Kiln for extracting phosphorus steam from phosphate ore

Abstract

The utility model discloses a kiln for extracting phosphorus steam from phosphate ore, which comprises a kiln body, and a preheating section, a heating section and a cooling section are sequentially arranged in the kiln body along the length direction; the rails are symmetrically arranged in the kiln body and extend in the length direction of the kiln body. At least one of the preheating section and the cooling section is provided with a phosphorus discharge port, and the phosphorus discharge port is communicated with an external phosphorus steam collecting device; in the phosphorus steam preparation process, the materials are in a static state, the phosphorus steam purity in the reaction process is high, smoke and impurities do not exist, safety and environmental protection are achieved, the operation cost is low, the automation degree is high, and trolley running, temperature control and pressure control can be automatically controlled through a computer in a central control room in the whole process.

Description

Technical Field

[0001] The utility model belongs to the technical field of extracting phosphorus vapor from phosphate rock, and particularly relates to a kiln for extracting phosphorus vapor from phosphate rock. Background Art

[0002] So far, there are two main processes in the phosphoric acid production process: (1) Wet process: decomposing medium and high-grade phosphate rock with sulfuric acid to produce phosphoric acid. This method requires a large amount of high-quality phosphate rock and sulfuric acid, and at the same time produces a large amount of phosphogypsum waste residue that is difficult to utilize. The wet-process phosphoric acid has a high impurity content, a complex purification process, and a high cost. Moreover, the price of sulfur in China has been continuously at a high level, resulting in a substantial increase in the cost of wet-process phosphoric acid; (2) Thermal process: reducing phosphate rock by the electric furnace method to produce elemental yellow phosphorus, and then burning and absorbing in a combustion tower to produce phosphoric acid. This method requires a large amount of electric energy (15,000 - 16,000 kwh of electricity is consumed per ton of yellow phosphorus produced) and medium and high-grade phosphate rock lumps, and the environmental pollution is serious. This is almost the only method for producing yellow phosphorus in the world at present, but many developed countries restrict the use of the thermal process to produce yellow phosphorus.

[0003] The kiln-process phosphoric acid is the third method different from the wet process and the thermal process. Its reaction principle is similar to that of the thermal-process phosphoric acid. The mixture is subjected to a solid-phase reaction, and the reduction and oxidation processes of elemental phosphorus are placed in one device. In this way, the heat released by the combustion of elemental phosphorus and by-product carbon monoxide can be used to provide the heat required for the reduction of elemental phosphorus, greatly saving energy consumption. At the same time, medium and low-grade phosphate rock can be used, greatly broadening the grade range of direct utilization of phosphate rock.

[0004] The existing production method for extracting phosphorus vapor from phosphate rock is to use the carbon thermal reduction method in an electric furnace, and its raw materials are phosphate rock, silica, and coke. At high temperature in the electric furnace, the phosphate rock undergoes a carbon thermal reduction reaction to generate phosphorus vapor. The phosphorus vapor and the electric furnace dust are cooled to a suitable temperature together to produce yellow phosphorus, and then the yellow phosphorus product is obtained after rinsing and refining. The high-temperature furnace slag is directly discharged from the electric furnace. If other product varieties such as red phosphorus need to be produced, it needs to be converted through the yellow phosphorus product.

[0005] At present, the domestic phosphorus vapor preparation electric furnace directly introduces the generated phosphorus vapor into the subsequent cooling and spraying system. In this way, first, the dust content in the phosphorus vapor is relatively large, and a large amount of waste residue will be generated, which contains a large amount of harmful components such as fluorides, arsenides, and heavy metals, which will cause serious harm to the environment and the human body;

[0006] On the other hand, due to the limitation of the structure of the electric furnace, the temperature of the phosphorus vapor passing through the phosphorus discharge port is relatively low, and most of the phosphorus coming down through spraying is crude phosphorus. Under the current process, the subsequent refining process of the crude phosphorus is very complex and lengthy, and the refining equipment has a complex structure, occupies a large area, and has a high investment cost. Moreover, as the use time of the electric furnace increases, dust and coke (coal) powder in the electric furnace are prone to react with the phosphorus vapor after oxidation to form metaphosphoric acid, which condenses around the electrode holes, easily causing poor electrode insulation, resulting in frequent arc strikes and furnace shutdowns. The inner wall of the furnace cavity often retains a phosphorus-containing layer, leading to increased maintenance costs. Summary of the Utility Model

[0007] In order to solve the above technical problems, the present utility model adopts the following technical solutions:

[0008] A kiln for extracting phosphorus vapor from phosphate rock, comprising:

[0009] A kiln body, inside which a preheating section, a heating section, and a cooling section are sequentially arranged along the length direction;

[0010] Tracks, symmetrically arranged inside the kiln body and extending along the length direction of the kiln body;

[0011] At least one of the preheating section and the cooling section is provided with a phosphorus discharge port, and the phosphorus discharge port is communicated with an external phosphorus vapor collection device;

[0012] A temperature measuring unit, arranged on the inner wall of the kiln body and acting on the material.

[0013] Furthermore, the kiln body is provided with an air cooling pipe for guiding the hot air in the cooling section to an external drying chamber.

[0014] Furthermore, the air cooling pipe includes a first connecting pipe penetrating through the top inside the cooling section, and both ends of the first connecting pipe are respectively connected to a second connecting pipe and a third connecting pipe, and the three form a U-shaped structure.

[0015] Furthermore, a blowing device is connected to the end of the second connecting pipe, and the end of the third connecting pipe is communicated with an external drying chamber.

[0016] Furthermore, multiple groups of phosphorus discharge ports are arranged in both the preheating section and the cooling section.

[0017] Furthermore, isolation plates are installed at the top and bottom of the kiln body, and a sealing plate is installed on the outer periphery of the kiln body.

[0018] Furthermore, the tracks are installed on the isolation plates, and the tracks penetrate through the entire kiln body.

[0019] Furthermore, refractory materials are arranged in the heating section area.

[0020] Furthermore, the temperature measuring unit is arranged inside the heating section.

[0021] Furthermore, the temperature measurement unit includes a thermocouple and a pressure measurement element.

[0022] Compared with the prior art, the utility model has the following beneficial effects:

[0023] The utility model divides the kiln body into a preheating section, a heating section, and a cooling section, and controls the temperature through the temperature measurement unit. When the material reaches the reaction temperature, a large amount of high-purity phosphorus vapor is generated. The phosphorus vapor at different temperature points can be evenly discharged to the external phosphorus collection device according to needs through the phosphorus discharge ports arranged in the preheating section and the cooling section. Among them, the temperature measurement unit in the heating section has a pressure monitoring and control system, which can also better control the pressure in the furnace. Such a setting makes the recovery efficiency of phosphorus vapor in the furnace higher;

[0024] The setting of the cooling section enables the heat brought out by the material from the heating section to be effectively recovered, thereby achieving the effect of drying the material;

[0025] During the whole preparation process, the material is in a static state, the purity of phosphorus vapor in the reaction process is high, there is no smoke, dust and impurities, it is safe and environmentally friendly, and the operation cost is low;

[0026] It has a high degree of automation, and the driving of the trolley, temperature, and pressure control throughout the process can all be automatically controlled through the computer in the central control room. Description of the Drawings

[0027] Figure 1 It is a schematic diagram of the overall structure of the kiln furnace in the embodiment of the utility model;

[0028] Figure 2 It is a schematic cross-sectional view of the preheating section of the kiln furnace in the embodiment of the utility model;

[0029] Figure 3 It is a schematic cross-sectional view of the heating section of the kiln furnace in the embodiment of the utility model;

[0030] Figure 4 It is a schematic cross-sectional view of the cooling section of the kiln furnace in the embodiment of the utility model;

[0031] The reference numerals in the accompanying drawings of the specification include:

[0032] Kiln body 1, preheating section 10, heating section 11, refractory material 110, cooling section 12, track 2, phosphorus discharge port 3, temperature measurement unit 4, first connecting pipe 50, second connecting pipe 51, third connecting pipe 52, valve 53, isolation plate 60, sealing plate 61, air blowing device 7, trolley 8. Detailed Embodiments

[0033] In order to enable those skilled in the art to better understand the utility model, the technical solutions of the utility model will be further described below in conjunction with the drawings and embodiments.

[0034] Among them, the attached drawings are only for illustrative purposes, showing only schematic diagrams rather than physical drawings, and should not be construed as a limitation on this patent; in order to better illustrate the embodiments of the present utility model, some components in the attached drawings will be omitted, enlarged or reduced, which does not represent the size of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the attached drawings may be omitted. The same or similar reference numerals in the attached drawings of the embodiments of the present utility model correspond to the same or similar components; in the description of the present utility model, it should be understood that if terms such as "upper", "lower", "left", "right", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the attached drawings, it is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the attached drawings are only for illustrative purposes and should not be construed as a limitation on this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0035] As Figure 1 a Figure 4 shown, a kiln for extracting phosphorus vapor from phosphate rock according to the present utility model includes a kiln body 1, a temperature measuring unit 4, and an air cooling pipe;

[0036] Among them, the interior of the kiln body 1 is sequentially provided with a preheating section 10, a heating section 11, and a cooling section 12 along the length direction;

[0037] Tracks 2 are symmetrically arranged in the kiln body 1, and the tracks 2 extend along the length direction of the kiln body 1;

[0038] At least one of the preheating section 10 and the cooling section 12 is provided with a phosphorus discharge port 3, and the phosphorus discharge port 3 is communicated with an external phosphorus vapor collection device;

[0039] The temperature measuring unit 4 is arranged on the inner wall of the kiln body 1 and acts on the material. Specifically, the temperature measuring unit 4 is arranged on the inner wall of the heating section 11 area. The temperature measuring unit 4 includes multiple groups of thermocouples and pressure measuring elements, and the data signal is collected and output to an external control room through a sensor. The heating at this heating section 11 can adopt a microwave heating method.

[0040] The kiln body 1 is provided with an air cooling pipe for guiding the hot air in the cooling section 12 to an external drying chamber.

[0041] The utility model divides the kiln body 1 into a preheating section 10, a heating section 11 and a cooling section 12. When the material reaches the reaction temperature, a large amount of high-purity phosphorus vapor is generated. The phosphorus vapor at different temperature points can be evenly discharged to an external phosphorus collection device through the phosphorus discharge ports 3 arranged in the preheating section 10 and the cooling section 12 as required. Among them, the temperature measuring unit 4 in the heating section 11 has a pressure monitoring and control system, which can also better control the pressure in the furnace. Such a setting makes the recovery efficiency of phosphorus vapor in the furnace higher.

[0042] During the whole preparation process, the material is in a static state. The purity of phosphorus vapor in the reaction process is high, without soot and impurities, safe and environmentally friendly, and the operation cost is low.

[0043] The degree of automation is high. The driving, temperature and pressure control of the trolley 8 throughout the process can be automatically controlled by the computer in the central control room.

[0044] The above automatic control can use the existing technology and is also easy to implement, which does not belong to the protection scope of this application. Therefore, it has at least the beneficial effects brought by the technical solutions of the above embodiments, and will not be elaborated here.

[0045] Specifically, the air-cooling pipe includes a first connecting pipe 50 penetrating through the inner top of the cooling section 12. The two ends of the first connecting pipe 50 are respectively connected to a second connecting pipe 51 and a third connecting pipe 52, and the three form a U-shaped structure.

[0046] Among them, a blowing device 7 is connected to the end of the second connecting pipe 51, and the end of the third connecting pipe 52 is communicated with an external drying chamber.

[0047] Among them, a valve 53 is also arranged on the second connecting pipe 51, specifically a butterfly valve.

[0048] The setting of the cooling section 12 enables the heat brought out by the material from the heating section 11 to be effectively recovered, so as to achieve the effect of drying the material.

[0049] In this embodiment, multiple groups of phosphorus discharge ports 3 are arranged in both the preheating section 10 and the cooling section 12.

[0050] In addition, a partition plate 60 is installed at the top and bottom of the kiln body 1, and a sealing plate 61 is installed on the outer periphery of the kiln body 1. The track 2 is installed on the partition plate 60 and penetrates through the entire kiln body 1 together with the sealing plate 61.

[0051] Among them, a refractory material 110 is arranged in the heating section 11 area. The supporting special refractory material 110 not only plays a good heat preservation role, but also has good microwave penetration, enabling the material to heat up more quickly.

[0052] For the external sealing plate 61 of the heating section 11, the top and side walls are filled with refractory materials 110 for microwave use, and an external microwave device is connected above the external sealing plate 61.

[0053] When this kiln is in use, first, the trolley 8 loaded with materials is connected to the track 2 of the kiln body 1 from the external drying chamber via the turning line. The trolley 8 is sent into the interior of the kiln body 1 by a hydraulic walking beam machine. Subsequently, the air-blowing device 7 is started. The trolley 8 sequentially passes through the preheating section 10, the heating section 11, and the cooling section 12 of the kiln body 1. When the trolley 8 with materials travels to the heating section 11, the phosphorus vapor collection device is started, and the generated phosphorus vapor is collected through different phosphorus discharge ports 3 set according to product requirements.

[0054] During the reaction in the heating section 11, the temperature and pressure of the kiln body 1 are read in real time through a thermocouple and a pressure measuring element, and its temperature is controlled not to exceed 1200 °C and the pressure is slightly positive pressure through an external control room.

[0055] Subsequently, the external air-blowing device 7 is started. After the trolley 8 enters the cooling section 12, the heat taken out by the trolley 8 from the heating section 11 is transported to the drying chamber for material drying through the air-cooling pipe by the first connecting pipe 50 and the third connecting pipe 52.

[0056] The above are only the embodiments of the present utility model. Common knowledge such as the specific structures and characteristics known in the solutions is not described in detail here. Those of ordinary skill in the art know all the common general technical knowledge in the technical field to which the utility model belongs before the application date or the priority date, can know all the existing technologies in this field, and have the ability to apply the conventional experimental means before this date. Those of ordinary skill in the art can, under the inspiration given in this application, combine their own abilities to improve and implement this solution. Some typical well-known structures or well-known methods should not become an obstacle for those of ordinary skill in the art to implement this application. It should be noted that for those skilled in the art, without departing from the structure of the present utility model, several deformations and improvements can still be made, and these should also be regarded as the protection scope of the present utility model, and these will not affect the implementation effect of the present utility model and the practicality of the patent.

Claims

1. A kiln for extracting phosphorus vapor from phosphate ore, characterized in that: include: The kiln body has a preheating section, a heating section and a cooling section arranged in sequence along the length direction; Tracks are symmetrically arranged in the kiln body and extend along the length direction of the kiln body; At least one of the preheating section and the cooling section is provided with a phosphorus discharge port, and the phosphorus discharge port is connected to an external phosphorus vapor collection device; The temperature measuring unit is arranged on the inner wall of the kiln body and acts on the material.

2. A kiln for extracting phosphorus vapor from phosphate ore as claimed in claim 1, characterized in that: The kiln body is provided with an air cooling pipe for guiding the hot air in the cooling section to the external drying chamber.

3. A kiln for extracting phosphorus vapor from phosphate ore as claimed in claim 2, characterized in that: The air cooling pipe includes a first connecting pipe that runs through the top of the cooling section. Both ends of the first connecting pipe are respectively connected to the second connecting pipe and the third connecting pipe, and the three form a U-shaped structure.

4. A kiln for extracting phosphorus vapor from phosphate ore as claimed in claim 3, characterized in that: The end of the second connecting pipe is connected to a blowing device, and the end of the third connecting pipe is communicated with an external drying chamber.

5. A kiln for extracting phosphorus vapor from phosphate ore as claimed in claim 1, 2, 3 or 4, characterized in that: A plurality of groups of phosphorus discharge ports are arranged in the preheating section and the cooling section.

6. A kiln for extracting phosphorus vapor from phosphate ore as claimed in claim 1, 2, 3 or 4, characterized in that: The top and bottom of the kiln body are provided with isolation plates, and the periphery of the kiln body is provided with sealing plates.

7. A kiln for extracting phosphorus vapor from phosphate ore as claimed in claim 6, characterized in that: The rail is installed on the isolation plate, and the rail runs through the entire kiln body.

8. A kiln for extracting phosphorus vapor from phosphate ore as claimed in claim 1, 2, 3, 4 or 7, characterized in that: The heating section area is provided with refractory material.

9. A kiln for extracting phosphorus vapor from phosphate ore as claimed in claim 8, characterized in that: The temperature measuring unit is arranged in the heating section.

10. A kiln for extracting phosphorus vapor from phosphate ore as claimed in claim 9, characterized in that: The temperature measuring unit includes a thermocouple and a pressure measuring element.

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