Uniform air supply device for double-chamber kiln

Abstract

The utility model discloses a uniform air supply device for a double-chamber kiln, and belongs to the technical field of lime kilns. The device comprises a combustion-supporting air ring pipe arranged in a preheating zone area at the top of each kiln cylinder, the combustion-supporting air ring pipe is connected with a combustion-supporting fan, more than two combustion-supporting air branch pipelines are uniformly distributed on the combustion-supporting air ring pipe, and the combustion-supporting air ring pipe is connected with the kiln cylinder through the combustion-supporting air branch pipelines. According to the utility model, the combustion-supporting air ring pipe which is well designed is arranged in the preheating zone at the top of each kiln cylinder, and the combustion-supporting air branch pipelines which are uniformly distributed are matched, so that the precise and uniform distribution of combustion-supporting air in the kiln cylinder is effectively realized; therefore, the problem of uneven combustion caused by local too strong or too weak combustion-supporting air in the traditional design is avoided, the overall combustion efficiency is remarkably improved, and energy consumption loss and pollutant emission caused by insufficient combustion are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of lime kilns, in particular to a blast air supply device for a double-chamber kiln. Background Art

[0002] A double-chamber shaft kiln has two cylinders, which are connected by a connecting channel located in the middle of the two chambers. The advantages of the double-chamber kiln are co-current flow and heat storage. "Co-current flow" means that when the gas is burned in the combustion cylinder, the gas, the combustion-supporting air and the limestone move downward in parallel, and the combustion flue gas also moves downward, which is beneficial to calcining high-quality active lime. "Heat storage" means that in the combustion cylinder, the combustion product of the fuel - the high-temperature flue gas, enters the heat storage chamber through the connecting channel between the two kiln cylinders. In the heat storage chamber, the high-temperature flue gas flows upward from bottom to top, conveys heat to the limestone raw materials in the preheating zone, and preheats the stone materials to a relatively high temperature. At the same time, after heat exchange, the temperature of the high-temperature waste gas itself drops to a lower level, and it is discharged into the atmosphere through the flue gas bag filter.

[0003] During the combustion operation process, the two kiln cylinders of the double-chamber kiln enter the "commutation period" every 12 - 14 minutes. Through the valve action, the function conversion between the combustion kiln cylinder and the heat storage kiln cylinder is realized, that is, when one kiln cylinder is in the calcination state, the other kiln cylinder is in the heat storage state. Under normal conditions, the system conveys a large amount of gas and combustion-supporting air to the combustion chamber to ensure normal combustion in the combustion chamber, and the flue gas dust collector ensures a negative pressure environment at the top of the heat storage chamber. Therefore, the pressure in the combustion chamber is always higher than the pressure in the heat storage chamber, so that the high-temperature flue gas can flow smoothly into the heat storage chamber to realize heat storage.

[0004] The inner diameters of the preheating zone and the calcination zone of the kiln cylinder of the double-chamber kiln are 4.3 meters. In terms of the kiln type, due to the fact that the interface between the combustion-supporting air blower air duct and the kiln cylinder furnace shell is accessed unidirectionally in the design, it is easy to cause the segregation of the combustion-supporting air, that is, in the entire circular cross-section, the distribution of the combustion-supporting air is not uniform enough. Near the interface part, there is more air, and far from the interface part, there is less air. With the advancement of the large-scale kiln furnace, the circular cross-sectional area is larger. In order to reduce the air volume segregation, it is necessary to consider in the design to ensure as much as possible the uniform supply of the combustion-supporting air duct, so that the combustion is uniform. Summary of the Invention

[0005] The utility model provides a uniform air supply device for a double-chamber kiln. The air supply device can fully realize the uniform distribution of the combustion-supporting air in the kiln cylinder, make the combustion uniform, and thus solve the problem that the distribution of the combustion-supporting air in the existing double-chamber kiln is not uniform enough.

[0006] In order to solve the above problems, the technical solution adopted by the utility model is:

[0007] It includes a combustion-supporting air manifold installed in the preheating zone at the top of each kiln cylinder. The combustion-supporting air manifold is connected to a combustion-supporting air blower. Two or more combustion-supporting air branch pipes are evenly distributed on the combustion-supporting air manifold, and the combustion-supporting air manifold is connected to the kiln cylinder through the combustion-supporting air branch pipes.

[0008] In the above technical solution, a more specific technical solution may further be: a valve is provided on the combustion air branch pipe.

[0009] Further, there are 4 combustion air branch pipes, which are evenly distributed on the combustion air ring pipe.

[0010] Further, the pipe diameters of each combustion air branch pipe are the same.

[0011] Further, the valve is an electric butterfly valve.

[0012] Further, the models and specifications of each valve are the same.

[0013] Due to the adoption of the above technical solution, the utility model has the following beneficial effects compared with the prior art:

[0014] 1. Significantly improve combustion efficiency and uniformity: The utility model effectively realizes the precise and uniform distribution of combustion air in the kiln cylinder by installing a carefully designed combustion air ring pipe in the preheating zone at the top of each kiln cylinder and matching it with evenly distributed combustion air branch pipes; this not only avoids the problem of uneven combustion caused by locally too strong or too weak combustion air in the traditional design, but also significantly improves the overall combustion efficiency, reduces the energy consumption loss and pollutant emissions caused by incomplete combustion.

[0015] 2. Optimize the temperature distribution in the kiln: The uniform air supply of the utility model ensures the balance and stability of the temperature field in the kiln, reduces the uneven thermal stress and material burning loss differences caused by too large temperature gradient, thereby improving the consistency and stability of product quality; at the same time, the stable temperature environment is conducive to extending the service life of the kiln body and reducing the maintenance cost.

[0016] 3. Remarkable energy-saving and emission-reduction effects: Due to the improvement of combustion efficiency and temperature control, the utility model reduces energy consumption while also reducing the emissions of harmful gases such as nitrogen oxides (NOx), carbon monoxide (CO), etc. generated by incomplete combustion, meeting the requirements of modern industry for green and environmental protection production; in addition, the uniform combustion process helps to reduce the generation of dust and particulate matter and improve the production environment.

[0017] 4. Improve production stability and safety: The utility model optimizes the distribution of combustion air, effectively reduces potential safety hazards such as local overheating, coking or flameout caused by uneven air volume, and improves the stability and safety of the production process; at the same time, it reduces the downtime caused by frequent adjustment and maintenance, ensuring the continuity and high efficiency of production.

[0018] 5. Enhance system flexibility and controllability: By introducing electric valves into the combustion air system, the present utility model enables operators to adjust the air supply volume of each branch pipe in real time according to production requirements, enhancing the system's flexibility and response speed. This intelligent air volume control ability helps to quickly adapt to the needs of different raw material characteristics, output changes, or process adjustments, improving the overall operation efficiency and adaptability of the production line. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic process flow diagram of a double-chamber kiln.

[0020] Figure 2 It is a schematic diagram of the combustion air conveying process of a prior art double-chamber kiln.

[0021] Figure 3 It is a schematic structural diagram of the present utility model.

[0022] Figure 4 It is a cross-sectional view of a vertical cut of one of the kiln chambers of the present utility model.

[0023] Among them, Figures 1 - 4 the reference numerals in represent: 1 - combustion air blower, 2 - intermediate channel, 3 - first chamber, 4 - combustion air release valve, 5 - cooling air blower, 6 - cooling air release valve, 7 - hanging cylinder air duct, 8 - second chamber, 9 - hanging cylinder blower system, 10 - combustion air ring pipe, 11 - valve (or electric butterfly valve), 12 - hydraulic gate one, 13 - hydraulic gate two, 14 - kiln shell, 15 - combustion air branch pipe. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The present utility model will be further described in detail below with reference to the accompanying drawings:

[0025] As Figure 1 shown in the double-chamber kiln uniform air supply device, it includes a combustion air ring pipe 10 installed in the preheating zone at the top of each kiln cylinder (such as the first chamber 3 and the second chamber 8, and the same applies to the kiln cylinders mentioned below). The combustion air ring pipe 10 is connected to the air duct led out by the combustion air blower 1. Two or more combustion air branch pipes 15 are evenly distributed on the combustion air ring pipe 10, and the combustion air ring pipe 10 is connected to the kiln cylinder inside the kiln shell 14 through the combustion air branch pipe 15. That is, by installing a carefully designed combustion air ring pipe 10 in the preheating zone at the top of each kiln cylinder and matching it with evenly distributed combustion air branch pipes 15, the accurate and uniform distribution of combustion air in the kiln cylinder is effectively realized; this not only avoids the problem of uneven combustion caused by too strong or too weak local combustion air in the traditional design, but also significantly improves the overall combustion efficiency, reducing the energy consumption loss and pollutant emissions caused by incomplete combustion.

[0026] Preferably, a valve 11 is provided on the combustion air branch pipe 15.

[0027] Preferably, there are 4 combustion-supporting air branch pipes 15, which are evenly distributed on the combustion-supporting air ring pipe 10; with such a setting, its technical effects are mainly reflected in the following aspects:

[0028] ① Further improve the combustion uniformity

[0029] Evenly distribute the combustion-supporting air: The even distribution of the 4 combustion-supporting air branch pipes 15 enables the combustion-supporting air to enter the kiln barrel more evenly, avoiding the problems of excessive or insufficient local air volume, thus ensuring the uniform progress of the combustion reaction;

[0030] Reduce the temperature gradient: The even distribution of the combustion-supporting air helps to reduce the temperature gradient in the kiln barrel, making the temperature in the kiln more stable and conducive to the improvement of product quality;

[0031] ② Improve the combustion efficiency and output

[0032] Promote complete combustion: The even distribution of the combustion-supporting air can ensure the full mixing of fuel and combustion-supporting air, improve the combustion efficiency, and reduce the losses caused by incomplete combustion;

[0033] Increase the output: On the basis of the improved combustion efficiency, the production capacity of the kiln will also increase accordingly, which helps to improve the production efficiency and economic benefits of the enterprise;

[0034] ③ Enhance the system stability and controllability

[0035] System stability: The even distribution of the combustion-supporting air reduces the pressure fluctuations of the kiln barrel caused by uneven air volume, which helps to improve the stability of the entire kiln furnace system;

[0036] Flexible regulation: Cooperating with regulating devices such as valves, operators can flexibly adjust the air supply volume of each branch pipe according to production requirements, enhancing the controllability of the system;

[0037] ④ Energy conservation and emission reduction

[0038] Reduce energy consumption: Due to the improvement of combustion efficiency and the stability of temperature control, the energy consumption of the kiln furnace will be reduced accordingly, which helps to reduce the operating costs of the enterprise;

[0039] Reduce emissions: The emissions of harmful gases generated by incomplete combustion will also be reduced accordingly, meeting the environmental protection requirements and contributing to the sustainable development of the enterprise;

[0040] In summary, the improvement of "there are 4 combustion-supporting air branch pipes and they are evenly distributed on the combustion-supporting air ring pipe" not only improves the combustion uniformity and combustion efficiency, but also enhances the system stability and controllability, and at the same time achieves the effect of energy conservation and emission reduction; the realization of these technical effects is of great significance for improving product quality, increasing output, reducing energy consumption and reducing emissions, etc.

[0041] Preferably, the diameters of each combustion-supporting air branch pipe 15 are the same. With this setting, this design detail brings the following technical effects:

[0042] ① Uniform flow distribution

[0043] Precise control: Since the diameters of each combustion-supporting air branch pipe 15 are the same, when the combustion-supporting air enters each combustion-supporting air branch pipe 15 through the combustion-supporting air header pipe 10, it can ensure that the air volume in each combustion-supporting air branch pipe 15 is roughly equal, thus realizing the uniform distribution of the combustion-supporting air in the kiln barrel;

[0044] Reduction of deviation: It avoids the air volume deviation caused by different pipe diameters, and reduces the problem of affecting the combustion uniformity due to excessive or too small local air volume;

[0045] ② Improvement of system stability

[0046] Simplified management: The same pipe diameter makes the system more convenient during commissioning and maintenance, and the operator does not need to perform complex flow calibration for different pipe diameters;

[0047] Reduction of failure rate: The same pipe diameter reduces the hydrodynamic problems caused by pipe size differences, such as eddy currents and turbulence, thus reducing the risk of pipe wear and blockage, and improving the stability and reliability of the system;

[0048] ③ Energy conservation and emission reduction

[0049] Optimized combustion: The uniform flow distribution helps to achieve a more efficient combustion process, reducing the energy consumption loss and pollutant emissions caused by incomplete combustion;

[0050] Reduction of energy consumption: On the basis of the improved combustion efficiency, the energy consumption of the kiln will be correspondingly reduced, which helps to achieve the enterprise's energy conservation and emission reduction goals;

[0051] ④ Improvement of product quality

[0052] Reduction of burning loss difference: The uniform distribution of the combustion-supporting air makes the temperature field in the kiln barrel more stable, reducing the burning loss difference of materials caused by too large temperature gradient, thus improving the consistency and stability of product quality;

[0053] Increase of finished product rate: The stable combustion environment and temperature control help to reduce the defective product rate during the production process, improving the finished product rate and market competitiveness of the product;

[0054] In summary, the design with the same diameter for each combustion-supporting air branch pipe 15 not only simplifies the complexity of system commissioning and maintenance, improves the stability and reliability of the system, but also realizes the effects of energy conservation and emission reduction and improvement of product quality through optimizing the combustion process; the realization of these technical effects is of great significance for improving the production efficiency and economic benefits of the enterprise.

[0055] The valve 11 is an electric butterfly valve. With this arrangement, in the present utility model, by introducing an electric valve into the combustion air system, the operator can adjust the air supply volume of each branch pipeline in real time according to production requirements, enhancing the flexibility and response speed of the system. This intelligent air volume control ability helps to quickly adapt to the requirements of different raw material characteristics, output changes or process adjustments, and improves the overall operating efficiency and adaptability of the production line.

[0056] The models and specifications of each valve 11 are the same.

[0057] Among them, when one of the kiln chambers is under calcination, for example, when the first chamber 3 is under calcination, the combustion air blower 1 starts, the hydraulic gate 12 opens, and the electric butterfly valve 11 opens. The combustion air passes through the combustion air ring pipe 10 installed in the preheating zone at the top of each kiln barrel, and through the electric butterfly valves 11 and the combustion air branch pipelines 15 evenly distributed on the combustion air ring pipe 10, and is sent into the kiln barrel of the first chamber 3 to achieve uniform distribution of the combustion air volume.

[0058] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model, rather than to limit it; although the present utility model has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present utility model.

Claims

1. A double-chamber kiln uniform air supply device, characterized in that: It includes a combustion-supporting air ring tube installed in the preheating zone at the top of each kiln tube, the combustion-supporting air ring tube is connected to the combustion-supporting air fan, more than two combustion-supporting air branch pipes are evenly distributed on the combustion-supporting air ring tube, and the combustion-supporting air ring tube is connected to the kiln tube through the combustion-supporting air branch pipes.

2. The double-chamber kiln uniform air supply device according to claim 1, characterized in that: The combustion-supporting air branch pipeline is provided with a valve.

3. The uniform air supply device for a double-chamber kiln according to claim 2 is characterized in that: There are four combustion-supporting air branch pipes, which are evenly distributed on the combustion-supporting air ring pipe.

4. The uniform air supply device for a double-chamber kiln according to claim 3 is characterized in that: The diameter of each combustion-supporting air branch pipeline is consistent.

5. The uniform air supply device for a double-chamber kiln according to claim 4 is characterized in that: The valve is an electric butterfly valve.

6. The uniform air supply device for a double-chamber kiln according to claim 5, characterized in that: The model and specifications of each of the valves are consistent.

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