CN212166569U - Phosphorus trichloride rectification purification device - Google Patents
Phosphorus trichloride rectification purification device Download PDFInfo
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- CN212166569U CN212166569U CN202020184088.8U CN202020184088U CN212166569U CN 212166569 U CN212166569 U CN 212166569U CN 202020184088 U CN202020184088 U CN 202020184088U CN 212166569 U CN212166569 U CN 212166569U
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Abstract
The utility model belongs to high-purity material purification device field specifically is a rectification purification device of phosphorus trichloride. The device comprises a rectifying kettle, a rectifying column head, a heating and heat-preserving device, a temperature monitoring and adjusting device, a cooling reflux fractionating unit and a liquid level control unit; the rectifying still is provided with a feed inlet, a raffinate discharge port, a still temperature monitoring port and a safety pressure relief port, the heating and heat-insulating device is used for heating a resistance heating pipe and a resistance wire, the temperature monitoring and adjusting device comprises thermocouple remote transmission temperature monitoring and heating power output DCS interlocking automatic control, and the liquid level control and cooling reflux fractionating unit comprises a field and remote transmission liquid level meter for monitoring. This rectification purification device can fully get rid of the trace impurity in the phosphorus trichloride when the phosphorus trichloride of purification, obtains the phosphorus trichloride of high-purity more than 6N, and the temperature monitoring is adjusted and is realized the chain automatically regulated of DCS and make the reaction even and controllable simultaneously, increases the security and simplifies the operation of rectification phosphorus trichloride.
Description
Technical Field
The utility model belongs to high-purity material purification device field specifically is a phosphorus trichloride rectification purification device, and the device can be used to the production of 99.999% and 99.9999% high-purity phosphorus.
Background
Chemical element No. 15, symbol P. In the third period, group VA of the periodic Table of the elements.
Elemental phosphorus has several allotropes. Wherein the white phosphorus or yellow phosphorus is colorless or yellowish transparent crystalline solid. The density was 1.82 g/cc. Melting point 44.1 deg.C, boiling point 280 deg.C, and ignition point 40 deg.C. The phosphor light is emitted when the lamp is placed in the dark. Has bad smell. It is extremely toxic. White phosphorus is practically insoluble in water and readily soluble in carbon disulfide solvent and becomes black phosphorus with a density of 2.70 g/cc and is slightly metallic when heated at high pressure. The ionization energy was 10.486 electron volts. Generally insoluble in common solvents. White phosphorus can be converted to red phosphorus by standing or heating in the absence of air at 250 ℃ for several hours or by exposure to light. Red phosphorus is a reddish brown powder, non-toxic, having a density of 2.34 g/cc, a melting point of 59 deg.C (at 43atm, 590 deg.C, sublimation temperature of 416 deg.C), a boiling point of 200 deg.C, and an ignition point of 240 deg.C. Is insoluble in water.
The high-purity phosphorus is mainly used for preparing III-V group compound semiconductors, high-purity alloys and germanium and silicon single crystal dopants. The semiconductor is the basis of the integrated circuit, because the basis of the integrated circuit is the transistor, the transistor is invented to create the integrated circuit, and the basis of the transistor is the semiconductor. The semiconductor material can be used for manufacturing large-scale integrated circuits, power devices, photoelectric devices, pressure sensors, thermoelectric refrigeration and other purposes; the micro-electro-mechanical system (MEMS) can be prepared by utilizing the micro-machining technology of micro-electronics, and can be applied to the fields of electronics and medical treatment.
With the development degree of the semiconductor industry becoming higher and higher, the quality requirement for semiconductor raw materials is also increasing. At present, a great part of high-purity and even ultra-high-purity semiconductor materials required by the domestic semiconductor industry, particularly electronic products and photovoltaic products, are imported, and the domestic production technology of the high-purity materials cannot reach or realize industrial large-scale production, so that the domestic market demand cannot be met. Therefore, the high-purity phosphorus has a very prominent position in the electronic industry, and the market demand is short. How to produce high-purity phosphorus safely and efficiently is urgent.
There are many methods for producing high-purity phosphorus, including oxidation, distillation, zone melting, electromagnetic purification, and the like. However, these methods are all applicable to small-scale production, and have unstable quality and a production purity of not higher than 5N. The most mature and stable method is to carry out acid washing, chlorination, rectification and reduction on industrial-grade yellow phosphorus to obtain high-purity yellow phosphorus with the purity of more than 6N, and phosphorus trichloride obtained after chlorination of the yellow phosphorus needs to further remove residual trace impurities such As Cu, Pb, Fe, Ni, As, Se, S and the like, so that the phosphorus trichloride with the purity of more than 6N is used As a raw material to enter a reduction system. The existing rectification system is made of a quartz kettle, the heating mode is the traditional electric furnace plate heating mode, and the temperature and liquid level control is field manual control. There are mainly the following problems:
1. the production efficiency is low: only about 10 liters of phosphorus trichloride can be added into a single kettle for one-time feeding, the production period of the single kettle is short, the start and stop of equipment are too frequent, and the ineffective working time is too long.
2. The safety is low: although the quartz material has high purity and is corrosion resistant, the quartz material is fragile. The potential danger of crushing exists in the rectification process of phosphorus trichloride, and the column head cooling water jacket is crushed and leaked to cause cooling water to flow into a kettle body to react with the phosphorus trichloride violently to cause explosion.
3. The production stability is poor: the manual control on site is more, so that more uncertain factors are caused, the production fluctuation is large, and the product quality is influenced.
4. Large loss and high cost: the traditional electric stove plate is used for heating, so that the heat loss is large, and the production cost is increased. The residual liquid of phosphorus trichloride is discharged frequently, and the indirect loss of phosphorus trichloride is improved.
Disclosure of Invention
The invention provides a phosphorus trichloride rectification purification device, aiming at solving the problems of the existing phosphorus trichloride rectification purification equipment. The device can effectively solve the technical problems of low production efficiency, low safety, poor production stability, high loss and the like of the existing phosphorus trichloride purification system.
In order to realize the purpose of the invention, the technical scheme of the utility model is as follows:
a rectification purification device of phosphorus trichloride comprises a rectification kettle, a rectification column and a rectification column head, wherein the rectification column is vertically arranged on the rectification kettle, the rectification column head is arranged on the rectification column, and the rectification kettle, the rectification column and the rectification column head are connected with each other through flanges.
A resistance heating device is arranged in the rectifying still, a quartz ring packing area is arranged in the rectifying column, a heat-insulating layer is wrapped outside the rectifying column, and a cooling reflux fractionating device is arranged in the column head of the rectifying column. The cooling reflux fractionating device is respectively provided with a cooling water outlet, a cooling water inlet, a tail gas discharge port and a product distillation outlet; the cooling water outlet, the cooling water inlet and the tail gas discharge port are all arranged at the top of the cooling reflux fractionating device, the bottom end of the cooling reflux fractionating device is of a V-shaped structure, and the product distillation outlet is arranged at the bottom end of the cooling reflux fractionating device. Phosphorus trichloride is heated to a boiling point through a resistance heating device in a rectifying still kettle to generate phosphorus trichloride steam, impurities in the phosphorus trichloride steam are removed through a quartz ring packing area of a rectifying column, and the phosphorus trichloride steam after the impurities are removed is partially used as a product to be fractionated and stored after being cooled through a column head of the rectifying column.
A liquid level monitoring device is arranged on the transverse side surface of the rectifying still; a feed inlet, a safe pressure relief opening, a phosphorus trichloride steam outlet and a kettle temperature monitoring opening are arranged at the upper end of the rectifying kettle; and a residual liquid discharge port is arranged at the bottom of the rectifying kettle. The residual liquid discharge port and the feed port are connected with a ball valve and manually controlled by the ball valve, and the phosphorus trichloride steam discharge port is connected with a rectification column through a flange.
The resistance heating device is arranged in the rectifying still and close to the lower side, the heating device is of a tubular resistance structure, a thermocouple is arranged on the equipment, and the thermocouple and the resistance wire are connected with a temperature controller through a main power switch.
The heat-insulating layer of the rectifying column is heated by circumferentially winding a resistance wire, a temperature measuring hole of a column head of the rectifying column is arranged on the column head of the rectifying column, a thermocouple is arranged in the temperature measuring hole of the column head of the rectifying column, and the thermocouple and the resistance wire are connected to a temperature controller through a main power switch.
The rectifying kettle, the rectifying column and the column head of the rectifying column are all made of stainless steel materials, quartz ring packing is filled in the packing area, and asbestos heat-insulating materials are wrapped outside the kettle body and the rectifying column. A cooling water jacket structure is arranged in the cooling reflux device; the cooling reflux fractionating device is respectively connected with the thermocouple temperature monitoring device and the DCS interlocking automatic control device, temperature monitoring is carried out through the thermocouple, and automatic heating and heat preservation of the equipment are realized through the DCS interlocking control of the resistance heating output power.
Compared with the prior art, the beneficial effects of the utility model are that:
the rectifying kettle is made of special stainless steel materials, can be properly amplified in size design, improves the single-kettle feeding amount by about 4 times before, greatly improves the single-kettle feeding amount, reduces the frequency of starting and stopping the furnace, reduces the non-effective working time, and further improves the production efficiency.
(II) the utility model discloses phosphorus trichloride rectification purification device is changed special stainless steel material into by the quartz material with rectifying still, rectifying column and rectifying column cap material, has increased equipment intensity, has guaranteed production safety.
And (III) a thermocouple is adopted for temperature monitoring and is interlocked with resistance heating output power DCS to realize automatic heating of the equipment, so that the reaction is uniform and controllable, and the production stability is improved.
And (IV) the resistance heating device is adopted to heat the inner part of the kettle body and insulate the outer part of the kettle body, so that the electric heat utilization efficiency is improved, the heat loss is reduced, and the loss and the production cost are reduced.
Drawings
FIG. 1 is a schematic structural diagram of a rectification and purification device of phosphorus trichloride.
Reference numerals: 1-a rectifying still, 2-a rectifying column, 3-a rectifying column head, 4-a safety pressure relief port, 5-a charging port, 6-a liquid level monitoring device, 7-a raffinate discharge port, 8-a resistance heating device, 9-a phosphorus trichloride steam discharge port, 10-a quartz ring packing area, 11-a rectifying column heat insulation layer, 12-a cooling reflux fractionating device, 13-a cooling water outlet, 14-a cooling water inlet, 15-a tail gas discharge port, 16-a product distillation outlet, 17-a phosphorus trichloride raw material filling area, 18-a rectifying column head temperature measuring hole, 19-a kettle temperature monitoring port and 20-a flange joint.
Fig. 2 is a side view of the rectifying still in the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
As shown in figure 1, the rectification and purification device for phosphorus trichloride comprises a rectification kettle 1, a rectification column 2 and a rectification column head 3, wherein the rectification column 2 is vertically arranged on the rectification kettle 1, the rectification column head 3 is arranged on the rectification column 2, and the rectification kettle 1, the rectification column 2 and the rectification column head 3 are connected through flanges. The rectifying still 1 is a container for containing a phosphorus trichloride raw material and is also a device for heating to generate phosphorus trichloride steam, and the rectifying still 1 is provided with a residual liquid discharge port 7, a resistance heating device 8, a feed port 5, a safety pressure relief port 4 and a liquid level monitoring device 6; the phosphorus trichloride raw material 17 in the rectifying still 1 is heated to a boiling point mainly by a resistance heating device 8, the generated phosphorus trichloride steam is filtered by a rectifying column 2 to remove impurities, and finally, the phosphorus trichloride product is distilled by cooling and fractionating through a rectifying column head 3.
Specifically, a feed inlet 5 is arranged on the rectifying still 1, the raw material of phosphorus trichloride is added into the rectifying still 1 to a specified liquid level by opening a ball valve of the feed inlet 5, phosphorus trichloride raw material in the rectifying still 1 is heated to boiling point by a resistance heating device 8 to generate phosphorus trichloride steam, the phosphorus trichloride steam enters the rectifying column 2 through a steam discharge port 9, when the phosphorus trichloride steam passes through quartz ring packing in the rectifying column 2, the phosphorus trichloride steam and the condensed reflux phosphorus trichloride liquid exchange heat on the surface of the quartz ring and remove impurities in the raw materials, the phosphorus trichloride steam after the impurities are removed rises to enter a rectification column head 3, the phosphorus trichloride steam is cooled into a liquid state by a cooling reflux fractionation device 12, finally, a small part of the phosphorus trichloride liquid is fractionated to a product storage device through a product distillation outlet 16, and the rest of the phosphorus trichloride liquid is returned to the rectification kettle 1 as reflux liquid.
Temperature monitoring and automatic control: the temperature of the rectifying still and the column head of the rectifying column is monitored by thermocouples arranged in the temperature measuring holes (2 or a plurality of temperature measuring holes are arranged according to actual conditions) of the temperature monitoring port 19 and the column head of the rectifying column, results are transmitted into the temperature controller, a resistance heating main power supply is controlled by the temperature controller, when the temperature is lower than a set temperature, the power supply is switched on, the resistance heating is heated, when the temperature is higher than the set temperature, the power supply is switched off, the heating is stopped, the phosphorus trichloride steam can reach the rectifying column head 3 to cool and reflux fractionating device 12, meanwhile, the steam quantity cannot be too large, the steam is prevented from overflowing from the tail gas hole 15, and the automatic control of temperature control heating chain is realized. The person skilled in the art can also adjust the heating system and the control thereof according to the specific use requirements, as long as the heating and heat preservation functions of each component can be realized.
Furthermore, the rectification column heat-insulating layer 11 is heated and insulated by winding the resistance wire on the surface of the rectification column in the circumferential direction and wrapping the asbestos heat-insulating material on the outer side of the rectification column, so that phosphorus trichloride steam can reach the column head of the rectification column.
Further, the rectification column head cools the reflux fractionating device 12, normal temperature cooling water enters the jacket from the water inlet 14, flows out from the water outlet 13 from bottom to top after absorbing heat, so that phosphorus trichloride steam near the reflux fractionating device 12 is cooled into liquid on the surface of the reflux fractionating device 12, and the phosphorus trichloride liquid flows into the phosphorus trichloride product distillation outlet 16 along the tip of the reflux fractionating device 12 under the action of gravity and enters the product storage tank for standby.
Further, a residual liquid discharge port 7 is arranged at the bottom of the rectifying still 1, a heating and heat-insulating device of the rectifying system needs to be stopped when the phosphorus trichloride raw material is remained to a specified liquid level, after the temperature of residual liquid in the rectifying still 1 is reduced to room temperature, a ball valve of the residual liquid discharge port 7 is opened to discharge the residual liquid to a specified treatment facility, and the ball valve is closed after the discharge is finished. And opening a ball valve of a feed inlet 5 arranged at the upper side of the rectifying still 1, adding new phosphorus trichloride raw material into the rectifying still 1 again, closing the ball valve of the feed inlet 5 after the phosphorus trichloride raw material is added to a specified liquid level, and opening a heating and heat-insulating system of the rectifying system again for production.
The utility model discloses phosphorus trichloride rectification purification device's concrete working process as follows:
starting a control power supply main switch, starting a heating device 8 of a rectifying still 1 and a heating and heat-insulating device 11 of a rectifying column 2, starting ball valves of a cooling water inlet 14 and a cooling water outlet 13 of a cooling reflux fractionating device 12 in a rectifying column head 3, closing a ball valve of a product distillation outlet 16, starting a system to enter a constant state after the temperature of a phosphorus trichloride raw material 17 in the rectifying still 1 and the temperature of the rectifying column head 3 reach set temperatures, opening the ball valve of the product distillation outlet 16 to fractionate a product to a product storage tank after the constant time reaches a set time, closing the ball valve of the product distillation outlet 16 when the temperature of the phosphorus trichloride raw material 17 in the rectifying still 1 reaches a set liquid level lower limit, closing the heating device 8 of the rectifying still 1 and a power supply of the rectifying column heat-insulating device 11 to stop heating, opening the ball valve of a residual liquid discharge outlet 7 after the temperature of the residual liquid is reduced to a set treatment facility, and closing the ball valve of the residual liquid discharge port 7 after the residual liquid is discharged, opening the ball valve of the feed port 5, adding the phosphorus trichloride raw material into the rectifying still 1 again to a specified liquid level, and closing the ball valve of the feed port 5, thus finishing the production process.
Example 1:
starting a control power supply main switch, starting a rectifying still 1 heating device 8 and a rectifying column 2 heating and heat-insulating device 11, setting a still temperature monitoring port 19 at 80 ℃, setting the temperature measured by a rectifying column head temperature measuring port 18 at 40 ℃ and 70 ℃, starting timing after the temperature reaches the set temperature and is constant, and opening a product fractionating port 16 ball valve to fractionate the product at the speed of 600-800ml (300-400 ml in the original system) per hour after the temperature is constant for 2 hours. When the liquid level of the phosphorus trichloride raw material 17 in the rectifying still is reduced to a specified liquid level, closing a ball valve of a product distillation outlet 16, closing heating and heat-insulating power supplies of the rectifying still 1 and the rectifying column 2, opening a ball valve of a residual liquid discharge port 7 after the temperature in the rectifying still is reduced to room temperature, discharging residual liquid to a specified treatment facility, losing about 10 percent of the residual liquid (30 percent of an original system), closing the ball valve of the residual liquid discharge port 7 after the discharge is finished, opening a ball valve of a feed inlet 5, adding about 50 liters of phosphorus trichloride raw material (10 liters of the original system) into the rectifying still 1 to the specified liquid level, closing the ball valve of the feed inlet 5, and.
This example well system production rate has promoted one time for 600 per hour plus 800ml than former system, and single cauldron capacity about 50 liters has promoted 4 times than former system, and raffinate loss about 10% has reduced 2 times than originally, adopts the utility model discloses the rectifying still has greatly improved production efficiency, has reduced manufacturing cost, lays solid foundation for the production of follow-up 6N level high-purity phosphorus to the comprehensive cost that has reduced 6N high-purity phosphorus has improved market competition.
The above description is only exemplary of the present invention and should not be taken as limiting the scope of the present invention, as any modifications, equivalents, improvements and the like made within the spirit and principles of the present invention are intended to be included within the scope of the present invention.
Claims (7)
1. The utility model provides a phosphorus trichloride rectification purification device, the device includes rectifying still (1), erects rectifying column (2) that set up and rectifying column cap (3) that set up on rectifying column (2) on rectifying still (1), its characterized in that: the bottom of the inner side of the rectifying still (1) is provided with a resistance heating device (8), a quartz ring packing area (10) is arranged in the rectifying column (2), the outer side of the rectifying column (2) is provided with a heating insulation layer (11), a cooling reflux fractionating device (12) is arranged on the rectifying column head (3), and the rectifying still (1), the rectifying column (2) and the rectifying column head (3) are connected with each other through flanges.
2. The rectification and purification device of phosphorus trichloride as claimed in claim 1, wherein: a feed inlet (5), a safe pressure relief opening (4), a steam outlet (9) and a kettle temperature monitoring opening (19) are arranged at the upper end of the rectifying kettle (1); the bottom of the rectifying still (1) is provided with a residual liquid discharge port (7), and the position of the transverse side surface of the rectifying still (1) is provided with a liquid level monitoring device (6).
3. The rectification and purification device of phosphorus trichloride as claimed in claim 2, wherein: the residual liquid discharge port (7) and the feed port (5) are both connected with a ball valve, and the steam discharge port (9) is connected with the rectifying column (2) through a flange.
4. The rectification and purification device of phosphorus trichloride as claimed in claim 1, wherein: a cooling water outlet (13), a cooling water inlet (14), a tail gas discharge outlet (15) and a product distillation outlet (16) are respectively arranged on the cooling reflux fractionating device (12); wherein, cooling water outlet (13), cooling water inlet (14), tail gas discharge port (15) all set up the top at cooling reflux fractionating device (12), and the bottom of cooling reflux fractionating device (12) is "V" shape structure, and product distillation outlet (16) sets up the bottom at cooling reflux fractionating device (12).
5. The rectification and purification device of phosphorus trichloride as claimed in claim 1, wherein: the resistance heating device (8) is of a tubular resistance structure, a thermocouple is arranged on the resistance heating device (8), and the thermocouple and the resistance wire are connected with the temperature controller through a main power switch.
6. The rectification and purification device of phosphorus trichloride as claimed in claim 1, wherein: the heating insulation layer (11) is of a structure of annularly winding a resistance wire, a temperature measuring hole (18) of the rectification column head is formed in the rectification column head (3), a thermocouple is arranged in the temperature measuring hole (18) of the rectification column head, and the thermocouple and the resistance wire are connected to a temperature controller through a main power switch.
7. The rectification and purification device of phosphorus trichloride as claimed in claim 1, wherein: a cooling water jacket structure is arranged in the cooling reflux fractionation device (12); the cooling reflux fractionating device (12) is connected with the thermocouple temperature monitoring device and the DCS interlocking automatic control device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020184088.8U CN212166569U (en) | 2020-02-19 | 2020-02-19 | Phosphorus trichloride rectification purification device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020184088.8U CN212166569U (en) | 2020-02-19 | 2020-02-19 | Phosphorus trichloride rectification purification device |
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| Publication Number | Publication Date |
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| CN212166569U true CN212166569U (en) | 2020-12-18 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202020184088.8U Active CN212166569U (en) | 2020-02-19 | 2020-02-19 | Phosphorus trichloride rectification purification device |
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| CN (1) | CN212166569U (en) |
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Effective date of registration: 20230411 Address after: 610036 Shu Han Road, Jinniu District, Chengdu, Sichuan Province, No. 333 Patentee after: DONGFANG ELECTRIC Corp. Address before: 614200 No. 88, Fubei Road, Emeishan City, Leshan City, Sichuan Province Patentee before: EMEI SEMICONDUCTOR MATERIALS INSTITUTE |
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