A method for removing hydrogen chloride from a chloride intermediate

Abstract

The application provides a method for removing hydrogen chloride from a chloride intermediate, and belongs to the technical field of chemical production processes. The chloride intermediate is introduced into a mixer from a material inlet of the mixer, and enters a refining kettle through a two-way channel of the mixer; after the introduction of the chloride intermediate is stopped, refining gas is continuously introduced into the mixer from the material inlet of the mixer for purging, and the chloride is obtained. The method provided by the application can make the material in the refining kettle produce internal circulation by limiting the structure of the mixer, so as to play a role of sufficient stirring and accelerate the removal speed of hydrogen chloride in the chloride intermediate. The results of the examples show that, after the method provided by the application is used for purging for 30 min, the actually measured hydrogen chloride content can reach below 0.05 mg / L, the removal time is greatly reduced, and the annual energy consumption reduction rate can reach 87.5%.

Description

Technical Field

[0001] This invention relates to the field of chemical production process technology, and in particular to a method for removing hydrogen chloride from a chloride intermediate. Background Technology

[0002] The liquid product obtained after the chlorination reaction of fatty acid methyl esters, straight-chain hydrocarbons, or aromatic hydrocarbons is a chloride intermediate, which contains approximately 1% hydrogen chloride gas. The presence of hydrogen chloride gas can affect the quality of the product, therefore it is necessary to remove the hydrogen chloride gas from the chloride intermediate.

[0003] Currently, the common process involves inserting a pipe into the center of the upper part of the chloride intermediate refining reactor and using compressed air or nitrogen for bubbling and purging. However, due to the limited contact between the bubbles and the chloride intermediate, a relatively long bubbling and purging time is required to achieve the required hydrogen chloride content in the chloride intermediate. Furthermore, while this process can achieve the required hydrogen chloride content in the chloride intermediate, it suffers from high energy consumption.

[0004] Therefore, there is an urgent need to provide a method for removing hydrogen chloride from chloride intermediates with high removal efficiency and low energy consumption. Summary of the Invention

[0005] The purpose of this invention is to provide a method for removing hydrogen chloride from chloride intermediates with high removal efficiency and low energy consumption.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for removing hydrogen chloride from a chloride intermediate, comprising the following steps: (1) A mixer is installed at the bottom of the chloride intermediate refining vessel; The mixer includes a conical nozzle, a mixing chamber, and a spiral diffusion nozzle connected sequentially from bottom to top; The conical nozzle comprises a tubular cavity, a conical cavity, and a nozzle that are connected sequentially from bottom to top; the inner diameter of the upper port of the conical cavity is smaller than the inner diameter of the lower port; the lower port of the tubular cavity is the inlet of the mixer; The mixing chamber includes a negative pressure zone, a gas-liquid mixing zone, and a diffusion zone connected sequentially from bottom to top; the inner diameter of the gas-liquid mixing zone is smaller than the inner diameters of the negative pressure zone and the diffusion zone; the cavity wall of the negative pressure zone is provided with multiple bidirectional channels; the bidirectional channels are located below the top of the nozzle; The cone-shaped cavity of the conical nozzle is nested within the negative pressure zone of the mixing chamber; (2) The chloride intermediate is introduced into the mixer through the inlet of the mixer and then into the refining kettle through the bidirectional channel of the mixer; (3) After the chloride intermediate is stopped, the purified gas is continuously introduced into the mixer through the inlet to purge the mixture and obtain chloride.

[0007] Preferably, in step (1), the ratio of the inner diameter of the upper port to the lower port of the cone-shaped cavity is 0.4 to 0.6:1.

[0008] Preferably, the jet angle of the spiral diffusion nozzle in step (1) is 30~120°.

[0009] Preferably, the ratio of the cavity height of the negative pressure zone, the gas-liquid mixing zone and the diffusion zone in step (1) is 1:(0.4~0.6):(0.3~0.5).

[0010] Preferably, the ratio of the inner diameter of the cavity of the negative pressure zone, the gas-liquid mixing zone and the diffusion zone in step (1) is 1:(0.5~0.7):(0.8~0.9).

[0011] Preferably, the number of bidirectional channels in step (1) is 3 to 5.

[0012] Preferably, in step (2), the flow rate of the chloride intermediate entering the mixer through the inlet is 1.5~2m. 3 / h.

[0013] Preferably, the refining gas in step (3) is selected from nitrogen or dry air.

[0014] Preferably, the flow rate of the refining gas in step (3) is 1~3m³. 3 / min.

[0015] Preferably, the purging time in step (3) is 15~30 minutes.

[0016] This invention provides a method for removing hydrogen chloride from a chloride intermediate, comprising the following steps: the chloride intermediate is introduced into the mixer through the inlet of the mixer located at the bottom of the refining vessel, and enters the refining vessel through the bidirectional channel of the mixer; after the introduction of the chloride intermediate is stopped, the refining gas is continuously introduced into the mixer through the inlet of the mixer for purging, thereby obtaining chloride. This invention utilizes a mixer installed at the bottom of the refining vessel. The chloride intermediate enters the refining vessel through a bidirectional channel of the mixer in a gushing motion. The surging liquid generates temperature convection, uniformly mixing the temperature within the refining vessel. During material convection, hydrogen chloride in the chloride intermediate precipitates, forming hydrogen chloride bubbles that exit the liquid phase, accelerating the removal of hydrogen chloride from the chloride intermediate and improving removal efficiency. After the chloride intermediate is introduced, refining gas is continuously introduced into the mixer through its inlet for purging. Both the refining gas and the chloride intermediate enter the mixer through its inlet, avoiding dead zones where materials do not flow and ensuring thorough removal of hydrogen chloride from the chloride intermediate. Furthermore, the refining gas, entering the mixer through its inlet, is then sprayed into the refining vessel through a spiral diffusion nozzle. Because the nozzle has a conical structure and a bidirectional channel... The channel is positioned below the top of the conical nozzle. Due to the Venturi effect, the purified gas creates a negative pressure zone within the mixer. Under pressure, the chloride intermediate is drawn into the mixer through the bidirectional channel. Because the inner diameter of the gas-liquid mixing zone is smaller than that of the negative pressure zone, the turbulence effect is increased, leading to more uniform gas-liquid mixing. As the gas-liquid mixture flows from the mixing zone to the diffusion zone, the larger inner diameter of the diffusion zone further promotes uniform mixing. After being sprayed through the spiral diffusion nozzle, the uniformly mixed gas-liquid mixture is ejected in an umbrella-like shape, forming a film. Hydrogen chloride gas rises from the liquid and is discharged through the top of the refining vessel, reducing the hydrogen chloride content of the chloride in the refining vessel to meet the requirements for the chloride product, thus obtaining chloride that meets product requirements. The method provided by this invention enables internal circulation of materials within the refining vessel, achieving thorough stirring and accelerating the removal of hydrogen chloride from the chloride intermediate. The results of the examples show that after purging for 30 minutes using the method provided by the present invention, the measured hydrogen chloride content can reach below 0.05 mg / L, which greatly reduces the removal time; and the annual energy consumption reduction rate can reach 87.5%. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the mixer provided by the present invention; exist Figure 1 In the diagram: a is the connecting flange; b is the bidirectional channel; c is the spiral diffuser nozzle; d is the mixer inlet; e is the cone-shaped cavity; f is the negative pressure zone; g is the gas-liquid mixing zone; h is the diffusion zone; i is the nozzle. Figure 2This is a schematic diagram of the apparatus for removing hydrogen chloride from the chloride intermediate used in an embodiment of the present invention; exist Figure 2 In the diagram: 1 is the refining gas inlet; 2 is the chlorination intermediate inlet; 3 is the chlorination intermediate calibration port; 4 is the pressure balance pipe; 5 is the hydrogen chloride outlet; 6 is the gas-liquid separator; 7 is the stabilizer inlet; 8 is the chloride finished product packaging port; 9 is the finished product pump; 10 is the refining kettle material inlet; 11 is the mixer (i.e., the hydrogen chloride phase mixing injector at the chlorination intermediate spring inlet); 12 is the chloride intermediate refining kettle; 13 is the refining kettle level gauge; 14 is the sampling and testing port. Detailed Implementation

[0018] This invention provides a method for removing hydrogen chloride from a chloride intermediate, comprising the following steps: (1) A mixer is installed at the bottom of the chloride intermediate refining vessel; The mixer includes a conical nozzle, a mixing chamber, and a spiral diffusion nozzle connected sequentially from bottom to top; The conical nozzle comprises a tubular cavity, a conical cavity, and a nozzle that are connected sequentially from bottom to top; the inner diameter of the upper port of the conical cavity is smaller than the inner diameter of the lower port; the lower port of the tubular cavity is the inlet of the mixer; The mixing chamber includes a negative pressure zone, a gas-liquid mixing zone, and a diffusion zone connected sequentially from bottom to top; the inner diameter of the gas-liquid mixing zone is smaller than the inner diameters of the negative pressure zone and the diffusion zone; the cavity wall of the negative pressure zone is provided with multiple bidirectional channels; the bidirectional channels are located below the top of the nozzle; The cone-shaped cavity of the conical nozzle is nested within the negative pressure zone of the mixing chamber; (2) The chloride intermediate is introduced into the mixer through the inlet of the mixer and then into the refining kettle through the bidirectional channel of the mixer; (3) After the chloride intermediate is stopped, the purified gas is continuously introduced into the mixer through the inlet to purge the mixture and obtain chloride.

[0019] The present invention includes a mixer installed at the bottom of the chloride intermediate refining vessel.

[0020] The present invention does not have any special limitations on the composition of the chloride intermediate refining vessel; a conventional refining vessel can be used.

[0021] A schematic diagram of the mixer provided by this invention is shown below. Figure 1 As shown.

[0022] like Figure 1 As shown, in this invention, the mixer includes a conical nozzle, a mixing chamber, and a spiral diffusion nozzle connected sequentially from bottom to top.

[0023] like Figure 1As shown, in this invention, the conical nozzle includes a tubular cavity, the lower port of which serves as the inlet of the mixer. This invention uses the lower port of the tubular cavity as the inlet of the mixer, through which chloride materials or refined gases enter the mixer. This invention does not impose any special limitations on the inner diameter and height of the tubular cavity; they can be adjusted as needed.

[0024] like Figure 1 As shown, in this invention, the conical nozzle includes a conical cavity communicating above the tubular cavity. In this invention, the inner diameter of the upper port of the conical cavity is smaller than the inner diameter of the lower port. In this invention, the ratio of the inner diameter of the upper port to the inner diameter of the lower port of the conical cavity is preferably 0.4~0.6:1, more preferably 0.4~0.5:1. In this invention, when the ratio of the inner diameter of the upper port to the inner diameter of the conical cavity is within the above range, the rate at which material or refined gas entering from the inlet is ejected at the nozzle can be significantly increased. This invention does not have a particular limitation on the specific value of the inner diameter of the upper port and the lower port of the conical cavity, as long as the above ratio is satisfied.

[0025] like Figure 1 As shown, in this invention, the conical nozzle includes an orifice communicating above the conical cavity. In this invention, the inner diameter of the orifice is preferably the same as the diameter of the upper port of the conical cavity. This invention uses the orifice to inject material or refined gas introduced from the mixer inlet into the mixer.

[0026] like Figure 1 As shown, in this invention, the mixer includes a mixing chamber communicating with a conical nozzle.

[0027] like Figure 1 As shown, in this invention, the mixing chamber includes a negative pressure zone. In this invention, the conical cavity of the conical nozzle is nested within the negative pressure zone of the mixing chamber.

[0028] like Figure 1 As shown, in this invention, the cavity wall of the negative pressure zone is provided with multiple bidirectional channels; the bidirectional channels are positioned below the top of the nozzle. This invention, by providing multiple bidirectional channels in the cavity wall of the negative pressure zone, enables the chloride intermediate to be drawn back into the negative pressure zone under negative pressure. In this invention, the number of bidirectional channels is preferably 3 to 5, more preferably 4 to 5. By employing multiple bidirectional channels, this invention, on the one hand, promotes the chloride intermediate to form a multi-channel gushing flow, entering the chloride intermediate refining reactor. The surging liquid generates temperature convection, uniformly stirring the temperature inside the reactor. During material convection, hydrogen chloride in the chloride intermediate precipitates, forming hydrogen chloride bubbles that exit the liquid phase, accelerating the removal of hydrogen chloride from the chloride intermediate; on the other hand, it also enables the chloride intermediate to be drawn back into the negative pressure zone under negative pressure after the introduction of refining gas.

[0029] like Figure 1 As shown, in this invention, the mixing chamber includes a gas-liquid mixing zone connected above the negative pressure zone.

[0030] like Figure 1 As shown, in this invention, the mixing chamber includes a diffusion zone communicating with the gas-liquid mixing zone above it.

[0031] like Figure 1 As shown, in this invention, the preferred ratio of the cavity heights of the negative pressure zone, the gas-liquid mixing zone, and the diffusion zone is 1:(0.4~0.6):(0.3~0.5), more preferably 1:(0.4~0.5):(0.4~0.5). This invention does not impose any specific limitations on the specific values ​​of the cavity heights of the negative pressure zone, the gas-liquid mixing zone, and the diffusion zone; adjustments can be made as needed to ensure that the ratio of the cavity heights of each region is within the aforementioned range.

[0032] like Figure 1 As shown, in this invention, the ratio of the inner diameters of the cavities in the negative pressure zone, the gas-liquid mixing zone, and the diffusion zone is preferably 1:(0.5~0.7):(0.8~0.9), more preferably 1:(0.5~0.6):(0.8~0.9). This invention does not impose any specific limitations on the individual values ​​of the inner diameters of the cavities in the negative pressure zone, the gas-liquid mixing zone, and the diffusion zone; adjustments can be made as needed to ensure that the ratio of the inner diameters of each region falls within the aforementioned range.

[0033] like Figure 1 As shown, in this invention, the mixing chamber includes a spiral diffusion nozzle communicating with the upper part of the diffusion zone. This invention enables the gas-liquid mixture to be ejected in an inverted umbrella-like manner via the spiral diffusion nozzle. The ejected gas-liquid mixture forms a film, with the mixed hydrogen chloride gas rising from the liquid and separating from the chloride intermediate. In this invention, the jet angle of the spiral diffusion nozzle is preferably 30~120°, more preferably 30°, 60°, or 120°.

[0034] After installing a mixer at the bottom of the chloride intermediate refining vessel, the present invention introduces the chloride intermediate into the mixer through the inlet of the mixer, and then into the refining vessel through the bidirectional channel of the mixer.

[0035] This invention does not specifically limit the type of chloride intermediate; conventional chloride intermediates can be used. In this invention, the chloride intermediate is preferably a chloride intermediate obtained after the chlorination reaction of fatty acid methyl esters, straight-chain hydrocarbons, or aromatic hydrocarbons. The volume content of hydrogen chloride in the chloride intermediate is preferably 0.5-5%, more preferably 1%.

[0036] This invention does not impose any particular limitation on the flow rate of the chloride intermediate introduced into the mixer; it can be adjusted according to conventional methods. In this invention, the preferred flow rate of the chloride intermediate introduced into the mixer via the mixer inlet is 1.5~2 m³ / h. 3 / h, more preferably 1.5m 3 / h.

[0037] This invention does not specifically limit the method for controlling the pressure inside the refining vessel; conventional methods for controlling reactor pressure are sufficient. In this invention, the preferred method for controlling the pressure inside the refining vessel is to install a pressure balancing pipe at the top of the refining vessel. In this invention, the chloride intermediate enters the chloride intermediate refining vessel through a mixer in a multi-channel gushing manner, agitating the gas precipitated in the liquid. This invention utilizes a pressure balancing pipe to balance the gas pressure inside the refining vessel and uses the pressure balancing pipe to return the precipitated hydrogen chloride gas to the chlorination reactor.

[0038] Preferably, the chloride intermediate is stopped after its volume reaches 80% of the volume of the refining vessel.

[0039] In this invention, after the chloride intermediate is stopped, a purging gas is continuously introduced into the mixer through the mixer inlet to purge the mixture and obtain chloride.

[0040] In this invention, the purified gas is preferably nitrogen or dry air. The dry air is preferably dry air with a dew point of -70°C. Using the above-mentioned purified gas to purge the chloride intermediate is more beneficial for removing hydrogen chloride gas. This invention does not have any particular limitation on the apparatus for generating the purified gas; a conventional gas source device is sufficient. In this invention, the apparatus for generating the purified gas is preferably a gas compressor, with a power preferably of 50-60 kW / h, more preferably 55 kW / h; and a gas production capacity preferably of 10-15 m³ / h. 3 / h, more preferably 10m 3 / h.

[0041] In this invention, the flow rate of the refining gas is preferably 1~3 m³ / h. 3 / min, more preferably 1.5~2.5m 3 / min. In this invention, the purging time is preferably 15-30 min, more preferably 30 min. By controlling the flow rate of the refining gas within the above range, this invention facilitates the formation of negative pressure in the mixer, causing the chloride intermediate liquid to be drawn back into the mixer, and ensuring sufficient removal of hydrogen chloride from the chloride intermediate during the above purging time.

[0042] Preferably, this invention includes a discharge pipe and a gas-liquid separator at the top of the refining vessel. The invention discharges hydrogen chloride gas from the refining vessel through the discharge pipe and removes entrained liquid using the gas-liquid separator, thus obtaining hydrogen chloride gas.

[0043] Preferably, the hydrogen chloride treated by the gas-liquid separator is fed into a hydrogen chloride absorption system for recovery. The present invention does not impose any particular limitation on the hydrogen chloride absorption system; conventional absorption devices are sufficient.

[0044] This invention incorporates a mixer at the bottom of the refining vessel, which promotes internal circulation of the material within the refining vessel for chloride intermediates, thereby achieving thorough stirring and accelerating the removal of hydrogen chloride from the chloride intermediates. Consequently, it can fully remove hydrogen chloride from the chloride intermediates in a shorter purging time, solving the problem of long purging times in the prior art for removing hydrogen chloride from chloride intermediates. This improves removal efficiency and reduces energy consumption.

[0045] In one embodiment of the present invention, the apparatus for removing hydrogen chloride from the chloride intermediate is preferably as follows: Figure 2 As shown.

[0046] exist Figure 2 In the diagram, 1 is the refining gas inlet; 2 is the chlorination intermediate inlet; 3 is the chlorination intermediate calibration port; 4 is the pressure balance pipe; 5 is the hydrogen chloride outlet; 6 is the gas-liquid separator; 7 is the stabilizer inlet; 8 is the chloride finished product packaging port; 9 is the finished product pump; 10 is the refining kettle material inlet; 11 is the mixer; 12 is the chloride intermediate refining kettle; 13 is the refining kettle level gauge; and 14 is the sampling and testing port.

[0047] In one embodiment of the present invention, the method for removing hydrogen chloride from the chloride intermediate preferably includes: continuously introducing the chloride intermediate into the refining reactor quality calibrator 3 through the chloride intermediate refining reactor inlet 2 to complete online quality calibration; continuously introducing the chloride intermediate into the chloride intermediate refining reactor through the upper outlet of the quality calibrator and the intermediate refining reactor level gauge pipe 13; entering the chloride intermediate refining reactor through the bottom inlet 10 of the chloride intermediate refining reactor via the mixer 11 to form a multi-channel gushing flow; and returning the gas precipitated in the gushing liquid to the chlorination reactor through the pressure balance pipe 4 to achieve pressure balance; and closing the chloride intermediate inlet when the material continuously entering the chloride intermediate refining reactor reaches 80% of the reactor volume. 2. Stop feeding through the pipeline valve and close the valve of the gas pressure balance pipeline 4; quantitatively open the valve of the refining gas pipeline 1 to guide the refining gas from the mixer 11 into the intermediate refining kettle 12. The refining gas is sprayed from the mixer 11 into the intermediate refining kettle 12. At the same time, the liquid material in the intermediate refining kettle 12 flows back to the suction mixer. The liquid and gas are fully mixed in the mixer 11. During the mixing process, saturated hydrogen chloride gas in the liquid material is released and mixed with the compressed gas. At the same time, the liquid and gas mixture sprayed from the mixer 11 forms a film state. The mixed hydrogen chloride gas floats from the liquid and passes through the hydrogen chloride discharge pipeline 5 in the middle of the intermediate refining kettle 12. After passing through the gas-liquid separator 6 to remove the entrained liquid, it enters the hydrogen chloride absorption system. After the chloride product is qualified, add 3‰ stabilizer through the pipeline 7 and continue blowing for 5 minutes to mix it evenly; open the material inlet 10 of the refining kettle and use the finished product pump 9 to package the finished product through the finished product pipeline 8.

[0048] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0049] Example 1

[0050] A method for removing hydrogen chloride from a chloride intermediate, comprising the following steps: (1) A mixer is installed at the bottom of the chloride intermediate refining vessel; The structural diagram of the mixer provided in this embodiment is as follows: Figure 1 As shown: like Figure 1 As shown, the mixer consists of a connected conical nozzle, a mixing chamber, and a spiral diffusion nozzle, arranged from bottom to top. The conical nozzle consists of, from bottom to top, a connected tubular cavity, a conical cavity, and a nozzle; the inner diameter of the upper port of the conical cavity is smaller than the inner diameter of the lower port; the lower port of the tubular cavity is the inlet of the mixer; the ratio of the inner diameter of the upper port to the lower port of the conical cavity is 0.5:1. The mixing chamber consists of a connected negative pressure zone, a gas-liquid mixing zone, and a diffusion zone from bottom to top; the inner diameter of the gas-liquid mixing zone is smaller than the inner diameters of the negative pressure zone and the diffusion zone; the cavity wall of the negative pressure zone is provided with 5 bidirectional channels; the bidirectional channels are located below the top of the nozzle; The cone-shaped cavity of the conical nozzle is nested within the negative pressure zone of the mixing chamber; The jet angle of the spiral diffuser nozzle is 30°.

[0051] (2) The chloride intermediate (hydrogen chloride volume content of 1%) is introduced into the mixer through the inlet of the mixer, and then into the refining kettle through the bidirectional channel of the mixer, specifically: like Figure 2 As shown: Chloride intermediates are continuously fed into the refining reactor's quality calibrator through the inlet of the refining reactor to complete online quality calibration. The chloride intermediates then continuously enter the refining reactor through the liquid level pipe at the top outlet of the quality calibrator. At the bottom inlet of the refining reactor, the mixture, through a mixer, splits into five inlets to form a multi-channel gushing flow, entering the refining reactor. Gas precipitated from the gushing liquid returns to the chlorination reactor through the pressure balance pipe, achieving pressure balance. When the material continuously entering the refining reactor reaches 80% of the reactor volume, the inlet valve of the chloride intermediate pipe is closed to stop feeding, and the pressure balance pipe valve is also closed. (3) After the chloride intermediate is stopped, use 10m 3 A gas compressor (55 kW / h) provides purified gas, which is then discharged at a rate of 1.5 m³ / h. 3A flow rate of / min is continuously introduced into the mixer through the inlet for 30 minutes to purge the chloride to achieve a hydrogen chloride volume content of 0.05mg / L, thus obtaining chloride. Specifically, the valve of the refining gas pipeline is quantitatively opened to guide the refining gas from the nozzle of the mixer into the intermediate refining vessel. The refining gas is injected into the intermediate refining vessel from the central spiral injector of the mixer at a fixed angle in an inverted umbrella state. At the same time, a negative pressure is generated in the negative pressure zone of the mixer, causing the liquid material in the intermediate refining vessel to flow back from the bidirectional channel of the mixer to the negative pressure zone of the mixer. The liquid and gas are fully mixed in the negative pressure zone of the mixer. During the mixing process, saturated hydrogen chloride gas in the liquid material is released and mixed with the compressed gas. At the same time, it is ejected from the central spiral injector of the mixer at a fixed angle in an inverted umbrella state. The ejected liquid and gas mixture forms a film state. The mixed hydrogen chloride gas floats from the liquid and passes through the hydrogen chloride discharge pipe in the middle of the intermediate refining vessel. After passing through the gas-liquid separator to remove the entrained liquid, hydrogen chloride is obtained and enters the hydrogen chloride absorption system. After the chloride product is qualified, add 3‰ stabilizer (FHW-1 high-efficiency composite stabilizer) through the pipeline, continue blowing air for 5 minutes to mix it evenly, open the material inlet of the refining kettle and use the finished product pump to package the finished product through the finished product pipeline.

[0052] Comparative Example 1

[0053] A method for removing hydrogen chloride from a chloride intermediate: A chloride intermediate (hydrogen chloride volume content of 1%) is introduced into the refining reactor until the volume of the chloride intermediate occupies 80% of the volume of the refining reactor, at which point the introduction of the chloride intermediate is stopped. Using 10m 3 A gas compressor (power 55kw / h) provides purified gas. A pipe is inserted into the top of the purification vessel, and the purified gas is used for bubbling and purging. After purging for 4 hours, the hydrogen chloride content in the chloride in the purification vessel is detected to be 0.05mg / L, and the supply of purified gas is stopped.

[0054] The experimental results show that the method provided by this invention can reduce the hydrogen chloride content in the chloride intermediate to 0.05 mg / L in 30 minutes, while the method provided in the comparative example requires 4 hours to achieve the same effect. Calculations show that the energy consumption per ton of product for the method provided in the comparative example is 31.4 kWh, which translates to an annual energy consumption of 1.57 million kWh for a 50 kt / a production facility. In contrast, the method provided by this invention reduces the energy consumption per ton of product to 3.9 kWh, resulting in an annual energy consumption of 195,000 kWh for a 50 kt / a production facility. This represents a significant energy reduction of 1.375 million kWh, or 87.5%. Therefore, the method provided by this invention can significantly shorten the purging time and reduce energy consumption when the hydrogen chloride content in the chloride intermediate reaches the required value.

[0055] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for removing hydrogen chloride from a chloride intermediate, comprising the following steps: (1) A mixer is installed at the bottom of the chloride intermediate refining vessel; The mixer includes a conical nozzle, a mixing chamber, and a spiral diffusion nozzle connected sequentially from bottom to top; The conical nozzle comprises a tubular cavity, a conical cavity, and a nozzle that are connected sequentially from bottom to top; the inner diameter of the upper port of the conical cavity is smaller than the inner diameter of the lower port; the lower port of the tubular cavity is the inlet of the mixer; The mixing chamber includes a negative pressure zone, a gas-liquid mixing zone, and a diffusion zone connected sequentially from bottom to top; the inner diameter of the gas-liquid mixing zone is smaller than the inner diameters of the negative pressure zone and the diffusion zone; the cavity wall of the negative pressure zone is provided with multiple bidirectional channels; the bidirectional channels are located below the top of the nozzle; The conical cavity of the conical nozzle is nested within the negative pressure zone of the mixing chamber; (2) The chloride intermediate is introduced into the mixer through the inlet of the mixer and then into the refining kettle through the bidirectional channel of the mixer; the chloride intermediate is a liquid; (3) After the chloride intermediate is stopped, the purified gas is continuously introduced into the mixer through the inlet to purge the mixer and obtain the chloride intermediate that has been dehydrochlorinated; The purified gas in step (3) is selected from nitrogen or dry air.

2. The method for removing hydrogen chloride from a chloride intermediate according to claim 1, characterized in that, In step (1), the ratio of the inner diameter of the upper port to the lower port of the conical cavity is 0.4~0.6:

1.

3. The method for removing hydrogen chloride from a chloride intermediate according to claim 1, characterized in that, In step (1), the jet angle of the spiral diffusion nozzle is 30~120°.

4. The method for removing hydrogen chloride from a chloride intermediate according to claim 1, characterized in that, In step (1), the ratio of the cavity heights of the negative pressure zone, the gas-liquid mixing zone, and the diffusion zone is 1:(0.4~0.6):(0.3~0.5).

5. The method for removing hydrogen chloride from a chloride intermediate according to claim 1, characterized in that, In step (1), the ratio of the inner diameter of the cavity of the negative pressure zone, the gas-liquid mixing zone and the diffusion zone is 1:(0.5~0.7):(0.8~0.9).

6. The method for removing hydrogen chloride from a chloride intermediate according to claim 1, characterized in that, The number of bidirectional channels in step (1) is 3 to 5.

7. The method for removing hydrogen chloride from a chloride intermediate according to claim 1, characterized in that, In step (2), the flow rate of the chloride intermediate entering the mixer through the inlet is 1.5~2m. 3 / h.

8. The method for removing hydrogen chloride from a chloride intermediate according to claim 1, characterized in that, The flow rate of the refining gas in step (3) is 1~3m. 3 / min.

9. The method for removing hydrogen chloride from a chloride intermediate according to claim 8, characterized in that, The purging time in step (3) is 15~30 minutes.

Images