Primary acetylene gas production process

Abstract

The invention provides a primary acetylene gas production process, and relates to the technical field of acetylene gas production processes, and the primary acetylene gas production process comprises the following steps: firstly, carrying out on-line screening on a crushed raw material calcium carbide in a specially-made feeding bin, and executing at least three times of'vacuumizing-inert gas filling 'pressure pulse cycles, deeply removing air and moisture adsorbed in pores of the calcium carbide particles; then putting the purified calcium carbide into an acetylene generator provided with a temperature control jacket, and carrying out hydrolysis reaction in a low-temperature interval of 40-65 DEG C; in the reaction process, multi-stage rake teeth of a mechanical stirrer are used for providing strong shearing force to peel off a passivation layer on the surface of calcium carbide, and meanwhile, an external circulating spraying system is matched for eliminating the temperature gradient and local overheating in the reaction kettle. And side reactions such as acetylene polymerization, cracking and oxidation are obviously inhibited.

Description

Technical Field

[0001] This invention belongs to the field of acetylene gas production technology, specifically relating to a primary acetylene gas production process. Background Technology

[0002] Acetylene (C2H2) is an important chemical raw material and carbon source for electronic specialty gases. Its purity directly affects the quality of downstream products and the lifespan of catalysts. Industrially, acetylene is mainly produced by the hydrolysis of calcium carbide, a strongly exothermic reaction.

[0003] In traditional production processes, to overcome the passivating effect of the calcium hydroxide slurry on the surface of calcium carbide, the reaction temperature is usually maintained at 80℃-90℃ or even higher. However, this high-temperature operation mode leads to the generation of thermally induced impurities: the high-temperature environment easily induces the polymerization reaction of acetylene, generating high-carbon polymers such as vinylacetylene and divinylacetylene; at the same time, local overheating can cause acetylene to decompose to generate hydrogen and carbon black, or react with residual oxygen in the system to generate carbon monoxide.

[0004] These impurities are extremely difficult to remove completely in subsequent distillation or adsorption processes. Although lowering the temperature can suppress side reactions, traditional reaction processes and equipment will reduce the reaction rate and affect production capacity at low temperatures of 40℃-60℃. Summary of the Invention

[0005] To overcome the problems in the prior art, the present invention provides a primary acetylene gas production process, which reduces heat-induced impurities in primary acetylene gas production while achieving stable production of primary acetylene gas through synergistic optimization of reaction conditions and equipment structure.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: A primary acetylene gas production process includes the following steps: S1. Vacuum the equipment used in the production process and then replace it with inert gas, repeating this process at least three times. S2. Crush the raw material calcium carbide to a particle size of 10-30mm and remove dust by sieving. S3. Add the calcium carbide prepared in S2 into the feeding hopper, purge and replace it with inert gas, and then vacuum process it. Repeat this process at least three times to remove gas impurities in the hopper and air, dust and moisture attached to the calcium carbide. S4. The calcium carbide purified in S3 is fed from the feeding hopper into the wet acetylene generator. The reaction mixture in the generator is continuously stirred, and the reaction temperature is controlled within the range of 40℃-65℃, so that the calcium carbide reacts with water to generate primary acetylene gas.

[0007] Furthermore, the stirring in S4 includes mechanical stirring and circulating stirring, which are pre-started before calcium carbide is fed in.

[0008] A calcium carbide feeding silo is used in a primary acetylene gas production process. The feeding silo includes a purification chamber, a screening trough, a purging device, a recovery chamber, and a vacuum device. The purging device and the recovery chamber are respectively installed at the top and bottom of the purification chamber. The purging device is connected to an inert gas source, and the recovery chamber is connected to a dust collection cabinet and a recovery pipeline. The screening trough is installed in the purification chamber in an arc-shaped trough shape. The diameter and width of the screening trough correspond to the purification chamber. The trough body has a mesh structure. A rotating shaft is installed at the center of the screening trough, which is connected to a swing motor to drive the screening trough to swing. A feeding port is provided on the side wall of the purification chamber above the screening trough, and a discharge port is provided on the side wall of the recovery chamber below the screening trough. Hydraulically driven baffles are installed on the discharge port and the feeding port. The purification chamber or recovery chamber is connected to the vacuum device, and a discharge pipeline is connected to the outside of the discharge port.

[0009] An acetylene generator is disclosed for use in a primary acetylene gas production process. The acetylene generator includes a reactor, a temperature control jacket, a mechanical stirrer, a circulating stirrer, and a water supply pipeline. The reactor's top cover has a feed inlet at its center, connected to the discharge pipe of the feeding hopper. The reactor's top cover integrates a gas outlet and auxiliary feeding and monitoring interfaces. An annular guide rail is installed at the bottom of the reactor's top cover. The reactor's bottom cross-section is W-shaped. The top of the mechanical stirrer is rotatably connected to the annular guide rail via a slip ring. The lower end of the mechanical stirrer passes through a bearing assembly located at the center of the reactor bottom and connects to the power input end of a stirring motor. At least two evenly distributed discharge ports are provided within the annular groove at the bottom of the reactor. A temperature control jacket is installed on the outer wall of the reactor. The input end of the circulating stirrer is connected to the bottom of the reactor, and the output end is connected to the top of the reactor. The output end of the water supply pipeline is located below the highest water level line within the reactor.

[0010] Furthermore, the mechanical agitator includes a stirring shaft, a stirring rake, and a distributor; the lower end of the stirring shaft is connected to the power input end of the stirring motor, and the distributor is installed at the top of the stirring shaft. The distributor is conical and is positioned below the calcium carbide inlet. The calcium carbide is thrown into the outer edge area of ​​the reactor near the reactor wall through the inclined surface of the distributor. A baffle is evenly arranged around the distributor axis, and the baffle is connected to a slip ring through a connecting rod; the stirring rake is radially mounted on the stirring shaft and includes converging rake teeth, expanding rake teeth, and horizontal rake teeth. At least one set of converging rake teeth and expanding rake teeth is installed sequentially below the liquid surface of the reactor. The horizontal rake teeth are evenly arranged below the expanding rake teeth, and the rake teeth of the stirring rake at the bottom of the reactor are arranged in the opposite direction towards the annular groove at the bottom of the reactor.

[0011] Furthermore, at least one set of circulating agitators is evenly distributed and installed on the reactor. The circulating agitator includes a circulating pump, a water pumping pipe, an output pipe, and a spray plate. The circulating pump is mounted on a frame outside the reactor. The input end of the water pumping pipe is located in the central area of ​​the bottom of the reactor and is fitted with a filter cover. The output end of the water pumping pipe is connected to the input end of the circulating pump. The input end of the output pipe is connected to the output end of the circulating pump, and the other end is connected to the input end of the spray plate. The spray plate is installed below the top cover of the reactor and has at least two sets of nozzles. One set of nozzles corresponds to the material drop area of ​​the distributor, and the other set of nozzles faces the central area of ​​the reactor.

[0012] Furthermore, the water supply pipeline includes a main water supply pipe, branch water distribution pipes, and a mixer; the water supply pipeline is arranged in a ring around the outside of the reactor and connected to a water source, and the branch water distribution pipes are evenly distributed between the first set of converging rake teeth and expanding rake teeth below the liquid surface; the input end of the branch water distribution pipe is connected to the main water supply pipe, and the output end of the branch water distribution pipe is located in the outer edge material drop area inside the reactor, and a mixer is installed on the output end of the branch water distribution pipe; the mixer rotates under the drive of the input water flow to agitate and mix the material drop.

[0013] The beneficial effects of this invention are: 1. This invention strictly controls the reaction temperature to block the polymerization and cracking pathways of acetylene. Combined with a vacuum pulse deep degassing process before feeding, it eliminates air (oxygen, nitrogen) and moisture introduced by the raw materials. Compared with traditional high-temperature processes, the primary acetylene gas produced by this invention has lower thermal impurities such as hydrogen, methane, and carbon monoxide, producing a high-purity primary gas source, laying a solid foundation for the production of electronic-grade acetylene.

[0014] 2. This invention designs a synergistic stirring system of mechanical shearing and circulating spraying. The synergistic effect of the two enables the reaction to proceed rapidly and stably in a low-temperature environment, ensuring a calcium carbide conversion rate and gas production rate comparable to high-temperature processes. Attached Figure Description

[0015] Figure 1 This is a flowchart of the process flow of the present invention; Figure 2 This is an overall structural diagram of the high-purity acetylene preparation system of the present invention; Figure 3 This is a front view of the high-purity acetylene preparation system of the present invention; Figure 4 This is a side view of the high-purity acetylene preparation system of the present invention; Figure 5 This is a three-dimensional structural diagram of the internal structure of the feeding hopper of the present invention; Figure 6 This is a plan view of the internal structure of the feeding hopper of the present invention; Figure 7 This is a side view of the feeding hopper structure of the present invention; Figure 8 This is an overall structural diagram of the acetylene generator of the present invention; Figure 9 This is a front view of the acetylene generator of the present invention; Figure 10 This is a bottom view of the acetylene generator of the present invention; Figure 11 This is a three-dimensional structural diagram of the internal structure of the acetylene generator of the present invention; Figure 12 This is a plan view of the internal structure of the acetylene generator of the present invention; Figure 13 This is a half-sectional view of the acetylene generator of the present invention; Figure 14 This is a cross-sectional structural diagram of the acetylene generator housing of the present invention; Figure 15 This is a three-dimensional structural diagram of the internal structure of the acetylene generator housing of the present invention; Figure 16 This is a three-dimensional structural diagram of the mechanical stirrer of the present invention; Figure 17 This is a front view structural diagram of the mechanical stirrer of the present invention; Figure 18 This is an overall structural diagram of the circulating stirrer of the present invention; Figure 19 The spectrum of the standard material used for PDHID analysis calibration in this invention (sensitivity 10) -9 ); Figure 20 The chromatogram of the product in Example 1 of this invention analyzed using a GC126 PDHID detector (sensitivity 10). -8 ); Figure 21 The chromatogram of the product of Comparative Example 1 of this invention analyzed using a GC126 PDHID detector (sensitivity 10). -8 ); Figure 22 The chromatogram of the product of Comparative Example 2 of this invention was analyzed using a GC126 PDHID detector. Figure 23 This is the spectrum of the standard material used for analysis and calibration of the A91PLUS in this invention; Figure 24 The chromatogram of the product in Example 1 of this invention analyzed using an A91PLUS FID detector; Figure 25 The chromatogram of the product of Comparative Example 1 of this invention was analyzed using an A91PLUS FID detector. Figure 26 The chromatogram of the product of Comparative Example 2 of this invention is obtained by analysis using an A91PLUS FID detector.

[0016] The diagram shows the following components: 1-Feeding hopper, 11-Purification chamber, 12-Screening trough, 13-Purge device, 14-Recovery chamber, 15-Vacuum device, 16-Discharge port, 17-Feeding port, 18-Oscillating motor, 19-Discharge pipe; 2-Acetylene generator, 21-Reaction vessel, 211-Feeding port, 212-Annular guide rail, 213-Slurry discharge port, 214-Slip ring, 22-Temperature control jacket; 3-Stirring... Mixing motor; 4-Mechanical mixer, 41-Mixing shaft, 42-Mixing rake, 421-Collapsing rake teeth, 422-Expanding rake teeth, 423-Horizontal rake teeth, 43-Distributor, 431-Baffle plate; 5-Circulating mixer, 51-Circulating pump, 52-Water pumping pipeline, 53-Output pipeline, 54-Spraying disc; 6-Water supply pipeline, 61-Main water supply pipe, 62-Water distribution branch pipe, 63-Mixer. Detailed Implementation

[0017] To make the objectives, technical solutions, and beneficial effects of the present invention clearer, the preferred embodiments of the present invention will be described in detail below to facilitate understanding by those skilled in the art.

[0018] This invention discloses a primary acetylene gas production process and a supporting production system. The system integrates a feeding hopper 1 with online fine screening and dynamic purification functions and a low-temperature acetylene generator 2 with synergistic dual-mode stirring technology. Feeding hopper 1 ensures that the calcium carbide raw materials entering the reaction core have consistent physical characteristics (particle size 10-30mm, dust, moisture, and air content), laying a solid foundation for the stable and efficient conduct of subsequent reactions. Acetylene generator 2 achieves low-temperature reaction (40℃-65℃) through the synergistic action of mechanical stirrer 4 and circulating stirrer 5. In traditional processes, although low temperature is beneficial for suppressing side reactions, reducing calorific value impurities, and improving product purity, it leads to a decrease in reaction rate. The dual-mode stirring system of this invention maintains reaction efficiency while ensuring low-temperature reaction and reducing calorific value impurities of acetylene gas through solid-liquid interface mass transfer (mechanical stirrer 4) and macroscopic fluid mixing and heat management in the reactor (circulating stirrer 5).

[0019] I. Feeding bin design Please see Figures 2 to 6 The feeding hopper 1 includes an upper purification chamber 11 and a lower recovery chamber 14. The side wall of the purification chamber 11 is provided with a feeding port 17 for loading pre-crushed calcium carbide raw materials. The side wall of the recovery chamber 14 is provided with a discharge port 16 for conveying the processed qualified calcium carbide to the downstream acetylene generator 2. Both the feeding port 17 and the discharge port 16 are equipped with hydraulically driven baffles. The baffles can provide airtight seals, so that the purification chamber 11 and the recovery chamber 14 can be completely isolated from the external environment and from each other during operation. The interior of the purification chamber 11 is an arc-shaped trough 12. The trough body of the trough 12 is made of a mesh with a aperture (<10mm). The size of the trough 12 matches the inner cavity of the purification chamber 11. A rotating shaft is installed in the center of the trough 12. The rotating shaft is connected to an external swing motor 18 through a transmission mechanism. When the swing motor 18 is started, it can drive the trough 12 to swing back and forth, thereby realizing dynamic screening of the calcium carbide raw material placed on it. The screening function is built into the sealed cavity to avoid secondary pollution. The feeding hopper 1 also integrates a gas treatment system. A purging device 13 is installed on the top of the purification chamber 11. The purging device 13 is connected to an external high-purity inert gas (99.999% nitrogen or argon) source through a pipeline. The cavity of the purification chamber 11 or the recovery chamber 14 is connected to a pipeline interface of a vacuum pumping device 15. The purging device 13 and the vacuum pumping device 15 work together to enable the system to perform repeated "vacuuming and gas filling" pressure pulse cycles on the calcium carbide in the purification chamber 11, thereby removing impurities (nitrogen, oxygen, argon and moisture) adsorbed on the surface and pores of the calcium carbide particles. The recovery chamber 14 is connected to a dust collection cabinet and a recovery pipeline. During the screening process, calcium carbide dust with too small a particle size will pass through the mesh of the screening trough 12 and fall into the recovery chamber 14, where it will be safely collected by the dust collection cabinet in a sealed manner. This prevents the dust from entering the subsequent reactor and eliminates the safety hazard of local overheating caused by dust coming into contact with water.

[0020] Operating procedures for feeding hopper 1: Loading and screening: Industrial-grade calcium carbide raw materials, which have been pre-crushed to have a nominal particle size in the range of 10-30mm, are loaded into the screening trough 12 in the purification chamber 11 through the feeding port 17, and then the sealing baffle of the feeding port 17 is closed; the oscillating motor 18 is started to start the oscillation of the screening trough 12, and the calcium carbide particles roll and rub against each other in the trough; the oscillation of the screening trough 12 can further remove residual dust generated during the transfer and loading process, and, in conjunction with the subsequent dynamic purification steps, help remove impurities trapped between particles; Dynamic purification: After screening, the control system starts the vacuum pumping device 15 to evacuate the interior of the purification chamber 11 to a vacuum state (below 100Pa); then the vacuum pipeline is closed, the valve connected to the purging device 13 is opened, and high-purity inert gas is introduced into the purification chamber 11 until the pressure is restored to slightly higher than atmospheric pressure (0.15MPa); the process of vacuuming and inert gas filling constitutes a pressure pulse cycle, which will be repeated at least three times according to process requirements. The drastic pressure change can desorb impurities on the surface of calcium carbide. Discharge: After completing the preset number of purification cycles, the sealing baffle of the discharge port 16 is opened, and the calcium carbide enters the downstream acetylene generator 2 through the discharge pipe 19 under the action of gravity. The integrated feeding hopper 1 integrates multiple pretreatment steps (screening, dust removal, and purification) that were originally scattered and prone to pollution, ensuring that each batch of calcium carbide raw materials entering the reactor is highly consistent.

[0021] Acetylene generator design like Figure 7 , Figure 8 and Figure 13 As shown, the main body of the acetylene generator 2 is a reaction vessel 21. The reaction temperature of the reaction liquid inside the vessel is maintained at 40℃-65℃, which ensures reaction efficiency while suppressing the generation of overheated side reaction impurities (hydrogen, methane, carbon monoxide, ethane, ethylene). The acetylene generator 2 includes the following components: The temperature control jacket 22 provides cooling capacity through circulating cooling medium (chilled water). Combined with the design of the material distributor 43, the calcium carbide sent out by the feeding bin 1 is evenly thrown into the outer edge area of ​​the reactor 21 near the reactor wall. This area is close to the temperature control jacket 22, so that the reaction heat energy is removed as quickly as possible. The inward rake teeth 421 and outward rake teeth 422 of the mechanical stirrer 4 disperse the calcium carbide particles from the outside to the inside and then outward, preventing local accumulation and overheating; at the same time, the circulating stirrer 5 promotes the macroscopic circulation of the reaction liquid in the reactor, keeping the temperature field in the reactor uniform. Water supply line 6 can replenish cold water to the active reaction zone, enabling rapid temperature control; The W-shaped design at the bottom of the reactor and the evenly distributed discharge ports 213 ensure uniform discharge of slurry fluid, stabilize the flow field inside the reactor, and ensure dynamic balance between discharge volume and water inlet and spray volume through the control system, thereby achieving stable control of total heat and material inside the reactor. The reactor 21 has a feed inlet 211 at the center of the top cover, which is airtightly connected to the discharge pipe 9 of the upstream feeding silo 1. The top cover also integrates a gas outlet and monitoring and auxiliary interfaces. The bottom cross section of the reactor 21 is W-shaped, forming an annular groove at the bottom. The annular groove provides a natural settling and aggregation area for the high-density calcium hydroxide slurry generated by the reaction, and provides a movement trajectory and working space for the bottom rake teeth of the mechanical agitator 4 described later. At least two discharge ports 213 are evenly arranged in the annular groove to periodically or continuously discharge the waste calcium carbide slag slurry, so as to achieve long-term stable operation of the system. The mechanical stirrer 4 is driven by a stirring shaft 41 located on the central axis of the reaction vessel 21, and the power comes from the stirring rod motor 3 at the bottom of the vessel. The mechanical stirrer 4 includes: Distributor 43: Installed at the top of the stirring shaft 41, directly below the calcium carbide inlet 211, the distributor 43 is conical in shape and has baffles 431 evenly distributed on its surface. When the purified calcium carbide falls from the feeding bin 1, it first comes into contact with the rotating distributor 43. The conical slope of the distributor 43 uses centrifugal force to evenly throw the block calcium carbide into the outer edge area of ​​the reactor 21 near the reactor wall, avoiding the accumulation of calcium carbide in the center of the reactor, preventing hot spots caused by excessive local reaction, and ensuring that the raw materials are evenly distributed closer to the temperature control jacket on the reactor cross section. Multi-stage stirring rake 42: The stirring rake 42 performs stirring and scraping functions. The stirring rake 42 is radially mounted on the stirring shaft 41 and includes three different types and functions of rake teeth: The converging rake teeth 421 and the expanding rake teeth 422 are installed in groups in the reaction area below the reaction liquid surface. When rotating, the tilt angle generates a flow field in the radial and axial directions, which exerts strong shearing, collision and tumbling action on the calcium carbide particles suspended in the liquid. Through continuous mechanical force, the passivation layer generated during the reaction and wrapped on the surface of the calcium carbide is scraped and washed away, exposing the unreacted calcium carbide. This ensures that water can continuously contact fresh calcium carbide and solves the problem of low reaction rate at low temperature. Horizontal rake teeth 423: The horizontal rake teeth 423 are installed below the converging rake teeth 421 and the expanding rake teeth 422 to maintain the suspension of the lower layer of slurry. The horizontal rake teeth 423 located in the W-shaped groove at the bottom of the reactor are installed in the opposite direction to actively and continuously push the settled thick slurry towards the discharge port 213 to prevent dead zones and blockages at the bottom of the reactor. The circulating agitator 5 complements the mechanical agitator 4 and includes a circulating pump 51, a water pumping pipe 52, an output pipe 53, and a spray plate 54. The circulating pump 51 is installed outside the reactor 21. It draws the reaction liquid from the central area at the bottom of the reactor 21 through the water pumping pipe 52. The inlet of the water pumping pipe 52 is equipped with a filter cover to prevent solid particles from entering the pump body. After being pressurized by the pump, the reaction liquid is delivered to the spray plate 54 under the top cover of the reactor 21 through the output pipe 53. This achieves rapid macroscopic mixing of the liquid volume in the entire reactor, eliminates temperature gradients, and ensures that the cooling effect of the temperature control jacket 22 is uniform and rapidly transferred in the reactor, thus ensuring the control of the overall temperature. The spray plate 54 is equipped with two sets of nozzles. One set of nozzles is aimed at the calcium carbide dropping area below the distributor 43. When new calcium carbide is thrown towards the outer edge of the reactor wall, the water flow sprayed from this set of nozzles will immediately wet it and provide initial reaction water volume and cooling, suppressing the violent reaction when dry calcium carbide enters the water. The other set of nozzles sprays towards the central area of ​​the reactor 21, forming a top-down central flow, which interacts with the radial and axial flow field generated by the mechanical stirrer 4, enhances the mixing effect and breaks the bubbles and scum formed on the liquid surface. To match the reaction consumption, fresh water needs to be continuously replenished into the reactor 21. The water supply pipeline 6 includes a main water supply pipe 61 arranged in a ring outside the reactor 21, and water distribution branch pipes 62 evenly distributed from the main pipe. The outlet of the water distribution branch pipe 62 is arranged below the liquid surface, in the outer edge of the material drop area between the first set of converging rake teeth 421 and expanding rake teeth 422, so that fresh water is directly injected into the area where the reaction is most active and the new raw materials are most concentrated. Each water distribution branch pipe 62 is also equipped with a mixer 63 at the output end, which rotates on its own under the drive of the input water flow, causing disturbance and mixing in the material drop area, so that the newly added water and calcium carbide can be quickly and fully mixed.

[0022] Production process flow Reference Figure 1 The process flow of this invention is as follows: S1. System Pretreatment: For equipment that comes into contact with process gases, including but not limited to feed hopper 1, acetylene generator 2 and connecting pipelines, a purification procedure is performed, including: first, using a vacuum pump to evacuate the equipment to a high vacuum state, then filling it with high-purity inert gas (such as nitrogen) to positive pressure, and then evacuating the vacuum again. This vacuuming, filling and replacement cycle needs to be repeated at least three times until the residual oxygen and moisture concentration in the system meets the process requirements. S2. Calcium carbide preparation: Select qualified industrial-grade calcium carbide as raw material. First, crush the raw calcium carbide to control the particle size between 10-30mm. Then, remove most of the calcium carbide dust generated during the crushing process through screening. S3. Feeding and purification: The calcium carbide prepared in step S2 is fed into the screening trough 12 of the feeding hopper 1 through the feeding port 17. Dynamic purification is performed on this batch of calcium carbide in the closed environment of the feeding hopper 1, including online secondary screening and dust removal through the swing of the screening trough 12, and at least three pulse cycles of vacuuming and nitrogen filling pressure, so that the calcium carbide particles themselves and most of the impurities attached to them are removed. S4, Acetylene Generation: Before feeding, the mechanical stirrer 4 and circulating stirrer 5 in the acetylene generator 2 are started in advance, and an appropriate amount of process water is injected into the reaction vessel 21. The cooling circulation of the temperature control jacket 22 is started to adjust and stabilize the water temperature at 40℃-65℃. The calcium carbide purified in S3 is fed into the acetylene generator 2 from the feeding bin 1. The calcium carbide is evenly distributed under the action of the distributor 43 and reacts with the water in the vessel after double stirring to generate primary acetylene gas.

[0023] Throughout the reaction process, dual-mode stirring and temperature control circulation are continuously operated to ensure a stable and efficient reaction and to suppress the formation of thermal impurities.

[0024] Example 1 Equipment and raw material preparation: A reaction system consisting of a feeding hopper 1 and an acetylene generator 2 is adopted. A batch of industrial calcium carbide is selected, and after crushing and screening, the portion with a particle size of 10-30mm is taken as raw material. S1. Perform three vacuum cycles to 100Pa on the feeding and reaction system, and then purge with 99.999% pure nitrogen to 0.15MPa for purification. S2 & S3: 100 kg of calcium carbide with a particle size between 10-30 mm is loaded into the feeding hopper 1. The swing motor 18 is started for online dust removal. Then, the purification chamber 11 containing calcium carbide is subjected to three pressure pulse cycles of vacuuming to 100 Pa and filling with high-purity nitrogen to 0.15 MPa. S4. Inject process water into acetylene generator 2, and precisely control the water temperature at 55±2℃ through temperature control jacket 22. Pre-start mechanical agitator 4 at a speed of 150RPM, and simultaneously start circulating agitator 5 to make the flow rate of circulating pump 51 reach 60m³ / h. 3 / h, the purified calcium carbide is put into the generator to react and generate primary acetylene gas.

[0025] Product Analysis: The primary acetylene gas produced was analyzed, and the impurity content results are recorded in Table 1.

[0026] Comparative Example 1: Traditional Craftsmanship The operation follows the traditional process flow, specifically: industrial-grade 50-80mm block calcium carbide that has not undergone special purification is reacted using traditional feeding equipment and an acetylene generator. The reaction temperature is controlled at 85±5℃. The primary acetylene gas produced is analyzed, and the impurity content results are recorded in Table 1.

[0027] Comparative Example 2: Comparative Example 2 uses the same acetylene generator as Comparative Example 1 to prepare acetylene, with the same calcium carbide particle size and reaction temperature as in Example 1.

[0028] IV. Experimental Analysis Analytical methods The gaseous impurity content of the products in Example 1, Comparative Example 1, and Comparative Example 2 was analyzed by gas chromatography. The results are summarized in Table 1, and the specific methods are as follows: 1. Analysis of impurities such as hydrogen, carbon monoxide, and carbon dioxide A gas chromatograph with a GC126 PDHID detector was used.

[0029] Hydrogen and carbon monoxide impurities in high-purity acetylene were analyzed using a GC126 PDHID gas chromatograph. Quantification was performed using the external standard method. The analytical conditions were as follows: high-purity helium (≥99.999%) was purified and used as the carrier gas; a 5-valve, 6-column system was used. Column 1: 2m*3.2mm 401 deoxygenated column; Column 2: 2m*3.2mm H / R pre-separation column; Column 3: 4.5m*3.2mm H / T column; Column 4: 2m*3.2mm H / Q column; Column 5: 2m*3.2mm 5A1 column; Column 6: 2m*3.2mm 5A2 column. Column temperature: 55℃; deoxygenated column: 60℃; pre-sheared column: 60℃; PDHID detector: 120℃. The quantitative standard uses helium produced by DAT as the base standard, with an impurity content of about 5 ppm. Certificate number GBW(E)061538, bottle number: 163241505064. The analysis results are shown below. Figure 20 , Figure 21 , Figure 22 .

[0030] 2. Analysis of hydrocarbon impurities (methane, ethane, ethylene) Methane, ethane, and ethylene impurities in high-purity acetylene were analyzed using an A91PLUS gas chromatograph with an FID detector. An Agilent HP-AL / S (25m 0.32mm 8μm) capillary column was used with valve injection. The detection conditions were as follows: purified high-purity nitrogen as carrier gas; injection port temperature 150 ℃, split ratio 5:1; column temperature 50 ℃, programmed temperature increase 5 ℃ / min to 130 ℃, column flow rate 1.5 mL / min; detector 200 ℃, hydrogen flow rate 40 mL / min, air flow rate 400 mL / min; and make-up gas flow rate 20 mL / min. The calibration reference materials used are nitrogen-containing methane, ethane, ethylene, acetylene, propane, propylene, cyclopropane, propyne, propadiene, n-butane, isobutane, 1-butene, isobutene, trans-2-butene, cis-2-butene, 1,3-butadiene, and isopentane reference materials produced by Dalian Date, certificate number GBW(E)060157, bottle number: L181819256; The analysis results are shown below. Figure 24 , Figure 25 , Figure 26 .

[0031] Table 1. Analysis of primary acetylene thermally induced gas impurities. 3. Reaction efficiency test Reactants: 1000 kg of the same batch of calcium carbide was loaded into the reactors of Example 1 and Comparative Example 1; Reaction conditions: Example 1 was maintained at 55±2℃, and Comparative Example 1 was maintained at 85±5℃; except for temperature and stirring system, other corresponding conditions, such as initial water volume, were kept consistent. Data acquisition: After the reaction begins, the flow rate and cumulative production of acetylene are monitored and recorded at the reactor outlet using an online gas flow meter at 5-minute intervals until the gas production rate drops to near zero. Data analysis: Based on the collected data, the total gas production yield and reaction endpoint time are calculated respectively.

[0032] Table 2 Comparison of Reaction Efficiency Total gas production: The total volume of acetylene produced from a fixed mass of calcium carbide after the experiment. Reaction endpoint time: The time required to reach a total gas yield of 95%.

[0033] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.

Claims

1. A primary acetylene gas production process, characterized in that, Includes the following steps: S1. Vacuum the equipment used in the production process and then replace it with inert gas, repeating this process at least three times. S2. Crush the raw material calcium carbide to a particle size of 10-30mm and remove dust by sieving. S3. Add the calcium carbide prepared in S2 into the feeding hopper, purge and replace it with inert gas, and then vacuum process it. Repeat this process at least three times to remove gas impurities in the hopper and impurities attached to the calcium carbide. S4. The calcium carbide purified in S3 is fed into the wet acetylene generator from the feeding hopper. The reaction mixture in the generator is continuously stirred, and the reaction temperature is controlled within the range of 40℃-65℃, so that the calcium carbide reacts with water to generate primary acetylene gas.

2. The primary acetylene gas production process according to claim 1, characterized in that, The stirring in S4 includes mechanical stirring and circulating stirring, which are pre-started before calcium carbide is fed in.

3. A calcium carbide feeding bin, characterized in that, The primary acetylene gas production process described in claim 1 is provided, wherein the feeding hopper (1) includes a purification chamber (11), a screening trough (12), a purging device (13), a recovery chamber (14), and a vacuum device (15). The purging device (13) and the recovery chamber (14) are respectively installed at the top and bottom of the purification chamber (11). The purging device (13) is connected to the inert gas source, and the recovery chamber (14) is connected to the dust collection cabinet and the recovery pipeline. The screening trough (12) is installed in the purification chamber (11) in an arc-shaped trough. The diameter and width of the screening trough (12) correspond to those of the purification chamber (11). The trough body of the screening trough (12) is a mesh structure. A rotating shaft is installed in the center of the screening trough (12) to connect to a swing motor (18) to drive the screening trough (12) to swing. A feeding port (17) is provided on the side wall of the purification chamber (11) above the screening trough (12). A discharge port (16) is provided on the side wall of the recovery chamber (14) below the screening trough (12). Hydraulically driven baffles are installed on the discharge port (16) and the feeding port (17). The purification chamber (11) or recycling chamber (14) is connected to the vacuum device (15), and the discharge port (16) is connected to the discharge pipe (19) on the outside.

4. An acetylene generator, characterized in that, The acetylene generator (2) is applied to the primary acetylene gas production process described in claim 1, and includes a reaction vessel (21), a temperature control jacket (22), a mechanical stirrer (4), a circulating stirrer (5), and a water supply pipeline (6). The reactor (21) has a feed inlet (211) at the center of its top cover, which is connected to the discharge pipe (19) of the feeding bin (1). The top cover of the reactor (21) integrates a gas outlet and auxiliary feeding and monitoring interfaces. The bottom of the top cover of the reactor (21) is provided with an annular guide rail (212). The bottom cross section of the reactor (21) is W-shaped. The top of the mechanical stirrer (4) is rotatably connected to the annular guide rail (212) through a slip ring (214). The lower end of the mechanical stirrer (4) passes through the reactor. The bearing assembly at the bottom center is connected to the power input end of the stirring motor (3); at least two evenly distributed slurry discharge ports (213) are provided in the annular groove at the bottom of the reactor (21), and a temperature control jacket (22) is installed on the outer wall of the reactor (21); the input end of the circulating stirrer (5) is connected to the bottom of the reactor (21), and the output end of the circulating stirrer (4) is connected to the top of the reactor (21); the output end of the water supply pipeline (6) is located below the highest water level line in the reactor (21).

5. The acetylene generator according to claim 4, characterized in that, The mechanical mixer (4) includes a mixing shaft (41), a mixing rake (42), and a distributor (43). The lower end of the stirring shaft (41) is connected to the power input end of the stirring motor (3). A feeder (43) is installed at the top of the stirring shaft (41). The feeder (43) is conical and is positioned below the calcium carbide inlet (211). The calcium carbide is thrown into the outer edge area of ​​the reactor (21) near the reactor wall through the inclined surface of the feeder (43). A partition plate (431) is evenly arranged around the axis of the feeder (43). The partition plate (431) is connected to the slip ring (214) through a connecting rod. The stirring rake (42) is radially mounted on the stirring shaft (41) and includes a converging rake tooth (421), an expanding rake tooth (422), and a horizontal rake tooth (423). At least one set of converging rake teeth (421) and expanding rake teeth (422) are installed in sequence below the liquid surface of the reactor (21). The horizontal rake teeth (423) are evenly arranged below the expanding rake teeth (422). The rake teeth of the stirring rake (42) at the bottom of the reactor (21) are arranged in the opposite direction towards the annular groove at the bottom of the reactor.

6. The acetylene generator according to claim 4, characterized in that, At least one set of circulating agitators (5) is evenly installed on the reactor (21). The circulating agitator (5) includes a circulating pump (51), a water pumping pipeline (52), an output pipeline (53), and a spray plate (54). The circulating pump (51) is mounted on a frame outside the reactor (21); The input end of the pumping pipe (52) is located in the central area at the bottom of the reactor (21) and a filter cover is installed thereon. The output end of the pumping pipe (52) is connected to the input end of the circulating pump (51). The input end of the output pipeline (53) is connected to the output end of the circulating pump (51), and the other end is connected to the input end of the spray plate (54); The spray plate (54) is installed below the top cover of the reactor (21). The spray plate (54) is equipped with at least two sets of nozzles, one set of nozzles corresponding to the material drop area of ​​the feeder (43), and the other set of nozzles facing the central area of ​​the reactor (21).

7. The acetylene generator according to claim 4, characterized in that, The water supply pipeline (6) includes a main water supply pipe (61), a branch water distribution pipe (62), and a mixer (63). The water supply pipeline (6) is arranged in a ring outside the reactor (21) to connect to the water source, and the water distribution branch pipe (62) is evenly distributed between the first set of converging rake teeth (421) and expanding rake teeth (422) below the liquid surface; The input end of the water distribution branch pipe (62) is connected to the main water supply pipe (61), and the output end of the water distribution branch pipe (62) is located in the outer edge material drop area inside the reactor (21). A mixer (63) is installed on the output end of the water distribution branch pipe (62). The mixer (63) rotates under the influence of the input water flow to agitate and mix the falling material.

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