JPS6078613A - Purification of carbon monoxide from gaseous mixture containing carbon monoxide by using adsorbing method - Google Patents

Abstract

PURPOSE:To economically obtain high concn. carbon monoxide according to a pressure swing type adsorptive separation method, by using an adsorbent having selectivity to carbon dioxide and carbon monoxide. CONSTITUTION:Stock gas is introduced into an adsorbing tower A under pressure and a valve 1 is opened to raise pressure from a vacuum state. The valve 1 and an outlet valve 2 are closed while a valve 3 is opened to reduce and release the internal pressure of the adsorbing tower A to bring the same to the vicinity of atmospheric pressure. The valve 3 is closed while a valve 4 is opened from the lower part of the adsorbing tower and vacuum exhaustion is performed by using a vacuum pump to desorb a carbon dioxide component. The waste gas from a denitrification PSA apparatus is utilized by opening a valve 5 and carbon dioxide is expelled from the adsorbent by accompany adsorption with purge gas. A valve 6 is opened to perform pressurization by the product gas.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses a pressure fluctuation adsorption separation method (PSA method) to extract a high-purity product from raw material gas containing exhaust gas from a converter or blast furnace, mainly carbon monoxide, carbon dioxide, and carbon dioxide. Concerning a method for obtaining carbon oxide.

IIl! Exhaust gas generated from smelting vessels at ironworks is
Contains a relatively large amount of CO gas. The composition of converter exhaust gas and blast furnace exhaust gas is within the range shown below.
Sections 1 to 10 Blast furnace exhaust gas 2()-30 Sections 2 and 30'
164()-60% 1~10'1 If these wares
If high-purity gas can be recovered at low cost, it can be used as a raw material for synthetic chemicals or as a gas to be injected into the molten metal in a refining vessel.When considering synthetic chemical raw materials and this CO gas, Since the reaction is usually carried out under high temperature and high pressure conditions, it is essential to remove oxidizing gases that can damage the reaction vessel, and it is necessary to reduce the CO2 floatation level as much as possible.Also, it is necessary to increase the reaction efficiency. In order to achieve this, it is desirable to remove as much as possible the 1.cm of N2 that normally participates in the reaction.On the other hand, the operation of blowing gas into the refining vessel, which aims to improve the efficiency of refining molten metal, is widely practiced. However, from the viewpoint of avoiding an increase in the concentration of impure gas components (N2, N2, etc.) in molten metal, expensive Ar gas is usually used. If high-purity Co gas can be recovered from furnace gas or blast furnace gas at low cost, it is possible to replace it with At.In this case, the N2 concentration of high-purity III CO gas will prevent the nitrogen concentration of the solution from increasing. From this point of view, it is desirable that the cO2 concentration be low, and it is also desirable that the cO2 concentration be low from the standpoint of preventing oxidative damage to carbon-based refractories, which are commonly used as refractories lining steel vessels.

Conventionally, the processes for recovering high-purity CO gas using the above-mentioned exhaust gas as raw materials include the cryogenic separation method, the liquid preparation method, and the Co50
Solution absorption methods such as the rb method are being considered. However, the former requires low temperature and high pressure, and the latter requires high temperature and high pressure, and both have the drawback that the equipment is complex and expensive. Furthermore, in the cryogenic separation method, it is difficult to completely separate N2 and CO because the centers of H2 and CO are close to each other.

In view of the above-mentioned current situation, the present inventors attempted to develop an adsorption method as a technology to recover high-purity J"l-CO gas at low cost through a simpler process. Propane gas is used as a holding flow in soft tube tuyeres, such as the double tube type Q), which is often used for blowing in a 4゛δ corrosive gas stream consisting of oxygen or at least a gas containing this Yf. However, the propane gas must be purchased in one's own country, which increases the cost.
A study was carried out using progas σ) as an encapsulated gas instead of other σ).

As is well known, carbon oxide is generally used as natural scum, and propane is used in refinery gas and oil-deficient charcoal fires.
After f5, it is combined with steam and CO□ (1 ton), and subjected to a b'G purification and dehydration process using soda, and is currently produced on a single-seedling scale by the cryogenic separation column method.

However, although this method is considered to be optimal for producing high-purity gas for production purposes, it has the disadvantage that it requires low temperature and high pressure, and the liquefaction equipment is expensive. Carbon dioxide acts as an oxidizing gas at high temperatures;
Magnesia, which is usually used as a refractory material around the tuyere.
There is also the disadvantage that the carbon in the carbon bricks and the carbon in the brick joint material are consumed by fire oxidation, which accelerates the wear and tear of the refractories.

In this way, the use of carbon dioxide as a maintenance fluid for soft tube tuyeres is far less economical than one square meter of propane, and has a negative impact on the useful life of a person.

In addition, 0□ gas is blown into the iron bath and is generated in large quantities.
This FeO reacts with the refractory material around the tip of the soft tube lining,
There was a risk that the melting point would be lowered and the refractory would be melted and damaged by the high temperature molten iron, but the reaction of (injection of Ko0 is the following formula (5) % formula %) made Fe0YA1 element, and FeO8 degree in the vicinity -
In addition to being advantageous in terms of F yield, CO is reducing, so
While -CO2 is oxidizing, and (magnesia-carbon-based or magnesia-dolomite-carbon-based bricks σ, which are useful as bottom-resistant materials in bottom-blowing converters) are listed as prior art. This is also advantageous from the viewpoint of deterioration due to μs.

By the way, in order to enhance the tuyere protection effect by utilizing the mechanism for reducing erosion of the L tuyere and its surrounding refractories and the endothermic reaction (formula 4) described above, powdered carbon It is desirable to achieve sufficient precipitation of σ), and the higher the CO concentration in the gas, the more advantageous it is.

However, using a gas with a high CO concentration (for example, pure CO gas) as the encapsulating gas will lead to an increase in cost (σ), which is contrary to the current situation, which calls for cost reduction.

In this respect, CO2 in steelworks is easy to obtain and relatively sensitive.
Blast furnace exhaust gas and converter exhaust gas have, as an example, the following σ) river bottom.

Kazutatsumi -90,N, 1"L Furnace exhaust gas 25.0 20.0 54.0 5.0
0 Converter exhaust gas 66.0 16.0 15.9 2Ll
It has been revealed that if blast furnace exhaust gas containing relatively multi-vertical αJ2 and N2 such as O,1 is used as it is as encapsulating gas, the following problems will occur.

In other words, when the amount of CO2 is greater than (?0 amount), the precipitation of powdery carbon and the reaction do not occur, and the cooling insulation 61 of the soft tube layer is affected by the single liter of encapsulated gas. Stops at thermal change,
The effect is poor, and N2a in the molten iron at the end of blowing.
As a result, the steel quality will be impaired.

In order to solve the above problem, we have conducted a series of research studies and found that if the carbon dioxide and nitrogen content is 1% or less, the quality of the steel will not be affected. We have repeatedly considered the possibility of separating ash monoxide from the mixed gas using an adsorption method using only I/I.

The above-mentioned adsorption separation using the adsorption method (PSA method) of exhaust gas is well known and was developed in the 5th B.A.
12 items from -25928 to 43-15045? It has been advertised or published in various ways as a basic watch, and it can also be adsorbed to any suction tape! A method of separating the easy-absorbing dust component (YA) according to its purity has also been practiced for a long time, by adsorbing the water scum component (hereinafter referred to as the "easily absorbing layer component") to a stratification agent, depositing it on N9°, and recovering the fraction. For example, there are specific examples of using ethylene as a filler component and its application to nitrogen content 111E.

Traditionally performed inhalation N j'i! in gas mixtures!
1. The method of recovering easily adsorbable components involves the following complicated operations. Adsorption pressurization process - 19 flow process - theory layer process'? : By repeating the process, it is possible to extract 11 times the gas mixed with the easily adsorbed component to the adsorbent.

However, is it co-adsorbed like the LIR gas this time? It has not been carried out to remove carbon dioxide and carbon dioxide from a mixed gas containing carbon dioxide and convert it to carbon monoxide at a commercial concentration. do not have.

11 people who did not come out first had N2 and α)2 or N2, CO2
One application was filed for a method for removing N2 from a mixture of CO and 1 by the PSA method (Japanese Patent Application No. 57-15).
(See No. 9211). When carbon monoxide is concentrated from the mixed gas in the previous application No. 57-159211, nitrogen is removed and hydrogen and oxygen are completely removed, but when carbon monoxide and carbon dioxide coexist, they are adsorbed in the same way. Because of the concentration, it was not possible to sufficiently raise the temperature of -carbon oxide to 0 degrees. As a result of various studies, it was found that it was possible to easily and economically perform the separation of high-concentration carbon monoxide by using a carbon dioxide removal technology using adsorption as a pretreatment process. .

The present invention mainly uses carbon dioxide,
- In a method for condensing carbon monoxide in a raw material gas consisting of carbon oxide and nitrogen, (al) the adsorption operation in the m1 stage is performed by filling an adsorbent material with selectivity to carbon dioxide: y: two or more The method consists of removing carbon dioxide from the feed gas by repeated pressure fluctuation adsorption separation in each adsorption column, with adsorption and delayering.
(hereinafter referred to as de-CO2I) SA method (・u) and (b) The second stage adsorption operation is the monoxide in the gas discharged from the first stage adsorption process (hereinafter referred to as the first stage gas). Two or more adsorption towers filled with an adsorbent material having selectivity for carbon are used, and the method includes: (11) a pressurizing step of pressurizing the adsorption towers with a first stage head gas; The product gas of the first step is passed through an adsorption tower,
The adsorbent is allowed to adsorb the easily adsorbed component until the 0 degree of the easily adsorbed component at the outlet of the adsorption tower reaches the point of the easily adsorbed component at the inlet of the adsorption tower, or slightly before the point where the concentrations of both become equal. , 611) Adsorption (After the completion of the Il step, the upper adsorption tower and the adsorption tower where vacuum desorption has been completed are connected, and the gas is introduced from the former adsorption tower to the latter adsorption tower, and the pressure of the 611 adsorption tower is increased. A depressurized discharge process in which the pressure is lowered to atmospheric pressure or near atmospheric pressure, purge process in which the product gas is introduced in parallel flow into the depressurized adsorption tower to purge difficult-to-adsorb components, tV) The number of M components adsorbed by the adsorbent is A recovery process in which the product gas is recovered by desorption using a vacuum pump, and an adsorption tower with σ) gas from the latter adsorption tower by connecting the adsorption tower where product recovery has been completed and the adsorption tower where the adsorption process has been completed.
11) Step (hereinafter referred to as N2-de-PSA method), the method is characterized in that the above operation is repeated in all the adsorption towers by periodically changing the fl flow between the adsorption towers.

The present invention will be explained in detail below.

The main components of the present invention are carbon monoxide, carbon dioxide, nitrogen,
Carbon monoxide is condensed and fractionated from a raw material gas consisting of hydrogen and oxygen by a pressure fluctuation type adsorption separation method (in the UH-r method, two or more absorbers containing a zeolite-based absorbent are used). Use an adsorption tower.

The step of removing the carbon dioxide lf from the raw material gas in the first stage may be carried out by repeating adsorption using a normal PSA method, depressurization, purging with product gas, and pressurization with product gas, or may be carried out by other methods. It may be. A preferred method of removing carbon dioxide is as follows.

Filled with adsorbent material that is selective to carbon dioxide 1
If two or more adsorption towers are used, the method is preferably a pressurizing step of pressurizing the adsorption tower with the product gas of the 11th pestle in the circulation direction, preferably 1 to 6 to 9/a.
(11) Adsorption step in which carbon dioxide is mainly adsorbed on the adsorbent material by flowing the raw material gas into an adsorption tower, +**++ Preferably, in the recirculation direction, the pressure is reduced to around the atmospheric pressure mark of the foil suction Y. In the depressurization step, the exhaust gas is preferably exhausted by the adsorption tower pump in the direction (>1), (preferably F
Ruta 7. JJf Ki is 60~5 U (] 'I'or
r +) and (Vl preferably following the circulation direction) the situation t'J2P
The S A device consists of the upper part of the purge, using the scrap gas from I4' and σ) without vacuum evacuation, and changing the flow between the several layer columns at a constant (υ). , a method consisting of returning green to all the adsorption towers and the above operations.

The second stage adsorption operation involves two or more adsorption systems filled with nitrogen-absorbing substances that are selective to carbon monoxide in the gas discharged from the first stage adsorption process (hereinafter referred to as the first stage product gas). The method using a column is (1) Pressurization step of pressurizing the adsorption column 7 with the raw material gas.Furthermore, the raw material gas is passed to the YM deposition column, and the concentration of the easily adsorbed component at the outlet of the adsorption tower is reduced to the concentration of the easily adsorbed component at the inlet of the 2H column. An adsorption step in which the easily adsorbable component is adsorbed on the adsorbent until the temperature reaches 10 degrees or a little before the point where both degrees are equal; (i+i) After the adsorption step,
In adsorption (II), the adsorption tower is connected to the adsorption tower that has completed desorption, and the gas from the former adsorption tower is exclusively transferred to the latter adsorption tower to be adsorbed onto the latter adsorbent. The pressure χ is lowered to near atmospheric pressure, and the product gas is introduced in parallel flow into the depressurized suction R tower.
Purge step to purge the C-adsorbed components.

(V) Sucking! A recovery process in which the easily adsorbed components adsorbed on the 3ill are desorbed using a vacuum pump and the product gas is recovered; The process consists of a pressurization process using gas from the adsorption tower (adsorption II), and the flow between the adsorption towers is changed periodically, and the above operation Y M+ is carried out in all the adsorption towers.
[Co., Ltd.] 1-This is a characteristic and relates to a method.

Step (1) in the second step of the present invention is a step of pressurizing the adsorption tower by introducing the raw material gas into the adsorption tower.In the present invention, the gas to be recovered is an easily adsorbed component, so a high adsorption pressure is not necessary. An adsorption pressure of about 1k17/ff1G is sufficient, and a lower adsorption pressure may also be used.

Step (11) is an adsorption (r) step, which is the point at which the concentration of easily adsorbed components (-carbon oxide gas, carbon dioxide gas) at the outlet of the adsorption tower becomes equal to re 11 of the easily adsorbed components at the inlet of the adsorption tower. Taste the breakthrough point of the adsorbent.

If the component to be recovered is an adsorbed component (for example, oxygen gas in the case of separating oxygen gas from air),
In order to obtain explosively adsorbed components of high purity, it is desirable to complete the adsorption process at a water content above the breakthrough point. However, in the present invention, since the component to be recovered is an easily adsorbed component, adsorption is carried out until the breakthrough point or just before the breakthrough point is reached.

In the step t++**, the adsorption tower that has undergone the adsorption ([) process and the adsorption tower that has undergone the vacuum desorption process are connected, preferably in a parallel flow direction, to introduce gas from the former adsorption tower into the latter adsorption tower. The pressure in the adsorption tower is reduced to atmospheric pressure or near atmospheric pressure.

In this process, the gas between the walls between the adsorbents housed in the adsorption tower is released, and the adsorption (...
Used for pressurization. This operation is maintained until the pressure in the former adsorption tower reaches approximately atmospheric pressure.

%■ Introducing the product gas in parallel flow into the reduced pressure adsorption tower to purge the remaining difficult-to-adsorb components (degraded element gas, etc.) in the adsorption tower internal pressure. In this case, it is preferable that the introduction pressure of the component gas be lower than the adsorption pressure and higher than the atmospheric pressure. In step (V), the adsorption tower after the purge step is evacuated to preferably 60 to 60'rorr using a vacuum pump, and the components (-carbon oxide gas, etc.) adsorbed on the adsorbent are removed.
is desorbed and recovered as product gas.

Step (Vl) connects the adsorption tower where product recovery has been completed and the adsorption tower where the adsorption step has been completed, and the former adsorption tower is pressurized and adsorbed with the gas from the latter adsorption tower. Adsorption (11) In this case, the latter When the adsorption tower reaches g atmospheric pressure, the supply of gas stops, so the pressure in the adsorption tower does not reach atmospheric pressure.

Hereinafter, the present invention will be described in detail based on a method of removing nitrogen gas in converter JJF gas and separating and recovering -M carbon, which is a typical example of the FX invention. It is not limited to one specific row of these.

FIG. 1 is a flow sheet in which carbon dioxide and nitrogen X are continuously removed from converter exhaust gas by an adsorption method, and carbon oxide residue is separated and condensed.

Adsorption towers A and B house adsorbents that selectively adsorb carbon dioxide. The adsorption towers A and 13 are evacuated to a reduced pressure of 1υOTorr, preferably 60”Corr, using a vacuum pump.
It is done until r, and now the purification tower AKKA feed gas is pressurized and introduced.
A Open valve 1 to draw pressure from the empty state. At this time, all valves except valve 1 are idle! It has become a county.

At this step, the adsorption z5B is still Jc'g! , holds the state. Adsorption tower A has an adsorption pressure of 0.01 after external pressure.
kg/cd a to 3.0X//ff1G, preferably 0.2 Yu/+ff1G to Tokyo/=G, valve 2 is opened and carbon dioxide, carbon monoxide, and other gases containing gas are also released. Part is adsorbed on the adsorbent, and the rest is discharged from the end of the adsorption column (7). After completion of the adsorption process for a certain period of time or a certain amount, the raw material supply valve 1 and the outlet valve 2 are closed, and the valve 6 is opened to reduce the internal pressure of the adsorption tower A to near atmospheric pressure. When the pressure to the adsorption tower approaches atmospheric pressure, valve 6
is closed, and the nozzle 4 is opened from the bottom 9B of the adsorption tower, and the vacuum pump is used to perform depressurization and exhaust, and the adsorbent absorbs ML7'''C.
Desorbs the carbon dioxide component present. The exhaust pressure at this time is 1001'orr, preferably 601'orr. When the decompression #1' is completed, a life-saving lesson r1 will occur. ) By using the waste gas Z from the dead N2PSA casing, the adsorbed carbon dioxide 7 is adsorbed without being completely desorbed from the adsorbent.
From 1l, J14 comes out 1-0 to this nitrogen ↑ J1- air and purge gas are combined in one company, and the odor exhaust pressure is 2701'c+r
It becomes r. 4. When the Qi purge ends, valve 4
Then, valve 5 is closed and valve 6 is opened &↑ to pressurize the 1VK deposition tower to the adsorption pressure with the product gas.

, 1:01: Operation 1- The operation is repeated sequentially in each adsorption tower to continuously adsorb and remove C()2 in the adsorption tower 1j. IT general! ￥
Q') P S A device removes carbon dioxide and removes nitrogen in two stages σ) P S A 'Lklt...
21) SA device, 'f;! : Motte hydrogen "rl?R" is removed from the silk and carbon monoxide is removed from the carbon monoxide (1f1 "χ high fζ)l" to separate it.
r):)' is the number of N components (in this case, - dicarbonized carbon and diIRized carbon A). Cloth bottle (,,: D E F
The lack of vacuum is 41 games and the pressure is 1 air x 1 (l
O'I? orr, preferably up to 60 Torr, and the raw material gas (from which carbon dioxide has been removed in the first stage PEA apparatus) is now introduced under pressure into the adsorption tower C. Vacuum state of recycled cylinder! This is done by opening 16 pieces of K pulp to increase the pressure. The pressure increase rate at this time is adjusted by the vanobutton 15. After increasing the pressure, the pulp 17° 18 is opened and at the same time the valve 16 is closed and the mixed gas passes through the adsorption tower. At this time, the easily adsorbed components 1+'f carbon and 21 carbon are adsorbed by the adsorbing gas, and other gases pass through the adsorption tower and are partially desorbed by Gi (used as purge gas for the PSA device). 11 will be sent.

Since the leakage still contains a considerable amount of hydrogen and hydrogenated carbon, it is recovered in the evening at 46 in order to be reused as fuel gas or the like.

Raw material supply valve 1 after adsorption for a certain period of time or for a certain amount of one rod
B and outlet valve 17 are closed, valve 19 in the connecting pipe to the adsorption tower is opened, the internal pressure of adsorption tower C is reduced to near atmospheric pressure, and the adsorbent in N absorption tower 1 is depressurized and released. Allow the gas to be absorbed. When the pressure in the adsorption tower C approaches atmospheric pressure, the valve 20 is opened from the product gas tank 42 to expel the gas that is difficult to adsorb in the nitrogen Vφ (space between adsorbents) inside the adsorption tower. From 143 onwards, purge will be carried out on the 18th.

When the purge step is completed, valves 19 and 20 are closed, valve 21 is opened from the bottom of the adsorption tower, and the Makabe pump is used to perform vacuum evacuation to desorb easily adsorbed components adsorbed on the adsorbent. At this time, 4 no. 1 atm pressure &1100'L'o
It is preferably carried out to 60'T'orr and recovered as C1-pM gas which is an easily adsorbed component.

In each of the above-mentioned adsorption towers, CO gas, which is an easily adsorbed component, can be adsorbed continuously onto the adsorbent 14 to produce a separated Iff. Note that 46 is a depressed gas tank.

As mentioned above, by combining the -yith floor σ) decomposition ('02 PSA device and the second stage deN2P PSA device t), the deN2P PSA device alone can remove carbon monoxide from one sardine to 1a, and produce a It was possible to significantly reduce the concentration of CO2 compared to when it was done, and it was also possible to remove CO
By using the waste gas from the N2 PSA device h' as the purge gas for the 002 PSA device, it is possible to improve the recovery rate of carbon monoxide compared to when it is used in the product waste purge process of the 002 PSA device. According to the present invention (X
)2 can be reduced to 0.5'fl and N2 can be reduced to 1qb or less.

Example 1 Below, in order to explain the present invention more specifically, converter exhaust gas (CO = 854 CO□ = 2.7 coefficient N2 = 4.9 11
□ = 96% 02 = 0.1%) 1 attempt at making amber.

Already mentioned as 4'+W manufacturing process! jl+ < In the first stage, [adsorption-depressurization, depressurization-exhaust-) product processing] in the de-C02 PSA equipment and in the second stage, in the de-N2 PSA equipment K.
Original $1 Pressurization - Adsorption ([(-Decompression suction Jf (If) -Noku-
The purification was carried out based on the purification cycle of 1111-white air evacuation-pressurization.

The first stage CO□PSA device contains activated zeo/%-
The activated Zeo I-bu (166Ky 1/8"
A single steel adsorption tower (16B x 2Am
) Father vacuum pumping 100 Torr and 601. After applying 4' to each 'orr, the above mixed gas χ linear velocity Ocm /
SeC was introduced from the bottom of the column to carry out nitrification of the mixed gas.

For supply gas F, t't-32,8nfK, 1st T-made carbon oxide carbonaceous acid is 19 filtration If-, at this time σ) De-N2PS
The amount of waste gas in A device 6 was 16.5 doors, and the recovery rate of carbon monoxide was 68%.

The gas composition after purification was as follows.

Gas composition CO = 98.6 coefficient C02 = 0.5% N2 = 0.9qh 11□ = (] coefficient J, )2 = [J coefficient Example 2゜The following experiment was carried out using the same apparatus 7 as in Example (1). Converter 1 under conditions
This is the result of 1 column and separation using 7 gases.

Experimental conditions Gas, 1 C0 = 86'k (, l'U2 = 4%N
2-4% II, = 6 operating temperature 25℃ adsorbent ZE-5
01 Suction layer velocity, 6.5 cR/sec Suction pressure 1. [J
kg/lya, G Makabe, 1st atmosphere, 100 Torr and 60 Torr, and the product gas was concentrated and purified with fecalized carbon.

The amount of supplied waste was 42.9171', the amount of silk-melted carbon gas was 25.7 m', and the recovery rate of carbon monoxide was 68.64.
And one.

The gas composition after distillation is (, '0 = 98.7 section GO2 = 0.5’l N2 = 0.8 section Example 6゜ An attempt was made to produce TQ from converter exhaust gas.

The purification process is as described above (in the first stage, CO2 removal equipment "adsorption-depressurization-vacuum exhaust - product processing") and in the second stage, the second stage is the [first stage product gas pressurization] of N2 deN2 PSA@+-. adsorption(
I) - Decompression skewer pressure relief - Discharge - True nitrogen exhaust - Decompression -
The test was carried out based on the 114 cycle manufactured by Suction Co., Ltd.

The first stage de-CO2PSA device angle contains activated zeo/
A steel adsorption tower (12"Xl, 7m) filled with 1-pu (50 ky 1/16" pellets) and an activated ZeoHarp (166 ky 1/8") second stage deN2 device. pellet) on top and activated alumina (30 ml, Sumitomo KHD-
A steel adsorption tower (16B x 2.4
m) was used.

Experimental conditions〉 Converter exhaust gas composition: Co = 86 coefficient C02 = 6 width N2 = 4 width N2 = 7 width Operating temperature: 60°C Adsorption pressure 1. Okl? /crIIG vacuum evacuation: de-CU2PSA~120 Torr de-N2P SA~80
Torr supply gas amount is 30.21Tl', 4'+V Co gas meter is 13.5m'' and CO gas recovery rate is 51.584
Met. The gas composition after purification at this time was CO=99.
0 coefficient C02 = 0.3% N2 = 0.7 Example 4 Using the same setting as Example 6, one experiment was conducted using converter exhaust gas under the following formula 1 central experimental condition. 〉 Converter exhaust gas composition: CO = 85 coefficient CO2 = 5% N2 = 5% Port 2 = = 7If + Operating temperature = 65°C Adsorption pressure 2 0.5 kW/cd (3 Vacuum exhaust: CO2P SA ~ 120 Torr DeN2
P S A ~ 80 Torr Purified CO gas amount is 15 for supply gas bone 56.2rn+
At 3111', the CO gas recovery rate was 494, and the gas production rate of Kozue Seisha was co=qq, 4%cO2fJ, 4th section N2
=0.24b

[Brief explanation of drawings]

The figure is a flow sheet showing a preferred embodiment 7 for carrying out the present invention. Special 1m0RGO-78813 (8) Procedural Amendment November 30, 1920 d8-4; Interpretation t I L1↑ 1. ? -1 Drawing board Kum I skin (1 inferior °t・self/sills) so δ lever, wave, i + t゛ J comment = 1.6, relationship with the case of the person making the amendment Address of the patent applicant f? R,,?, (lZr) JIIJ, now'lL4
't-1''!, to 8〈NINOJ/DAT+G) 4. Written amendment to the attorney's procedure Date of January 1987, Kazuo Wakasugi, Commissioner of the Japan Patent Office 1. Indication of the case No. 187480 No. 2, Name of the invention: A method for purifying carbon monoxide from a mixed gas containing carbon monoxide using an adsorption method, and its relationship to the case of the person making the amendment Patent applicant address and name (125) Kawasaki Steel Corporation Stock Company (1 other person) 4. [Claims] and [Detailed Description of the Invention] columns of the agent's specification (attachment) (1) The scope of claims is corrected as follows: "( 1) A method for concentrating carbon monoxide in a raw material gas containing at least carbon dioxide, -carbon oxide, and nitrogen by a two-stage adsorption operation, in which (a) the J-stage adsorption operation is selective to carbon dioxide; using two or more adsorption towers filled with an adsorbent material having an adsorption material having the following properties: (b) The second stage adsorption operation is carried out using an adsorption material packed with an adsorbent material that is selective to carbon monoxide in the gas discharged from the first stage adsorption process (hereinafter referred to as the first stage product gas). The method uses two or more adsorption towers, and the method includes (i) pressurizing the adsorption tower with the first stage product gas; (11) further flowing the first stage product gas through the adsorption tower to facilitate easy flow at the outlet of the adsorption tower; Adsorption (I) of adsorbent 1 (adsorption (I) process for adsorbing easily adsorbed components, track) until the concentration of the adsorbed component reaches the concentration of the easily adsorbed component at the inlet of the adsorption tower, or slightly before the point where both concentrations become equal. ) After the completion of the process, the adsorption tower is connected to the adsorption tower that has undergone vacuum desorption, and the gas is introduced from the former adsorption tower to the latter adsorption tower to reduce the pressure in the former adsorption tower, ( 1v) A purge step in which the second-stage product gas is introduced into the reduced pressure adsorption tower to purge the components that are difficult to adsorb; A recovery step in which adsorbed components are desorbed and product gas is recovered, and (vl) the adsorption tower in which the product gas recovery has been completed is connected to the adsorption tower in which the adsorption (I) step has been completed, and the gas from the latter adsorption tower is transferred to the former. A method characterized by repeating the above operation by periodically changing the flow between the adsorption towers. (2) The first stage adsorption operation is ( 1) Pressurization step of pressurizing the adsorption tower with the first stage preparation gas, adsorption step of flowing the raw material gas into the adsorption tower and mainly adsorbing carbon dioxide onto the adsorbent material, (i+r) then reducing the adsorption pressure to near atmospheric pressure Decompression 1
(1) Next, it consists of an evacuation process in which the adsorption tower is evacuated by a vacuum pump, etc., and (M) a purge process that uses the waste gas from the second stage, and the flow between the adsorption towers is changed periodically, and the above The method according to claim 1, which comprises repeating the operation.'' (2) All lines from page 4, line 2 to page 10, line 4 of the specification are corrected as follows. A method for obtaining high-purity carbon monoxide from converter or blast furnace exhaust gas, mainly raw material gas containing carbon monoxide, carbon dioxide, and nitrogen, by the PSA method (PSA method). The exhaust gas generated from the refining vessel contains a relatively large amount of CO gas.The composition is within the range 1/U shown below for converter exhaust gas and blast furnace exhaust gas. 60-87% 6-20% 6-20%1
~ Section 10 Blast furnace exhaust gas 20 ~ 0% 20 ~ 60 Section 40 ~
60 coefficients 1 to 10 coefficients, high-purity C can be extracted from these exhaust gases.
If O gas can be recovered safely, it can be used as a raw material for synthetic chemicals,
It can be used as a gas to be blown into the straight metal inside the refining vessel. When considering the raw material for synthesis and this CO gas,
Since the synthesis reaction is usually carried out under high pressure conditions of 6%, it is essential to remove oxidizing gases that can damage the reaction vessel, and it is necessary to reduce the CO2 concentration as much as possible, as well as to reduce the reaction efficiency. In order to increase the reaction rate, it is desirable to remove as much N2 as possible, which normally does not participate in the reaction. On the other hand, gas injection into a refining vessel is widely carried out for the purpose of improving the efficiency of refining molten metal. Expensive Ar gas is usually used, but if high purity COO20 can be recovered at low cost from converter gas and blast furnace gas, which are generated in large quantities in steel plants, it is possible to replace this with Ar. . At this time, high purity COO20N
2. The concentration is desirably low from the perspective of preventing an increase in the nitrogen concentration of molten iron, and the CO2 concentration is also desirably low from the perspective of preventing oxidation damage to carbon-based refractories, which are commonly used as refractory linings for refining vessels. As a process for recovering high-purity COO20 from exhaust gas as a raw material, a cryogenic separation method, a liquid preparation method, and a solution absorption method such as the Co5orb method are considered. However, the former requires low temperature and high pressure, and the latter requires high temperature and high pressure, and both have the drawback that the equipment is complicated and expensive. Furthermore, in the cryogenic separation method, since the boiling points of N2 and CO are close to each other, it is difficult to completely separate N2 and CO. In view of the above-mentioned current situation, the present inventors attempted to develop an adsorption method as a technique for recovering high-purity COO20 at low cost through a simpler process. The above-mentioned adsorption separation using the adsorption method (PSA method) of exhaust gas is well known, and was developed in 1973 for the purpose of recovering gases that are difficult to adsorb to adsorbents (hereinafter referred to as difficult-to-adsorb components).
-23928.43-15045 etc. have been published as basic patents.'' (3) All of the specifications from page 11, line 13 to page 13, line 10 are corrected as follows. "The present invention provides a method for concentrating carbon monoxide in a raw material gas containing at least carbon dioxide, carbon oxide, and nitrogen by a two-stage adsorption operation. The method uses two or more adsorption towers filled with an adsorbent material that is selective to (b) The second stage adsorption operation is an adsorption process that is selective to carbon monoxide in the gas discharged from the first stage adsorption process (hereinafter referred to as the first stage part gas). Two or more adsorption towers filled with substances are used, and the method consists of (1) pressurizing the adsorption tower with the first stage part gas; (11) further flowing the first stage part gas into the adsorption tower; hand,
an adsorption (I) step in which the adsorbent adsorbs the easily adsorbable component until the concentration of the easily adsorbable component at the outlet of the adsorption tower reaches the concentration of the easily adsorbable component at the inlet of the adsorption tower, or until a little before the point where both concentrations become equal; ) After the adsorption (I) step, the adsorption tower is connected to the adsorption tower that has undergone vacuum desorption, and gas is introduced from the former adsorption tower into the latter adsorption tower to reduce the pressure in the former adsorption tower. Pressure step (1) Purge step of introducing the second stage component gas into the reduced pressure l-adsorption tower to purge the difficult-to-adsorb components, (
V) A recovery step in which the adsorption tower that has completed the purge step is evacuated to below atmospheric pressure to desorb easily adsorbed components adsorbed by the adsorbent and product gas is recovered; and (vi) adsorption after product gas recovery has been completed. The adsorption tower is connected to the adsorption tower that has completed the adsorption (1) step, and the gas from the latter adsorption tower is introduced into the former adsorption tower.The flow between the adsorption towers is periodically changed. The present invention relates to a method characterized in that the above operations are repeated. (4) Delete all lines from page 15, line 2 to page 16, line 7 of the specification. (5) All lines 1 to 2 of page 18 of the specification are ii'l below.
'ilE. In step (v), the adsorption tower after the purge step is evacuated to below atmospheric pressure using a vacuum pump, ejector, blower, etc., preferably below 300 Torr, most preferably in the range of 50 D = 3 D Torr. (5) The specification is amended as follows. Page Line Before correction After correction 1315 Zeolite adsorption Zeolite (natural or synthetic) adsorption agent 14 6 1st process 1st stage 1414 Pump, etc. Page 14, line 20 ~ All adsorption towers <Deleted> Page 15 J line
In 16 8 2nd process 2nd stage 36 8-9 Raw material 1st stage preparation 1611 1kg 1-31 (g 16 J5 Carbon dioxide gas deleted> 1714 Parallel flow deleted> 1714 Product 2nd stage parts 18 5 Product Recovery Product gas recovery 187-8 Adsorption process Adsorption (I) process 187-8 Adsorption (l) Adsorption (I) process. Page Line Before correction After correction 19 1-2 100 Torr preferred 300 Torr or less, preferably 60 Torr L < Haro0Torr19
19-20 20 13, PSA De-Co2 PSA20 15 P
SA device <Delete> 21, 1 100 Torr preferred 300 Torr or less preferably 60 Torr I, <30 Torr21
At the end, when the pressure reaches near atmospheric pressure, close the and valve 19 in the adsorption tower, open the valve 20 in the adsorption tower, and open the valve 20 in the adsorption tower.
Furthermore, valve J7 is opened and adsorption tower C is opened.
312 Product processing Product pressurization 2312-13 Raw material pressurization 1st stage component gas pressurization 2313 Purge adsorption q11) Purge 24 13 D
,, 0□ Page Line Before correction After correction 2512 1st stage 1st stage 2513 Product processing Product pressurization 2514 2nd stage 2nd stage 2518 1st stage 1st stage 25 End 2nd stage 2nd stage

Claims (1)

[Claims] (1) By a two-stage adsorption operation, at least carbon dioxide,
- In a method for concentrating carbon monoxide in a raw material gas containing carbon oxide and nitrogen, (a) the first stage adsorption operation is performed using two or more adsorption systems filled with an adsorbent material having a selectivity of 2 for carbon dioxide; the process consists of repeating adsorption and desorption in each adsorption tower and removing carbon dioxide from the feed gas by pressure-fluctuation adsorption separation; and (b) a second stage of Sucking; 9! The f operation involves the use of two or more adsorption towers filled with an adsorbent material that exhibits selectivity for carbon monoxide in the gas discharged from the first step adsorption step (hereinafter referred to as the first step product gas). The method is 1i) Pressurizing step of pressurizing the adsorption tower with the 1st step product gas (11) Furthermore, flowing the ml 8M product gas into the adsorption tower,
Adsorption (1) step of adsorbing the easily adsorbable component onto the adsorbent until the concentration of the easily adsorbable component at the outlet of the adsorption tower reaches the concentration of the easily adsorbable component at the inlet of the adsorption tower, or until just before the point where both concentrations become equal; After the adsorption (I) step is completed, the adsorption tower is connected to the adsorption tower where the odor desorption has been completed, and the gas is introduced from the former σ) 1-ku gradual tower to the latter adsorption tower, and the 1511 adsorption tower is σ) Depressurization and release process to lower the pressure, Mosquito) Purge process to purge difficult-to-adsorb components into the depressurized adsorption tower in parallel flow with the product gas of the second process, M: Easy-to-adsorb components adsorbed by the adsorbent at ℃ A recovery step in which the product gas is desorbed and recovered using a vacuum pump, and an adsorption tower in which the product gas recovery has been completed is connected to an adsorption tower in which the adsorption step has been completed, and the gas from the latter adsorption tower is The adsorption bending process consists of the ~ID adsorption 9111 process using gas from the purge process of other adsorption towers, and the above operation is repeated in all adsorption towers by periodically changing the flow between the adsorption towers. (2) The adsorption operation in the first stage is as follows: (11) A pressurizing step in which the adsorption tower is pressurized with a soft 1-step island-forming gas; The adsorption step of adsorbing the useful carbon onto an adsorbent material (beating, then adsorption
The process consists of a depressurization process in which the pressure is reduced to around atmospheric pressure, an exhaust process in which the adsorption tower is evacuated by a vacuum chamber, and a purge process that uses the waste beam gas from the second process. 2. A method as claimed in claim 1, comprising repeating the above operation in all adsorption towers by changing the flow between the busy adsorption towers.