Regeneration hot blast stove

Abstract

The utility model provides a regeneration hot-blast stove. The regeneration hot-blast stove comprises a combustor; the hot air hearth is connected with the combustor and comprises a mixing cavity, a cooling air inlet for inputting circulating cooling air into the mixing cavity and a hot air outlet, and the hot air outlet is used for outputting high-temperature hot air formed by heat exchange of combustion flames and the circulating cooling air in the mixing cavity; the regeneration drying cylinder is used for containing asphalt recycled materials, and the inlet end of the regeneration drying cylinder communicates with a hot air outlet of the hot air hearth. An air inlet of the circulating fan is connected to the outlet end of the regeneration drying cylinder, and an air outlet of the circulating fan is connected to a cooling air inlet of the hot air hearth through a circulating air duct; and the electric adjusting air door is arranged in the circulating air duct, and the opening degree of the electric adjusting air door is linked with the load of the combustor, so that the temperature of the high-temperature hot air is stabilized within the target temperature interval, and the asphalt recycled materials are prevented from being aged. The structure not only reduces the cost, but also can avoid the problem of asphalt aging.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of asphalt mixture mixing equipment, in particular to a regeneration hot blast furnace. BACKGROUND

[0002] With the increasing perfection of domestic highway construction, the main work of the highway gradually changes from construction to maintenance, renovation and reconstruction. In the process of renovation and reconstruction, a large amount of asphalt concrete waste materials is generated. The recycling of asphalt concrete recycling materials can reduce resource waste and environmental pollution, and is the trend of the times. The recycling material addition ratio will also be larger and larger. In order to realize large-scale addition of asphalt concrete recycling materials, the discharge temperature of the recycled asphalt material needs to be improved. The hot blast furnace can heat the asphalt concrete recycling material by high-temperature flue gas in a countercurrent manner, so that the discharge temperature can reach the level of the original material, which is a technology to realize large-scale addition. In recent years, the demand for hot blast furnaces has been increasing.

[0003] In the prior art, some manufacturers configure and use countercurrent hot blast furnaces. The hot blast temperature is generally controlled at 800-1000℃. The high hot blast temperature causes the asphalt component in the recycled material to age seriously, and more new asphalt needs to be added to meet the technical requirements of the finished material. At the same time, the larger the proportion of recycled materials, the greater the load of the burner, and the higher the hot blast temperature, the more serious the burning loss of the asphalt component in the recycled material, and the more new asphalt needs to be added. This not only increases the cost, but also aggravates the burning loss of asphalt. CONTENT OF THE INVENTION

[0004] In view of the above defects or deficiencies in the prior art, the present application aims to provide a regeneration hot blast furnace, comprising:

[0005] a burner;

[0006] a hot blast furnace, connected with the burner, the burner being used to provide a combustion flame to the hot blast furnace; the hot blast furnace comprising a mixing chamber, a cooling air inlet for inputting circulating cooling air into the mixing chamber, and a hot blast outlet for outputting high-temperature hot blast formed by heat exchange between the combustion flame and the circulating cooling air in the mixing chamber;

[0007] a regeneration drying cylinder for containing asphalt recycling materials, the inlet end of the regeneration drying cylinder being in communication with the hot blast outlet of the hot blast furnace;

[0008] a circulating fan, the air inlet of the circulating fan being connected to the outlet end of the regeneration drying cylinder, and the air outlet of the circulating fan being connected to the cooling air inlet of the hot blast furnace through a circulating air duct;

[0009] An electrically-operated regulating air door is arranged in a circulating air duct, and the opening degree of the electrically-operated regulating air door is linked with the load of the burner to stabilize the temperature of the high-temperature hot air in a target temperature range and prevent the asphalt reclaimed material from aging.

[0010] According to the technical scheme provided in the embodiment of the present application, the air volume of the circulating air fan is 3 times the air volume of the burner fan, and the power of the circulating air fan matches the maximum load of the burner.

[0011] According to the technical scheme provided in the embodiment of the present application, the electrically-operated regulating air door is a linear regulating air door, and the opening degree change of the linear regulating air door is in a positive proportional relationship with the load of the burner.

[0012] According to the technical scheme provided in the embodiment of the present application, the outlet end of the regeneration drying cylinder is connected with the hot blast stove through a flue fan.

[0013] According to the technical scheme provided in the embodiment of the present application, the opening degree adjustment of the electrically-operated regulating air door is linked with the load of the burner through a PLC program.

[0014] According to the technical scheme provided in the embodiment of the present application, a wind pressure sensor is further arranged in the circulating air duct to monitor the circulating air volume and form a closed loop with the PLC program.

[0015] According to the technical scheme provided in the embodiment of the present application, the hot blast stove and the regeneration drying cylinder are both provided with a heat insulation layer to prevent heat loss.

[0016] According to the technical scheme provided in the embodiment of the present application, the fuel supply system of the burner is connected with the PLC program.

[0017] According to the technical scheme provided in the embodiment of the present application, the target temperature range is 450-600 DEG C.

[0018] Compared with the prior art, the present application has the beneficial effects that: the circulating cooling air is used to dilute the combustion flame temperature, the electrically-operated regulating air door is used to dynamically control the circulating air volume, the temperature of the hot air is reduced to a target range (for example, 450-600 DEG C), the aging of the asphalt is avoided, the addition amount of new asphalt is reduced, and the cost is reduced. The electrically-operated regulating air door is linked with the load of the burner, when the load increases, the opening degree of the air door is increased synchronously, the circulating cooling air volume is increased to inhibit the temperature rise, the positive correlation cycle of the load and the temperature is broken, the temperature is stabilized and controlled, and the aging of the asphalt is avoided. Based on the real-time signal of the load of the burner, the circulating air volume is automatically adjusted through the electrically-operated regulating air door, a closed loop control is formed, the temperature control precision is improved, the working condition requirements under different addition proportions of the regenerated material are met, and the manual intervention error is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1A structure schematic diagram of the regenerative hot blast stove provided by the embodiment of the present application is shown in the figure.

[0020] Figure 2 A relationship curve diagram between the opening of the electrically-regulated damper and the burner load provided by the embodiment of the present application is shown in the figure.

[0021] The text annotations in the figure represent:

[0022] 1, burner; 2, hot blast stove chamber; 3, regenerative drying cylinder; 4, flue fan; 5, circulating fan; 6, electrically-regulated damper. DETAILED DESCRIPTION

[0023] The present application will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related application, and not to limit the application. In addition, it should be noted that only the parts related to the application are shown in the drawings for ease of description.

[0024] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and embodiments.

[0025] Embodiment 1

[0026] As mentioned in the background, in view of the problems in the prior art, the present application provides a regenerative hot blast stove, as shown in the figure, comprising: Figure 1 as shown, including:

[0027] a burner 1;

[0028] a hot blast stove chamber 2 connected with the burner 1, the burner 1 being used to provide a combustion flame to the hot blast stove chamber 2; the hot blast stove chamber 2 comprising a mixing chamber, a cooling air inlet for inputting circulating cooling air into the mixing chamber, and a hot air outlet for outputting high-temperature hot air formed by heat exchange between the combustion flame and the circulating cooling air in the mixing chamber;

[0029] a regenerative drying cylinder 3 for containing asphalt recyclates, an inlet end of the regenerative drying cylinder 3 being in communication with the hot air outlet of the hot blast stove chamber 2;

[0030] a circulating fan 5, an air inlet of the circulating fan 5 being connected to an outlet end of the regenerative drying cylinder 3, and an air outlet of the circulating fan 5 being connected to the cooling air inlet of the hot blast stove chamber 2 through a circulating air duct;

[0031] An electrically-operated regulating damper 6 is arranged in the circulating air duct, the opening degree of the electrically-operated regulating damper 6 is linked with the load of the burner 1, so that the temperature of the high-temperature hot air is stabilized in the target temperature range, and the aging of the asphalt recyclate is prevented.

[0032] Specifically, the burner 1 is a device that reasonably mixes fuel and air and ignites to generate a combustion flame, which is selected according to the required heat load of the hot blast furnace and the type of fuel. The hot blast stove 2 is one of the core components of the hot blast furnace, which is used for heat exchange between the combustion flame and the circulating cooling air to generate high-temperature hot air. It is usually made of high-temperature resistant materials such as refractory bricks, etc. The mixing chamber is a space area in the hot blast stove 2, where the combustion flame exchanges heat with the circulating cooling air, and it is part of the internal structure of the hot blast stove 2, which is integrally formed during the customization and processing of the hot blast stove 2. The cooling air inlet is the passage for the circulating cooling air to enter the mixing chamber of the hot blast stove 2, and the corresponding interface is opened during the manufacture of the hot blast stove 2 according to the design requirements. The hot air outlet is the passage for the high-temperature hot air to output from the hot blast stove 2, and the outlet is also reserved during the manufacture of the hot blast stove 2 according to the design. The regeneration drying cylinder 3 is a device for containing and heating and drying the asphalt recyclate, which is generally made of metal materials. The circulating air blower 5 is a device for driving the circulating cooling air to circulate in the system, which is selected according to the required air volume and air pressure of the system. The circulating air duct is the pipeline for the circulating cooling air to flow in the system, which is generally made of metal plates and assembled by welding or flange connection, etc. The electrically-operated regulating damper 6 is a damper that can change the opening degree by electric control, which is used to regulate the flow of circulating cooling air in the circulating air duct.

[0033] Now the technical principle is described: the burner 1 provides the combustion flame to the hot blast stove 2, in the mixing chamber of the hot blast stove 2, the combustion flame exchanges heat with the circulating cooling air entering from the cooling air inlet, generating high-temperature hot air, which is output from the hot air outlet into the regeneration drying cylinder 3 to heat the asphalt recyclate. The circulating air blower 5 sends the cooling air at the outlet end of the regeneration drying cylinder 3 back to the cooling air inlet of the hot blast stove 2 through the circulating air duct, forming a circulation. The electrically-operated regulating damper 6 is arranged in the circulating air duct, and the opening degree thereof is linked with the load of the burner 1. When the load of the burner 1 changes, the electrically-operated regulating damper 6 adjusts the opening degree accordingly, changes the flow of circulating cooling air, so that the temperature of the high-temperature hot air after heat exchange in the mixing chamber is stabilized in the target temperature range. Through the linkage of the electrically-operated regulating damper 6 and the load of the burner 1, the temperature of the high-temperature hot air can be automatically stabilized, the aging of the asphalt recyclate due to too high or too low temperature is prevented, the quality of the asphalt recyclate is ensured, and the stability and reliability of the regeneration hot blast furnace for heating treatment of the asphalt recyclate are improved.

[0034] Exemplarily, it is assumed that in an asphalt mixing station, the regeneration hot blast stove is used to heat asphalt recycling material. When the burner 1 increases the fuel supply according to the production demand, the load increases, and the heat generated by combustion increases, if the circulating cooling air flow is unchanged at this time, the temperature of the high-temperature hot air generated in the mixing cavity in the hot blast stove 2 will increase. Using the scheme mentioned in the utility model, since the electric regulating damper 6 is linked with the load of the burner 1, the electric regulating damper 6 will automatically open larger, so that more circulating cooling air enters the mixing cavity and exchanges heat with the combustion flame, thereby reducing the temperature of the high-temperature hot air, so that it is stabilized in the target temperature interval, and the asphalt recycling material is prevented from aging due to overheating.

[0035] In a preferred embodiment, the air volume of the circulating fan 5 is 3 times the air volume of the burner 1 fan, and the power of the circulating fan 5 matches the maximum load of the burner 1.

[0036] Specifically, the air volume refers to the volume of gas passing through the fan per unit time. For the fan, the power indicates how fast the fan consumes electric energy. The power of the fan is generally marked on its nameplate, and can also be obtained from the product manual. For the burner 1, the power is related to the load, and the burner 1 manufacturer will usually provide power parameters under different loads. Technical principle: The air volume of the circulating fan 5 is designed to be 3 times the air volume of the burner 1 fan, in order to ensure that there is enough circulating cooling air to participate in the heat exchange process. At the same time, the power of the circulating fan 5 matches the maximum load of the burner 1, which means that when the burner 1 is running at maximum load, the circulating fan 5 can provide enough power to ensure that the flow of circulating cooling air meets the demand for stabilizing the high-temperature hot air temperature. During system operation, the burner 1 fan sends air into the burner 1 to participate in combustion, and the circulating fan 5 circulates cooling air to the hot blast stove 2, and the specific ratio of the air volume of the two and the matching of the power of the circulating fan 5 to the maximum load of the burner 1 together maintain the heat balance of the system.

[0037] The embodiment can ensure that when the burner 1 is running at different loads, especially at maximum load, the system has enough circulating cooling air to regulate the temperature of the high-temperature hot air, so that the system can be stably operated, and the reliability of the heating temperature control of the asphalt recycling material is further improved, and the aging of the asphalt recycling material due to insufficient circulating cooling air and high temperature is prevented.

[0038] For example, in a large-scale asphalt pavement recycling project, the recycling hot air furnace operates continuously, and burner 1 is frequently under high load. Since the airflow of the circulating fan 5 is three times that of the burner 1 fan, when the burner 1 increases its fuel supply and operates under high load, the circulating fan 5 can promptly deliver a large amount of circulating cooling air into the hot air furnace 2 for heat exchange with the combustion flame. Furthermore, because the power of the circulating fan 5 matches the maximum load of the burner 1, even under prolonged high-load operation, the circulating fan 5 can operate stably, ensuring the flow rate of the circulating cooling air. This effectively stabilizes the temperature of the high-temperature hot air, ensuring that the recycled asphalt is heated at a suitable temperature and preventing aging.

[0039] In a preferred embodiment, the electrically adjustable damper 6 is a linear adjustable damper, and its opening degree is directly proportional to the load of the burner 1.

[0040] Specifically, a linear regulating damper is a damper whose opening change is linearly related to the control signal. In this system, the control signal is related to the load of burner 1. The opening change of the linear regulating damper is directly proportional to the load of burner 1. For example... Figure 2 As shown, a linear relationship exists. The electrically adjustable damper 6 adjusts according to this linear relationship. When the load on burner 1 increases, the heat generated increases, requiring more circulating cooling air to regulate the temperature. At this time, due to the characteristics of the linearly adjustable damper, its opening will increase proportionally to the increase in the load on burner 1, allowing more circulating cooling air to enter the circulating air duct. This increases the amount of cooling air entering the mixing chamber of the hot air furnace 2, exchanging heat with more of the combustion flame heat and stabilizing the temperature of the high-temperature hot air. Conversely, when the load on burner 1 decreases, the opening of the linearly adjustable damper decreases proportionally. This linear adjustment relationship makes the regulation of the circulating cooling airflow more precise and stable, more effectively maintaining the high-temperature hot air temperature within the target temperature range. This further improves the accuracy of temperature control for asphalt recycled material heating, reduces the impact of temperature fluctuations on the quality of asphalt recycled material, and prevents asphalt recycled material aging.

[0041] In a preferred embodiment, the outlet end of the regeneration drying cylinder 3 is connected to the hot air furnace 2 via a flue fan 4.

[0042] Specifically, the flue fan 4 is a fan used in the flue to assist the flow of gas. Its role is to overcome the resistance of the flue, so that the gas can flow smoothly. The outlet end of the regenerative drying cylinder 3 is connected to the hot blast stove 2 through the flue fan 4. The flue fan 4 plays a role of assisting circulation in the system, which helps to more smoothly deliver the cooling air at the outlet of the regenerative drying cylinder 3 to the hot blast stove 2. On the basis of the circulating fan 5 providing the main circulating power, the flue fan 4 further enhances the flow capacity of the cooling air, especially in the case of a long flue or a large system resistance, which can ensure the circulation amount of the cooling air and maintain the stable progress of the heat exchange process of the system.

[0043] The arrangement of the flue fan 4 in the embodiment improves the circulation efficiency of the cooling air in the system, ensures that the cooling air at the outlet of the regenerative drying cylinder 3 can be timely and effectively returned to the hot blast stove 2 to participate in heat exchange, further stabilizes the heat balance of the system, and helps to maintain the high-temperature hot air temperature within the target temperature range and prevent the asphalt reclaimed material from aging due to insufficient heat exchange.

[0044] In a preferred embodiment, the opening adjustment of the electric regulating damper 6 is linked to the load of the burner 1 through a PLC program.

[0045] Specifically, the PLC program is the program of a programmable logic controller (PLC). In the present system, the PLC program is used to control the linkage of the opening of the electric regulating damper 6 and the load of the burner 1. The PLC program has pre-written control logic, which monitors the load signal of the burner 1 in real time. When the load of the burner 1 changes, the PLC program outputs a corresponding control signal to the driving device of the electric regulating damper 6 according to the pre-set logic, so that the opening of the electric regulating damper 6 is adjusted accordingly. For example, when the load of the burner 1 increases, the PLC program detects the change and outputs a control signal to increase the opening of the electric regulating damper 6, so that the opening of the electric regulating damper 6 is increased and the flow of the circulating cooling air is increased. Conversely, the same applies. In this way, the linkage control of the opening of the electric regulating damper 6 and the load of the burner 1 is realized.

[0046] The present embodiment uses the PLC program to realize linkage control, which has the advantages of high control precision, strong reliability, and flexible modification of control logic. The opening of the electric regulating damper 6 can be more accurately adjusted according to the change of the load of the burner 1, so as to more effectively stabilize the temperature of the high-temperature hot air, improve the automation and stability of the system, and better prevent the aging of the asphalt reclaimed material.

[0047] In a preferred embodiment, a wind pressure sensor is further arranged in the circulating air duct to monitor the circulating air volume and form a closed loop with the PLC program.

[0048] Specifically, the air pressure sensor is a sensor for measuring the pressure of a gas. It converts the gas pressure signal into an electrical signal output, which can be used to monitor the pressure of the circulating cooling air in the circulating air duct, and then calculate the circulating air volume. In this system, closed-loop control refers to the circulating air volume signal monitored by the air pressure sensor being fed back to the PLC program. The PLC program compares this feedback signal with the preset air volume value and adjusts the opening degree of the electrically adjustable damper 6 to form a closed-loop control.

[0049] Technical principle: The air pressure sensor is installed in the circulating air duct to monitor the pressure of the circulating cooling air in real time and convert the pressure signal into an electrical signal to transmit to the PLC program. The PLC program calculates the circulating air volume based on the signal feedback from the air pressure sensor through a certain algorithm. Then, the PLC program compares the calculated circulating air volume with the appropriate preset circulating air volume value. If the actual circulating air volume is lower than the preset circulating air volume, the PLC program will control the electrically adjustable damper 6 to increase the opening degree to increase the circulating cooling air flow; if the actual circulating air volume is higher than the preset circulating air volume, the PLC program will control the electrically adjustable damper 6 to reduce the opening degree to reduce the circulating cooling air flow. Through this closed-loop control method, the circulating air volume is always maintained within an appropriate range to stabilize the temperature of the high-temperature hot air.

[0050] This embodiment introduces an air pressure sensor and forms a closed-loop control, further improving the accuracy and stability of the circulating air volume control. It can more accurately adjust the circulating cooling air flow according to the burner 1 load and actual system demand, thereby more effectively maintaining the high-temperature hot air temperature within the target temperature range, improving the control accuracy and reliability of the system, and better protecting the asphalt recyclate from aging.

[0051] In a preferred embodiment, the hot blast stove 2 and the regeneration drying cylinder 3 are both provided with a heat insulation layer to prevent heat loss.

[0052] Specifically, the heat insulation layer is a layer of material with low thermal conductivity, used to reduce heat transfer from one object to another, reducing heat loss. Common heat insulation materials include rock wool, glass wool, polyurethane foam, etc. The appropriate heat insulation material and construction process can be selected according to the structure and size of the hot blast stove 2 and the regeneration drying cylinder 3 to make the heat insulation layer.

[0053] This embodiment provides a heat insulation layer in the hot blast stove 2 and the regeneration drying cylinder 3. Due to the low thermal conductivity of the heat insulation material, most of the heat is confined within the area of the hot blast stove 2 and the regeneration drying cylinder 3, reducing the loss to the surrounding environment, allowing more heat to be effectively used for heating the asphalt recyclate, and improving the thermal efficiency of the system.

[0054] In a preferred embodiment, the fuel supply system of the burner 1 is connected to the PLC program.

[0055] Specifically, the fuel supply system is a system composed of equipment and pipelines that provide fuel for the burner 1. Depending on the type of fuel used by the burner 1 (such as natural gas, diesel, etc.), the composition of the fuel supply system is different. The fuel supply system of the burner 1 is connected with the PLC program, which monitors the operating state and load demand of the burner 1 in real time. When the burner 1 needs to adjust the load, the PLC program controls the operating parameters of the relevant equipment in the fuel supply system according to the preset logic, such as controlling the opening of the natural gas pressure regulating valve to adjust the natural gas flow, or controlling the speed of the diesel oil pump to adjust the diesel supply, etc. In this way, the fuel supply is matched with the load demand of the burner 1, ensuring the stable progress of the combustion process, and further affecting the generation and temperature control of the high-temperature hot air.

[0056] The present embodiment connects the fuel supply system with the PLC program, realizing accurate control of the fuel supply of the burner 1. According to the demand of the system for the temperature of the high-temperature hot air, the load of the burner 1 can be adjusted in time, making the heat output of the whole system more stable and accurate, which helps to maintain the high-temperature hot air temperature within the target temperature range, prevents the aging of the asphalt recyclate due to unstable combustion, and improves the energy utilization efficiency of the system.

[0057] The principles and implementations of the present application are described in this paper by applying specific examples. The above examples are only used to help understand the method and its core idea. The above description is only the preferred embodiment of the present application. It should be noted that due to the limitation of language expression, there are infinite specific structures, and for ordinary technical personnel in this technical field, without departing from the principles of the present application, some improvements, refinements or changes can be made, or the above technical features can be combined in an appropriate way; these improvements, refinements, changes or combinations, or the application of the inventive concept and technical solution to other occasions without improvement, shall be regarded as the protection scope of the present application.

Claims

1. A regenerative hot blast stove, characterized in that The application relates to a hot air furnace for recycling asphalt, which comprises the following components: a burner (1); a hot air furnace chamber (2) connected with the burner (1), wherein the burner (1) is used for providing a combustion flame to the hot air furnace chamber (2); the hot air furnace chamber (2) comprises a mixing cavity, a cooling air inlet for inputting circulating cooling air into the mixing cavity, and a hot air outlet for outputting high-temperature hot air formed by heat exchange between the combustion flame and the circulating cooling air in the mixing cavity; a regeneration drying cylinder (3) used for containing asphalt recycling materials, wherein an inlet end of the regeneration drying cylinder (3) is communicated with the hot air outlet of the hot air furnace chamber (2); a circulating air fan (5) with an air inlet connected to an outlet end of the regeneration drying cylinder (3) and an air outlet connected to the cooling air inlet of the hot air furnace chamber (2) through a circulating air duct; an electric regulating damper (6) arranged in the circulating air duct, wherein the opening degree of the electric regulating damper (6) is linked with the load of the burner (1) so as to stabilize the temperature of the high-temperature hot air in a target temperature range and prevent the asphalt recycling materials from aging.

2. The regenerative hot blast stove according to claim 1, characterized in that: The air volume of the circulating air fan (5) is 3 times of the air volume of the burner (1) fan, and the power of the circulating air fan (5) is matched with the maximum load of the burner (1).

3. The regenerative hot blast stove according to claim 1, characterized in that: The electric regulating damper (6) is a linear regulating damper, and the opening degree change of the electric regulating damper (6) is in a positive proportional relationship with the load of the burner (1).

4. The regenerative hot blast stove according to claim 1, characterized in that: The outlet end of the regeneration drying cylinder (3) is connected with the hot air furnace chamber (2) through a flue fan (4).

5. The regenerative hot blast stove according to claim 1, characterized in that: The opening degree adjustment of the electric regulating damper (6) is linked with the load of the burner (1) through a PLC program.

6. The regenerative hot blast stove according to claim 5, characterized in that: An air pressure sensor is arranged in the circulating air duct, which is used for monitoring the circulating air volume and forms a closed loop with the PLC program.

7. The regenerative hot blast stove according to claim 1, characterized in that: The hot air furnace chamber (2) and the regeneration drying cylinder (3) are both provided with heat insulation layers to prevent heat loss.

8. The regenerative hot blast stove according to claim 5, characterized in that: The fuel supply system of the burner (1) is connected with the PLC program.

9. The regenerative hot blast stove according to claim 1, characterized in that: The target temperature range is 450-600 DEG C.

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