Continuous calcium carbide liquid discharging and high-temperature granulating device for closed calcium carbide furnace

Abstract

The invention discloses a closed calcium carbide furnace calcium carbide liquid continuous discharging and high-temperature granulating device which comprises a continuous discharging unit, a granulating unit and a collecting tank which are sequentially arranged from top to bottom, the continuous discharging unit comprises a closed liquid storage bin and a siphon elbow, one end of the siphon elbow is communicated with the bottom of the liquid storage bin, and the other end of the siphon elbow is communicated with the collecting tank. The other end of the siphon elbow is a first discharge hole; the granulation unit comprises a barrel and a calcium carbide sieve, the bottom surface of the barrel is open, the top of the barrel is communicated with a first discharge port, the height of the first discharge port is adjustable, and the siphon elbow discharges calcium carbide liquid in the liquid storage bin from the first discharge port by utilizing a siphon effect; the calcium carbide sieve divides the cylinder body into two areas, namely a liquid containing area and a forming area; the calcium carbide screen is used for enabling calcium carbide liquid to fall into the forming area in a liquid drop mode, and the calcium carbide liquid is cooled into calcium carbide particles in the forming area and enters the collecting tank. The discharging speed is gradually reduced through natural reduction of the liquid level difference, and the problems of high-temperature abrasion, insufficient regulation and control precision and the like of an active flow control device are expected to be avoided.

Description

Closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid Technical Field

[0001] This invention belongs to the field of calcium carbide technology, specifically relating to a closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid. Background Technology

[0002] Calcium carbide (commonly known as calcium carbide) is an important basic chemical raw material, mainly used in the production of acetylene and various acetylene-based chemical products, occupying a key position in the coal chemical industry chain. In existing electrothermal closed calcium carbide furnace production processes, the feeding method primarily involves intermittent feeding from three discharge ports. The core process is as follows: High-temperature calcium carbide liquid at 2000-2200℃ inside the furnace is fed into a cast steel calcium carbide pot through the discharge ports approximately every hour. It is then cooled in stages under natural conditions to below 100℃ to form ton-sized calcium carbide blocks, which are then crushed and screened to obtain calcium carbide particles that meet the requirements. The intermittent feeding method is mainly to adapt to the dynamic balance requirements of the strongly endothermic high-temperature melting reaction inside the furnace, avoiding large fluctuations in the liquid level that could disrupt the material layer structure and temperature field stability, while also matching the traditional calcium carbide pot transfer and natural cooling processes.

[0003] As the industry continues to raise its requirements for production efficiency, energy consumption control, and environmental protection, the limitations of traditional intermittent feeding and subsequent forming processes are becoming increasingly apparent: First, the reaction stability inside the furnace is poor, and the liquid level fluctuations caused by intermittent feeding increase the risk of crusting and material spraying, affecting the yield and quality of calcium carbide, and the overall energy consumption per ton of calcium carbide is relatively high; Second, production efficiency is limited, with a natural cooling cycle of 24-36 hours, and the subsequent crushing process is not only time-consuming but also generates a large amount of dust, polluting the environment and wasting resources; Third, equipment operation and maintenance costs are high, with frequent opening of the discharge port causing the seals to age and fail easily, and the periodic scouring of high-temperature calcium carbide liquid exacerbating the wear of the refractory materials at the discharge port, resulting in a short replacement cycle for key components; Fourth, safety risks are prominent, with frequent opening and closing of the furnace opening increasing the probability of carbon monoxide toxic gas leakage, and the characteristic of crushing dust and calcium carbide reacting with water to produce acetylene further increasing the difficulty of safety management.

[0004] To address these issues, the industry has gradually explored continuous feeding processes and direct granulation technology. Continuous feeding aims to improve reaction efficiency by stabilizing the liquid level inside the furnace, while direct granulation achieves one-time molding of calcium carbide liquid through "high-temperature granulation + rapid cooling," shortening the cooling cycle to 10-30 minutes and significantly reducing energy consumption and dust pollution. However, existing continuous feeding technologies still face core technological bottlenecks:

[0005] On the one hand, high-temperature calcium carbide liquid has high viscosity and is temperature sensitive. When using active flow control devices such as mechanical valves, the components are prone to wear and jamming at high temperatures, which leads to uncontrolled flow rate of high-temperature calcium carbide liquid, resulting in "flow interruption" or "material gushing". At the same time, continuous flushing aggravates high-temperature corrosion and wear of the equipment, and the component replacement cycle is shortened to 10-15 days.

[0006] On the other hand, existing continuous discharge technology relies on active flow control devices such as mechanical valves. Due to the lag in the adjustment of the opening of mechanical valves, it is impossible to achieve a smooth and gradual change in the flow rate of calcium carbide liquid. In scenarios where calcium carbide liquid replenishment is not timely, adjustments can only be made by "suddenly reducing the flow rate" or "emergency stopping the material". This operation will cause the calcium carbide liquid level in the furnace to drop rapidly, destroying the stability of the material layer structure, thereby increasing the risk of crusting and material spraying in the furnace, directly affecting the calcium carbide yield and the quality of gas generation. Summary of the Invention

[0007] In view of the shortcomings of the prior art, the purpose of this invention is to provide a closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid.

[0008] The objective of this invention is achieved through the following technical solution.

[0009] A closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid includes: a continuous discharge unit, a granulation unit and a collection tank arranged from top to bottom. The continuous discharge unit includes: a closed storage tank and a siphon bend. The storage tank is used to store calcium carbide liquid. One end of the siphon bend is connected to the bottom of the storage tank, and the other end of the siphon bend is the first discharge port.

[0010] The granulation unit includes a cylinder and a calcium carbide screen. The bottom of the cylinder is open, and the top of the cylinder is connected to the first discharge port. The height of the first discharge port is adjustable. The siphon bend uses the siphon effect to discharge the calcium carbide liquid in the storage tank from the first discharge port.

[0011] A horizontally arranged calcium carbide screen is installed inside the cylinder, dividing the cylinder into two zones: the cylinder above the calcium carbide screen is the liquid holding zone, and the cylinder below the calcium carbide screen is the forming zone. The calcium carbide screen is used to cause the calcium carbide liquid passing through the screen to fall into the forming zone in the form of droplets. A cold gas inlet is formed at the lower part of the cylinder in the forming zone, which is used to introduce cooling gas into the forming zone, so that the calcium carbide liquid falling into the forming zone is cooled into calcium carbide particles. A hot gas outlet is also formed at the upper part of the cylinder in the forming zone.

[0012] The opening at the bottom of the cylinder is connected to the collection tank, and the calcium carbide particles enter the collection tank.

[0013] In the above technical solution, the siphon bend includes: a first section pipe, a second section pipe, a third section pipe, a fourth section pipe and a fifth section pipe connected in sequence. The first section pipe, the third section pipe and the fifth section pipe are set vertically, the second section pipe and the fourth section pipe are set horizontally, and the third section pipe, the fourth section pipe and the fifth section pipe form an inverted U shape.

[0014] In the above technical solution, the first discharge port is located at the end of the fifth section of the pipeline.

[0015] In the above technical solution, the fifth section of the pipe is a telescopic pipe.

[0016] In the above technical solution, the telescopic pipe is a nested telescopic tail pipe.

[0017] In the above technical solution, the hot gas outlet and the cold gas inlet are located on opposite sides of the forming area.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] 1. Siphon discharge does not rely on mechanical valves, screw conveyors or other active flow control devices. The discharge flow rate can be controlled by the height difference between the first discharge port and the liquid surface of calcium carbide in the storage tank. This avoids the problems of wear, jamming and sealing failure of traditional mechanical flow control components at high temperatures.

[0020] 2. The closed calcium carbide furnace continuous discharge and high-temperature granulation device of the present invention utilizes the siphon effect and its passive flow control characteristics. Without the need for additional power drive, it can form a stable material flow by using the liquid level difference. Moreover, the liquid level difference is positively correlated with the flow rate. Theoretically, the discharge speed can be gradually reduced by the natural decrease of the liquid level difference, which perfectly matches the actual production needs. It is expected to avoid the problems of high temperature wear and insufficient control accuracy of active flow control devices. At the same time, it can realize the adaptive gradual change of the discharge speed as the liquid level in the storage tank decreases, taking into account both reaction stability and working condition adaptability.

[0021] 3. The closed conveying of the siphon bend can prevent the calcium carbide liquid from contacting and oxidizing with air, and reduce dust generation during the granulation process.

[0022] 4. The heat recovery system fully recovers the heat energy of the calcium carbide particles in the collection tank, significantly reducing production costs; the crushed calcium carbide and calcium carbide powder obtained after screening can also be used as raw materials for the dry process of acetylene production. Attached Figure Description

[0023] Figure 1 is a schematic diagram of the structure of a closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid.

[0024] 1-1: Liquid storage tank; 1-2-1: First section of pipeline; 1-2-2: Second section of pipeline; 1-2-3: Third section of pipeline; 1-2-4: Fourth section of pipeline; 1-2-5: Fifth section of pipeline; 1-2-6: First discharge port; 2-1: Cylinder; 2-1-1: Liquid holding area; 2-1-2: Forming area; 2-1-3: Cold gas inlet; 2-1-4: Hot gas outlet; 2-2: Calcium carbide screen; 3: Collection tank. Detailed Implementation

[0025] The technical solution of the present invention will be further described below with reference to specific embodiments.

[0026] Example 1

[0027] As shown in Figure 1, a closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid includes: a continuous discharge unit, a granulation unit, and a collection tank 3 arranged sequentially from top to bottom. The continuous discharge unit includes: a closed storage tank 1-1 and a siphon bend. The storage tank 1-1 is used to store calcium carbide liquid. One end of the siphon bend is connected to the bottom of the storage tank 1-1, and the other end of the siphon bend is the first discharge port 1-2-6. The siphon bend is made of tungsten.

[0028] The granulation unit includes a cylinder 2-1 and a calcium carbide screen 2-2. The bottom of the cylinder 2-1 is open, and the top of the cylinder 2-1 is connected to the first discharge port 1-2-6. The height of the first discharge port 1-2-6 is adjustable. The siphon bend uses the siphon effect to discharge the calcium carbide liquid stored in the liquid storage tank 1-1 from the first discharge port 1-2-6.

[0029] A horizontally arranged calcium carbide sieve 2-2 is installed inside the cylinder 2-1, dividing the cylinder 2-1 into two zones: the section above the calcium carbide sieve 2-2 is the liquid-holding zone 2-1-1, and the section below the calcium carbide sieve 2-2 is the forming zone 2-1-2. The calcium carbide sieve 2-2 is used to allow the calcium carbide liquid passing through the calcium carbide sieve 2-2 to fall into the forming zone 2-1-2 in the form of droplets. A cold gas inlet 2-1-3 is formed in the lower part of the cylinder 2-1 in the forming zone 2-1-2, which is used to introduce cooling gas (nitrogen, argon, or air) into the forming zone 2-1-2, so that the calcium carbide liquid falling into the forming zone 2-1-2 is cooled into calcium carbide particles in the forming zone 2-1-2. A hot gas outlet 2-1-4 is also formed in the upper part of the cylinder 2-1 in the forming zone 2-1-2.

[0030] The opening at the bottom of the cylinder 2-1 is connected to the collection tank 3, and the calcium carbide particles enter the collection tank 3.

[0031] The above-mentioned closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid includes: by adjusting the height difference between the first discharge port 1-2-6 and the liquid level of the calcium carbide liquid in the storage tank 1-1, the flow rate of the calcium carbide liquid passing through the first discharge port 1-2-6 is controlled, so that the calcium carbide liquid in the storage tank 1-1 flows into the liquid holding area 2-1-1 of the granulation unit through the first discharge port 1-2-6 of the siphon bend. There is no need to add additional components such as throttle valves, which can avoid the problems of corrosion, wear or blockage of pump components caused by the use of pump body, extend the service life of equipment and reduce maintenance costs.

[0032] The calcium carbide liquid flowing into the liquid holding area 2-1-1 falls into the forming area 2-1-2 in the form of droplets through the sieve holes of the calcium carbide sieve 2-2. During this process, the calcium carbide liquid falls naturally by gravity and is cooled by the cooling gas. The calcium carbide liquid forms a crust and solidifies from the surface to the inside, forming calcium carbide particles. The calcium carbide particles enter the collection tank 3 through the opening on the bottom surface of the cylinder 2-1.

[0033] When it is necessary to increase the flow rate of calcium carbide liquid discharged through the first outlet 1-2-6, the height of the first outlet 1-2-6 is lowered, the height difference between the first outlet 1-2-6 and the liquid level in the storage tank 1-1 increases, and under the action of gravitational potential energy, the outflow velocity of calcium carbide liquid accelerates, and the discharge volume of the first outlet 1-2-6 per unit time increases; when it is necessary to reduce the flow rate of calcium carbide liquid discharged through the first outlet 1-2-6, the height of the first outlet 1-2-6 is raised, the height difference between the first outlet 1-2-6 and the liquid level in the storage tank 1-1 decreases, and the outflow velocity of calcium carbide liquid slows down.

[0034] When the height of the first discharge port 1-2-6 remains unchanged, as the liquid level in the storage tank 1-1 decreases, the height difference between the first discharge port 1-2-6 and the liquid level in the storage tank 1-1 decreases. Without manual or mechanical intervention, the discharge speed can be smoothly reduced as the liquid level drops, avoiding rapid fluctuations in the furnace liquid level caused by active flow control ("sudden reduction in flow rate" or "emergency stoppage").

[0035] Example 2

[0036] A closed-loop calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid, based on Example 1, includes a siphon bend comprising: a first section pipe 1-2-1, a second section pipe 1-2-2, a third section pipe 1-2-3, a fourth section pipe 1-2-4, and a fifth section pipe 1-2-5 connected in sequence. The first section pipe 1-2-1, the third section pipe 1-2-3, and the fifth section pipe 1-2-5 are vertically arranged, the second section pipe 1-2-2 and the fourth section pipe 1-2-4 are horizontally arranged, and the third section pipe 1-2-3, the fourth section pipe 1-2-4, and the fifth section pipe 1-2-5 form an inverted U-shape. The first discharge port 1-2-6 is located at the end of the fifth section pipe 1-2-5. When the calcium carbide liquid is discharged from the first discharge port 1-2-6, the height of the first discharge port 1-2-6 is lower than the height of the calcium carbide liquid surface in the storage tank 1-1.

[0037] Example 3

[0038] A closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid, based on Example 2, wherein the fifth section pipe 1-2-5 is a telescopic pipe, and the length of the fifth section pipe 1-2-5 is controlled to adjust the height difference between the first discharge port 1-2-6 and the liquid level of the calcium carbide liquid in the storage tank 1-1.

[0039] Preferably, the hot gas outlet 2-1-4 is connected to the heat recovery system (not shown in the figure). The hot gas outlet 2-1-4 and the cold gas inlet 2-1-3 are located on opposite sides of the molding zone 2-1-2. The cooling gas introduced into the cold gas inlet 2-1-3 absorbs heat in the molding zone 2-1-2 and forms a high-temperature gas. The high-temperature gas flows into the heat recovery system through the hot gas outlet 2-1-4. In this process, the cooling gas forms an upward airflow and buoyancy, which is beneficial to the cooling of the calcium carbide liquid.

[0040] The siphon bend is made of refractory material or special steel that can withstand high temperatures of 2300~3000℃.

[0041] Example 4

[0042] A closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid, based on embodiment 3, wherein the fifth section pipe 1-2-5 is a nested telescopic tail pipe, the nested telescopic tail pipe includes: an outer pipe and an inner pipe arranged coaxially, the inner pipe and the outer pipe of the nested telescopic tail pipe are slidably connected, the outer pipe is sleeved outside the inner pipe, the outer pipe is driven by an electric push rod to move axially along the fifth section pipe 1-2-5 (i.e. the push rod of the electric push rod is fixed to the outer pipe), the first discharge port 1-2-6 is located at the bottom end of the outer pipe, and the height difference between the calcium carbide liquid level in the liquid storage tank 1-1 and the first discharge port 1-2-6 is adjusted by adjusting the length of the nested telescopic tail pipe.

[0043] Example 5

[0044] The closed-loop calcium carbide furnace continuous discharge and high-temperature granulation device described in Example 4 is used to process 1-2 tons of calcium carbide liquid at 1900-2100 °C. The calcium carbide sieve 2-2 has a sieve aperture of 30 mm. Room temperature air is introduced into the forming zone 2-1-2 via the cold gas inlet 2-1-3 as cooling gas (the flow rate of the cooling gas introduced through the cold gas inlet 2-1-3 is 800 m / s). 3 The calcium carbide particles obtained by the collection tank 3 have a particle size of about 30 mm and a temperature of 800~1000℃.

[0045] Example 6

[0046] The closed-loop calcium carbide furnace continuous discharge and high-temperature granulation device described in Example 4 is used to process 10-20 tons of calcium carbide liquid at 1900-2100 °C. The calcium carbide sieve 2-2 has a sieve aperture of 60 mm. Room temperature air is introduced into the forming zone 2-1-2 via the cold gas inlet 2-1-3 as cooling gas (the flow rate of the cooling gas introduced through the cold gas inlet 2-1-3 is 1200 m / s). 3 The calcium carbide particles obtained by the collection tank 3 have a particle size of about 60 mm and a temperature of 500~800 ℃.

[0047] Example 7

[0048] The closed-loop calcium carbide furnace continuous discharge and high-temperature granulation device described in Example 4 is used to process 100-200 tons of calcium carbide liquid at 1900-2100 °C. The calcium carbide sieve 2-2 has a sieve aperture of 100 mm. Room temperature air is introduced into the forming zone 2-1-2 via the cold gas inlet 2-1-3 as cooling gas (the flow rate of the cooling gas introduced through the cold gas inlet 2-1-3 is 1500 m / s). 3 The calcium carbide particles obtained by the collection tank 3 have a particle size of approximately 100 mm and a temperature of 300~500 ℃.

[0049] In Examples 5-7, the calcium carbide particles in collection tank 3 are fed into a heat recovery system to exchange heat with nitrogen or argon, forming calcium carbide particles below 100 °C. These particles are then sieved, ultimately yielding calcium carbide particle products and byproducts (crushed calcium carbide and calcium carbide powder). The sieved calcium carbide particle product can be directly supplied to a wet acetylene generator, meeting its reaction rate and safety requirements. The byproducts (crushed calcium carbide and calcium carbide powder) can be used as raw materials for the dry acetylene production process.

[0050] The present invention has been described above by way of example. It should be noted that any simple modifications, alterations or other equivalent substitutions that can be made by those skilled in the art without creative effort without departing from the core of the present invention fall within the protection scope of the present invention.

Claims

1. A closed-loop calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid, characterized in that, include: The continuous discharge unit, granulation unit, and collection tank (3) are arranged sequentially from top to bottom. The continuous discharge unit includes a sealed liquid storage tank (1-1) and a siphon bend. The liquid storage tank (1-1) is used to store calcium carbide liquid. One end of the siphon bend is connected to the bottom of the liquid storage tank (1-1), and the other end of the siphon bend is the first discharge port (1-2-6). The granulation unit includes a cylinder (2-1) and a calcium carbide screen (2-2). The cylinder (2-1) The bottom of the cylinder (2-1) is open, and the top of the cylinder (2-1) is connected to the first discharge port (1-2-6). The height of the first discharge port (1-2-6) is adjustable. The siphon bend uses the siphon effect to discharge the calcium carbide liquid in the storage tank (1-1) from the first discharge port (1-2-6). A horizontally arranged calcium carbide screen (2-2) is installed inside the cylinder (2-1). The calcium carbide screen (2-2) divides the cylinder (2-1) into two areas: the area located at the calcium carbide screen (2-1)... 2-2) The upper cylinder (2-1) is the liquid holding area (2-1-1), and the cylinder (2-1) below the calcium carbide sieve (2-2) is the forming area (2-1-2). The calcium carbide sieve (2-2) is used to allow the calcium carbide liquid passing through the calcium carbide sieve (2-2) to fall into the forming area (2-1-2) in the form of droplets. A cold gas inlet (2-1-3) is formed in the lower part of the cylinder (2-1) in the forming area (2-1-2). The inlet (2-1-3) is used to introduce cooling gas into the forming zone (2-1-2) so that the calcium carbide liquid falling into the forming zone (2-1-2) is cooled into calcium carbide particles in the forming zone (2-1-2); a hot gas outlet (2-1-4) is also formed on the upper part of the cylinder (2-1) located in the forming zone (2-1-2); the opening on the bottom surface of the cylinder (2-1) is connected to the collection tank (3) so that the calcium carbide particles enter the collection tank (3).

2. The closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid according to claim 1, characterized in that, The siphon bend includes: a first section of pipe (1-2-1), a second section of pipe (1-2-2), a third section of pipe (1-2-3), a fourth section of pipe (1-2-4), and a fifth section of pipe (1-2-5) connected in sequence. The first section of pipe (1-2-1), the third section of pipe (1-2-3), and the fifth section of pipe (1-2-5) are set vertically, the second section of pipe (1-2-2) and the fourth section of pipe (1-2-4) are set horizontally, and the third section of pipe (1-2-3), the fourth section of pipe (1-2-4), and the fifth section of pipe (1-2-5) form an inverted U-shape.

3. The closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid according to claim 2, characterized in that, The first discharge port (1-2-6) is located at the end of the fifth section of the pipe (1-2-5).

4. The closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid according to claim 3, characterized in that, The fifth section of the pipe (1-2-5) is a telescopic pipe.

5. The closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid according to claim 4, characterized in that, The telescopic pipe is a nested telescopic tailpipe.

6. The closed calcium carbide furnace continuous discharge and high-temperature granulation device for calcium carbide liquid according to claim 5, characterized in that, Hot gas outlet (2-1-4) and cold gas inlet (2-1-3) are located on opposite sides of the forming zone (2-1-2).

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