Summary of the invention
The object of the invention is to overcome weak point that prior art exists and provide a kind of trifluoromethane purification devices, high-purity trifluoromethane can be obtained by this device; In addition, present invention also offers a kind of method adopting described purification devices purifying trifluoromethane.
For achieving the above object, the technical scheme taked: a kind of trifluoromethane purification devices, the adsorption unit that described device comprises rectifier unit and is connected with described rectifier unit, described rectifier unit comprises the one-level rectifier unit, two-stage rectification device and the three grades of rectifier units that connect successively, described adsorption unit comprises the cryogenic absorption device and filling unit that connect successively, and the cryogenic absorption device of described adsorption unit is connected with described rectifier unit.
Trifluoromethane purification devices of the present invention, the mode purifying trifluoromethane adopting rectifying and Adsorption Phase to combine, can obtain highly purified trifluoromethane by purifying, reach the service requirements of semicon industry.
As the preferred implementation of trifluoromethane purification devices of the present invention, described device comprises a set of rectifier unit and a set of adsorption unit, and the cryogenic absorption device of described adsorption unit is connected with three grades of rectifier units of described rectifier unit.
As the preferred implementation of trifluoromethane purification devices of the present invention, described device comprises a set of rectifier unit and two cover adsorption units, described two cover adsorption units are respectively the first adsorption unit and the second adsorption unit, the cryogenic absorption device of described first adsorption unit is connected with three grades of rectifier units of described rectifier unit, and the cryogenic absorption device of described second adsorption unit is connected with the two-stage rectification device of described rectifier unit.Divide for Raw material recombination the purifying that content is less and client's counterweight component requirements is not high, be connected to a set of adsorption unit equally in two-stage rectification outlet, do not need to enter three grades of rectifying, decrease the loss of raw material and low-temperature receiver, and ensure removing of other impurity.
As the preferred implementation of trifluoromethane purification devices of the present invention, described one-level rectifier unit comprises one-level rectifying tower, the first grade discharging pipeline that the top of described one-level rectifying tower is connected with first-stage condenser and is connected with the top of described first-stage condenser, the one-level material inlet pipeline that the middle part of described one-level rectifying tower is connected with one-level pre-cooler and is connected with the top of described one-level pre-cooler, the thick products export pipeline of one-level that the bottom of described one-level rectifying tower is connected with one-level reboiler and is connected with the bottom of described one-level reboiler;
Described two-stage rectification device comprises two-stage rectification tower, described two-stage rectification tower bottom be connected with secondary reboiler and with the thick product inlet pipeline of secondary be connected bottom described secondary reboiler, the top of described two-stage rectification tower is connected with secondary condenser and the secondary discharge tube that is connected with described secondary condenser and the thick products export pipeline of secondary;
Described three grades of rectifier units comprise three grades of rectifying tower, the bottom of described three grades of rectifying tower is connected with three grades of reboilers, three grades of thick product inlet pipelines that the middle part of described three grades of rectifying tower is connected with three grades of pre-coolers and is connected with described three grades of pre-cooler tops, the top of described three grades of rectifying tower is connected with three grades of condensers and three grades of discharge tubes being connected with described three grades of condensers and three grades of thick products export pipelines;
The one-level thick products export pipeline of described one-level rectifier unit is connected with the thick product inlet pipeline of the secondary of described two-stage rectification device by communicating valve, and the secondary thick products export pipeline of described two-stage rectification device is connected with three grades of thick product inlet pipelines of described three grades of rectifier units by communicating valve.
One-level rectifying described above is mainly used in removing light constituent, as H
2, N
2, O
2, CF
4, CO
2deng, two-stage rectification is mainly used in removing most of heavy constituent, as CHCl
3, CCl
2f
2, CHClF
2, C
2hF
5deng, three grades of rectifying is mainly used in removing easily and trifluoromethane forms the very close heavy constituent of azeotropic or boiling point and trifluoromethane, as CHClF
2, C
2hF
5deng.
As the preferred implementation of trifluoromethane purification devices of the present invention, the surge tank that described cryogenic absorption device comprises adsorber and is connected with described adsorber;
Described filling unit comprises interconnective molding machine, pressurized adsorbent device and strainer;
The surge tank of described cryogenic absorption device is connected with the molding machine of described filling unit; The adsorber of described cryogenic absorption device is connected with described rectifier unit.
As the preferred implementation of trifluoromethane purification devices of the present invention, described strainer comprises grade one filter and secondary filter, secondary filter is increased at the outlet conduit of pressurized adsorbent device, it act as and removes bead ion, makes trifluoromethane product meet the service requirements of semicon industry.
In a particular embodiment, described absorber bottoms is connected with the top of described surge tank; The Main Function of cryogenic absorption device is deep removal impurity, CO as very close in BP polar and trifluoromethane
2, C
2hF
5, CHClF
2deng.Increase pressurized adsorbent device in the outlet of molding machine one stage of compression, carry out pressurized adsorbent, greatly strengthen the adsorption effect of molecular sieve, realize H
2o, CO
2deep removal.Increase secondary filter at pressurized adsorbent outlet conduit, effect removes bead ion, makes trifluoromethane product meet semicon industry service requirements.In a particular embodiment, the bottom of described surge tank is connected with the one stage of compression import of described moulding press.In a particular embodiment, described adsorber top is connected with the top of three grades of rectifier units; In a particular embodiment, described first adsorber top is connected with the top of three grades of rectifier units, and described second adsorber top is connected with the top of two-stage rectification device.
As the preferred implementation of trifluoromethane purification devices of the present invention, at least one filler in 5A molecular sieve, 13X molecular sieve, carbonic acid gas Special adsorbent is housed in the adsorber of described cryogenic absorption device.The adsorber of cryogenic absorption device, built with filler, generally has molecular sieve, gac etc., for the character of trifluoromethane and its impurity, generally adopts 5A molecular sieve, 13X molecular sieve and carbonic acid gas Special adsorbent.
As the preferred implementation of trifluoromethane purification devices of the present invention, at least one filler in 3A molecular sieve, 4A molecular sieve and 5A molecular sieve is housed in the pressurized adsorbent device of described filling unit.3A molecular sieve, 4A molecular sieve, 5A molecular sieve generally can be loaded, with to H in described pressurized adsorbent device
2o carries out deep removal, makes to remove to reach H
2o≤0.5ppm.
In addition, trifluoromethane purification devices of the present invention, all can arrange discharge port in one-level, secondary, three grades of rectifier bottoms, for arranging raffinate in tower, ensures that gas purity and system are normally run.Equally, at one-level, secondary, three grades of rectifying tower gas emission pipes, all connect recovery channel, utilize the liguefied nitrogen of discharge, the tail gas that discharge tube discharges all is reclaimed, carries out secondarily purified, realize the maximum utilization of resources, avoid loss.
In addition, the present invention also provides a kind of method adopting device purifying trifluoromethane as described above, said method comprising the steps of:
(1) purge whole purification devices with high pure nitrogen, then vacuumize process to whole purification devices, be extracted into pressure is below 5pa always;
(2) liquid nitrogen is passed into the first-stage condenser shell side of one-level rectifier unit, one-level pre-cooler shell side, trifluoromethane raw material is entered one-level rectifying tower from one-level material inlet pipeline by one-level pre-cooler tube side with the flow velocity of 50Nm3/h, charging is stopped when one-level rectifying tower liquid level arrives 75%, in one-level rectifying tower, temperature remains on-28 ~-35 DEG C, now opens first grade discharging pipeline with flow 1.5Nm
3/ h starts emptying, opens one-level reboiler terminal valve, keeps one-level rectifying tower internal pressure to be 0.5 ~ 0.7Mpa, starts rectifying, to detecting N in trifluoromethane raw material
2, O
2, CF
4and CO
2after content is qualified, complete one-level rectifying;
(3) communicating valve of the thick product inlet pipeline of secondary in one-level thick products export pipeline and two-stage rectification device in one-level rectifier unit is opened, to the trifluoromethane raw material after one-level rectifying be completed to the charging of two-stage rectification tower, control one-level rectifying tower internal pressure 0.5 ~ 0.8Mpa, with flow 30Nm
3the flow velocity of/h is to the charging of two-stage rectification tower, the communicating valve between one-level thick products export pipeline and the thick product inlet pipeline of secondary is closed when one-level rectifying tower liquid level residue 10 ~ 15%, open secondary reboiler terminal valve and carry out rectifying, controlling two-stage rectification pressure tower is 0.3 ~ 0.5Mpa, in two-stage rectification tower, temperature controls between-25 ~-48 DEG C, to detecting N in trifluoromethane raw material
2, O
2, CF
4, CO
2, CHCl
3, CCl
2f
2, CHClF
2and C
2hF
5after content is qualified, complete two-stage rectification;
(4) open the communicating valve in secondary thick products export pipeline and three grades of rectifier units between three grades of thick product inlet pipelines in two-stage rectification device, will the trifluoromethane raw material after two-stage rectification be completed with flow 30Nm
3the flow velocity of/h is to three grades of rectifying tower chargings, and close communicating valve when two-stage rectification tower liquid level residue 5 ~ 10%, controlling three grades of Rectification column pressures is 0.2 ~ 0.3Mpa, and in three grades of rectifying tower, temperature controls between-45 ~-48 DEG C, to detecting N in trifluoromethane raw material
2, O
2, CF
4, CO
2, CHCl
3, CCl
2f
2, CHClF
2and C
2hF
5after content is qualified, complete three grades of rectifying;
(5) the trifluoromethane raw material after completing three grades of rectifying is entered into the adsorber of cryogenic absorption device by three grades of thick products export pipelines, vacuumize process 6h at DEG C temperature of 250 DEG C≤T≤300 after, with 0.4MPa helium pressurize connecting system, after adsorber, CO
2reach deep removal, to CO
2after≤0.5ppm, product is sent in surge tank, complete cryogenic absorption;
(6) sent into by the product in surge tank in the molding machine of filling unit, start molding machine, open molding machine inlet valve, the trifluoromethane after cryogenic absorption enters into pressurized adsorbent device by the one stage of compression outlet of molding machine, carries out pressurized adsorbent, to H
2o carries out deep removal, H
2o reaches deep removal, H
2o≤0.5ppm, the trifluoromethane after pressurized adsorbent enters molding machine by strainer, after molding machine secondary exit port pressure to 0.5MPa, opens molding machine outlet valve and starts to fill.
In step described above (2), to detecting N in trifluoromethane raw material
2, O
2, CF
4and CO
2after content is qualified, complete one-level rectifying, refer to detection gas phase O
2< 1ppm, N
2< 4ppm, CF
4< 0.5ppm, CO
2after < 3ppm, complete one-level rectifying, namely qualified standard is gas phase O
2< 1ppm, N
2< 4ppm, CF
4< 0.5ppm, CO
2< 3ppm.
In step described above (3), to detecting N in trifluoromethane raw material
2, O
2, CF
4, CO
2, CHCl
3, CCl
2f
2, CHClF
2and C
2hF
5after content is qualified, complete two-stage rectification, refer to detection liquid phase O
2< 1ppm, N
2< 4ppm, CF
4< 0.5ppm, CO
2< 1.5ppm, CHCl
3+ CCl
2f+C
2hF
5< 5ppm, CHClF
2after < 10ppm, complete two-stage rectification, namely qualified standard is liquid phase O
2< 1ppm, N
2< 4ppm, CF
4< 0.5ppm, CO
2< 1.5ppm, CHCl
3+ CCl
2f+C
2hF
5< 5ppm, CHClF
2< 10ppm.
In step described above (4), to detecting N in trifluoromethane raw material
2, O
2, CF
4, CO
2, CHCl
3, CCl
2f
2, CHClF
2and C
2hF
5after content is qualified, complete three grades of rectifying, refer to detection gas phase O
2< 1ppm, N
2< 4ppm, CF
4< 0.5ppm, CO
2< 1.5ppm, CHCl
3+ CCl
2f+CHClF
2+ C
2hF
5after < 5ppm, complete three grades of rectifying, namely qualified standard is gas phase O
2< 1ppm, N
2< 4ppm, CF
4< 0.5ppm, CO
2< 1.5ppm, CHCl
3+ CCl
2f+CHClF
2+ C
2hF
5< 5ppm.
When Raw material recombination divide content more and client's counterweight component requirements is higher time, method described above can be adopted to carry out purifying to trifluoromethane raw material, namely first then enter into adsorption unit through three grades of rectifying.
In addition, the present invention also provides another to adopt the method for device purifying trifluoromethane as described above, said method comprising the steps of:
(1) purge whole purification devices with high-purity gas, then vacuumize process to whole purification devices, be extracted into pressure is below 5pa always;
(2) refrigerant is passed into the first-stage condenser shell side of one-level rectifier unit, one-level pre-cooler shell side, trifluoromethane raw material is entered one-level rectifying tower from one-level material inlet pipeline by one-level pre-cooler tube side with the flow velocity of 50Nm3/h, charging is stopped when one-level rectifying tower liquid level arrives 75%, in one-level rectifying tower, temperature remains on-28 ~-35 DEG C, now opens first grade discharging pipeline with flow 1.5Nm
3/ h starts emptying, opens one-level reboiler terminal valve, keeps one-level rectifying tower internal pressure to be 0.5 ~ 0.7Mpa, starts rectifying, to detecting N in trifluoromethane raw material
2, O
2, CF
4and CO
2after content is qualified, complete one-level rectifying;
(3) communicating valve of the thick product inlet pipeline of secondary in one-level thick products export pipeline and two-stage rectification device in one-level rectifier unit is opened, to the trifluoromethane raw material after one-level rectifying be completed to the charging of two-stage rectification tower, control one-level rectifying tower internal pressure 0.5 ~ 0.8Mpa, with flow 30Nm
3the flow velocity of/h is to the charging of two-stage rectification tower, the communicating valve between one-level thick products export pipeline and the thick product inlet pipeline of secondary is closed when one-level rectifying tower liquid level residue 10 ~ 15%, open secondary reboiler terminal valve and carry out rectifying, controlling two-stage rectification pressure tower is 0.3 ~ 0.5Mpa, in two-stage rectification tower, temperature controls between-25 ~-48 DEG C, to detecting N in trifluoromethane raw material
2, O
2, CF
4, CO
2, CHCl
3, CCl
2f
2, CHClF
2and C
2hF
5after content is qualified, complete two-stage rectification;
(4) the trifluoromethane raw material after two-stage rectification will be completed to be entered into by the thick products export pipeline of secondary the adsorber of the second adsorption unit cryogenic absorption device, vacuumize process 6h at DEG C temperature of 250 DEG C≤T≤300 after, with 0.4MPa helium pressurize connecting system, after adsorber, CO
2reach deep removal, to CO
2after≤0.5ppm, product is sent in surge tank, complete cryogenic absorption;
(5) sent into by the product in surge tank in the molding machine of filling unit, start molding machine, open molding machine inlet valve, the trifluoromethane after cryogenic absorption enters into pressurized adsorbent device by the one stage of compression outlet of molding machine, carries out pressurized adsorbent, to H
2o carries out deep removal, H
2o reaches deep removal, H
2o≤0.5ppm, the trifluoromethane after pressurized adsorbent enters molding machine by strainer, after molding machine secondary exit port pressure to 0.5MPa, opens molding machine outlet valve and starts to fill.
In step described above (2), to detecting N in trifluoromethane raw material
2, O
2, CF
4and CO
2after content is qualified, complete one-level rectifying, refer to detection gas phase O
2< 1ppm, N
2< 4ppm, CF
4< 0.5ppm, CO
2after < 3ppm, complete one-level rectifying, namely qualified standard is gas phase O
2< 1ppm, N
2< 4ppm, CF
4< 0.5ppm, CO
2< 3ppm.
In step described above (3), to detecting N in trifluoromethane raw material
2, O
2, CF
4, CO
2, CHCl
3, CCl
2f
2, CHClF
2and C
2hF
5after content is qualified, complete two-stage rectification, refer to detection liquid phase O
2< 1ppm, N
2< 4ppm, CF
4< 0.5ppm, CO
2< 1.5ppm, CHCl
3+ CCl
2f+C
2hF
5+ CHClF
2after < 5ppm, complete two-stage rectification, namely qualified standard is liquid phase O
2< 1ppm, N
2< 4ppm, CF
4< 0.5ppm, CO
2< 1.5ppm, CHCl
3+ CCl
2f+C
2hF
5+ CHClF
2< 5ppm.
When Raw material recombination divide content less and client's counterweight component requirements is not high time, method described above can be adopted to carry out purifying to trifluoromethane raw material, namely then directly enter into adsorption unit through two-stage rectification.
The present invention also provides a kind of trifluoromethane adopting method described above to prepare, and the purity of described trifluoromethane is 99.999%.Adopt the trifluoromethane that the method for the invention prepares, purity is higher, can reach the service requirements of semicon industry.
Beneficial effect of the present invention is: the invention provides a kind of trifluoromethane purification devices, and compared with prior art, after employing apparatus of the present invention purifying, the purity of trifluoromethane is higher, and this device is simple to operate, and its purifying process is complete, reliable, and repeatability is strong.Not only consider removing of customary impurities, and the carbonic acid gas being difficult to remove, difluorochloromethane, pentafluoride ethane, water, granularity are removed to acceptability limit, product purity 99.999%, meet semicon industry service requirements.