A high-purity calcium oxide production equipment and a kiln body calcining kiln thereof

Abstract

The utility model provides a kind of high-purity calcium oxide production equipment and its kiln body calcining kiln.The utility model provides the kiln body calcining kiln, kiln body calcining kiln is rectangular double-chamber vertical kiln, rectangular double-chamber vertical kiln includes two kiln bodies, and hollow is set in the inside of kiln body to form kiln chamber to calcine decomposition calcium carbonate, the side wall of kiln chamber of two kiln bodies is straight-through structure, and the middle lower part of the kiln chamber of two kiln bodies is connected by connecting section, and connecting section is internally provided with air exchange passage, and the both ends of air exchange passage are respectively communicated with the middle part of the kiln chamber of two kiln bodies.The utility model provides the kiln body calcining kiln, under the premise of keeping enough high smelting temperature, can control the problems such as plugging and nodular in kiln, also improve the quality of production finished product.

Description

Technical Field

[0001] This utility model relates to the technical field of ore calcination equipment, and in particular to a high-purity calcium oxide production equipment and its kiln calcination kiln. Background Technology

[0002] Calcium oxide has wide applications in metallurgy, cement, building materials, glass, food, and pharmaceutical industries. Existing patents mainly focus on specialized equipment, production processes, and calcination techniques, concentrating on methods for preparing high-purity calcium oxide and the design of related equipment. However, related equipment for producing high-purity (95% or higher) calcium oxide faces the following challenges: Energy consumption: High-temperature calcination processes typically involve high energy consumption, potentially leading to higher production costs and environmental impact. Equipment complexity: Some equipment designs may be complex, increasing manufacturing and maintenance costs. Scalable production: Some patents may only be applicable to small-scale production; large-scale production may require further technological improvements and optimizations. Environmental impact: While some patents mention byproduct utilization, the overall description of the environmental impact and waste disposal throughout the production process is insufficient, potentially posing environmental risks. Raw material limitations: Some patents rely on specific raw materials, such as calcium sulfate, which may limit the widespread application of the technology, as raw material availability can vary by region. Cost-effectiveness: The technologies mentioned in the patents may not be economically feasible, particularly regarding raw material costs, energy consumption, and equipment investment.

[0003] Advanced double-chamber kiln calcination technology is considered a reliable solution to the aforementioned problems. The key to producing high-purity calcium oxide using a double-chamber kiln lies in increasing the calcination temperature. However, under existing large-scale production processes and equipment, excessively high calcination temperatures can lead to adhesion, kiln nodule formation, and even over-burning of calcium oxide, resulting in products that fail to meet the requirements of downstream processes. Furthermore, existing double-chamber kilns commonly employ kiln structures such as corbel kilns and suspended cylinder kilns, which contain complex annular channel structures and downward-tapering inverted conical cooling zones. These structures easily cause material accumulation and localized stagnation, or dust accumulation, which, under high-temperature calcination conditions, easily lead to adhesion, dust accumulation, and nodule formation. Therefore, it is necessary to explore the optimal "balance point" between high-temperature calcination and smooth production—that is, to maintain a sufficiently high calcination temperature while controlling kiln blockage and nodule formation as much as possible. Utility Model Content

[0004] The main purpose of this utility model is to provide a high-purity calcium oxide production equipment and its kiln for calcination, which aims to control problems such as blockage and nodule formation in the kiln while maintaining a sufficiently high calcination temperature.

[0005] To achieve the above objectives, this utility model provides a kiln for calcining high-purity calcium oxide production equipment. The kiln is a rectangular double-chamber vertical kiln, which includes two kiln bodies. The interior of each kiln body is hollow to form a kiln chamber for calcining and decomposing calcium carbonate. The side walls of the kiln chambers of the two kiln bodies have a straight-through structure. The lower part of the kiln chambers of the two kiln bodies are connected by a connecting section. An air exchange channel is provided inside the connecting section, and the two ends of the air exchange channel are respectively connected to the middle part of the kiln chambers of the two kiln bodies.

[0006] Preferably, the ventilation channel is a large-span single-arch ventilation channel, and the span length of the single-arch ventilation channel is greater than 4m.

[0007] Preferably, the cross-section of the kiln chamber, excluding the area connected to the connecting section, is a rectangular cross-section. This rectangular cross-section includes two long sides, two short sides, and four arc-shaped transition sections connecting the long sides and the short sides. The long sides include a first side and a second side with an obtuse angle.

[0008] Preferably, the included angle between the first side and the second side is 150° to 175°.

[0009] Preferably, the kiln body includes an outer kiln shell and a refractory lining located inside the kiln shell.

[0010] Preferably, the refractory lining comprises, from the outside to the inside, a calcium silicate board, a clay brick layer, a ceramic fiber blanket, and a magnesia brick layer.

[0011] Preferably, the two kiln bodies are identical in shape and size.

[0012] Preferably, the calcination zone of the kiln body is equipped with an insert-type stainless steel spray gun to spray fuel.

[0013] This utility model also proposes a high-purity calcium oxide production equipment, including the aforementioned kiln body calcining kiln, and also includes a loading device and a unloading device located at the upper and lower ends of the kiln body calcining kiln, respectively. Both the loading device and the unloading device are fully sealed systems.

[0014] Preferably, the charging equipment includes a first hopper, a second hopper located below the first hopper, a third hopper and a fourth hopper located below the second hopper. A hydraulic gate valve is installed below the first hopper, a hydraulic gate valve is installed below the second hopper, and a charging gate valve is installed in the passage between the second hopper and the third and fourth hoppers. The unloading equipment includes two ash discharge mechanisms located below the two kiln bodies, two first collection hoppers located below the two ash discharge mechanisms, a second collection hopper located below the two first collection hoppers, and a storage hopper located below the two second collection hoppers to collect their products. A discharge gate valve is provided between the first collection hopper and the second collection hopper.

[0015] The high-purity calcium oxide production equipment proposed in this utility model has the following beneficial effects: 1. The kiln chamber sidewalls of the kiln body have a straight-through structure. There are no additional supporting structures such as corbels inside. The material moves straight down from the kiln inlet to the kiln outlet. The material will not accumulate or stagnate. It has good fluidity and will not form nodules. Therefore, under the premise of maintaining a sufficiently high calcination temperature, the kiln body can control the occurrence of blockage and nodule formation problems inside the kiln. 2. The kiln chamber sidewalls of the kiln body have a straight-through structure and no irregular refractory materials inside. Therefore, there is no problem of refractory materials easily deteriorating and collapsing due to prolonged high temperature. 3. This production equipment has a simple structure, is easy to manufacture, and saves manufacturing costs; 4. The calcium oxide produced by this production equipment has both high activity and high purity. At the same time, the flue gas can be used to preheat calcium carbonate, which can meet the growing demand for environmental protection and energy conservation. It is suitable for continuous production and is a new technology equipment that is economical, energy-saving, environmentally friendly and process-controllable, meeting the needs of large-scale production of high-purity calcium oxide. 5. This production equipment is a fully sealed system from feeding into the kiln to discharging, with no dust / harmful gas leakage. It does not have the traditional air cannon and ignition structure, making it widely applicable and suitable for use in high-altitude and cold regions. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the high-purity calcium oxide production equipment of this utility model; Figure 2 This is a frontal cross-sectional view of the calcining kiln in the high-purity calcium oxide production equipment of this utility model. Figure 3 This is a side sectional view of the calcining kiln in the high-purity calcium oxide production equipment of this utility model. Figure 4 This is a schematic cross-sectional view of the kiln body calcining kiln in the high-purity calcium oxide production equipment of this utility model.

[0017] In the diagram, 1-kiln body, 2-ventilation channel, 3-kiln shell, 4-refractory lining, 5-short side, 6-first side, 7-second side, 8-arc transition section, 9-calcium silicate board, 10-lightweight refractory clay brick, 11-lightweight high-temperature resistant clay brick, 12-ceramic fiber blanket, 13-magnesia brick layer, 14-first hopper, 15-second hopper, 16-third hopper, 17-fourth hopper, 18-hydraulic slide gate valve, 19-hydraulic three-way valve, 20-loading slide gate valve, 21-ash discharge mechanism, 22-discharge gate valve, 23-insertion stainless steel spray gun, 24-dust collector, 25-flue gas reversing valve, 26-flue gas release valve, 27-combustion air release valve, 28-finished product cooling air release valve, 29-fan.

[0018] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0020] It should be noted that in the description of this utility model, the terms "lateral," "longitudinal," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] This utility model proposes a high-purity calcium oxide production equipment.

[0022] Reference Figures 1 to 4 In this preferred embodiment, a high-purity calcium oxide production device includes a kiln calcining kiln, and a charging device and a discharging device located at the upper and lower ends of the kiln calcining kiln, respectively. Both the charging device and the discharging device are fully sealed systems. The charging device is used to quantitatively transport raw material calcium carbonate into the two kiln bodies 1 of the kiln calcining kiln as needed. The discharging device is used to periodically and quantitatively discharge finished calcium oxide to a designated location. The kiln calcining kiln is a rectangular double-chamber vertical kiln, which includes two kiln bodies 1. The interior of each kiln body 1 is hollow to form a kiln chamber for calcining and decomposing calcium carbonate. The side walls of the kiln chambers of the two kiln bodies 1 have a straight-through structure. The lower part of the kiln chambers of the two kiln bodies 1 are connected by a connecting section. An air exchange channel 2 is provided inside the connecting section, and the two ends of the air exchange channel 2 are respectively connected to the middle part of the kiln chambers of the two kiln bodies 1.

[0023] Reference Figure 2 and Figure 3 The straight-through structure of the kiln chamber sidewalls of the two kiln bodies 1 means that their sidewalls are straight up and down, without any auxiliary structures such as brackets on the inner sidewalls. This embodiment uses high-grade calcium oxide as an example for specific explanation. Kiln body 1 can be divided into a preheating zone, a calcination zone, and a cooling zone according to the calcination area. The preheating zone is used to preheat the cold calcium carbonate material with high-temperature flue gas after calcination. The calcination zone is used for high-temperature decomposition of calcium carbonate, and the cooling zone is used for cooling the finished calcium oxide product. Kiln body 1 is used for high-temperature calcination and decomposition of calcium carbonate to obtain high-purity calcium oxide.

[0024] In this embodiment, refer to Figure 3The ventilation channel 2 is a single-arch ventilation channel with a span of 4.5m. By setting the ventilation channel 2 as a large single-arch channel, the airflow exchange between the two kiln bodies 1 is smooth, thereby effectively reducing ash accumulation.

[0025] Specifically, refer to Figure 4 The kiln body 1, excluding the area connected to the connecting section, has a cross-section that is roughly rectangular. This rectangular cross-section includes two long sides, two short sides 5, and four arc-shaped transition sections 8 connecting the long sides and short sides 5. The long sides include a first side 6 and a second side 7 with an obtuse angle. The first side 6 and the second side 7 form an angle of 150° to 175°.

[0026] In this embodiment, by setting the cross-section of the kiln chamber of the kiln body 1 to a rectangular cross-section, it is more conducive to the balanced distribution of airflow and material flow compared to the existing C-shaped or O-shaped cross-section. At the same time, the bricks laid in a rectangular cross-section can overcome the problems of long-side refractory material collapse and tipping caused by pure rectangular structure.

[0027] Specifically, in this embodiment, referring to Figure 2 The kiln body 1 includes an outer kiln shell 3 and an inner kiln shell 4 located inside the outer kiln shell 3. (Refer to...) Figure 4 The kiln shell 4 includes, from the outside to the inside, a calcium silicate plate 9, a clay brick layer, a ceramic fiber blanket 12, and a magnesia brick layer 13. The clay brick layer includes an inner layer of lightweight refractory clay bricks 10 and an outer layer of lightweight high-temperature resistant clay bricks 11.

[0028] In this embodiment, the two kiln bodies 1 have the same shape and size.

[0029] Furthermore, referring to Figure 1 The calcining zone of the kiln body 1 is equipped with an insert-type stainless steel spray gun 23 to spray fuel. The kiln body 1 is provided with holes for the insert-type stainless steel spray gun 23 to be inserted. The fuel for the insert-type stainless steel spray gun 23 can be gaseous, liquid or solid fuel.

[0030] Specifically, refer to Figure 1 The charging equipment includes a first hopper 14, a second hopper 15 located below the first hopper 14, a third hopper 16 located below the second hopper 15, and a fourth hopper 17. A hydraulic slide gate valve 18 is installed below the first hopper 14, and a hydraulic three-way valve 19 is installed below the second hopper 15. Charging slide gate valves 20 are installed in the channels between the second hopper 15 and the third hopper 16 and the fourth hopper 17. A furnace body connector is installed above the kiln body 1.

[0031] The working process of this charging equipment is as follows: 1. Receive the charging instruction; 2. The flap of the hydraulic three-way valve 19 moves to the designated position in the regenerator kiln chamber; 3. Open the charging slide valve 20; 4. The hydraulic slide valve 18 on the kiln top opens, and charging begins; 5. Charging is completed, and the sealing valve is closed. Wait for the next charging instruction.

[0032] Each valve is sealed to form a completely sealed charging system. Charging can also be achieved when there is a certain airflow pressure in the kiln body 1, which can effectively shorten the switching time between two continuous combustion cycles and improve charging efficiency.

[0033] Specifically, refer to Figure 1 The unloading equipment includes two ash discharge mechanisms 21 located below the two kiln bodies 1, two first collection hoppers located below the two ash discharge mechanisms 21, a second collection hopper located below the two first collection hoppers, and a storage hopper located below the two second collection hoppers to collect their products. A discharge gate valve 22 is installed between the first collection hoppers and the second collection hoppers. Both the loading and unloading equipment are remotely controlled by hydraulic automation.

[0034] The working process of this high-purity calcium oxide production equipment is as follows: The charging equipment quantitatively delivers the raw material calcium carbonate to the kiln for calcination. The kiln consists of two rectangular kiln bodies 1 connected together, with the kiln chambers connected by an air exchange channel 2. The two kiln chambers can be divided into a calcination chamber and a preheating chamber according to the calcination process. The calcination chamber is used to burn and decompose calcium carbonate to obtain the finished calcium oxide product. At this time, the flue gas enters the preheating chamber from the calcination chamber, and the hot flue gas heats the cold calcium carbonate entering the furnace before being discharged. After calcination for a certain period of time, the functions of the calcination chamber and the preheating chamber are interchanged, thus achieving continuous production through a cyclical process. The calcination belt is equipped with calcination spray guns and the required combustion air. When the kiln body 1 is under positive pressure sintering, the calcination temperature can reach 1000℃~1150℃, obtaining high-purity calcium oxide products under high-temperature calcination. Finally, the product is discharged through the unloading equipment. The storage hopper unloads the material quantitatively according to demand.

[0035] The key technical points of the high-purity calcium oxide production equipment proposed in this invention include the following: (1) Dual-chamber kiln design: The dual-chamber kiln consists of two vertically arranged kiln chambers, which are interconnected by a connecting section located in the lower part of the kiln body 1. (2) Parallel-flow calcination: In the dual-chamber calcium oxide kiln, the calcination process in which combustion products and calcium carbonate flow downwards together helps to calcine high-quality active calcium oxide. (3) Heat storage function: High-temperature flue gas is guided from the first kiln chamber to the second kiln chamber. This flue gas contains a large amount of heat energy, which is used to preheat the calcium carbonate in the second kiln chamber, thereby improving the heat utilization rate. (4) Alternating working principle: The calcination and heat storage functions of the first and second kiln chambers are interchanged to ensure continuous production. (5) Energy saving and high efficiency: Due to its advanced process design, the rectangular dual-chamber kiln produces very high-quality finished products when the physical and chemical properties of the raw materials, the calorific value of the fuel, and the composition are within the normal range, meeting the needs of rapid smelting such as steelmaking converters. (6) Applicable to multiple fuels: The rectangular double-chamber kiln can use various forms of fuel, including solid, gaseous and liquid fuels, such as coal gas, oil and pulverized coal. (7) High-activity calcium oxide production: The calcium oxide produced by the rectangular double-chamber kiln has high activity, usually ≥300ml, and residual CO2 <3.0%. (8) Low heat consumption: The unit heat consumption of the double-chamber kiln is low, only 3344~3720kJ / kg calcium oxide. (9) Wide range of raw material particle size adaptability: The rectangular double-chamber kiln can calcine particles with a size of 30~100mm, which is more important given the decreasing availability of calcium carbonate resources in China.

[0036] The high-purity calcium oxide production equipment proposed in this invention has the following beneficial effects: 1. The side wall of the kiln chamber of kiln body 1 is a straight-through structure. There are no additional supporting structures such as corbels inside. The material moves straight down from the kiln inlet to the kiln outlet. The material will not accumulate or stagnate. It has good fluidity and will not form nodules. Therefore, kiln body 1 can control the blockage and nodule formation problems in the kiln while maintaining a sufficiently high calcination temperature. 2. The kiln chamber sidewall of kiln body 1 has a straight-through structure and no heterogeneous refractory material inside. Therefore, there is no problem of refractory material easily deforming and collapsing due to prolonged high temperature. 3. This production equipment has a simple structure, is easy to manufacture, and saves manufacturing costs; 4. The calcium oxide produced by this production equipment has both high activity and high purity. At the same time, the flue gas can be used to preheat calcium carbonate, which can meet the growing demand for environmental protection and energy conservation. It is suitable for continuous production and is a new technology equipment that is economical, energy-saving, environmentally friendly and process-controllable, meeting the needs of large-scale production of high-purity calcium oxide. 5. This production equipment is a fully sealed system from feeding into the kiln to discharging, with no dust / harmful gas leakage. It does not have the traditional air cannon and ignition structure, making it widely applicable and suitable for use in high-altitude and cold regions.

[0037] This utility model also proposes a kiln for calcining high-purity calcium oxide production equipment.

[0038] In this preferred embodiment, a kiln for producing high-purity calcium oxide is provided. The kiln is a rectangular double-chamber vertical kiln, which includes two kiln bodies 1. The interior of each kiln body 1 is hollow to form a kiln chamber for calcining and decomposing calcium carbonate. The side walls of the kiln chambers of the two kiln bodies 1 are straight-through structures. The lower part of the kiln chambers of the two kiln bodies 1 are connected by a connecting section. An air exchange channel 2 is provided inside the connecting section, and the two ends of the air exchange channel 2 are respectively connected to the middle part of the kiln chambers of the two kiln bodies 1.

[0039] Ventilation channel 2 is a single-arch ventilation channel with a span of 4.5m. By setting ventilation channel 2 as a large single-arch channel, the airflow exchange between the two kiln bodies 1 is smooth, thereby effectively reducing ash accumulation.

[0040] Specifically, the kiln body 1 includes an outer kiln shell 3 and an inner kiln shell 4. The kiln shell 4 includes, from the outside to the inside, a calcium silicate plate 9, a clay brick layer, a ceramic fiber blanket 12, and a magnesia brick layer 13. The two kiln bodies 1 are identical in shape and size.

[0041] The calcination zone of kiln body 1 is equipped with an insert-type stainless steel spray gun 23 to spray fuel. The ventilation channel 2 is set as a single-arch large channel, so the airflow exchange between the two kiln bodies 1 is smooth, thereby effectively reducing ash accumulation.

[0042] Specifically, refer to Figure 4 The kiln body 1, excluding the area connected to the connecting section, has a cross-section that is roughly rectangular. This rectangular cross-section includes two long sides, two short sides 5, and four arc-shaped transition sections 8 connecting the long sides and short sides 5. The long sides include a first side 6 and a second side 7 with an obtuse angle. The first side 6 and the second side 7 form an angle of 150° to 175°.

[0043] In this embodiment, by setting the cross-section of the kiln chamber of the kiln body 1 to a rectangular cross-section, it is more conducive to the balanced distribution of airflow and material flow compared to the existing C-shaped or O-shaped cross-section. At the same time, the bricks laid in a rectangular cross-section can overcome the problems of long-side refractory material collapse and tipping caused by pure rectangular structure.

[0044] The above are merely preferred embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A calcining kiln for producing high-purity calcium oxide, characterized in that, The kiln is a rectangular double-chamber vertical kiln, which includes two kiln bodies. The interior of each kiln body is hollow to form a kiln chamber for calcining and decomposing calcium carbonate. The side walls of the kiln chambers of the two kiln bodies are straight-through structures. The lower part of the kiln chambers of the two kiln bodies are connected by a connecting section. An air exchange channel is provided inside the connecting section, and the two ends of the air exchange channel are respectively connected to the middle part of the kiln chambers of the two kiln bodies.

2. The kiln body calcining kiln of the high-purity calcium oxide production equipment as described in claim 1, characterized in that, The ventilation channel is a single-arch ventilation channel with a span length greater than 4m.

3. The kiln body calcining kiln of the high-purity calcium oxide production equipment as described in claim 1, characterized in that, The kiln body, except for the area connected to the connecting section, has a cross-section of a rectangular shape. This rectangular cross-section includes two long sides, two short sides, and four arc-shaped transition sections connecting the long sides and the short sides. The long sides include a first side and a second side with an obtuse angle.

4. The kiln body calcining kiln of the high-purity calcium oxide production equipment as described in claim 3, characterized in that, The angle between the first side and the second side is 150°~175°.

5. The kiln body calcining kiln of the high-purity calcium oxide production equipment as described in claim 1, characterized in that, The kiln body includes an outer kiln shell and a refractory lining located inside the kiln shell.

6. The kiln body calcining kiln of the high-purity calcium oxide production equipment as described in claim 5, characterized in that, The refractory lining comprises, from the outside to the inside, a calcium silicate board, a clay brick layer, a ceramic fiber blanket, and a magnesia brick layer.

7. The kiln body calcining kiln of the high-purity calcium oxide production equipment as described in claim 1, characterized in that, The two kiln bodies are identical in shape and size.

8. The kiln body calcining kiln of the high-purity calcium oxide production equipment as described in any one of claims 1 to 7, characterized in that, The calcination zone of the kiln is equipped with an insert-type stainless steel spray gun to spray fuel.

9. A high-purity calcium oxide production equipment, characterized in that, The kiln body calcining kiln as described in any one of claims 1 to 8 further includes a charging device and a discharging device located at the upper and lower ends of the kiln body calcining kiln, respectively, and both the charging device and the discharging device are fully sealed systems.

10. The high-purity calcium oxide production equipment as described in claim 9, characterized in that, The charging equipment includes a first hopper, a second hopper located below the first hopper, a third hopper located below the second hopper, and a fourth hopper. A hydraulic gate valve is installed below the first hopper, a hydraulic gate valve is installed below the second hopper, and charging gate valves are installed in the channels between the second hopper and the third and fourth hoppers. The unloading equipment includes two ash discharge mechanisms located below the two kiln bodies, two first collection hoppers located below the two ash discharge mechanisms, a second collection hopper located below the two first collection hoppers, and a storage hopper located below the two second collection hoppers to collect their products. A discharge gate valve is provided between the first collection hopper and the second collection hopper.

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