A sodium cyanide reaction kettle

Abstract

The utility model discloses a sodium cyanide reation kettle belongs to chemical equipment technical field. The reation kettle includes kettle body, kettle cover and stirring shaft, and stirring shaft is sealedly connected with kettle body through double end face mechanical seal, and the shaft is equipped with middle layer open type paddle and bottom layer anchor type paddle, improves stirring efficiency. The kettle body outside is equipped with sealed shell, and sets up multilayer spiral pipe for temperature control between shell and kettle body, and is connected nitrogen source and detection table through Y type pipeline, realizes inert atmosphere protection and pressure monitoring. The kettle body is connected with kettle cover flange connection and adopts elastic ring radial reinforcement seal. The utility model discloses through multiple sealing structure effectively prevents the leakage of toxic gas, and the combined type stirring improves the mixing effect, and nitrogen protection and pressure monitoring system enhance security, especially suitable for the reaction process of sodium cyanide and other toxic, strong corrosive material.

Description

Technical Field

[0001] This utility model relates to the field of chemical equipment technology, specifically to a sodium cyanide reaction vessel. Background Technology

[0002] In the field of chemical equipment, reaction vessels are a commonly used type of chemical equipment. However, for sodium cyanide, a special chemical substance, due to its toxicity and other properties, its reaction process often involves high temperature, high pressure, and strong corrosiveness. Commonly used reaction vessels cannot meet the specific requirements of sodium cyanide and have the following drawbacks: 1. Insufficient sealing performance: Most traditional reactors use single-end mechanical seals, which can easily lead to the leakage of toxic gases and cause injury or death to workers.

[0003] 2. Low stirring efficiency: Traditional reaction vessels use a single type of impeller, which is difficult to meet the solid-liquid phase mixing and mass transfer requirements often encountered in the sodium cyanide reaction process.

[0004] 3. Insufficient safety protection measures: Weak safety protection measures and improper operation can easily lead to the explosion of the reaction vessel.

[0005] 4. Low heat exchange efficiency: Traditional reactors use simple jackets with limited heat exchange area and low temperature control accuracy.

[0006] Therefore, for the reaction vessel of sodium cyanide, a special substance, there is an urgent need for a sodium cyanide reaction vessel with good sealing performance, high stirring efficiency, sufficient safety protection measures and high heat exchange efficiency, taking into account its special properties. Utility Model Content

[0007] The technical problems to be solved by this invention are that traditional reaction vessels have insufficient sealing performance, low stirring efficiency, insufficient safety protection measures, and low heat exchange efficiency.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: a sodium cyanide reaction vessel, including a vessel body, a vessel cover above the vessel body, and a stirring shaft disposed in the vessel body. The top end of the stirring shaft passes through the top flange of the vessel cover and is connected to a motor, and is sealed to the vessel body through a double-end mechanical seal. The motor is fixed to the top of the vessel cover. The stirring shaft is provided with a middle layer of open blades and a bottom layer of anchor blades along the axial direction. The vessel body has an outer shell with the same shape as the vessel body, and the outer shell is welded to the flange at the top of the vessel body; the bottom of the vessel body is provided with a discharge port that passes through the outer shell; a spiral tube is provided on the outside of the vessel body and inside the outer shell, and the spiral tube surrounds the vessel body. The spiral tube has a multi-layer spiral structure. The inlet pipe of the spiral tube is connected to an external refrigerant or heat source, and the outlet pipe of the spiral tube is connected to an external heat exchanger. The vessel body and the outer shell are also sealed, and the outer shell has a through hole for connecting to a Y-shaped pipe. The Y-shaped pipe is connected to the outer shell with a flow regulating valve, and the other two ends are connected to a nitrogen cylinder and a test gauge, respectively.

[0009] As a further embodiment of this utility model: bearings are provided at both ends of the stirring shaft, the bottom bearing is a radial bearing, which is a self-lubricating ceramic bearing, and the top bearing is a thrust bearing, which is a double-direction angular contact ball bearing.

[0010] As a further embodiment of this utility model: the inner wall of the reactor is made of 316L stainless steel lined with fluoropolymer, the substrate of the stirring shaft is made of 316L stainless steel, and the surface is overlaid with Stellite alloy.

[0011] As a further embodiment of this utility model: the dynamic ring of the double-end mechanical seal at the top of the stirring shaft is made of silicon carbide, the stationary ring is made of graphite, and the surface roughness Ra of the contact end of the dynamic ring and the stationary ring is ≤0.8μm.

[0012] As a further embodiment of this utility model: after the vessel body is connected to the vessel cover flange, it is reinforced and sealed radially with an elastic collar.

[0013] As a further embodiment of this utility model: the kettle cover is provided with a manhole, a main feed inlet, an auxiliary feed inlet and a catalyst feed inlet, all of which are flange quick-release structures, and the kettle cover is also provided with a pressure gauge port.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows: 1. This utility model ensures the sealing of the reactor through a double-end mechanical seal, effectively preventing the leakage of toxic gases during the sodium cyanide reaction. The radial preload of the elastic ring after flange connection eliminates the assembly gap, forming a secondary sealing barrier to prevent minor leaks caused by vibration or thermal expansion and contraction.

[0015] 2. This utility model enhances radial flow by using an open blade in the middle layer and an anchor blade at the bottom layer to promote the agitation of materials at the bottom of the reactor, thereby improving the stirring efficiency of the sodium cyanide reaction process.

[0016] 3. This utility model uses a nitrogen pipeline built into the outer shell to regulate the pressure of the reactor body and prevent the leakage of toxic gases, thus preventing the reactor from exploding. Real-time monitoring can effectively prevent the reactor from exploding and improve the safety of the reactor.

[0017] 4. This utility model adopts a multi-layer spiral tube structure channel, which improves the heat exchange efficiency and precisely controls the reaction temperature by injecting refrigerant or heat medium into the spiral tube for heat exchange. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a partial structural schematic diagram of a sodium cyanide reaction vessel according to the present invention.

[0019] Figure 2 This is a schematic diagram of the overall structure of a sodium cyanide reaction vessel according to the present invention.

[0020] Figure 3 This is a schematic diagram of the connection structure between the stirring shaft and the motor of a sodium cyanide reactor according to this utility model.

[0021] Figure 4 This is a schematic diagram of the lid structure of a sodium cyanide reaction vessel according to the present invention.

[0022] 1. Reactor body; 2. Reactor lid; 3. Stirring shaft; 4. Spiral tube; 5. Outer shell; 6. Motor; 101. Discharge port; 201. Manhole; 202. Main feed port; 203. Auxiliary feed port; 204. Catalyst feed port; 205. Pressure gauge port; 301. Middle layer open impeller; 302. Bottom layer anchor impeller; 303. Bottom bearing; 304. Top bearing; 305. Double-end mechanical seal; 401. Inlet pipe; 402. Outlet pipe; 501. Elastic collar; 502. Y-type pipe. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] Please see Figure 1-4A sodium cyanide reaction vessel includes a vessel body 1, a vessel cover 2 above the vessel body 1, and a stirring shaft 3 disposed within the vessel body 1. The stirring shaft 3 is characterized in that its top end penetrates the top flange of the vessel cover 2 and is connected to a motor 6, and is sealed to the vessel body 1 via a double-end mechanical seal 305. The motor 6 is fixed to the top of the vessel cover 2. The stirring shaft 3 has a middle layer of open blades 301 and a bottom layer of anchor blades 302 arranged axially. Bearings are provided at both ends of the stirring shaft 3; the bottom bearing 303 is a radial bearing, a self-lubricating ceramic bearing, and the top bearing 304 is a thrust bearing, a double-direction angular contact ball bearing. The inner wall of the vessel body 1 is 316L stainless steel lined with fluoropolymer, and the base material of the stirring shaft 3 is 316L stainless steel with Stellite alloy overlay welded to its surface. The moving ring of the double-end mechanical seal 305 at the top of the stirring shaft 3 is made of silicon carbide, and the stationary ring is made of graphite, with a surface roughness Ra ≤ 0.8 μm between the moving and stationary rings. After closing all feed flanges, start motor 6. The stirring shaft 3 drives the middle open blade 301 and the bottom anchor blade 302 to operate at a preset speed to ensure that the material is evenly dispersed.

[0025] Please see Figure 1-2 , Figure 4 The vessel body 1 has an outer shell 5 with the same shape as the vessel body 1, and the outer shell 5 is welded to the flange at the top of the vessel body 1. A discharge port 101 is provided through the bottom of the vessel body 1, penetrating the outer shell 5. A spiral tube 4 is provided on the outside of the vessel body 1 and inside the outer shell 5, and the spiral tube 4 surrounds the vessel body 1. The spiral tube 4 has a multi-layer spiral structure. The inlet pipe 401 of the spiral tube 4 is connected to an external refrigerant or heat source, and the outlet pipe 402 of the spiral tube 4 is connected to an external heat exchanger. After the vessel body 1 is connected to the flange of the vessel cover 2, it is radially reinforced and sealed with an elastic ring 501. The vessel cover 2 has a manhole 201, a main feed port 202, an auxiliary feed port 203, and a catalyst feed port 204, all of which are quick-release flange structures. The vessel cover 2 also has a pressure gauge port 205. After confirming good sealing, open the main feed port 202, auxiliary feed port 203, and catalyst feed port 204 on the reactor lid 2, and slowly inject the solvent, medium, and catalyst in sequence, then close all feed flanges. Introduce refrigerant or heat medium through the inlet pipe 401 of the spiral pipe 4, and connect the outlet pipe 402 to an external heat exchanger to form a closed loop. Dynamically adjust the refrigerant or heat medium flow rate to maintain the reaction temperature within ±1℃ of the set value. After the reaction is complete, open the bottom outlet port 101 to discharge the product. After the reactants are collected, inject an alkaline cleaning solution (such as NaOH solution) through the main feed port 202, soak for 30 minutes, and then start stirring for cleaning.

[0026] Please see Figure 1-2The vessel body 1 and the outer shell 5 are also sealed, and the outer shell 5 has a through hole for connecting to the Y-shaped pipe 502. A flow regulating valve is installed at the connection end of the Y-shaped pipe 502 and the outer shell 5, and the other two ends are connected to a nitrogen cylinder and a pressure gauge, respectively. Before using the device, open the Y-shaped pipe 502 on the outer shell 5, and fill it with nitrogen through the flow regulating valve to a pressure of 0.2-0.3 MPa. After closing the nitrogen cylinder valve, observe the pressure change on the pressure gauge to confirm the sealing (stable pressure without drop). Check whether the double-end mechanical seal 305 is installed correctly and whether the elastic ring 501 is pre-tightened and not loose.

[0027] The principle of this utility model: This device forms a physical isolation layer through the tight fit between the moving ring (silicon carbide) and the stationary ring (graphite), coupled with an ultra-low surface roughness (Ra≤0.8μm), effectively preventing the leakage of corrosive sodium cyanide media. The double-end-face design balances the axial pressure difference, adapting to high-pressure conditions. After flange connection, the radial preload of the elastic ring 501 eliminates assembly gaps, forming a secondary sealing barrier to prevent minor leaks caused by vibration or thermal expansion and contraction. The refrigerant or heat medium circulates within the spiral tube 4, exchanging heat efficiently with the vessel body 1 through the tube wall. The multi-layer structure increases the heat exchange path length, and combined with the outer shell 5, achieves a uniform temperature field distribution. Nitrogen gas is continuously introduced into the Y-shaped pipe 502 to create an inert environment, preventing sodium cyanide from oxidizing upon contact with air; during shutdown, pressure is maintained during charging, and pressure changes are monitored in real time by a gauge, triggering an alarm in case of abnormality. The radial stirring of the middle layer open blades 301 and the axial stirring of the bottom layer anchor blades 302 work together to achieve all-round mixing of materials; the open blades enhance the radial turbulence intensity, and the anchor blades remove bottom deposits to ensure reaction uniformity.

[0028] Before using the device, open the Y-shaped pipe 502 on the outer casing 5, and fill it with nitrogen to a pressure of 0.2-0.3 MPa through the flow regulating valve. After closing the nitrogen cylinder valve, observe the pressure change on the gauge to confirm the seal (stable pressure without drop). Check whether the double-end mechanical seal 305 is installed correctly and whether the elastic ring 501 is pre-tightened and not loose. After confirming good sealing, open the main feed port 202, auxiliary feed port 203, and catalyst feed port 204 on the reactor cover 2, and slowly inject the solvent, medium, and catalyst in sequence. Close all feed flanges, start the motor 6, and the stirring shaft 3 will drive the middle layer open blade 301 and the bottom layer anchor blade 302 to run at a preset speed to ensure uniform material dispersion. Introduce refrigerant or heat medium through the inlet pipe 401 of the spiral pipe 4, and connect the outlet pipe 402 to the external heat exchanger to form a closed loop. Dynamically adjust the refrigerant or heat medium flow rate to maintain the reaction temperature within the set value ±1℃ range. Continuously introduce nitrogen gas into the Y-shaped pipe 502 to maintain a slight positive pressure of 0.1-0.2 MPa inside the reactor to prevent air from entering and causing oxidation side reactions.

[0029] After the reaction is complete, open the bottom outlet 101 to discharge the product. After the reactants are collected, inject an alkaline cleaning solution (such as NaOH solution) through the main inlet 202, soak for 30 minutes, and then start stirring for cleaning. Operators must wear gas masks and corrosion-resistant gloves to avoid direct contact with sodium cyanide solution. Eyewash stations and emergency sprinkler systems are provided around the reactor; emergency response plans for leaks are practiced regularly; residual sodium cyanide must be neutralized according to hazardous waste treatment standards and then disposed of by a professional organization.

[0030] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the inventive spirit of the present invention, such designs should fall within the protection scope of the present invention.

Claims

1. A sodium cyanide reaction vessel, comprising a vessel body (1), a vessel cover (2) above the vessel body (1), and a stirring shaft (3) disposed within the vessel body (1), characterized in that: The top of the stirring shaft (3) passes through the top flange of the kettle cover (2) and is connected to the motor (6), and is sealed to the kettle body (1) through a double-end mechanical seal (305). The motor (6) is fixed on the top of the kettle cover (2). The stirring shaft (3) is provided with a middle layer open blade (301) and a bottom layer anchor blade (302) along the axial direction. The outer side of the vessel body (1) has an outer shell (5) with the same shape as the vessel body (1), and the outer shell (5) is welded to the flange at the top of the vessel body (1); the bottom of the vessel body (1) is provided with a discharge port (101), and the discharge port (101) passes through the outer shell (5); a spiral tube (4) is provided on the outer side of the vessel body (1) and inside the outer shell (5), and the spiral tube (4) surrounds the vessel body (1). The spiral tube (4) has a multi-layer spiral structure. The inlet pipe (401) of the spiral tube (4) is connected to an external refrigerant or heat source, and the outlet pipe (402) of the spiral tube (4) is connected to an external heat exchanger. The vessel body (1) and the outer shell (5) are also sealed. The outer shell (5) has a through hole for connecting to the Y-shaped pipe (502). The Y-shaped pipe (502) is connected to the outer shell (5) with a flow regulating valve installed at the connection end. The other two ends are connected to a nitrogen cylinder and a test gauge, respectively.

2. The sodium cyanide reaction vessel according to claim 1, characterized in that: The stirring shaft (3) is equipped with bearings at both ends. The bottom bearing (303) is a radial bearing and a self-lubricating ceramic bearing, while the top bearing (304) is a thrust bearing and a double-direction angular contact ball bearing.

3. The sodium cyanide reaction vessel according to claim 2, characterized in that: The inner wall of the vessel body (1) is made of 316L stainless steel lined with fluorine, and the base material of the stirring shaft (3) is 316L stainless steel with Stellite alloy overlaid on the surface.

4. The sodium cyanide reaction vessel according to claim 3, characterized in that: The dynamic ring of the double-end mechanical seal (305) at the top of the stirring shaft (3) is made of silicon carbide, the stationary ring is made of graphite, and the roughness of the contact end face between the dynamic ring and the stationary ring is Ra≤0.8μm.

5. A sodium cyanide reaction vessel according to claim 3, characterized in that: The vessel body (1) and the vessel cover (2) are connected by a flange and then radially reinforced and sealed by an elastic collar (501).

6. A sodium cyanide reaction vessel according to claim 5, characterized in that: The vessel cover (2) has a manhole (201), a main feed inlet (202), an auxiliary feed inlet (203), and a catalyst feed inlet (204), all of which are flange quick-release structures. The vessel cover (2) is also equipped with a pressure gauge port (205).

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