On the Production Operations and Fire Control Techniques of Coking Ovens

Thread Content

On the production operation and temperature control techniques of coking ovens: To ensure that coking oven operations meet the requirements of stability, high productivity, high quality, low consumption, long service life, and safety, it is essential that the equipment functions properly during the coking process, as well as that the heating regime of the coking ovens is reasonable and stable. Coking production operations include four aspects: tapping operations, coke handling operations, thermal regulation, and furnace maintenance. This article introduces the firing operation and coke oven temperature adjustment. The quenching operations include coal loading, coke pushing, coke quenching, and coke screening. Blast furnace firing control includes the determination and adjustment of temperature and pressure parameters, as well as the supply and regulation of flow rates (the amount of heating gas, air, and exhaust gas). At the same time, due to the different types of heating gas used, namely coke oven gas or lean gas, the adjustment methods vary. The proper operation of the coke oven heating equipment (including gas equipment, exhaust gas equipment, and reversing equipment) is a prerequisite for ensuring that gas, air, and exhaust gases are regulated in a proper and appropriate manner. II. Charging and Operation of Coke Oven Machinery. Coke oven machinery includes coal charging cars, coke pushing cars, and coke carriages, which are known as the four main types of vehicles. A ramming coke oven includes a coal charging and coke pushing car, a smoke suppression car, a coke retaining car, and a coke quenching car. The four types of vehicles work together to carry out the coal loading and coke removal operations in the coke oven. (1) Coke oven machinery: details such as the operating procedures of the four main vehicles, equipment composition, steel frame structure, traveling mechanism, power distribution system, pneumatic system, and cab. This article focuses on the main approaches to mechanizing and automating the coke taking-out process, which include: 1. Further mechanization of the four types of vehicles, namely the point-positioning coke pushing vehicle, coke blocking vehicle, and coal loading vehicle. All 6-meter large-volume coke ovens in our country use five-burner spacing positioning cars. The 4.3-meter coke ovens designed in the past decade also all use a coke pusher with one-point positioning at an interval of five ovens. 2. Use a furnace door and furnace door frame cleaner. Currently, there are mechanical cleaning devices; the furnace doors are equipped with spring latches and edge-knocking doors to improve sealing. 3. The rising pipes and bridge pipes are operated mechanically, with the coal loading vehicle carrying out all related tasks. 4. The interlocks for coke discharge operations include electrical interlocks, gamma-ray interlocks, magnetic induction positioning carrier signal interlocks, and laser positioning, among others. Interlock devices displaying the three furnace numbers are in use across China. 5. Tail coke handling devices include inclined chute types and chain plate conveyors, etc. 6. The focusing mechanisms for the focus table include scraper type, trolley pressing type, and feeder type, among others. 7. Fully automated operation of the four major types of vehicles. The coal loading car, coking car, and coke quenching car are all fully automatic and require no human operation ； Interlocked control is applied to the coke pusher, operated by one person. The control center inputs the operation procedure, causing the three unmanned cars to move automatically to the predetermined coke outlet number of the furnace. Once it is confirmed that this number matches that reached by the manually operated coke pusher and that the system is in operational mode, the coke pushing can be carried out automatically according to the established operation procedure. 8. The use of hydraulic systems makes the operation more reliable, lightweight, compact, fast, easily adjustable, and convenient to control. 9. A variable-frequency speed control walking mechanism is adopted. (II) Coal loading and coke pushing The requirements for coal loading are to fill it completely, level it, pack it tightly, and distribute it evenly. During the coal loading process, efforts should be made to minimize smoke, flames, and coal spraying in order to reduce environmental pollution. In modern chamber-type coke ovens, the conversion of coal into coke takes place in carbonization chambers that are arranged alongside the combustion chambers in the direction of the oven banks. Different types of coke ovens have varying numbers of chambers and volumes. To ensure balanced production in the coke ovens, to maintain consistent coking times in each carbonization chamber, and to allow for timely extraction of coke from the entire oven set, it is necessary to keep the mechanical equipment in good condition at all times. Therefore, plans for coke pushing, coal charging, and maintenance should be established according to a specific sequence for pushing coke. 1. Coke pushing sequence: The order in which coal is loaded and coke is removed from each carbonization chamber of one coke oven (or a set of two ovens) is called the coke pushing sequence. Currently, the pusher sequences used are 9-2, 5-2, and 2-1. Its general formula is m-n, where m represents the number of groups into which all the carbonization chambers of one or a set of two coke ovens are divided (group number); in other words, it is the number of furnace chambers between two consecutive coke pushing operations ； n is the number of intervals between the corresponding carbonization chamber numbers of the two passes. 2. Several time concepts in coking production: Pushing time: The time when the tip of the pushing rod comes into contact with the surface of the coke cake (referring to an instant). Coal loading time: The time when the coal leveling rod is inserted into the small furnace door to start the coal leveling operation (referring to an instantaneous period of time). Coal loading time: the interval from when the coal loader opens the gate to release the coal until coke pushing begins. Coking time: The residence time of the coal in the carbonization chamber, that is, the interval from the coal loading time and splitting time to the coke pushing time. Operation time: It is divided into three types, namely the operation time for a single furnace, the operation time for the entire furnace, and the operation time for each segment during segmented maintenance. A Single furnace operation time: The time interval between pushing out coke (or loading coal) in two adjacent carbonization chambers and doing the same again; given the current level of mechanization and automation, this time ranges from 8 to 12 minutes. B Operating time per period: the time interval from the pushing of coke in the first furnace after maintenance is completed until the pushing of coke in the last furnace is finished just before the next maintenance; in other words, it is the number of furnaces whose coke is removed during the interval between two maintenance sessions, multiplied by the operating time per furnace. C Total furnace operation time: the sum of the operation times for each stage within one cycle. Carbiding chamber treatment time: The time interval from coke pushing to coal loading in the carbiding chamber (empty furnace time). The difference arising from single furnace operation time should be clearly distinguished. Turnaround time (also known as small cycle time): the time interval from coke pushing (coal charging) in a certain carbonization chamber to the next coke pushing (coal charging). 3. Cyclical maintenance and coke pushing plan: To maintain balanced production, regular maintenance is necessary, and a cyclical maintenance and coke pushing plan is usually employed to organize the coke removal operations. The cyclic maintenance and coke pushing plan is prepared on a monthly basis, specifying the operating time per day and per shift, the number of cocks to be taken out, and the maintenance time for each coke oven. In fact, when the turnaround time and 24 hours take the least common multiple, a single large-cycle plan can be arranged to allow for reuse. The large cycle refers to the interval between different dates at the same time when carbonizing chambers of the same type are operated, that is, the time interval at which the small cycle starts to repeat. The time for one large cycle (h) = number of days required for one large cycle * 24 (h) = number of small cycles included in one large cycle * cycle time (h). Therefore, the time required for one large cycle can be determined by finding the least common multiple of 24 and the cycle time. When the cycle time is not an integer, 24 hours and the cycle time can first be converted into minutes, after which the least common multiple of those minute values can be used to determine the time). (III) Coking quenching and screening: There are currently two methods for coking quenching, namely wet quenching and dry quenching; wet quenching is further divided into normal-pressure quenching and pressure quenching. In recent years, the use of segmented wet quenching has led to a significant and stable reduction in the moisture content in coke, which has a notable positive impact on the proper operation of blast furnaces and energy savings. The main improvements in wet quenching of coke in recent years have involved the design of the quenching tower: dust removal devices have been added to the upper part of the tower, and the height of the exhaust stack has been increased. Various types of towers have also been developed, with the aim of reducing air pollution and recovering coke dust. The key to the wet quenching process is to reduce and stabilize the moisture content of the coke prior to thoroughly quenching it. Coke screening is primarily carried out according to the requirements of different sectors, and is generally divided into grades of 40 millimeters, 40 millimeters to 25 millimeters, 25 millimeters to 10 millimeters, and less than 10 millimeters. Grains larger than 25 millimeters are usually referred to as metallurgical coke, which is used in blast furnaces ； Coke with a particle size range of 25 mm to 10 mm, also known as coke pellets, is mainly used as vaporization coke and coke for small blast furnaces ； Those less than 0 millimeters are called coke powder, and are typically used in sintering. III. Coke Oven Heating Schedule To ensure that the coke matures evenly in both the vertical and horizontal directions within the specified coking time, it is necessary to establish and strictly enforce a heating schedule for the coke oven. Moreover, this schedule must be adjusted promptly in response to changes in actual conditions such as the coking time, coal loading amount, coal moisture content, heating gas, and climate. The main components of the coke oven heating system include the temperature regime, the pressure regime, and the supply and control regimes for flow rates (gas, air, exhaust gases). The temperature parameters include the coke cake center temperature, straight-through temperature, cooling temperature, cross-row temperature, furnace head temperature, regenerator top temperature, small flue temperature, furnace top space temperature, and furnace wall temperature. The pressure and temperature factors include the pressure at the bottom of the carbonization chamber, the pressure in the viewing port, the suction at the top of the regenerator, the suction in the small flue, and the resistance in the regenerator. The above items are commonly referred to as nine temperatures and five pressures. (1) Determination and measurement of temperature 1. Temperature at the center of the coke cake: The average temperature of the coke at the central cross-section of the carbonization chamber in the coke oven at the end of coking. It is an indicator for determining whether the entire carbonization chamber is mature; it represents a combination of the horizontal temperature in the coke oven and the vertical heating, and it also serves as a basis for determining the standard flame temperature in the combustion chamber. The methods for measuring and calculating the core temperature of coke cakes are described in heat balance. It is generally specified that 30 minutes before coke pushing (which differs slightly from the thermal equilibrium condition), a core temperature of the coke cake between 950°C and 1050°C serves as an indicator of its maturity; in actual production, this value is often higher. Therefore, with the coal blending conditions remaining unchanged, if the center temperature of the coke cake decreases by 25°C to 30°C, the standard flame temperature needs to be reduced by about 10°C. It is stipulated that it should be measured once a year. However, this temperature needs to be measured when the coking time changes by more than 1 hour, the coal blending ratio changes, the heating gas is replaced, or it is necessary to adjust the standard flame temperature. 　　　　　　　　　 2. Cooling temperature: In order to convert the temperatures of the vertical flue measured at different times after the direction change into the temperature 20 seconds after the change (when the temperature is at its highest), so as to compare the uniformity and stability of the temperature throughout the furnace and to prevent the temperature from exceeding the limit value (i.e., 1450°C), it is necessary to determine the amount of decrease in temperature in the airflow-measuring flue during the direction change; this amount constitutes the cooling temperature. The cooling temperature must be measured under conditions of normal coke oven operation and a stable heating regime. When the coke pushing sequence is 9~2 or 2~1, 9 to 10 adjacent combustion chambers should be selected; for a 5~2 sequence, 5 to 6 adjacent combustion chambers should be chosen. It is carried out in the temperature-measuring flues on the machine side and the coke side respectively; the measurement points are located between the two inclined channel entrances and the coke oven gas burners, with 4 or 6 personnel conducting the measurements. Under normal production conditions, it is specified that testing should be conducted once every six months (spring and autumn are suitable times). The cooling temperature needs to be measured when there are significant changes such as a 1-hour change in coking time, a change in reversing time, or a switch to different heating gas and heating systems. 3. Standard temperature and straight-line temperature: The standard temperature is the control value for the average temperature of the flame channels on both the machine side and the furnace side. It is the main temperature indicator for ensuring the maturity of the coke cake within the specified coking time. The basis for determining the temperature parameter is the temperature at the center of the coke cake; that is, under the specified coking time, the standard furnace temperature is determined based on the measured temperature at the center of the coke cake. The standard temperature is related to the furnace type, coal moisture content, and type of heating gas. The straight-through temperature refers to the temperature in the heating channels on the machine side and coke side of the entire furnace; it represents the temperature of the whole furnace and is the main parameter that directly affects the maturation of coke. The measurement method is: measurements begin 5 minutes (or 10 minutes) after the switchover. The measurement order should be fixed; generally, measurements start from the end on the lens side and move towards the switch side, returning from the device side to the switch side. Measure every 4 hours, three shifts a day for a total of 6 times. The measurement speed should be consistent; it is advisable to take 10 to 11 measurements per minute. Each time, the measured values are adjusted by adding cooling temperature corrections based on the temperatures recorded at different times on each side, so that the temperatures in the heating channels on all sides are uniformly corrected to the temperature 20 seconds after the switch-over. 4. The horizontal temperature refers to the temperature of each burner channel in the same combustion chamber of the coke oven; it is a parameter used to verify the rationality of the temperature distribution along the length of the combustion chamber and to ensure uniform curing of the coke cakes. Determination method ； Since the time between adjacent burners in the same combustion chamber is short, and it is only necessary to know the relative uniformity of the temperatures across the various burners in that same combustion chamber, no correction for cooling temperature is required for the measured temperatures. To avoid the impact of temperature drop after exchange on temperature measurement, each operation is carried out in a specific sequence. In the single-numbered combustion chamber, it goes from the machine side to the furnace side; in the double-numbered combustion chamber, it goes from the furnace side to the machine side. Measurements begin 5 minutes (or 10 minutes) after the swap. 5. Temperature of the side flue channels (heater temperature): The temperature of the side flue channels refers to the temperature of the end flue channels on both sides of the coke oven’s combustion chamber. Measurement method: Measurements begin 5 minutes after the exchange. The order of each measurement should be consistent; usually, it starts with the exchange from the focal side to the machine side, then returns from the machine side, completing two such exchanges. The measured values do not need to be converted to cooling temperature values. Methods to increase heat supply to the burners: when using coke oven gas for heating, it is necessary to clear and properly seal the brick gas channels in the burner flues. When heating with coke oven gas, measures can be taken to provide additional heat to the side flues; improving the insulation of the regenerator walls and the branches of the exhaust gas ducts can enhance their airtightness, which has a significant effect on raising the temperature of the side flues. 6. Temperature at the top of the regenerator: Measuring the temperature in the space at the top of the regenerator is done to check whether its temperature is within normal limits, as well as to detect any local overheating or leaks of heat from the regenerator in a timely manner. For silicon brick regenerators, the top temperature shall not exceed 1320°C, while for clay brick regenerators, the top temperature shall not exceed 1250°C. Measurement method: The temperature measurement point for the regenerator is generally selected at the highest temperature location. When heated with coking coal, measurements of the rising gas regenerator are taken immediately after the exchange (usually 5 minutes after the exchange), as measurements must be taken at least once. After measurement, the average temperatures on the computer side and the focus side (excluding the end regenerative chambers) are calculated respectively, and the highest and lowest temperatures of the regenerative chambers are indicated. 7. Temperature of the small flue: The temperature of the small flue refers to the temperature at which the exhaust gases are discharged. Measuring this temperature is primarily to check whether the heat exchange in the regenerator is functioning properly, and to detect issues such as leaks or incomplete combustion caused by poor sealing of the furnace. Measurement method: Insert a 500°C mercury thermometer into the temperature measurement hole of the exhaust gas tray located in the upward airflow, with the insertion depth being 3/5 of the total height of the small flue. Take the readings 5 to 10 minutes before the change to downward airflow (make sure to take the readings first and then remove the thermometer), calculate the average, and identify the highest and lowest temperatures. When burning blast furnace gas, the insertion thermometer should be used during the downward airflow, and it should be measured once a month. 8. Temperature in the furnace roof space: The temperature in the furnace roof space refers to the temperature of the raw gas in the space above the carbonization chamber of the coke oven. Measurement method: When 2/3 of the coking process has occurred in the carbonization chamber, a thermocouple is used to measure the temperature at the center of the roof space at the first coal charging port on the machine side; the same method is applied to the coking side of the dual gas collection pipes. It takes 15 minutes after the thermocouple is inserted before readings can be taken. The temperature in the furnace roof area should be controlled at 800°C ± 30°C, and should not exceed 850°C. Once per quarter, and also whenever the coking time changes by 1 hour or there is a significant change in the coal blending ratio. It is usually carried out simultaneously with the measurement of the core temperature of the coke cake. 9. Wall temperature of the carbonization chamber: This temperature is generally measured simultaneously with the temperature at the center of the coke cake, thereby providing an indirect indication of the temperature distribution above and below the combustion chamber. After pushing out the coke, close the furnace doors on both sides and open the rising pipe cover. Use an infrared thermometer to measure the temperatures of the two side walls at the same height as the temperature at the center of the coke cake. During measurement, all furnace lids should be closed except for the coal-loading lid used for temperature measurement. It can also be measured using an infrared thermometer from the machine side or the furnace door on the focal side. By using this method, the limitation of previously being able to measure only a few points on the furnace wall is overcome; it becomes possible to obtain a heat distribution map of the entire furnace wall. Through computer processing, the walls of the carbonization chamber are divided into grid cells corresponding to different temperatures, allowing for the identification and determination of exact temperature values as well as the heat distribution in the vertical and horizontal directions. It is also possible to measure the temperatures along the entire surface of the carbonization chamber wall within one cycle time. (II) Determination and measurement of the pressure regime When determining the pressure regime, the following principles must be followed: 1. The pressure at the bottom of the carbonization chamber should be positive throughout the coking period ； 2. The pressure at the bottom of the carbonization chamber should, under all circumstances (normal operation, changes in coking time, cessation of heating, etc.), be higher than the pressure of the adjacent combustion system of the same type as well as the atmospheric pressure ； 3. Within the same coking time, the pressure distribution along the vertical direction of the combustion system should remain stable. (III) Carburizing chamber pressure: The carburizing chamber pressure refers to the pressure that is generated when crude gas is released from the carburizing chambers of a coke oven. The coke oven and the combustion chamber are separated by just one brick, and although ovens are becoming larger and more efficient, their wall thicknesses are decreasing. As a result, the presence of gaps and cracks in the bricks forming the walls of the carbonization chamber is inevitable; in other words, the connection between the two is never airtight. During the coking process, the amount of crude gas released is also uneven; as a result, when the pressure in the gas collection pipe is low, the pressure of the gas inside the carbonization chamber can only remain higher than that in the combustion chamber and the external atmospheric pressure during the first half of the coking cycle ； At the late stage of coking, it should be lower than the pressure in the combustion chamber and the external atmosphere. Measurement method: The pressure at the bottom of the carbonization chamber is measured in order to determine and check whether the pressure in the gas collection tube is appropriate, and whether the pressure within the carbonization chamber complies with the principles established by the pressure regime. The representative furnace number for measurement should be the carburizing chamber beneath the machine-side intake pipe. After coal is loaded, a 1.2-meter-long 12.5-mm steel pipe is inserted horizontally into the carbonization chamber through a pressure measurement hole at the bottom of the furnace door (a specially designed furnace door). During the initial coal loading phase, a U-tube manometer is used for measurement; once the pressure in the carbonization chamber drops to a certain level, an inclined micromanometer is used instead. Measure every hour until the water seal of the bridge tube is turned off before coke pushing. The specified collector pressure should be maintained during the measurement process. However, in the last few measurements, if it is found that the pressure in the carbonization chamber is below 5 Pa, the pressure in the gas collection tube should be increased appropriately. It is measured twice a year (in summer and winter). IV. Characteristics of heating with lean gas (I) Characteristics of heating with blast furnace gas 1. Blast furnace gas needs to be preheated. Blast furnace gas has a low calorific value, typically ranging from 3200 kj/m3 to 4000 kj/m3; due to this low calorific value, it does not require combustion. In order to obtain a heat effect similar to that of coke oven gas when it burns, in addition to preheating the air, blast furnace gas must also be preheated. Therefore, when heated with blast furnace gas, in the regenerator of the upward airflow in the combustion system, there is 1/2 preheated air and 1/2 preheated gas; both the gas and the air enter the combustion chamber through the inclined channels to burn. 2. High resistance in the combustion system: Due to its low calorific value, blast furnace gas requires a large amount of heat to be processed; as a result, a large volume of waste gas is generated, and this gas has a high density, which in turn leads to high resistance. When heated with blast furnace gas, less air is required, but the gas and air pass through separate regenerative chambers; whereas when heated with coke oven gas, both regenerative chambers are supplied with air. Therefore, when the upward airflow increases, the resistance to burning blast furnace gas also increases. 3. Long combustion flame: Due to the high proportion of inert components in blast furnace gas, accounting for about 70%, the combustion flame is elongated, which improves the uniformity of heating across the top and bottom of the coke cake. Therefore, at the same coking time, the standard furnace temperature is lower than that when heated with coke oven gas. The temperature at the bottom of the flue is generally also below 20°C to 30°C. Due to the large volume of gas preheated in the regenerator, the temperatures of the regenerator, the small flue ducts, the branch flue ducts, and even the exhaust gas at the base of the chimney are relatively lower. Generally, the temperature of the small flue is 40°C to 60°C lower. 4. Blast furnace gas is highly toxic. The CO content in blast furnace gas ranges from 25% to 30%, which gives it high toxicity; therefore, measures to prevent leaks are necessary. To prevent the leakage of blast furnace gas, it is first necessary to ensure that the gas-related equipment is airtight; when installing blast furnace gas systems, the pressure testing requirements must be strictly followed. In daily operation, the plug should be cleaned and lubricated regularly to ensure its tightness, and the water seal should be checked frequently to maintain a full level of water. The joints between the regenerator enclosure walls, the exhaust flange, and the small flue should be regularly sealed with mortar. Gas equipment should be regularly tested with a torch test or soapy water test to check for any gas leaks, so that they can be addressed promptly. At the same time, blast furnace gas should be under negative pressure once it enters the waste gas tray. 5. Strictly control the dust content: It is required that the dust content in blast furnace gas not exceed 0.075 g/m3. An increase in the dust content in the gas leads to an increase in the resistance in the regenerator, and cleaning measures must be taken to address this issue. (II) Adjustment of gas volume and air volume 1. Supply of coal gas: When heating with blast furnace gas, the amount of waste gas increases, and the heat carried away by this waste gas accounts for a larger proportion of the total heat consumption; as a result, the thermal efficiency on the coke side is significantly lower compared to that on the machine side. Additionally… The suction difference between the upward and downward air currents on the coke side is greater than that on the machine side, resulting in more opportunities for air leakage; therefore, the ratio of heat consumption on the coke side to that on the machine side is 1%–2% higher compared to when using coke oven gas for heating. Due to the improved uniformity of vertical heating, the standard flame temperature can be reduced by 10°C to 30°C, depending on the furnace design and coking time. A reduction in the standard flue temperature can also lead to a decrease in the amount of gas that needs to be supplied. Especially in large-volume coke ovens, when heated with blast furnace gas, the heat consumption is not necessarily much higher or it can remain the same. 2. Air supply: The density of the exhaust gas when heated with blast furnace gas is 1.37, while that when heated with coke oven gas is 1.21. Therefore, for the same coking time, the exhaust gas resistance when using blast furnace gas is approximately 2.25 times that when using coke oven gas. Therefore, the required chimney suction also increases accordingly. Based on calculations and experience, the draft required in the smoke duct when heating with blast furnace gas is 1.6 to 1.8 times greater than that when using coke oven gas, with the coking time, the opening of the chute, and the opening of the exhaust gas tray control flaps remaining unchanged. 3. Use of mixed gas: Gas has a low calorific value, which is unfavorable for heating coke ovens. The thermal efficiency of such ovens is low, energy consumption is high, and a large amount of gas is required; as a result, a large volume of waste gas is generated. This increases the resistance in the heating equipment and systems, and may even lead to insufficient capacity in the gas handling equipment and inadequate suction power in the chimneys. Therefore, in order to increase the calorific value of the gas, it is possible to mix a certain amount of coke oven gas into blast furnace gas. The control methods for heating with mixed gas and heating with blast furnace gas are basically the same. (III) Heating of the combustion chambers: Just as with heating using blast furnace gas, the amount of gas supplied to each combustion chamber is regulated by flow control orifices, while the amount of air is controlled through the inlets on the exhaust gas tray along with adjustment plates. The difference is that blast furnace gas is also preheated in regenerative chambers; therefore, just like air, the amount of gas entering each combustion chamber is controlled by the suction at the top of the regenerative chambers. 1. Control of gas and air amounts in each combustion chamber: The gas amount, air amount, and exhaust gas amount are controlled using the suction at the top of the regenerator. Control the pressure difference between the upward and downward air currents at the top of the regenerative chamber, as well as the pressure differences between the gas in the upward air current and the top of the regenerative chamber, and between the gas in the downward air current and the top of the regenerative chamber. 2. Adjustment of straight-through temperature uniformity: Since the amount of gas and air supplied to each combustion chamber is controlled by the suction at the top of the regenerator, adjusting the suction at the top of the regenerator is equivalent to adjusting the straight-through temperature uniformity. Adjusting the upward airflow suction in the gas regenerative chamber mainly involves controlling the diameter of the orifice plates in each branch pipe ； Adjusting the upward airflow suction in the air heat storage chamber mainly involves controlling the opening degree of the air inlet ； Adjusting the suction in the downward-flow regenerative chamber mainly involves controlling the opening degree of the exhaust gas tray’s regulating flap. And there are connections between them. Under normal conditions, the opening degree of the air inlets throughout the furnace is kept consistent. The upward airflow suction in each air regenerative chamber is regulated by adjusting the flaps using the adjacent downward airflow waste gas trays. V. Conclusion: Temperature adjustment is the most crucial and essential quality control point. The heating process parameters are a function of the furnace age and are variables. Controlling the variations in heating parameters involves multiple elements: gas, air, and flow direction switching time. And the control of the switching time can be achieved by adjusting the switch traffic ； Pressure or tie-rod stroke control – adjusting the temperature necessarily changes the \"coking time,\" which in turn leads to a decrease in the amount of raw gas. This causes changes in the pressure in the gas collection ducts, prompting the \"heart fan\" to adjust its rotation speed by manually modifying the opening angle of the L-shaped tubes. It also results in corresponding adjustments to the amount of recycled ammonia water used, in order to control the temperature of the gas in the gas collection ducts.