JPH0816583B2 - Carbon monoxide separation and purification equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a carbon monoxide-producing gas or the like produced by oxidizing a by-product gas of a steel mill, a coke oven gas, propane, butane, or the like. The present invention relates to an apparatus for separating and purifying carbon monoxide for separating carbon.

[Conventional technology]

Because rich in carbon monoxide (CO) is reactive, it has been used as a raw material for synthetic chemistry, especially in recent years, are considered the most important carbon source among C ₁ chemistry. CO above
Is contained in a large amount in by-product gas from factories, including steelworks, and conventionally, at best, thermal energy is only recovered as fuel. However, an increase in demand for CO in recent years has led to the development of an apparatus for separating and recovering CO from the above-mentioned by-product gas. Recently, in view of the importance of CO as described above, an apparatus for separating and recovering CO from a CO raw material gas produced by oxidizing propane, butane, or the like has been proposed. An adsorbent such as zeolite is mainly used for these devices, and a device for concentrating and collecting CO by this adsorbent and a COSORB (CO
Two types of devices are used, one using a SORB) solution. However, the adsorption-separation device (based on the PSA method) that uses the above-mentioned adsorbent requires a large number of valves in the device itself, and at the same time, it is necessary to switch the adsorbent by valve operation and recycle it. Is complicated, and complicated valve operation is required. Moreover, since the recovery rate of CO from the raw material gas is low, it is necessary to mix waste gas with the raw material gas again to separate and collect CO, which has a drawback that running cost becomes high and product CO cost becomes high. are doing. In addition, there is a drawback that only high-purity CO can be obtained because only CO with a purity of about 99.5% can be obtained.

[Problems to be solved by the invention]

The device for carrying out the Cossorb method has the advantage that it does not require as many valves as the PSA device described above, for example:
Realize separation and recovery of CO from by-product gas such as converter gas. The composition of the converter gas is CO; 68-72 vol%, C
O ₂ ; 13 to 17 vol%, N ₂ ; 11 to 16 vol%, H ₂ ; 0.8 to 1.3 vol%, O ₂ ;
0.3-0.5vol%, other than trace components such as ammonia, hydrogen sulfide, sulfur dioxide, dust and 7%
Contains some moisture. FIG. 3 shows an example of a cosorb apparatus for such a gas. In the drawing, reference numeral 60 denotes a source gas supply source made of converter gas, and reference numeral 61 denotes a compressor, which compresses and raises the pressure of the source gas. In the compressor 61, dust is collected by the oil of the compressor 61 and removed by a filter provided in an oil circulation system for cooling the oil. Reference numeral 62 denotes a brine cooler for preliminary dehumidifying the pressurized raw material gas. Reference numeral 63 denotes an adsorption column filled with activated carbon, which adsorbs and removes sulfur and ammonia in the raw material gas. Numeral 64 denotes a set of two adsorption tubes filled with synthetic zeolite, which adsorb and remove water and carbon dioxide. The pair of suction cylinders 64 are alternately used. Reference numeral 65 denotes an absorption cylinder, which makes the raw material gas from which the impurities have been removed and dehumidified come into countercurrent contact with the cosorb liquid flowing down from the upper part of the tower so that CO in the raw material gas is selectively absorbed by the cosorb liquid. . The Cossorb solution is a solution of CuAlCl ₄ dissolved in toluene, and selectively absorbs CO at a low temperature and emits CO at a high temperature by the following reaction.

66 is a heat exchanger, which selectively absorbs CO in the absorption tower 65
The cossorb liquid delivered from the bottom of 65 is heated by exchanging heat with the liquid delivered from the bottom of the stripping tower 67. The diffusion tower
67, the CO-absorbing cosorb liquid flowed down from the top of the tower, and contact with the toluene vapor generated by heating the reboiler 68,
CO Absorbs CO in COSORB solution. Here, the cosorb solution that has released the CO is cooled and regenerated from the bottom of the stripping tower 67 through the heat exchanger 66 and the water cooler 69, and returned to the top of the absorption tower 65. Waste gas is sent out from the upper part of the absorption tower 65, cooled to −10 ° C. in the brine cooler 70, and toluene is recovered, and sent out to a piping system such as blast furnace gas. Then, the product CO (gas) is taken out from the upper part of the diffusion tower 67. In this case, a small amount of CO ₂ , N ₂ , H ₂ ,
Since O ₂ is dissolved, the product CO obtained from the stripping tower 67
These are mixed. 71 is a water cooler,
The above product CO is cooled and toluene is recovered. 72 is a compressor which boosts the above product CO. 73 is a brine cooler that cools the above product CO to -10 ° C and recovers toluene. 74 is a storage tank for product CO, which sends out product CO as appropriate.

However, in the above apparatus, impurities are inevitably mixed in the product CO, so that it is practically impossible to recover ultrahigh-purity carbon monoxide, and only about 99.5% is obtained. In addition, this device also has a drawback that the recovery rate of product CO is low.

The present invention has been made in view of such circumstances,
It is an object of the present invention to provide a carbon monoxide separation and purification apparatus capable of recovering ultra-high purity carbon monoxide at a high recovery rate.

[Means for solving problems]

In order to achieve the above object, the carbon monoxide separating and refining apparatus of the present invention comprises a compressing means for compressing a raw material gas containing carbon monoxide, a removing means for removing oxygen in the raw material gas by a heating reaction, and this oxygen. The heat exchange means for cooling the removed raw material gas in the heated state by utilizing the cold heat of the waste gas, and the moisture in the raw material gas is adsorbed and removed by the adsorbent to regenerate the adsorbent by the heat exchange means. A removing means that is performed by the waste gas heated by heat exchange; a removing means that liquefies and removes carbon dioxide gas in the raw material gas;
A heat exchange means for cooling the raw material gas from which water and carbon dioxide have been removed, and a rectification column for liquefying carbon monoxide in the raw material gas due to the difference in boiling points and storing it inside to separate and discharge the impurity gas A raw material gas supply path for guiding a raw material gas from the heat exchange means to the rectification column, a low temperature liquefied gas storage means for receiving and storing a low temperature liquefied gas from outside the apparatus, and a low temperature liquefied gas storage means An introduction path for leading the low temperature liquefied gas of the above to the rectification column as a cold source for carbon monoxide liquefaction, an extraction path for taking out the vaporized low temperature liquefied gas after finishing the action as a cold source in the rectification column, and the above At least one of an extraction path for taking out the stored liquefied carbon monoxide as product carbon monoxide and an extraction path for taking out the vaporized product of the stored liquefied carbon monoxide as product carbon monoxide is adopted.

[Action]

That is, this apparatus is an application of the cryogenic liquefaction separation method, in which the raw material gas that has passed through the compression means, the respective removal means, and the heat exchange means is introduced into the heat exchange means and cooled to an ultralow temperature, and this is refined. It is led to the distillation column, and inside it is further cooled by the cold heat of the low temperature liquefied gas supplied from the low temperature liquefied gas storage means to liquefy the CO in the raw material gas and convert the impure gas into a product gas and a waste gas as it is. It is separated and removed, and this is individually discharged from the rectification tower, while at the same time liquefied CO
Since carbon monoxide is taken out as it is, it becomes possible to recover ultra-high purity carbon monoxide. Further, N ₂ in the discharged impurity gas can be taken out as a product gas. That is, this device does not utilize the absorption and desorption of CO by heating and cooling of the cosorb liquid as in the above-mentioned cosorb device, or the absorption by the adsorbent as in the PSA device. Trace amounts of impure gases such as CO ₂ and N ₂ do not dissolve, and impure gases due to poor adsorption of the adsorbent do not mix, thus impairing the purity of the product carbon monoxide caused by these impure dissolved components. No phenomenon occurs.

Further, this apparatus is provided with a heat exchange means for cooling the heated raw material gas by using the cold heat of the waste gas, so that the raw material gas heated by the compression means and the removing means for removing oxygen by the heating reaction is Since the cold heat of the waste gas is used for cooling, the thermal efficiency is improved. Further, the heat exchanging means is provided with a removing means for adsorbing and removing water in the raw material gas with an adsorbent and regenerating the adsorbent with waste gas heated by heat exchange in the heat exchanging means. Since the adsorbent can be regenerated by using the heat of the waste gas heated by the heat exchange when the raw material gas is cooled, the heat can be further effectively used. Therefore, the purpose is to pre-cool the raw material gas,
Since it is not necessary to provide a gas heating means for regenerating the adsorbent, the device itself is simplified, and the device is small and inexpensive.

Next, the present invention will be described in detail based on examples.

〔Example〕

FIG. 1 shows an embodiment of the present invention. In the figure, 1 is a suction / storage tank for raw material gas, 2 is a filter for collecting and removing dust in the raw material gas, and 3 is a compressor for compressing and raising the pressure of the raw material gas. Reference numeral 4 denotes a catalyst tower containing a Pt catalyst, and hydrogen is added to the raw material gas compressed by the compressor 3, and the hydrogen and oxygen in the raw material gas are heated and reacted in an atmosphere at a temperature of about 250 ° C. to produce water. It is removed from the source gas. Reference numeral 5 denotes a heat exchanger for regeneration that brings a heated raw material gas (250 ° C.) into contact with a waste gas (low temperature) to be described later and cools by utilizing the cold heat thereof. 6 is a water-based heat exchanger that cools the raw material gas by water cooling, Reference numeral 7 denotes a drain separator for separating and removing water in the raw material gas. A discharge pipe 8 for discharging drain drainage is connected to the drain separator 7. Reference numeral 9 is an opening / closing valve provided in the discharge pipe 8. Reference numeral 10 denotes a source gas supply pipe for sending the source gas from which oxygen and water have been removed to a moisture adsorption column (dryer) 11, and includes open / close valves 12a and 12b. The adsorption cylinder 11 is composed of two pieces, and the inside thereof is filled with alumina gel as an adsorbent, and the adsorbent adsorbs and removes residual water and hydrocarbons such as ethane, propane, and acetylene in the raw material gas passing through the inside. It is about to do. Reference numeral 13a is a raw material gas delivery pipe for delivering the raw material gas from which water has been adsorbed and removed by the adsorption cylinder 11, and is provided with open / close valves 12c and 12d. This pair of two adsorption cylinders 11 has open / close valves 12a, 12b, 12
By switching c and 12d, it can be used alternately every 8 hours. Reference numeral 38c is a feed pipe for feeding a regeneration gas consisting of waste gas heated by heat exchange in the regeneration heat exchanger 5 to the adsorption cylinder 11 and provided with valves 12g and 12h. Further, 38d is an exhaust pipe provided with open / close valves 12e, 12f, which communicates with the waste gas discharge pipe 38b, and discharges the regenerated regenerated gas into the atmosphere. In this case, when one of the two adsorption cylinders 11 is adsorbing water or the like, the other one of the adsorption cylinders 11 has the other one of the on-off valves 12g, 12h, 12e, 12 described above.
Regeneration gas consisting of waste gas heated by opening and closing f is fed and regenerated. Reference numeral 14 is a heat exchanger that cools the raw material gas from which water has been adsorbed and removed in the adsorption column 11 to a low temperature, and 13b is a supply pipe that sends the raw material gas that has passed through the heat exchanger 14 to another heat exchanger 15. . Refrigerant Freon gas sent from Freon refrigerator 16 is circulated in this heat exchanger 15, and this Freon gas has a high boiling point CO ₂ among the gases contained in the raw material gas by cooling the raw material gas. It is designed to liquefy gas. 13c is a supply pipe,
A raw material gas containing the liquefied liquefied CO ₂ produced is fed into the centrifugal separator 17. The centrifuge 17 centrifuges the liquefied CO ₂ gas in the raw material gas and sends it to the liquefied CO ₂ tank 19 via the pipe 18. Reference numeral 20 is an opening / closing valve provided in the pipe 18. Reference numeral 21 is a set of two adsorption cylinders each containing a synthetic zeolite (Molecula Sieve) for adsorbing and removing the remaining impure gas such as CO ₂ from the raw material gas fed from the pipe 13d. Reference numeral 22a is a raw material gas supply pipe for sending the raw material gas from which O ₂ , H ₂ O, CO _{2 and the} like have been adsorbed and removed as described above to the heat exchanger 23. The heat exchanger 23 cools the raw material gas to an extremely low temperature and sends it to the rectification tower 24 via the low-temperature raw material gas supply pipe 22b. The rectification tower 24 includes a condenser 26 with a built-in condenser 25.
A medium pressure tower section 27 and a lower condenser section 28, and a large number of rectification shelves 29 are arranged in the medium pressure tower section 27. Then, a low temperature raw material gas feed pipe 22b extending from the heat exchanger 23 is opened in the lower condenser section 28 so as to feed the raw material gas cooled to an ultra low temperature. In the lower condenser section 28, the source gas (including N ₂ and H ₂ as impurities) in which O ₂ , H ₂ O and CO ₂ are removed and most of which is CO gas has almost no CO content. It is liquefied and N _{2 is} also liquefied to become the stored liquid 34, but H ₂ having a boiling point lower than those is not liquefied and remains in a gas state. This H ₂ gas is
Is discharged to the outside through the H ₂ extraction pipe 30 connected to the upper part of the. On the other hand, the liquefied CO containing the liquefied N ₂ (reservoir liquid 34) is fed into the upper part of the tower 27 through the introduction pipe 31. Reference numeral 32 denotes an expansion valve provided on the introduction pipe 31. Reference numeral 33 denotes a liquid level gauge, which controls the opening and closing and opening of the expansion valve 32 according to the liquid level of the stored liquid 34 in the lower condenser section 28 so as to keep the liquid level at a constant level. In the tower section 27, the stored liquid 34 containing liquefied CO as a main component is blown in a gas-liquid mixed state, and by the rectification action in the tower section 27,
CO with a high boiling point is liquefied and flows downward in the tower section 27, and is stored as product liquefied CO in the lower side of the tower section 27. Impurity gases such as H ₂ and N ₂ and the rest of CO are mixed gas state. Ascend above the tower 27. 35 is a condenser 25 in the upper part of the tower section 27 and in the partial condenser section 26.
It is a first reflux liquid pipe for connecting to and is adapted to feed the mixed gas rising above the tower section 27 into the condenser 25. Reference numeral 36 denotes a shielding plate, which forms a flow path for guiding the mixed gas to the first reflux liquid pipe 35, and the impurity gas (H ₂ , H ₂ ) is mixed with the mixed gas to prevent impure gas from staying at the top of the column. In the condenser 25, due to the difference in boiling point
CO is liquefied, and N ₂ , H _{2 and the} like are removed in a gaseous state from the condenser 25 through a waste gas pipe 37a extending upward. This waste gas pipe 37a is a waste gas pipe 37b, 37c.
The waste gas is heated via the heat exchangers 23 and 14 to reach a temperature near room temperature, and then sent to the regeneration heat exchanger 5. The waste gas further heated in the regeneration heat exchanger 5 (mainly N ₂ gas)
Is blown through the pipe 38a as a purge gas for removing the water content of the built-in adsorbent and regenerating the adsorbent into the adsorbent cylinder 11 on the regenerating side of the pair of two adsorbent cylinders 11. The waste gas is discharged into the atmosphere from the waste gas discharge pipe 38b. 39
Is a second reflux liquid pipe extending from the lower part of the condenser 25 of the rectification tower 24 to the upper part of the tower part 27, and the liquefied CO collected at the bottom part of the condenser 25 is placed in a tray 40 in the tower part 27. It is made to flow down as a reflux liquid. The liquefied CO that has flowed down into the receiving pan 40 overflows and flows downward in the tower section 27 as a reflux liquid. 41a is an extraction pipe, which communicates with the lower side of the tower 27,
The ultra-low temperature gas CO generated by the vaporization of the stored liquid CO at the bottom of the tower 27 is taken out as a product CO gas. This pipe 41a
Is in communication with the CO gas extraction pipe 41c through a pipe 41b, and after the product CO gas is heat-exchanged through the heat exchangers 23 and 14 to raise the temperature to room temperature, the CO gas extraction pipe 41c
Is being supplied to the outside as a product. 42 is a liquid nitrogen storage tank that receives supply of liquid nitrogen from the outside of the device and stores the liquid nitrogen, and the liquid nitrogen inside is sent into the dephlegmator section 26 of the rectification column 24 via the introduction path pipe 43. , Demultiplexer section 26
It is used as a cold source for the condenser 25 inside. 44 is the liquid nitrogen introduced. 45a is a delivery pipe for delivering vaporized nitrogen after finishing the action as cold in the dephlegmator section 26 of the rectification column 24, and communicating with the N ₂ gas extraction pipe 45c through the delivery pipe 45b, The vaporized nitrogen is heat-exchanged via the heat exchangers 23 and 14, and then sent out from the N ₂ gas extraction pipe 45c to be used. 46 is a product of liquefied CO 47 accumulated at the bottom of the tower section 27 of the rectification tower 24.
It is an extraction pipe that takes out as CO. 48 is the above product liquefaction
It is a CO storage tank, and product liquefaction from this storage tank 48
CO is taken out as appropriate. The extraction pipe 46 has a control valve
49 are provided. A liquid level controller 50 controls the control valve 49 in accordance with the liquid level so that the liquid level of the stored liquefied CO47 at the bottom of the rectification tower section 27 maintains a constant level. Further, the control valve 51 provided on the introduction path pipe 43 is also controlled by the liquid level controller 52 so that the liquid level of the liquid nitrogen in the dephlegmator section 26 of the rectification column 24 maintains a constant level. It is becoming like this. In addition, the heat exchanger 14 and the adsorption column 2
The 1 and the heat exchanger 23 and the rectification column 24 are housed in vacuum heat insulating containers 53 and 54, respectively, as shown by the dashed line in the figure.

This device is, for _{example, CO; 70.0vol%, CO 2} ; 17.0vol%, N
_The product CO is manufactured as follows, targeting the CO raw material gas composed of the converter gas and having the composition of ₂ ; 11.5vol%, H ₂ ; 1.0vol%, O ₂ ; 0.5vol%. That is, after the raw material gas sent from the intake and storage tank 1 of the raw material gas is removed by the filter 2, it is compressed by the compressor 3, and O ₂ in the compressed raw material gas is removed by the heating reaction in the catalyst tower 4. ₂ is removed and the raw material gas in a heated state is cooled by the regeneration heat exchanger 5 and the water-based heat exchanger 6, and water is removed by the drain separator 7, and then the residual water is adsorbed and removed by the adsorption column 11. Then,
The raw material gas from which O ₂ and H ₂ O have been removed is used as N ₂ gas and C from the rectification tower 24.
Heat exchanger 14 cooled by O 2 gas and waste gas
And cool to low temperature. Then, the raw material gas cooled to this low temperature is further cooled by the heat exchanger 15, the CO ₂ gas in the raw material gas is liquefied, and the raw material gas containing this liquefied CO ₂ is
The product is hung on a centrifuge 17, centrifuged, and sent to a product liquefied CO ₂ tank 19 via a pipe 18. On the other hand, liquefied C in the centrifuge 17
The raw material gas from which O ₂ has been removed and whose purity has been increased is sent to the adsorption column 21, and a small amount of CO ₂ gas remaining in the raw material gas is adsorbed and removed. In this way, the source gas from which O ₂ , H ₂ O, and CO ₂ have been removed (the main component is CO gas, which contains N ₂ gas and H ₂ gas as impurities, the temperature is approximately −50 ° C.) It is located on the downstream side of the heat exchanger 14 and is sent to the heat exchanger 23 which is cooled to a temperature lower than that of the heat exchanger 14 by the N ₂ gas, the CO gas and the waste gas from the rectification tower 24, and the ultra low temperature ( (About -172 ° C). Then, the raw material gas cooled to ultra-low temperature is passed through the rectification tower.
It is fed into the lower condenser section 28 of 24, and liquefied CO
CO and N ₂ in the raw material gas are liquefied and separated in the condensing pipe 28a cooled by, and H ₂ is released to the outside through the H ₂ extracting pipe 30 in a gaseous state. Then, liquefied CO containing liquefied N ₂ is introduced into the column section 27 of the rectification column 24 through the expansion valve 32 in a gas-liquid mixed state, and by the rectification action of the column section 27, in the raw material in the gas-liquid mixed state. CO is liquefied from the liquefied CO2 and stored as product liquefied CO47 at the bottom of the tower 27. At this time, the impure H ₂ and N ₂ gas in the raw material is not liquefied due to the difference in boiling points and rises upward in the tower section 27. Further, some of the CO in the above raw material is not liquefied, and the above H ₂ and N ₂ remain as gas.
It rises along with gas. The mixed gas of the ascending H ₂ , N ₂ and CO is fed from the first reflux liquid pipe 35 to the condenser 25 of the rectification column 24, where only the CO gas is liquefied due to the difference in boiling points. , And returns to the receiving tray 40 of the tower section 27 in the rectification column 24 via the second reflux liquid pipe 39 as the reflux liquid. On the other hand, H ₂ , N ₂
The gas is taken out from the upper part of the condenser 25 by the waste gas pipe 37a. This waste gas exchanges heat with the raw material gas in the heat exchangers 23, 14 while passing through the waste gas pipes 37b, 37c communicating with the waste gas pipe 37a, and is sent to the regeneration heat exchanger 5.
Then, it is heat-exchanged with the raw material gas in the heated state by the regeneration heat exchanger 5 and is heated and sent out to regenerate the adsorbent in the adsorbing cylinder 11 in the regenerating operation and then release it into the atmosphere. The product liquefied CO 47 collected at the bottom of the tower 27 in the rectification tower 24 is
The liquefied product is taken out from the product liquefied CO extraction pipe 46, temporarily stored in the storage tank 48, and then used as appropriate. Further, the CO gas generated by the vaporization of the product liquefied CO47 and staying on the liquid surface of the stored product liquefied CO47 in the tower section 27 passes through the extraction pipes 41a, 41b, the CO gas extraction pipe 41c, and heat The heat is exchanged in the exchangers 23 and 14 and taken out. Further, the liquid nitrogen sent from the liquid nitrogen storage tank 42 into the dephlegmator section 26 is vaporized after finishing the cooling action of the condenser 25 and then sent through the delivery pipes 45a, 45b and N ₂ gas extraction pipe 45c, Like the CO gas, it is heat-exchanged in the heat exchangers 23 and 14 and taken out.

As described above, this apparatus includes the filter 2, the catalyst tower 4,
Liquefied CO products obtained by liquefying and separating the raw material gas from which impurities have been removed by the drain separator 7, adsorption column 11, centrifugal separator 17, and adsorption column 21 in the rectification column 24 to produce liquefied CO. Becomes ultra-high purity. Moreover, the CO in the raw material gas fed to the lower condenser section 28 of the rectification column 24 due to changes in the composition of the raw material gas
Even if the amount fluctuates and the liquefaction amount fluctuates, the liquid level gauge 33 controls the expansion valve 32, the liquid level regulator 52 controls the control valve 51 of the liquefied nitrogen supply introduction passage pipe 43, and the liquid level regulator 50. This can be automatically controlled by controlling the control valve 49 of the product liquefaction CO extraction pipe 46. Therefore, high purity product liquefied CO and product CO gas having a constant purity can always be produced even if the component composition of the source gas fluctuates. Variations in the amount of inflow of the source gas can be similarly handled. In addition, this device is a dephlegmator section in the rectification tower 24.
In the condenser 25 of 26, since a part of the raw material gas in the rectification column 24 is constantly guided and liquefied, after a predetermined amount of liquefied CO is accumulated in the condenser 25, liquefied CO generated thereafter Will always return to the column portion 27 of the rectification column 24 as a reflux liquid. Therefore, variations in product purity due to intermittent supply of reflux liquid from the condenser 25 (due to interruption of the flow of reflux liquid, there is no reflux liquid in the rectification shelf, and gas blow-through phenomenon occurs, resulting in a decrease in product purity. , And the purity recovers when the flow is resumed), and product liquefied CO of stable purity can always be supplied. Further, this device has an effect that CO gas and N ₂ gas can be supplied as products as described above, and also has an effect that waste gas can be used for drying and regeneration of the adsorbent of the moisture adsorption column.

FIG. 2 shows another embodiment of the present invention. That is, the apparatus shown in FIG. 2 does not produce both product liquefied CO and product CO gas as in the apparatus shown in FIG. 1, but can produce only product CO gas. Back-up line 55 to respond to increased demand
Is provided. The back-up line 55 includes a liquefied CO evaporator 56, a pipe 55a for supplying liquefied CO from the product CO storage tank 48, and a CO gas vaporized and generated by the liquefied CO evaporator 56 to a product CO gas extraction pipe 41c. Guide pipe 55 to be sent
b, a pressure adjusting valve 57 provided on the guide pipe 55b. The pressure control valve 57 is on the secondary side (use side)
When the pressure falls below the set pressure, the valve is opened or the opening degree of the valve is adjusted so that the pressure on the secondary side maintains the set pressure. In this back up line 55, when the pressure in the product CO gas extraction pipe 46 decreases due to a failure of the rectification tower line or a large increase in the demand amount of the product CO gas, the pressure control valve 57 is activated. Since the opening operation is performed, liquefied CO flows from the product CO storage tank 48 to the liquefied CO evaporator 56 and vaporizes,
The generated vaporized CO gas is used as product CO gas in the above extraction pipe.
It is supposed to flow into 41c. Other parts are the same as those of the apparatus shown in FIG.

By providing the back-up line 55 as described above, this equipment can vaporize the liquefied CO when the demand for the product CO gas increases significantly when the rectification tower line fails or the rectification tower alone cannot handle it. Activate the device 56 and
The liquefied CO in the storage tank 48 can be vaporized as product CO gas, so that the supply of the product CO gas is not interrupted and the purity of the product CO gas does not decrease when the demand increases significantly.

In the apparatus shown in Fig. 1, the product CO gas extraction pipe
It is also possible to remove 41a and turn all of the product carbon monoxide into liquefied CO.

In the above embodiment, the liquid nitrogen in the liquid nitrogen storage tank 42 is used as the cold source for liquefying carbon monoxide, but the cold source is not limited to this. In addition to the liquid nitrogen, a low-temperature liquefied gas such as liquid oxygen, liquid hydrogen, or liquefied methane (LNG) can be appropriately used. In some cases, liquefied CO produced by another device can be used as a cold source. These low-temperature liquefied gases are used by installing a storage tank having the same structure as that of the liquid nitrogen storage tank 42 of the above embodiment and connecting the storage tank with the rectification tower 24 by a pipe.

〔The invention's effect〕

Since the apparatus for separating and purifying carbon monoxide of the present invention is configured as described above, it is possible to efficiently produce ultra-high-purity carbon monoxide. In addition, since this device uses a low-temperature liquefied gas supplied to the low-temperature liquefied gas storage means from outside the device as a cold source for the rectification tower and the like, it does not require a rotating device such as an expansion turbine, and therefore, can be rotated. Operation of equipment,
In addition to the need for troublesome maintenance and the like, it is possible to reduce the size of the entire device. Moreover, in this device, the raw material gas heated by the compressing means and the removing means for removing oxygen by the heating reaction is cooled by utilizing the cold heat of the waste gas, so that the thermal efficiency is improved. Further, since the heat of the waste gas heated by the heat exchange at the time of cooling the raw material gas can be used to regenerate the adsorbent, the heat can be further effectively used. Therefore, it is not necessary to purposely provide a precooling means for the raw material gas, a gas heating means for regenerating the adsorbent, and the like, and the apparatus itself is simplified, which is small and inexpensive.

[Brief description of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention, FIG. 2 is a block diagram of another embodiment, and FIG. 3 is a block diagram of a conventional example. 3 ... Compressor, 4 ... Catalyst tower, 5,14,15,23 ... Heat exchanger, 7 ... Drain separator, 11 ... Adsorption cylinder, 17 ... Centrifugal separator, 22b ... Raw material gas Inlet pipe, 24 …… rectification tower, 37
a, 37b, 37c …… waste gas pipe, 38a …… pipe, 41c …… C
O gas extraction pipe, 42 ...... Liquid nitrogen storage tank, 43 …… Introduction pipe, 45c …… N ₂ gas extraction pipe, 46 …… Extraction pipe

Claims (2)

[Claims] 1. A compressing means for compressing a raw material gas containing carbon monoxide, a removing means for removing oxygen in the raw material gas by a heating reaction, and a raw material gas in a heated state from which the oxygen has been removed as waste gas. A heat exchanging means for cooling by utilizing cold heat, and a removing means for adsorbing and removing water in the raw material gas by an adsorbent and regenerating the adsorbent by waste gas heated by the heat exchange in the heat exchanging means. Removing means for liquefying and separating and removing carbon dioxide gas in the raw material gas;
A heat exchange means for cooling the raw material gas from which water and carbon dioxide have been removed, and a rectification column for liquefying carbon monoxide in the raw material gas due to the difference in boiling points and storing it inside to separate and discharge the impurity gas A raw material gas supply path for guiding a raw material gas from the heat exchange means to the rectification column, a low temperature liquefied gas storage means for receiving and storing a low temperature liquefied gas from outside the apparatus, and a low temperature liquefied gas storage means An introduction path for leading the low temperature liquefied gas of the above to the rectification column as a cold source for carbon monoxide liquefaction, an extraction path for taking out the vaporized low temperature liquefied gas after finishing the action as a cold source in the rectification column, and the above At least one of an extraction path for taking out the stored liquefied carbon monoxide as product carbon monoxide and an extraction path for taking out the vaporized product of the stored liquefied carbon monoxide as product carbon monoxide is provided. Carbon oxide Away purification equipment. 2. The apparatus for separating and purifying carbon monoxide according to claim 1, wherein the low-temperature liquefied gas is liquid nitrogen.