters such as the frequency of the kiln dust collector fan and the supply of combustion air (the ultra-low emission standard for particulate matter concentration is <10mg / m³). 3 However, we need to set the ultra-low emission concentration of pollutants to a safer range.

[0015] The calculation method is as follows:

[0016] (1) When T 折算 Within the range (6.0, 8.0) and T 实测 When in the range (0, 2.9)

[0017] Take the following steps:

[0018] 1) Reduce the frequency of the kiln dust collector fan:

[0019] FanFreq i =FanFreq i-1 Formula 2: *(1-η*cos(t / 2T1*π))

[0020] Among them, FanFreq i FanFreq represents the fan frequency of the kiln dust collector at time i. i-1 The frequency of the fan in the kiln dust removal system at time i-1 is represented, t is the time difference from the start of the timer when the concentration of abnormal particulate matter was calculated to the current time, T1 is the set processing time (2.5h, 6h), and η takes values ​​(0.211, 0.219).

[0021] 2) Reduce the supply of combustion air:

[0022] ComAir i =ComAir i-1 Formula 3: *(1-θ*cos(t / 2T1*π))

[0023] ComAir iComAir represents the amount of combustion air at time i. i-1 The amount of combustion air at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was processed to the current time, T1 is the set processing time (2.5h, 6h), and θ takes values ​​(0.201, 0.209).

[0024] 3) Increase gas usage:

[0025] Gas i =Gas i-1 Formula 4: *(1+§cos(t / 2T1*π))

[0026] Gas i Gas represents the amount of gas used at time i. i-1 This represents the amount of gas used at time i-1, t is the time difference from the start of the timer when the concentration of particulate matter was calculated from the point of the abnormality to the current time, T1 is the set processing time (2.5h, 6h), and § takes values ​​of (0.018, 0.021).

[0027] 4) Adjust the drive air pressure:

[0028] DrvAir i =DrvAir i-1 Formula 5: *(1-δ*cos(t / 2T1*π))

[0029] Among them, DrvAir i DrvAir represents the driving air pressure at time i. i-1 The driving air pressure at time i-1 is represented, t is the time difference from the start of the timer from the start of the timer to the current time when the concentration of abnormal particulate matter was calculated, T1 is the set processing time (2.5h, 6h), and δ takes values ​​of (0.241, 0.249).

[0030] (2) When T 折算 Within the range (6.0, 8.0) and T 实测 When in the range (3.0, 5.8)

[0031] Take the following steps:

[0032] 1) Reduce the frequency of the kiln dust collector fan:

[0033] FanFreq i =FanFreq i-1 Formula 6: *(1-η*cos(t / 2T1*π))

[0034] Among them, FanFreq i FanFreq represents the fan frequency of the kiln dust collector at time i.i-1 The frequency of the fan in the kiln dust removal system at time i-1 is represented, t is the time difference from the start of the timer when the concentration of abnormal particulate matter was calculated to the current time, T1 is the set processing time (2.5h, 6h), and η takes values ​​(0.221, 0.229).

[0035] 2) Reduce the supply of combustion air:

[0036] ComAir i =ComAir i-1 Formula 7: *(1-θ*cos(t / 2T1*π))

[0037] ComAir i ComAir represents the amount of combustion air at time i. i-1 The amount of combustion air at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was processed to the current time, T1 is the set processing time (2.5h, 6h), and θ takes values ​​(0.211, 0.219).

[0038] 3) Increase gas usage:

[0039] Gas i =Gas i-1 Formula 8: *(1+§cos(t / 2T1*π))

[0040] Gas i Gas represents the amount of gas used at time i. i-1 This represents the amount of gas used at time i-1, t is the time difference from the start of the timer when the concentration of particulate matter was calculated from the point of the abnormality to the current time, T1 is the set processing time (2.5h, 6h), and § takes values ​​(0.021, 0.024).

[0041] 4) Adjust the drive air pressure:

[0042] DrvAir i =DrvAir i-1 Formula Nine: *(1-δ*cos(t / 2T1*π))

[0043] Among them, DrvAir i DrvAir represents the driving air pressure at time i. i-1 The driving air pressure at time i-1 is represented, t is the time difference from the start of the timer from the start of the timer to the current time when the concentration of abnormal particulate matter was processed, T1 is the set processing time (2.5h, 6h), and δ takes values ​​of (0.251, 0.259).

[0044] (3) When T 折算Within the range (6.0, 8.0) and T 实测 When in the range (5.9,10)

[0045] Take the following steps:

[0046] 1) Reduce the frequency of the kiln dust collector fan:

[0047] FanFreq i =FanFreq i-1 Formula 10: *(1-η*cos(t / 2T1*π))

[0048] Among them, FanFreq i FanFreq represents the fan frequency of the kiln dust collector at time i. i-1 The frequency of the fan in the kiln dust removal system at time i-1 is represented, t is the time difference from the start of the timer when the concentration of abnormal particulate matter was calculated to the current time, T1 is the set processing time (2.5h, 6h), and η takes values ​​(0.231, 0.239).

[0049] 2) Reduce the supply of combustion air:

[0050] ComAir i =ComAir i-1 Formula Eleven: *(1-θ*cos(t / 2T1*π))

[0051] ComAir i ComAir represents the amount of combustion air at time i. i-1 The amount of combustion air at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was processed to the current time, T1 is the set processing time (2.5h, 6h), and θ takes values ​​(0.221, 0.229).

[0052] 3) Increase gas usage:

[0053] Gas i =Gas i-1 Formula XII: *(1+§cos(t / 2T1*π))

[0054] Gas i Gas represents the amount of gas used at time i. i-1 This represents the amount of gas used at time i-1, t is the time difference from the start of the timer when the concentration of particulate matter was calculated from the point of the abnormality to the current time, T1 is the set processing time (2.5h, 6h), and § takes values ​​of (0.025, 0.028).

[0055] 4) Adjust the drive air pressure:

[0056] DrvAir i =DrvAir i-1 Formula Thirteen: *(1-δ*cos(t / 2T1*π))

[0057] Among them, DrvAir i DrvAir represents the driving air pressure at time i. i-1 The driving air pressure at time i-1 is represented, t is the time difference from the start of the timer from the start of the timer to the current time when the concentration of abnormal particulate matter was processed, T1 is the set processing time (2.5h, 6h), and δ takes values ​​of (0.261, 0.269).

[0058] (4) When T 折算 Within the range (8.1, 10.0) and T 实测 When in the range (0, 2.9)

[0059] Take the following steps:

[0060] 1) Reduce the frequency of the kiln dust collector fan:

[0061] FanFreq i =FanFreq i-1 Formula Fourteen: *(1-η*cos(t / 2T1*π))

[0062] Among them, FanFreq i FanFreq represents the fan frequency of the kiln dust collector at time i. i-1 The frequency of the fan in the kiln dust removal system at time i-1 is represented, t is the time difference from the start of the timer when the concentration of abnormal particulate matter was calculated to the current time, T1 is the set processing time (2.5h, 6h), and η takes values ​​(0.241, 0.249).

[0063] 2) Reduce the supply of combustion air:

[0064] ComAir i =ComAir i-1 Formula Fifteen: *(1-θ*cos(t / 2T1*π))

[0065] ComAir i ComAir represents the amount of combustion air at time i. i-1 The amount of combustion air at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was processed to the current time, T1 is the set processing time (2.5h, 6h), and θ takes values ​​(0.231, 0.239).

[0066] 3) Increase gas usage:

[0067] Gasi =Gas i-1 Formula Sixteen: *(1+§cos(t / 2T1*π))

[0068] Gas i Gas represents the amount of gas used at time i. i-1 This represents the amount of gas used at time i-1, t is the time difference from the start of the timer when the concentration of particulate matter was calculated from the point of the abnormality to the current time, T1 is the set processing time (2.5h, 6h), and § takes values ​​(0.029, 0.032).

[0069] 4) Adjust the drive air pressure:

[0070] DrvAir i =DrvAir i-1 Formula 17: *(1-δ*cos(t / 2T1*π))

[0071] Among them, DrvAir i DrvAir represents the driving air pressure at time i. i-1 The driving air pressure at time i-1 is represented, t is the time difference from the start of the timer from the start of the timer to the current time when the concentration of abnormal particulate matter was processed, T1 is the set processing time (2.5h, 6h), and δ takes values ​​of (0.271, 0.279).

[0072] (5) When T 折算 Within the range (8.1, 10.0) and T 实测 When in the range (3.0, 5.8)

[0073] Take the following steps:

[0074] 1) Reduce the frequency of the kiln dust collector fan:

[0075] FanFreq i =FanFreq i-1 Formula 18: *(1-η*cos(t / 2T1*π))

[0076] Among them, FanFreq i FanFreq represents the fan frequency of the kiln dust collector at time i. i-1 The frequency of the fan in the kiln dust removal system at time i-1 is represented, t is the time difference from the start of the timer when the concentration of abnormal particulate matter was calculated to the current time, T1 is the set processing time (2.5h, 6h), and η takes values ​​(0.251, 0.259).

[0077] 2) Reduce the supply of combustion air:

[0078] ComAir i=ComAir i-1 Formula 19: *(1-θ*cos(t / 2T1*π))

[0079] ComAir i ComAir represents the amount of combustion air at time i. i-1 The amount of combustion air at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was processed to the current time, T1 is the set processing time (2.5h, 6h), and θ takes values ​​(0.241, 0.249).

[0080] 3) Increase gas usage:

[0081] Gas i =Gas i-1 Formula 20: *(1+§cos(t / 2T1*π))

[0082] Gas i Gas represents the amount of gas used at time i. i-1 This represents the amount of gas used at time i-1, t is the time difference from the start of the timer when the concentration of particulate matter was calculated from the point of the abnormality to the current time, T1 is the set processing time (2.5h, 6h), and § takes values ​​of (0.033, 0.036).

[0083] 4) Adjust the drive air pressure:

[0084] DrvAir i =DrvAir i-1 Formula 21: *(1-δ*cos(t / 2T1*π))

[0085] Among them, DrvAir i DrvAir represents the driving air pressure at time i. i-1 The driving air pressure at time i-1 is represented, t is the time difference from the start of the timer from the start of the timer to the current time when the concentration of abnormal particulate matter was processed, T1 is the set processing time (2.5h, 6h), and δ takes values ​​of (0.281, 0.289).

[0086] (6) When T 折算 Within the range (8.1, 10.0) and T 实测 When in the range (5.9,10)

[0087] Take the following steps:

[0088] 1) Reduce the frequency of the kiln dust collector fan:

[0089] FanFreq i =FanFreq i-1Formula 22: *(1-η*cos(t / 2T1*π))

[0090] Among them, FanFreq i FanFreq represents the fan frequency of the kiln dust collector at time i. i-1 The frequency of the fan in the kiln dust removal system at time i-1 is represented, t is the time difference from the start of the timer when the concentration of abnormal particulate matter was calculated to the current time, T1 is the set processing time (2.5h, 6h), and η takes values ​​(0.261, 0.269).

[0091] 2) Reduce the supply of combustion air:

[0092] ComAir i =ComAir i-1 Formula 23: *(1-θ*cos(t / 2T1*π))

[0093] ComAir i ComAir represents the amount of combustion air at time i. i-1 The amount of combustion air at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was calculated to the current time, T1 is the set processing time (2.5h, 6h), and θ takes values ​​(0.251, 0.259).

[0094] 3) Increase gas usage:

[0095] Gas i =Gas i-1 Formula 24: *(1+§cos(t / 2T1*π))

[0096] Gas i Gas represents the amount of gas used at time i. i-1 This represents the amount of gas used at time i-1, t is the time difference from the start of the timer when the concentration of particulate matter was calculated from the point of the abnormality to the current time, T1 is the set processing time (2.5h, 6h), and § takes values ​​of (0.037, 0.042).

[0097] 4) Adjust the drive air pressure:

[0098] DrvAir i =DrvAir i-1 Formula 25: *(1-δ*cos(t / 2T1*π))

[0099] Among them, DrvAir i DrvAir represents the driving air pressure at time i. i-1The driving air pressure at time i-1 is represented, t is the time difference from the start of the timekeeping from the time of the calculated concentration of abnormal particulate matter to the current time, T1 is the set processing time (2.5h, 6h), and δ takes values ​​of (0.281, 0.288).

[0100] 2. Dust Collection Filter Bag Dust Accumulation Treatment Technology

[0101] The lime production process generates a large amount of waste, and the exhaust gas contains a significant amount of dust. Dust removal is primarily achieved through dust collector filter bags. However, during the dust removal process, a large amount of dust adheres to the outer surface of the filter bags, affecting their dust removal efficiency. To effectively remove the accumulated dust from the filter bags, thereby ensuring dust removal efficiency and extending their service life, the following improvement measures are proposed:

[0102] (1) Add pulse nozzles: Three evenly distributed nozzles are set on the top of each filter bag, with a nozzle diameter of D. 喷嘴 The nozzle length is L 喷嘴 It is used to spray compressed air, with the nozzle making an angle α with the vertical direction and the compressed air pressure being P. During each pulse spray, three nozzles spray sequentially in a cyclical manner.

[0103] (2) New Flexible Hammers: Each filter bag has a motor-driven metal rod in the middle, on which four spherical flexible hammers are installed. The included angle between the horizontal projections of the four flexible hammers is 90 degrees, and the spacing between the flexible hammers is L. The hammers are made of high-temperature resistant flexible polyimide aerogel (PIAs). The connection between the metal rod and the hammer handle is a movable link, and the length of the hammer handle is L. 锤柄 =0.8*D 滤袋 (D 滤袋 (Filter bag diameter), the diameter of the flexible hammer is D. 柔性锤 The flexible hammer rotates at a speed of n. The centripetal force of the hammer during rotation raises the height of the flexible hammer, thereby striking the filter bag.

[0104] (3) The flexible hammer and nozzle work simultaneously, with a working cycle of T. 工作 The flexible hammer begins to rotate, and simultaneously, the three nozzles operate at intervals of t. 喷嘴 The pulse valve performs sequential cyclic blowing for a duration of t. 持续 until the flexible hammer stops rotating; (see Figure 1 , Figure 2 )

[0105] (4) The motor drives the metal rod to rotate, which in turn drives the flexible hammer to make a circular motion. The centripetal force of the hammer rotation raises the height of the flexible hammer, thereby striking the filter bag. At the same time, the force generated by the compressed air sprayed from the pulse nozzle on the filter bag is added, thereby effectively removing the dust accumulated in the filter bag.

[0106] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Adjusting parameters in advance improves exhaust emission standards and reduces air pollution: T converted to exceed 10mg / m³ 3 When T is within the range of (4.5, 7.5), the system will alarm the government's air monitoring platform. This invention will start adjusting parameters such as the frequency of the kiln dust removal fan, the amount of combustion air, the amount of gas used, and the driving air when T is within the range of (4.5, 7.5) to avoid or reduce pollution emissions and indirectly improve the exhaust emission standards.

[0107] 2. Slowly adjust parameters to reduce the impact on product output and quality: By using the trigonometric function method, parameters such as the frequency of the kiln dust removal fan, combustion air, gas consumption, and driving air are slowly adjusted to avoid affecting the output and quality of the product (lime) due to parameter adjustments. At the same time, it also avoids affecting the service life of the equipment (drastic changes in equipment operating parameters will accelerate equipment wear) and the effective supply of combustion air, gas consumption, and driving air.

[0108] 3. Utilizing the combined force of sequential cyclic blowing from the nozzles at the top of the filter bag and the impact of the rotating flexible hammer, dust accumulation on the filter bag is effectively removed, preventing material buildup and thus reducing pollutant emissions while extending the filter bag's lifespan. 4. Avoiding production shutdowns for maintenance due to dust emissions exceeding ultra-low emission standards, thereby increasing output: Existing technology achieves dust emissions > 9.5 mg / m³ (converted to T). 3 Production was previously shut down for maintenance. This invention enables online automatic adjustment, avoiding production losses caused by shutdowns for maintenance. According to statistics, before the implementation of this technology (in 2023), the four lime kilns at Meigang Steel suffered from T-conversion >9.5mg / m³. 3 This resulted in 10 production shutdowns for maintenance, with a monthly output of 56,223 tons. The dust collector filter bag lifespan was 14 months. During the experimental phase of this technology (2024), four lime kilns at Meigang Steel experienced dust concentrations exceeding 9.5 mg / m³. 3 The technology resulted in zero production stoppages and maintenance, with a monthly output of 57,356 tons and a dust collector filter bag lifespan of 16 months. After adopting this technology, the number of production stoppages and maintenance decreased by 10, the average output increased by 1,133 tons per month (57,356 tons / month - 56,223 tons / month), and the dust collector filter bag lifespan increased by 2 months. This has created considerable economic and social benefits.

[0109] 5. Improved economic efficiency:

[0110] 1) Due to the improved ultra-low emission compliance rate, enterprises enjoy a certain tax exemption from the government. If any pollutant exceeds the online effective hourly data standard in a certain month, the company will not be eligible for environmental protection tax reduction for any of its air and water discharge outlets and pollutants for that month, and will not be able to enjoy the preferential policy of emission concentration discount. Since there were 3 instances of non-compliance with ultra-low emission standards in 2023, the company could not enjoy the government's tax exemption amount = 180,000 yuan / time (tax exemption amount per instance) * 3 times / year = 540,000 yuan / year. In 2024, there were 0 instances of non-compliance with ultra-low emission standards, and the company enjoyed an additional 540,000 yuan / year in government tax exemption compared to 2023.

[0111] 2) Based on point 4 above, the use of this technology increases lime production and brings certain economic benefits;

[0112] 3) Based on the above 4, the use of this technology will reduce the number of downtime maintenance, reduce maintenance costs, and improve economic efficiency;

[0113] 4) Based on the above 4, the use of this technology increases the lifespan of dust collector filter bags, bringing certain economic benefits; Attached Figure Description

[0114] Figure 1 Cross-sectional view of filter bag (nozzle, flexible hammer).

[0115] Figure 2 Horizontal projection of the nozzle. Detailed Implementation

[0116] To enhance understanding of the present invention, detailed descriptions are provided below in conjunction with embodiments.

[0117] Example 1:

[0118] During the experimental phase, taking the lime production at Meigang No. 1 lime kiln (500T sleeve kiln) in April 2025 as an example, the fuel gas used had a calorific value of 1960 Kcal / m³. 3 The high-coke mixed gas has a kiln dust removal fan frequency of 38Hz and a combustion air volume of 960m³ / h. 3 / h, gas consumption is 8500m³ 3 / h, driving air pressure is 40kPa, and the online monitoring instrument shows that the measured atmospheric particulate matter emission concentration at the kiln dust removal exhaust outlet is 3.26mg / m³. 3 The calculated particulate matter emission concentration is 7.25 mg / m³. 3 .

[0119] The parameters are explained below:

[0120] 1. The measured atmospheric particulate matter emission concentration at the kiln dust removal exhaust outlet was 3.26 mg / m³. 3 The converted atmospheric particulate matter emission concentration is

[0121] 7.25mg / m 3 Since T exceeds (4.5 mg / m²) 3 7.5 mg / m 3 The safe concentration range for lime kiln No. 1 is <6.5 mg / m³. 3 The system determines the severity of the abnormal ultra-low emission of pollutants to be (2), and then the system automatically enters the first cycle (set to 1 hour) for processing. The specific process is as follows:

[0122] 1) Reduce the frequency of the kiln dust collector fan:

[0123] FanFreq1=38*(1-η*cos(t / 2T1*π))=28.88Hz

[0124] Where FanFreq1 represents the fan frequency after the first cycle of dust removal in the kiln (1h), t is the time taken from the start of the time taken from the concentration of abnormal particulate matter: 1h, T1 is the set required treatment time of 5h, and η is 0.253.

[0125] 2) Reduce the supply of combustion air:

[0126] ComAir1=960*(1-θ*cos(t / 2T1*π))=739m 3 / h

[0127] Where ComAir1 represents the amount of combustion air after the first cycle treatment (1h), t is the time taken from the start of the treatment of abnormal particulate matter concentration: 1h, T1 is the set required treatment time of 5h; θ takes the value of 0.243;

[0128] 3) Increase gas usage:

[0129] Gas1=8500*(1+§cos(t / 2T1*π))=8763m 3 / h

[0130] Where Gas1 represents the amount of gas used after the first cycle treatment (1h), t is the time taken from the start of the treatment of abnormal particulate matter concentration: 1h, T1 is the set required treatment time of 5h; § takes the value 0.033;

[0131] 4) Adjust the drive air pressure:

[0132] DrvAir1=40*(1-δ*cos(t / 2T1*π))=29.98kpa

[0133] Among them, DrvAir iThe driving air pressure is indicated after the first cycle treatment (1 hour), t is the time taken from the start of the treatment of abnormal particulate matter concentration: 1 hour, T1 is the set required treatment time of 5 hours; δ is 0.282.

[0134] When t = 1 hour, the measured oxygen content K3 in the flue gas is 14.9%, which is calculated according to the formula.

[0135] Conversion concentration of particulate matter from lime kiln dust collectors:

[0136] T 折算 = (K1-K2) / (K1-K3)×K4

[0137] =6.95mg / m 3 >6.5mg / m 3 (Safe concentration);

[0138] in:

[0139] T 折算 Conversion concentration of particulate matter, mg / m³ 3 ;

[0140] K1: Baseline oxygen content in ambient atmosphere, 21%;

[0141] K2: The baseline oxygen content of the kiln under normal conditions, 8%;

[0142] K3: Measured oxygen content in flue gas, 14.9%;

[0143] K4: Measured atmospheric particulate matter emission concentration, 3.26 mg / m³ 3 ;

[0144] 2. Due to T 折算 If the safety standard is not met, the system determines the severity of the abnormal ultra-low emission of pollutants to be (2), and then the system automatically enters the second cycle (set to 1 hour) for processing. The specific process is as follows:

[0145] 1) Reduce the frequency of the kiln dust collector fan:

[0146] FanFreq2=28.88*(1-η*cos(t / 2T1*π))=21.66Hz

[0147] Where FanFreq2 represents the fan frequency of the kiln dust collector during the second cycle of treatment at 41 minutes, t is the time taken from the start of the time taken from the concentration of abnormal particulate matter: 0.68h, T1 is the set required treatment time of 5h, and η is 0.253.

[0148] 2) Reduce the supply of combustion air:

[0149] ComAir2=739*(1-θ*cos(t / 2T1*π))=562m 3 / h

[0150] Where ComAir2 represents the fan frequency at 41 minutes of the second cycle, t is the time taken from the start of processing the abnormal particulate matter concentration: 0.68h, T1 is the set required processing time of 5h; θ takes the value of 0.243.

[0151] 3) Increase gas usage:

[0152] Gas2=8763*(1+§cos(t / 2T1*π))=9043m 3 / h

[0153] Where Gas2 represents the fan frequency at 41 minutes of the second cycle, t is the time taken from the start of processing the abnormal particulate matter concentration: 0.68h, T1 is the set required processing time of 5h; § takes the value 0.033;

[0154] 4) Adjust the drive air pressure:

[0155] DrvAir2=29.98*(1-δ*cos(t / 2T1*π))=21.59kpa

[0156] Where DrvAir2 represents the fan frequency at 41 minutes of the second cycle, t is the time taken from the start of processing the abnormal particulate matter concentration: 0.68h, T1 is the set required processing time of 5h; δ is 0.282.

[0157] When t = 41 minutes, the measured oxygen content K3 in the flue gas is 14.47%, which can be calculated using the formula.

[0158] Conversion concentration of particulate matter from lime kiln dust collectors:

[0159] T 折算 = (K1-K2) / (K1-K3)×K4

[0160] =6.49mg / m 3 <6.5mg / m 3 (Safe concentration);

[0161] 41 minutes after the system completed its second automatic processing cycle, T 折算 It is 6.49 mg / m³ 3 Less than 6.5 mg / m³ 3 (Safe concentration), T 折算 Once the process enters a safe zone, it will automatically end, and lime kiln No. 1 will continue normal production.

[0162] Example 2

[0163] During the experimental phase, taking the dust removal process of Meigang No. 2 lime kiln (500T sleeve kiln) in April 2025 as an example, the exhaust gas emission was 58,700 m³. 3 The exhaust gas temperature was 149℃, the humidity was 7.6%, and the measured particulate matter concentration was 1.02 mg / m³. 3 The particulate matter concentration was calculated to be 1.98 mg / m³. 3 The kiln dust collector has four chambers, each with 52 filter bags. The filter bag diameter is D. 滤袋 It is 380mm.

[0164] Add pulse nozzles: Three evenly distributed nozzles are set on the top of each filter bag, with a nozzle diameter D. 喷嘴 It is 7mm, and the nozzle length is L. 喷嘴 The nozzle is 24mm in diameter and used for spraying compressed air. The nozzle angle α with the vertical direction is 15°, and the compressed air pressure P is 200Kpa. Each pulse spray consists of three nozzles sequentially circulating.

[0165] New flexible hammers: Each filter bag has a metal rod driven by a motor in the middle, with a total of 4 spherical flexible hammers installed. The included angle between the horizontal projections of the 4 flexible hammers is 90 degrees, and the spacing L between the flexible hammers is 1m. The hammers are made of high-temperature resistant flexible polyimide aerogel (PIAs). The connection between the metal rod and the hammer handle is a movable link, and the length L of the hammer handle is [not specified]. 锤柄 The diameter D of the flexible hammer is 304mm. 柔性锤 The thickness is 18mm, and the rotation speed n is 8 revolutions / s. The centripetal force of the hammer rotation raises the height of the flexible hammer, thereby striking the filter bag. At the same time, the compressed air ejected from the pulse nozzle exerts a force on the filter bag, thus effectively removing the dust accumulated in the filter bag.

[0166] The flexible hammer and nozzle work simultaneously, with a working cycle T. 工作 The duration is 40 minutes. The flexible hammer begins to rotate, and simultaneously, the three nozzles move at t... 喷嘴 = 24-second intervals for sequential cyclic blowing, pulse valve blowing duration t 持续 The time is 0.3 seconds, until the flexible hammer stops rotating. (See...) Figure 1 , Figure 2 )

[0167] It should be noted that the above embodiments are not intended to limit the scope of protection of the present invention. Equivalent transformations or substitutions made based on the above technical solutions all fall within the scope of protection of the claims of the present invention.

Claims

1. A method for controlling abnormal ultra-low emissions of pollutants from lime kilns, characterized in that, The method is divided into two cases: a method for handling abnormal ultra-low emissions of pollutants and a method for handling dust accumulation in dust collector filter bags.

2. The method for controlling abnormal ultra-low emissions of pollutants from lime kilns according to claim 1, characterized in that, Methods for handling abnormal ultra-low emissions of pollutants during normal production. The process involves periodic calculations, gradually adjusting parameters such as the frequency of the kiln dust collector fan and the supply of combustion air, with the treatment cycle ranging from 2.5 hours to 6 hours, until T... 折算 At (4.5mg / m 3 7.5 mg / m 3 When the emission level falls within the specified range, stop calculating and adjusting parameters such as the frequency of the kiln dust collector fan and the supply of combustion air (the ultra-low emission standard for particulate matter concentration is <10mg / m³). 3 (It is necessary to set the ultra-low emission concentration of pollutants to a safer range.) The calculation method is as follows: (1) When T 折算 Within the range (6.0, 8.0) and T 实测 When in the range (0, 2.9) Take the following steps: 1) Reduce the frequency of the kiln dust collector fan: FanFreq i =FanFreq i-1 *(1-η*cos(t / 2T1*π)) Equation 1 Among them, FanFreq i FanFreq represents the fan frequency of the kiln dust collector at time i. i-1 The frequency of the fan in the kiln dust removal system at time i-1 is represented, t is the time difference from the start of the timer when the concentration of abnormal particulate matter was calculated to the current time, T1 is the set processing time (2.5h, 6h), and η takes values ​​(0.211, 0.219). 2) Reduce the supply of combustion air: ComAir i =ComAir i-1 *(1-θ*cos(t / 2T1*π)) Equation 2 ComAir i ComAir represents the amount of combustion air at time i. i-1 The amount of combustion air at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was processed to the current time, T1 is the set processing time (2.5h, 6h), and θ takes values ​​(0.201, 0.209). 3) Increase gas usage: Gas i =Gas i-1 Formula 3: *(1+§cos(t / 2T1*π)) Gas i Gas represents the amount of gas used at time i. i-1 This represents the amount of gas used at time i-1, t is the time difference from the start of the timer when the concentration of particulate matter was calculated from the point of the abnormality to the current time, T1 is the set processing time (2.5h, 6h), and § takes values ​​of (0.018, 0.021). 4) Adjust the drive air pressure: DrvAir i =DrvAir i-1 Formula 4: *(1-δ*cos(t / 2T1*π)) Among them, DrvAir i DrvAir represents the driving air pressure at time i. i-1 The driving air pressure at time i-1 is represented, t is the time difference from the start of the timer from the start of the timer to the current time when the concentration of abnormal particulate matter was calculated, T1 is the set processing time (2.5h, 6h), and δ takes values ​​of (0.241, 0.249). (2) When T 折算 Within the range (6.0, 8.0) and T 实测 When in the range (3.0, 5.8) Take the following steps: 1) Reduce the frequency of the kiln dust collector fan: FanFreq i =FanFreq i-1 *(1-η*cos(t / 2T1*π)) Equation 5 Among them, FanFreq i FanFreq represents the fan frequency of the kiln dust collector at time i. i-1 The frequency of the fan in the kiln dust removal system at time i-1 is represented, t is the time difference from the start of the timer when the concentration of abnormal particulate matter was calculated to the current time, T1 is the set processing time (2.5h, 6h), and η takes values ​​(0.221, 0.229). 2) Reduce the supply of combustion air: ComAir i =ComAir i-1 *(1-θ*cos(t / 2T1*π)) Equation 6 ComAir i ComAir represents the amount of combustion air at time i. i-1 The amount of combustion air at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was processed to the current time, T1 is the set processing time (2.5h, 6h), and θ takes values ​​(0.211, 0.219). 3) Increase gas usage: Gas i =Gas i-1 Formula 7: *(1+§cos(t / 2T1*π)) Gas i Gas represents the amount of gas used at time i. i-1 This represents the amount of gas used at time i-1, t is the time difference from the start of the timer when the concentration of particulate matter was calculated from the point of the abnormality to the current time, T1 is the set processing time (2.5h, 6h), and § takes values ​​(0.021, 0.024). 4) Adjust the drive air pressure: DrvAir i =DrvAir i-1 Formula 8 (1-δ*cos(t / 2T1*π)) Among them, DrvAir i DrvAir represents the driving air pressure at time i. i-1 The driving air pressure at time i-1 is represented, t is the time difference from the start of the timer from the start of the timer to the current time when the concentration of abnormal particulate matter was processed, T1 is the set processing time (2.5h, 6h), and δ takes values ​​of (0.251, 0.259). (3) When T 折算 Within the range (6.0, 8.0) and T 实测 When in the range (5.9,10) Take the following steps: 1) Reduce the frequency of the kiln dust collector fan: FanFreq i =FanFreq i-1 *(1-η*cos(t / 2T1*π)) Equation 9 Among them, FanFreq i FanFreq represents the fan frequency of the kiln dust collector at time i. i-1 The frequency of the fan in the kiln dust removal system at time i-1 is represented, t is the time difference from the start of the timer when the concentration of abnormal particulate matter was calculated to the current time, T1 is the set processing time (2.5h, 6h), and η takes values ​​(0.231, 0.239). 2) Reduce the supply of combustion air: ComAir i =ComAir i-1 *(1-θ*cos(t / 2T1*π)) Equation 10 ComAir i ComAir represents the amount of combustion air at time i. i-1 The amount of combustion air at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was processed to the current time, T1 is the set processing time (2.5h, 6h), and θ takes values ​​(0.221, 0.229). 3) Increase gas usage: Gas i =Gas i-1 Formula Eleven: *(1+§cos(t / 2T1*π)) Gas i Gas represents the amount of gas used at time i. i-1 This represents the amount of gas used at time i-1, t is the time difference from the start of the timer when the concentration of particulate matter was calculated from the point of the abnormality to the current time, T1 is the set processing time (2.5h, 6h), and § takes values ​​of (0.025, 0.028). 4) Adjust the drive air pressure: DrvAir i =DrvAir i-1 Formula Twelve: *(1-δ*cos(t / 2T1*π)) Among them, DrvAir i DrvAir represents the driving air pressure at time i. i-1 The driving air pressure at time i-1 is represented, t is the time difference from the start of the timer from the start of the timer to the current time when the concentration of abnormal particulate matter was processed, T1 is the set processing time (2.5h, 6h), and δ takes values ​​of (0.261, 0.269). (4) When T 折算 Within the range (8.1, 10.0) and T 实测 When in the range (0, 2.9) Take the following steps: 1) Reduce the frequency of the kiln dust collector fan: FanFreq i =FanFreq i-1 Formula Thirteen: *(1-η*cos(t / 2T1*π)) Among them, FanFreq i FanFreq represents the fan frequency of the kiln dust collector at time i. i-1 The frequency of the fan in the kiln dust removal system at time i-1 is represented, t is the time difference from the start of the timer when the concentration of abnormal particulate matter was calculated to the current time, T1 is the set processing time (2.5h, 6h), and η takes values ​​(0.241, 0.249). 2) Reduce the supply of combustion air: ComAir i =ComAir i-1 Formula Fourteen: *(1-θ*cos(t / 2T1*π)) ComAir i ComAir represents the amount of combustion air at time i. i-1 The amount of combustion air at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was processed to the current time, T1 is the set processing time (2.5h, 6h), and θ takes values ​​(0.231, 0.239). 3) Increase gas usage: Gas i =Gas i-1 Formula Fifteen: *(1+§cos(t / 2T1*π)) Gas i Gas represents the amount of gas used at time i. i-1 This represents the amount of gas used at time i-1, t is the time difference from the start of the timer when the concentration of particulate matter was calculated from the point of the abnormality to the current time, T1 is the set processing time (2.5h, 6h), and § takes values ​​(0.029, 0.032). 4) Adjust the drive air pressure: DrvAir i =DrvAir i-1 Formula Sixteen: *(1-δ*cos(t / 2T1*π)) Among them, DrvAir i DrvAir represents the driving air pressure at time i. i-1 The driving air pressure at time i-1 is represented, t is the time difference from the start of the timer from the start of the timer to the current time when the concentration of abnormal particulate matter was processed, T1 is the set processing time (2.5h, 6h), and δ takes values ​​of (0.271, 0.279). (5) When T 折算 Within the range (8.1, 10.0) and T 实测 When in the range (3.0, 5.8) Take the following steps: 1) Reduce the frequency of the kiln dust collector fan: FanFreq i =FanFreq i-1 Formula 17: *(1-η*cos(t / 2T1*π)) Among them, FanFreq i FanFreq represents the fan frequency of the kiln dust collector at time i. i-1 The frequency of the fan in the kiln dust removal system at time i-1 is represented, t is the time difference from the start of the timer when the concentration of abnormal particulate matter was calculated to the current time, T1 is the set processing time (2.5h, 6h), and η takes values ​​(0.251, 0.259). 2) Reduce the supply of combustion air: ComAir i =ComAir i-1 Formula 18: *(1-θ*cos(t / 2T1*π)) ComAir i ComAir represents the amount of combustion air at time i. i-1 The amount of combustion air at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was processed to the current time, T1 is the set processing time (2.5h, 6h), and θ takes values ​​(0.241, 0.249). 3) Increase gas usage: Gas i =Gas i-1 Formula 19: *(1+§cos(t / 2T1*π)) Gas i Gas represents the amount of gas used at time i. i-1 This represents the amount of gas used at time i-1, t is the time difference from the start of the timer when the concentration of particulate matter was calculated from the point of the abnormality to the current time, T1 is the set processing time (2.5h, 6h), and § takes values ​​of (0.033, 0.036). 4) Adjust the drive air pressure: DrvAir i =DrvAir i-1 Formula 20: *(1-δ*cos(t / 2T1*π)) Among them, DrvAir i DrvAir represents the driving air pressure at time i. i-1 The driving air pressure at time i-1 is represented, t is the time difference from the start of the timer from the start of the timer to the current time when the concentration of abnormal particulate matter was processed, T1 is the set processing time (2.5h, 6h), and δ takes values ​​of (0.281, 0.289). (6) When T 折算 Within the range (8.1, 10.0) and T 实测 When in the range (5.9,10) Take the following steps: 1) Reduce the frequency of the kiln dust collector fan: FanFreq i =FanFreq i-1 Formula 21: *(1-η*cos(t / 2T1*π)) Among them, FanFreq i FanFreq represents the fan frequency of the kiln dust collector at time i. i-1 The frequency of the fan in the kiln dust removal system at time i-1 is represented, t is the time difference from the start of the timer when the concentration of abnormal particulate matter was calculated to the current time, T1 is the set processing time (2.5h, 6h), and η takes values ​​(0.261, 0.269). 2) Reduce the supply of combustion air: ComAir i =ComAir i-1 Formula 22: *(1-θ*cos(t / 2T1*π)) ComAir i ComAir represents the amount of combustion air at time i. i-1 The amount of combustion air at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was calculated to the current time, T1 is the set processing time (2.5h, 6h), and θ takes values ​​(0.251, 0.259). 3) Increase gas usage: Gas i =Gas i-1 Formula 23: *(1+§cos(t / 2T1*π)) Gas i Gas represents the amount of gas used at time i. i-1 This represents the amount of gas used at time i-1, t is the time difference from the start of the timer when the concentration of particulate matter was calculated from the point of the abnormality to the current time, T1 is the set processing time (2.5h, 6h), and § takes values ​​of (0.037, 0.042). 4) Adjust the drive air pressure: DrvAir i =DrvAir i-1 Formula 24: *(1-δ*cos(t / 2T1*π)) Among them, DrvAir i DrvAir represents the driving air pressure at time i. i-1 The driving air pressure at time i-1 is represented, t is the time difference from the start of the timer from the time the abnormal particulate matter concentration was processed to the current time, T1 is the set processing time (2.5h, 6h), and δ takes values ​​of (0.281, 0.288).

3. The method for controlling abnormal ultra-low emissions of pollutants from lime kilns according to claim 1, characterized in that, The specific methods for handling dust accumulation on dust collector filter bags are as follows: (1) Add pulse nozzles: Three evenly distributed nozzles are set on the top of each filter bag, with a nozzle diameter of D. 喷嘴 The nozzle length is L 喷嘴 It is used to spray compressed air. The nozzle makes an angle of α with the vertical direction and the compressed air pressure is P. During each pulse spray, 3 nozzles spray in sequence. (2) New Flexible Hammers: Each filter bag has a motor-driven metal rod in the middle, on which four spherical flexible hammers are installed. The included angle between the horizontal projections of the four flexible hammers is 90 degrees, and the vertical spacing between the flexible hammers is L. The hammers are made of high-temperature resistant flexible polyimide aerogel (PIAs). The connection between the metal rod and the handle of the flexible hammers is a movable link, and the length of the handle is L. 锤柄 =0.8*D 滤袋 (D 滤袋 (Filter bag diameter), the diameter of the flexible hammer is D. 柔性锤 The flexible hammer rotates at a speed of n. The centripetal force of the hammer during rotation raises the height of the flexible hammer, thereby striking the filter bag. (3) The flexible hammer and nozzle work simultaneously, with a working cycle of T. 工作 The flexible hammer begins to rotate, and simultaneously the three nozzles operate at intervals of t. 喷嘴 The pulse valve performs sequential cyclic blowing for a duration of t. 持续 until the flexible hammer stops rotating; (4) The motor drives the metal rod to rotate, which drives the flexible hammer to make a circular motion. The centripetal force of the hammer rotation raises the height of the flexible hammer, thereby striking the filter bag. At the same time, the compressed air sprayed from the pulse nozzle exerts a force on the filter bag, thereby effectively removing the dust accumulated in the filter bag.

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