JP2008207172A - Production method of oxygen enriched air and production device thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a production method and production device capable of stably producing an oxygen enriched air for a long period of time without being influenced by moisture in the air when the oxygen enriched air is produced from the air by utilizing an adsorber for adsorbing nitrogen such as a zeolite. <P>SOLUTION: Adsorbers for adsorbing moisture 3, 4, interposing an adsorber for adsorbing nitrogen 2 the adsorbed amount of which increases in accordance with the increase of pressure, are arranged on both sides thereof, the adsorbers are rotated around axial centers thereof, and airs with different pressures are supplied to the adsorbers from the opposite directions, respectively. The airs are passed through the adsorber for adsorbing moisture, the adsorber for adsorbing nitrogen and the adsorber for adsorbing moisture in sequence, the air with relatively increased pressure is subjected to a dehydration treatment, a denitrification treatment, and a moisture enrichment treatment in sequence, and the air with the relatively decreased pressure is subjected to a dehydration treatment, a nitrogen enrichment treatment, and a moisture oxygen enrichment treatment in sequence, thereby enriching oxygen in the air with relatively increased pressure. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method and apparatus for producing oxygen-enriched air from air by removing nitrogen components in the air.

  The air that is blown into a blast furnace that produces hot metal from iron ore, an incinerator or melting furnace for waste, and a furnace for slabs is oxygen-enriched air with an increased oxygen concentration to increase combustion efficiency. Is often blown. A conventional method for producing oxygen-enriched air is to produce nearly 100% high-purity oxygen (referred to as “pure oxygen”) from air by a cryogenic separation method, a PSA method, etc., and then mix this with air. Dilution has produced oxygen-enriched air with the desired oxygen concentration. However, in the method of producing pure oxygen by using the cryogenic separation method and the PSA method and diluting the pure oxygen with air to produce oxygen-enriched air, a large amount of power is required when producing pure oxygen, Despite the low oxygen concentration of the oxygen-enriched air used, a large amount of power was required as a result.

  In order to solve this problem, Patent Document 1 utilizes the nitrogen absorption ability of zeolite in which a cylindrical container is filled with zeolite, which is an adsorbent for nitrogen absorption, and the amount of nitrogen adsorbed increases as the temperature decreases. Then, the center of the cylindrical container is rotated as an axis, and two airs having different temperatures are independently supplied to the rotating cylindrical container, and the nitrogen of the lower temperature air is absorbed by the zeolite and absorbed. A technique has been proposed in which oxygen is enriched in air at a lower temperature side by releasing nitrogen into the air at a higher temperature side and performing this continuously.

According to Patent Document 1, since nitrogen is not saturated in the zeolite by flowing high temperature air through the zeolite, it can be operated continuously for a long period of time, and in the production of oxygen-enriched air, the power is greatly reduced. Is going to be possible.
JP 2001-70736 A

  However, Patent Document 1 has the following problems.

  That is, zeolite is a powerful adsorbent for absorbing nitrogen, but is also a moisture adsorbent. Therefore, when air is passed through a cylindrical container filled with zeolite, nitrogen is absorbed while absorbing moisture in the air. Unless the absorbed moisture is efficiently released from the zeolite, the absorbed capacity of the zeolite is reduced by the absorbed moisture, and the zeolite functions not only as a moisture absorbing adsorbent but also as a nitrogen absorbing adsorbent. Disappear.

  In Patent Document 1, two airs having different temperatures are independently supplied to a cylindrical container filled with zeolite, but these two airs are not subjected to dehydration treatment, and the temperatures are different. The moisture concentration is basically the same, therefore, the action of removing moisture from the zeolite does not work, the zeolite continues to absorb moisture, and eventually the function as a moisture absorbing adsorbent and a nitrogen absorbing adsorbent stops. . That is, Patent Document 1 has a problem that oxygen-enriched air cannot be produced over a long period of time due to the fact that zeolite absorbs moisture.

  Conventionally, air is used as a raw material when producing almost 100% concentration of pure oxygen by a cryogenic separation method, a PSA method, etc. If a large amount of oxygen-enriched air can be produced at a low cost, For example, using oxygen-enriched air as a raw material is totally efficient even when pure oxygen is produced by a cryogenic separation method, a PSA method, or the like.

  The present invention has been made in view of the above circumstances. The object of the present invention is to supply oxygen as a combustion gas from air to a blast furnace or a heating furnace using an adsorbent for nitrogen absorption such as zeolite. In producing oxygen-enriched air for producing enriched air or pure oxygen, oxygen-enriched air can be produced stably over a long period of time without being affected by moisture in the air. It is to provide a method for producing oxygen-enriched air.

  The method for producing oxygen-enriched air according to the first aspect of the present invention for solving the above-described problem is characterized in that a nitrogen-absorbing adsorbent whose amount of nitrogen adsorption increases with an increase in pressure is sandwiched between each side for moisture absorption. Adsorbents are arranged, and these adsorbents are rotated around their axes, and air with different pressures is supplied to these adsorbents from opposite directions to absorb these air for moisture absorption. Agent, nitrogen absorbent adsorbent, moisture absorbent adsorbent in this order, and relatively high-pressure air is processed in the order of dehydration treatment, denitrogenation treatment, moisture enrichment treatment, It is characterized by performing oxygen dehydration treatment, nitrogen enrichment treatment, moisture enrichment treatment in this order on the air whose pressure has been lowered, and oxygen enrichment of air at a relatively high pressure.

  The method for producing oxygen-enriched air according to the second aspect of the present invention has a nitrogen absorbing adsorbent whose nitrogen adsorbing amount increases with a decrease in temperature, and a water absorbing adsorbent is disposed on each side of the nitrogen absorbing adsorbent. The adsorbent is rotated about its axis, and air having different temperatures is supplied to the adsorbents from opposite directions, and the air is adsorbed for moisture absorption and adsorbent for nitrogen absorption. Then, the moisture absorption adsorbent is passed through in order, and the relatively low temperature air is processed in the order of dehydration treatment, denitrification treatment, and moisture enrichment treatment, and the relatively high temperature air is treated. Thus, the treatment is performed in the order of dehydration treatment, nitrogen enrichment treatment, and moisture enrichment treatment, and oxygen enrichment of air at a relatively low temperature is performed.

  According to a third aspect of the present invention, there is provided a method for producing oxygen-enriched air, wherein an adsorbent for moisture absorption is sandwiched between both sides of an adsorbent for absorption of nitrogen that increases in amount of nitrogen adsorption as the pressure increases and temperature decreases. Arrange and rotate these adsorbents around their axes, and adjust the adsorbent from the opposite direction so that the pressure is relatively higher and the temperature is lower than the other. The air having different pressure and temperature is supplied, and the air is passed through the moisture absorbing adsorbent, the nitrogen absorbing adsorbent, and the moisture absorbing adsorbent in this order, so that the pressure is relatively increased and the temperature is lowered. On the other hand, processing is performed in the order of dehydration treatment, denitrogenation treatment, and water enrichment treatment, and in the order of dehydration treatment, nitrogen enrichment treatment, and moisture enrichment treatment for air whose pressure is relatively lowered and temperature is relatively increased. Treated and relatively pressure Is characterized in carrying out the oxygen-enriched air was increased and the temperature low.

  A method for producing oxygen-enriched air according to a fourth aspect of the present invention is the method for producing oxygen-enriched air according to any one of the first to third aspects, wherein the dehydration treatment, the denitrification treatment, and the water enrichment treatment are performed in this order. The oxygen-enriched air is either oxygen-enriched air blown into the blast furnace from the tuyere of the blast furnace side wall, or oxygen-enriched air used as a combustion gas in a heating furnace or a hot air furnace. It is a feature.

  According to a fifth aspect of the present invention, there is provided a method for producing oxygen-enriched air, wherein the oxygen-enriched air produced based on the method for producing oxygen-enriched air according to any one of the first to third aspects is diluted with air. The diluted mixed gas is oxygen-enriched air blown into the blast furnace.

  A method for producing oxygen-enriched air according to a sixth invention is the oxygen-enriched air produced by performing the treatment in the order of the dehydration treatment, denitrification treatment, and water enrichment treatment in the fourth or fifth invention. The oxygen concentration of air is 30 to 35%.

  A method for producing oxygen-enriched air according to a seventh aspect of the present invention is the method for producing oxygen-enriched air according to any one of the first to third aspects, wherein the dehydration treatment, the denitrification treatment, and the water enrichment treatment are performed in this order. The oxygen-enriched air is characterized by being oxygen-enriched air that is a raw material for producing high-purity pure oxygen.

  The method for producing oxygen-enriched air of oxygen-enriched air according to the eighth invention is the oxygen produced by performing the treatment in the order of the dehydration treatment, denitrification treatment, and water enrichment treatment in the seventh invention. The oxygen concentration of the enriched air is 30% or more.

  An apparatus for producing oxygen-enriched air according to a ninth aspect of the present invention is a first cylindrical container that is rotatable about an axis, and an axial direction of the first cylindrical container with the first cylindrical container interposed therebetween. 2nd and 3rd cylindrical containers which are arranged relative to the axis and which are rotatable about an axis, a nitrogen absorbing adsorbent which is arranged in the first cylindrical container, and the second cylinder Moisture absorbent adsorbent disposed in the mold container, moisture absorbent adsorbent disposed in the third cylindrical container, second cylindrical container, first cylindrical container, and third cylindrical mold A first air supply channel for supplying air that passes in the order of the containers, and a third cylindrical container, a first cylindrical container, and a second cylindrical container in the opposite direction. A second air supply passage for supplying air to be supplied, and a second air supply passage for receiving the air supplied by the first air supply passage. An air discharge passage of, is characterized in that and a second air discharge passage for receiving air supplied by said second air supply passage.

  An apparatus for producing oxygen-enriched air according to a tenth aspect of the present invention includes a cylindrical container that is rotatable about an axis, a nitrogen absorbing adsorbent disposed in the cylindrical container, and the nitrogen absorbing adsorbent. A pair of moisture-absorbing adsorbents disposed opposite to the cylindrical container, and a moisture-absorbing adsorbent, a nitrogen-absorbing adsorbent, and moisture absorption from opposite directions with respect to the cylindrical container. An air supply channel for supplying air that passes through the adsorbent in order, and an air discharge channel for receiving the air supplied by the air supply channel and passing through the cylindrical container. It is a feature.

  An apparatus for producing oxygen-enriched air according to an eleventh aspect of the present invention is the ninth or tenth aspect of the present invention, wherein the nitrogen absorbing adsorbent is a nitrogen absorbing adsorbent in which the amount of nitrogen adsorbed increases as the pressure increases. The air supplied from the opposite direction to the nitrogen absorbing adsorbent via the air supply flow path has a different pressure.

  An apparatus for producing oxygen-enriched air according to a twelfth aspect of the present invention is the ninth or tenth aspect of the present invention, wherein the nitrogen-absorbing adsorbent is a nitrogen-absorbing adsorbent in which the amount of nitrogen adsorbed increases as the temperature decreases. The air supplied from the opposite directions to the nitrogen absorbing adsorbent via the air supply flow path has a different temperature.

  According to the present invention, when producing oxygen-enriched air to be supplied to a blast furnace or the like, moisture absorbing adsorbents are arranged on both sides of the nitrogen absorbing adsorbent, and the opposite sides to these adsorbents. Since air is supplied from the direction of the water and adsorbed in the order of moisture absorbing adsorbent, nitrogen absorbing adsorbent, and moisture absorbing adsorbent, the supplied air is first subjected to dehydration treatment, and after moisture is removed. Since it is in contact with the nitrogen absorbing adsorbent, the nitrogen absorbing adsorbent adsorbs nitrogen from the supplied air without being affected by moisture, and releases the absorbed nitrogen into the air supplied from the opposite side. That is, the nitrogen absorbing adsorbent performs adsorption and release of nitrogen continuously over a long period of time without being affected by moisture.

  Further, the moisture absorbing adsorbent comes into contact with air supplied from one side and adsorbs moisture contained in the air, but the air supplied from the opposite side is relatively sandwiched between the nitrogen absorbing adsorbent. The moisture absorbent adsorbent that has already been dehydrated by the other moisture absorbent adsorbent provided in this way is a dry state from which moisture has been removed by rotation of the cylindrical container. Since it comes into contact, the adsorbed moisture is released to the dry air, and the amount of moisture adsorbed in the moisture absorbing adsorbent decreases. That is, since each moisture absorption adsorbent repeatedly performs adsorption and release of moisture, the moisture absorption adsorbent also performs its function continuously over a long period of time.

That is, according to the present invention, oxygen-enriched air can be produced without being affected by moisture in the air, stably for a long period of time, and without requiring a large amount of power, resulting in an industrially beneficial effect. In addition, the generation amount of CO ₂ is reduced, and a beneficial effect is also obtained in the natural environment.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a schematic perspective view of an oxygen-enriched air production apparatus according to the present invention, and FIG. 2 is a first cylindrical container constituting a part of the oxygen-enriched air production apparatus according to the present invention shown in FIG. It is a schematic perspective view of a 2nd cylindrical container, (A) has shown the 1st cylindrical container, (B) has shown the 2nd cylindrical container.

  As shown in FIG. 1, a first cylindrical container 2 that can be rotated by an electric motor (not shown) around an axis 2 a is disposed inside the tube body 13, and the first cylindrical container 2. The second cylindrical container 3 and the third cylindrical container 4 are arranged so as to face each other in the direction of the axis 2a. The second cylindrical container 3 and the third cylindrical container 4 have the same axial direction as the axial center 2a of the first cylindrical container 2, and are driven by an electric motor (not shown) around the axial center 2a. It can be rotated. In this case, the first to third cylindrical containers may be rotated by the same electric motor, or may be rotated by individual electric motors. When rotating with an individual electric motor, the number of rotations may be different. In FIG. 1, the rotational directions are the same, but they may be different.

  As shown in FIG. 2 (A), the inside of the first cylindrical container 2 is partitioned into a plurality by partition plates 8 extending radially from the shaft center 2a. Surrounded by a net (not shown) or the like, the nitrogen absorbing adsorbent 5 is filled. As the nitrogen absorbing adsorbent 5, it is preferable to use zeolite. Zeolite is a crystalline inorganic oxide, specifically, a crystallinity composed of crystalline silicate, crystalline aluminosilicate, crystalline metallosilicate, crystalline aluminophosphate, crystalline metalloaluminophosphate, etc. It is a microporous material. The partition plate 8 also functions as a reinforcing material for ensuring the rigidity of the first cylindrical container 2.

  The internal structure of the second cylindrical container 3 is the same as the internal structure of the first cylindrical container 2 as shown in FIG. Is surrounded by a wire mesh, a net, etc., and is filled with a moisture absorbing adsorbent 6. Although not shown, the internal structure of the third cylindrical container 4 is the same as the internal structure of the second cylindrical container 3, and a moisture absorbing adsorbent 7 is provided at each part partitioned by the partition plate 8. Filled. As the moisture absorbing adsorbent 6 and the moisture absorbing adsorbent 7, a conventional moisture absorbing adsorbent such as silica gel can be used.

  Note that the internal structure of the first cylindrical container 2, the second cylindrical container 3, and the third cylindrical container 4 is replaced with the structure shown in FIG. 2, and is configured with a honeycomb structure as shown in FIG. May be. That is, the honeycomb structure 26 having the surface coated with the nitrogen absorbing adsorbent 5 may be disposed at each portion partitioned by the partition plate 8. In the second cylindrical container 3 and the third cylindrical container 4, moisture absorbing adsorbents 6 and 7 are applied to the surface of the honeycomb structure 26 instead of the nitrogen absorbing adsorbent 5. In order to reduce pressure loss in the nitrogen absorbing adsorbent 5 and the moisture absorbing adsorbents 6 and 7, these adsorbents are applied to the honeycomb structure 26 without filling the inside of the cylindrical container. However, it is difficult to apply the nitrogen absorbing adsorbent 5 and the moisture absorbing adsorbents 6 and 7 thickly on the surface of the honeycomb structure 26, and the shape of the honeycomb structure 26 is required to apply a necessary amount. In some cases, the honeycomb structure 26 may be taken into consideration when the honeycomb structure 26 is adopted. FIG. 3 is a schematic view showing another example of the first cylindrical container of the oxygen-enriched air production apparatus according to the present invention, and (A) is a perspective view of the first cylindrical container 2, B) is an enlarged view of the honeycomb structure 26.

  Inside the tube body 13, a separation plate 14 is installed at a position passing through the center line of the tube body 13 with the first cylindrical container 2, the second cylindrical container 3, and the third cylindrical container 4 interposed therebetween. The separation plate 14 forms two flow paths inside the tube body 13. That is, in FIG. 1, the air supplied to the first air supply channel 9 on the lower left side passes in the order of the second cylindrical container 3, the first cylindrical container 2, and the third cylindrical container 4. And it discharges | emits to the 1st air discharge flow path 11 of the lower right stage. On the other hand, in FIG. 1, the air supplied to the second air supply channel 10 on the upper right side passes through the third cylindrical container 4, the first cylindrical container 2, and the second cylindrical container 3 in this order. Then, the air is discharged to the second air discharge channel 12 on the upper left side.

  In the present invention, it is an essential condition that air flows in the opposite direction. However, the first cylindrical container 2, the second cylindrical container 3, and the third cylindrical container 4 rotate continuously or intermittently about the axis 2a, and therefore, the first air Not all of the air supplied from the supply flow path 9 is discharged from the first air discharge flow path 11. Similarly, all of the air supplied from the second air supply flow path 10 is the second air. The air is not discharged from the discharge channel 12 and a part of the air is mixed with each other. However, in the present invention, the mixing of the part of the air is not a problem.

  A pipe (not shown) is connected to each of the first air supply channel 9, the second air supply channel 10, the first air discharge channel 11 and the second air discharge channel 12. The air is supplied to the first air supply flow path 9 and the second air supply flow path 10 through these pipes, and the first air discharge flow path 11 and the second air supply flow path 10 through these pipes. The air discharged from the air discharge channel 12 is guided to a predetermined place.

  In this way, the oxygen-enriched air production apparatus 1 according to the present invention is configured. Using this oxygen-enriched air production apparatus 1, oxygen-enriched air is produced from air as follows.

  First, the nitrogen adsorption ability of the zeolite used as the nitrogen absorbing adsorbent 5 will be described. FIG. 4 is a diagram qualitatively showing the relationship between the nitrogen adsorption amount of zeolite and pressure, and FIG. 5 is a diagram qualitatively showing the relationship between the nitrogen adsorption amount of zeolite and pressure and temperature.

As shown in FIG. 4, zeolite has the property that the amount of nitrogen adsorption increases as the pressure increases. When air is brought into contact with zeolite in an atmosphere of pressure P ₁ , the zeolite becomes nitrogen until the amount of adsorption reaches the C ₁ value. To adsorb. As a result, nitrogen in the air is reduced, and oxygen enrichment is performed corresponding to the amount of reduced nitrogen. On the other hand, at the pressure P ₂ (however, P ₂ <P ₁ ), the nitrogen adsorption amount of the zeolite decreases to the C ₂ value, so that the zeolite adsorbed to the C ₁ value is adsorbed when it comes into contact with the air at the pressure P _2. The released nitrogen is released, and the amount of zeolite adsorbed decreases from the C ₁ value to the C ₂ value. The nitrogen content of the air from which the nitrogen has been released increases and nitrogen enrichment takes place.

  In other words, by contacting the air with different pressures to the zeolite, oxygen enrichment of air having a relatively high pressure is performed according to the difference in the amount of nitrogen adsorption determined by the pressure difference, while the pressure is relatively low. Nitrogen enrichment of air is performed. By alternately contacting air with different pressures to the zeolite, the zeolite repeatedly adsorbs and releases nitrogen, and even if the amount of nitrogen adsorption once reaches saturation, it does not remain saturated and is semi-permanent. Oxygen enrichment is performed.

Further, as shown in FIG. 5, the amount of nitrogen adsorbed by zeolite varies depending on the temperature, and even if the pressure is constant, the amount of nitrogen adsorbed increases as the temperature decreases. That is, when the pressure is set to a constant value of P ₃ and air having a temperature T ₁ lower than the temperature T ₂ is brought into contact with the zeolite, the zeolite absorbs nitrogen until the adsorption amount reaches the C ₃ value. As a result, nitrogen in the air is reduced, and oxygen enrichment is performed corresponding to the amount of reduced nitrogen. Meanwhile, since the nitrogen adsorption amount of the temperature T ₂ zeolite is reduced to C ₄ value, zeolite releases nitrogen adsorbed Touching the temperature T ₂ air, the amount of adsorption of zeolite C from C ₃ value Decreases to ₄ values. The nitrogen content of the air from which the nitrogen has been released increases and nitrogen enrichment takes place.

  In other words, by contacting the air with different temperatures to the zeolite, oxygen enrichment of air having a relatively low temperature is performed according to the difference in the amount of nitrogen adsorption determined by the temperature difference, while the temperature is relatively high. Nitrogen enrichment of air is performed. By alternately contacting air at different temperatures with the zeolite, the zeolite repeatedly adsorbs and releases nitrogen, and even if the nitrogen adsorption amount once reaches saturation, it does not remain saturated and is semi-permanent. Oxygen enrichment is performed.

  In this case, by increasing the pressure of the air on the oxygen-enriched side and lowering the temperature, as can be seen from FIG. 5, the difference in the amount of nitrogen adsorbed by the zeolite becomes larger, and the oxygen enrichment is efficiently performed. Can be done.

  Next, a method for producing oxygen-enriched air from air using the oxygen-enriched air production apparatus 1 using such nitrogen adsorption ability of zeolite will be described.

  In FIG. 1, the first air supply is performed while continuously or intermittently rotating the first cylindrical container 2, the second cylindrical container 3, and the third cylindrical container 4 about the axis 2a. The pressure of the air supplied from the flow path 9 is made higher than the pressure of the air supplied from the second air supply flow path 10, or the temperature of the air supplied from the first air supply flow path 9 is changed to the first The temperature of the air supplied from the second air supply flow path 10 is lower than the temperature of the air supplied from the second air supply flow path 10 or the air supplied from the first air supply flow path 9 is compared with the air supplied from the second air supply flow path 10. Air is supplied from the first air supply channel 9 and the second air supply channel 10 by increasing the pressure and decreasing the temperature. The pressure of the supplied air is adjusted by, for example, adjusting the discharge pressure of a blower for blowing air, and the temperature of the supplied air is adjusted by heat that is supplied to the supply pipe by exhaust heat from a heater or a heating furnace. This can be done by installing an exchange or the like.

  The air supplied from the first air supply flow path 9 comes into contact with the moisture absorbing adsorbent 6 filled in the second cylindrical container 3 to remove moisture (referred to as “dehydration treatment”), and then dehydrated. The minutely processed air comes into contact with the nitrogen absorbing adsorbent 5 filled in the first cylindrical container 2. Here, the air supplied from the first air supply channel 9 has a higher pressure or a lower temperature than the air supplied from the second air supply channel 10, or a higher pressure and a higher temperature. Therefore, nitrogen is adsorbed by the nitrogen absorbing adsorbent 5 made of zeolite or the like, nitrogen is reduced, and oxygen enrichment is performed (referred to as “denitrification treatment”). The denitrification treatment is also referred to as “oxygen enrichment treatment”.

  On the other hand, the air supplied from the second air supply channel 10 is contacted with the moisture absorbing adsorbent 7 filled in the third cylindrical container 4 to be subjected to the dehydration treatment and the dehydration treatment. The air flows into the first cylindrical container 2 and comes into contact with the nitrogen absorbing adsorbent 5 filled in the first cylindrical container 2. The air supplied from the second air supply channel 10 has a lower pressure or higher temperature than the air supplied from the first air supply channel 9, or a lower pressure and a higher temperature. The amount of nitrogen adsorbed by the nitrogen absorbing adsorbent 5 made of zeolite or the like is lowered by contact with the air, and nitrogen corresponding to the difference in the amount of nitrogen adsorbed is released to the air supplied from the second air supply channel 10. The Thereby, the nitrogen concentration of the air supplied from the second air supply channel 10 increases (referred to as “nitrogen enrichment process”). In this way, the nitrogen absorbing adsorbent 5 does not stay in a saturated nitrogen adsorption amount, and continuously performs nitrogen adsorption / release.

  Thereafter, the nitrogen-enriched air supplied from the second air supply channel 10 flows into the second cylindrical container 3 and contacts the moisture absorbing adsorbent 6. The moisture absorbing adsorbent 6 is in contact with the air supplied from the first air supply channel 9 and adsorbs moisture contained in the air, but is supplied from the second air supply channel 10. Since the air is dry air from which moisture has already been removed by the moisture absorbing adsorbent 7 filled in the third cylindrical container 4, the moisture adsorbed on the moisture absorbing adsorbent 6 It is discharged into the air supplied from the air supply flow path 10 and the moisture concentration of this air rises (referred to as “moisture enrichment process”). That is, the moisture absorbing adsorbent 6 does not stay in a saturated moisture adsorption amount, and continuously performs moisture adsorption / release.

  Similarly, the denitrogenated or oxygen-enriched air supplied from the first air supply channel 9 flows into the third cylindrical container 4 and contacts the moisture absorbing adsorbent 7. The moisture absorbing adsorbent 7 is in contact with the air supplied from the second air supply channel 10 and adsorbs moisture contained in the air, but is supplied from the first air supply channel 9. Since the air is dry air from which moisture has already been removed by the moisture-absorbing adsorbent 6 filled in the second cylindrical container 3, the moisture adsorbed on the moisture-absorbing adsorbent 7 is The air is supplied to the air supplied from the air supply flow path 9. In other words, the moisture absorbing adsorbent 7 does not stay in a saturated moisture adsorption amount, and continuously performs moisture adsorption / release.

  The rotation speeds of the first cylindrical container 2, the second cylindrical container 3, and the third cylindrical container 4 are rotated 180 degrees (half rotation) before the adsorption amount of each adsorbent reaches the saturated adsorption amount. As such, it may be set according to the adsorption capacity of each adsorbent.

  Thus, according to the oxygen-enriched air production apparatus 1 according to the present invention, the moisture absorbing adsorbent 6 and the moisture absorbing adsorbent 7 are arranged on both sides of the nitrogen absorbing adsorbent 5, and these Since air is supplied from the opposite direction to the adsorbent, the nitrogen absorbing adsorbent 5 absorbs nitrogen from the supplied air and supplies the absorbed nitrogen from the opposite side without being affected by moisture. The moisture absorbing adsorbent 6 and the moisture absorbing adsorbent 7 alternately repeat the adsorption and release of moisture, thereby the nitrogen absorbing adsorbent 5 and the moisture absorbing adsorbent. 6 and the moisture absorption adsorbent 7 do not remain saturated and oxygen-enriched air can be produced continuously over a long period of time.

  The oxygen-enriched air production apparatus 1 according to the present invention is not limited to the above description, and various modifications can be made. For example, in the above description, the nitrogen absorbing adsorbent 5, the moisture absorbing adsorbent 6 and the moisture absorbing adsorbent 7 are filled in separate cylindrical containers, but one cylindrical container is used. The moisture absorbing adsorbent 6, the nitrogen absorbing adsorbent 5, and the moisture absorbing adsorbent 7 may be arranged in this order inside the cylindrical container. Further, while the cylindrical container is disposed inside the tube body 13 and the air flow path is disposed inside the tube body 13, only the cylindrical container is disposed inside the tube body 13, and the air flow The road may be an independent pipe. Further, the tube body 13 may be omitted, and the air flow path may be directly attached to a cylindrical container in which the moisture absorbing adsorbent 6, the nitrogen absorbing adsorbent 5, and the moisture absorbing adsorbent 7 are arranged. . Furthermore, the oxygen-enriched air and the nitrogen-enriched air may be supplied to the oxygen-enriched air production apparatus 1 from the opposite direction to the above description. Furthermore, the structure of the first cylindrical container 2 and the second cylindrical container 3 is not limited to the above, and a lattice-like partition plate may be disposed.

  Next, a method of using oxygen-enriched air produced by the oxygen-enriched air production apparatus 1 according to the present invention as oxygen-enriched air blown into the blast furnace from the tuyere of the blast furnace side wall, burning in a heating furnace or a hot stove A method of using oxygen-enriched air used as a working gas and a method of using oxygen-enriched air as a raw material for producing high purity pure oxygen will be described.

  6 is a process diagram for supplying oxygen-enriched air produced according to the present invention to a blast furnace, FIG. 7 is a process diagram for supplying oxygen-enriched air produced according to the present invention to a heating furnace, and FIG. It is process drawing which supplies manufactured oxygen enriched air to a pure oxygen manufacturing apparatus. 6-8, the code | symbol 1 is an oxygen enriched air manufacturing apparatus, 15 is a fan, 16 is a fan, 17 is a blast furnace fan, 18 is a blast furnace, 19 is a fan, 20 is a heating furnace, 21 is a compressor, 22 is deep A cold separator 23 is a compressor.

  As shown in FIGS. 6, 7, and 8, in the present invention, air is supplied to the oxygen-enriched air production apparatus 1 (specifically, the first air supply channel described above) using a blower 16. Then, nitrogen in the supplied air is removed by the adsorbent for nitrogen absorption arranged in the oxygen-enriched air production apparatus 1 to produce oxygen-enriched air. Nitrogen adsorbed on the nitrogen-absorbing adsorbent of the oxygen-enriched air production apparatus 1 is converted into air supplied to the oxygen-enriched air production apparatus 1 from the direction opposite to the air supplied by the blower 16 by the blower 15. Released and nitrogen accumulation in the nitrogen absorbing adsorbent is prevented. The obtained oxygen-enriched air is supplied to the blast furnace 18, the heating furnace 20, and the cryogenic separator 22, and is used as a combustion gas in the blast furnace 18 and the heating furnace 20, and the cryogenic separator 22 produces pure oxygen. Used as raw material.

  That is, in FIG. 6, the oxygen-enriched air produced by the oxygen-enriched air production apparatus 1 and containing, for example, 30 to 50% oxygen is mixed with air (oxygen concentration 21%) and the oxygen concentration is about 24%. By making this mixed gas into oxygen-enriched air and blowing it to the blast furnace 18 using the blast furnace blower 17, with much less power consumption compared to the case of producing oxygen-enriched air from conventional pure oxygen, Blast furnace operation can be carried out. Naturally, the oxygen-enriched air produced by the oxygen-enriched air production apparatus 1 can be blown to the blast furnace 18 using the blast furnace blower 17 without being diluted.

  Similarly, in FIG. 7, oxygen-enriched air produced by the oxygen-enriched air production apparatus 1 and containing, for example, 25 to 35% oxygen is supplied to the heating furnace 20 as a combustion gas using the blower 19. The sensible heat of the combustion exhaust gas is greatly reduced, and the fuel consumption rate in the heating furnace 20 can be greatly reduced.

  Further, in FIG. 8, oxygen-enriched air produced by the oxygen-enriched air production apparatus 1 and containing, for example, 30 to 40% oxygen is processed in the order of the compressor 21, the cryogenic separator 22, and the compressor 23. By producing pure oxygen with an oxygen concentration of about 99.6%, pure oxygen can be produced with less total power consumption compared to the conventional case of producing pure oxygen using air as a raw material and using the cryogenic separator 22. It can be manufactured.

  Using the oxygen-enriched air production apparatus shown in FIG. 1, oxygen-enriched air blown from the tuyere of the blast furnace was produced. Here, oxygen-enriched air was produced by changing the pressure of the air supplied to the oxygen-enriched air production apparatus. FIG. 9 shows the flow chart. In FIG. 9, reference numeral 1 is an oxygen-enriched air production apparatus, 15 is a blower, 17 is a blast furnace blower, and 18 is a blast furnace.

  As shown in FIG. 9, the air supplied to the oxygen-enriched air production apparatus was subjected to oxygen enrichment treatment, and oxygen-enriched air having an oxygen concentration of 35% was obtained at the outlet of the oxygen-enriched air production apparatus. On the other hand, the oxygen concentration of the nitrogen-enriched air decreased to 11.3%.

The obtained oxygen-enriched air having an oxygen concentration of 35% was diluted with ordinary air to obtain oxygen-enriched air having an oxygen concentration of 23.5%, and this was blown into a blast furnace at a flow rate of 47000 Nm ³ / h. The power required in this case was about 53.0 MW.

  For comparison, an operation for producing oxygen-enriched air using a conventional cryogenic separator was also carried out. FIG. 10 shows a flow chart when oxygen-enriched air produced using a cryogenic separator is blown into the blast furnace tuyere. In FIG. 10, the code | symbol 17 is a blast furnace blower, 18 is a blast furnace, 22 is a cryogenic separation apparatus, 24 is a blower, 25 is a blower.

As shown in FIG. 10, pure oxygen having an oxygen concentration of approximately 100% is produced by a cryogenic separator, and this is diluted with normal air to obtain oxygen-enriched air having an oxygen concentration of 23.5%. The blast furnace was blown at a flow rate of 47000 Nm ³ / h. The power required in this case was about 59.5 MW.

  Thus, by applying the present invention to the production of oxygen-enriched air for a blast furnace, a power reduction effect of about 10% was confirmed.

In accordance with the process shown in FIG. 6, oxygen-enriched air produced by the oxygen-enriched air production apparatus was supplied to the blast furnace. Specifically, 5322 million Nm ³ / year of air is supplied to an oxygen-enriched air production apparatus, and oxygen-enriched air with an oxygen concentration of 30% is produced at a rate of 3371 million Nm ³ / year, the oxygen-enriched air 8426 one million Nm ³ / was diluted and mixed in the year of air, oxygen concentration was fed to the blast furnace to 23.5% of the oxygen-enriched air at a rate of 11797 one million Nm ³ / year. In addition, 5322 million Nm ³ / year of air is supplied to the oxygen-enriched air production apparatus as the denitrification air of the nitrogen absorbing adsorbent, and the nitrogen-enriched air (low oxygen concentration is 15.3%) Oxygen air) was discharged at a rate of 7273 million Nm ³ / year. In this case, the electric power consumed by the oxygen-enriched air production apparatus was 70 million kWh / year, and the electric power consumed by the blast furnace blast was 910 million kWh / year, which was 9.98 billion kWh / year. Moreover, the oxygen-enriched air production apparatus produced oxygen-enriched air continuously for one year without causing any problems.

  When oxygen-enriched air having the same composition and flow rate as above is blown into a blast furnace using a conventional cryogenic separation method, the power consumption is 180 million kWh / year for the cryogenic separator and 0 for oxygen pumping. 800 million kWh / year, blast furnace blasting: 880 million kWh / year, totaling 1.14 billion kWh / year, and by using oxygen-enriched air produced according to the present invention, 160 million kWh / Electricity consumption per year could be reduced.

Moreover, the oxygen concentration of the oxygen-enriched air produced by the oxygen-enriched air production apparatus was changed, and the power reduction amount at that time was obtained. Power reduction amount calculated on the assumption that used in geological storage CO _2, were evaluated by the CO ₂ reduction. FIG. 11 shows the relationship between the obtained CO ₂ reduction amount and the oxygen concentration of the oxygen-enriched air.

As shown in FIG. 11, the CO ₂ reduction amount increases as the oxygen concentration of the oxygen-enriched air increases. However, when the oxygen concentration of the oxygen-enriched air exceeds 35%, the CO ₂ reduction amount reaches its peak. In order to increase the oxygen concentration of oxygen-enriched air, the equipment cost increases due to the size of the oxygen-enriched air production device, and therefore the oxygen concentration of oxygen-enriched air produced by the oxygen-enriched air production device It was found that 30 to 35% is preferable.

In accordance with the process shown in FIG. 7, the oxygen-enriched air produced with an oxygen-enriched air production apparatus, with an oxygen concentration of 25%, is equipped with a hot blast furnace provided in an ironworks, a heating furnace for a hot rolling process, and continuous annealing. Supplied to a furnace. As a result, the sensible heat of the exhaust gas was greatly reduced, and it was possible to reduce the amount of fuel used in the past by a total of 624900 Nm ³ / h by about 8100 Nm ³ / h (ratio: about 1.3%).

Moreover, the amount of energy reduction at that time was obtained by changing the oxygen concentration of the oxygen-enriched air produced by the oxygen-enriched air production apparatus. The energy reduction amount obtained by converting the power reduction amount, further assuming the case of using the power reduction amount on the geological storage of CO _2, was evaluated in a CO ₂ reduction amount. FIG. 12 shows the relationship between the obtained CO ₂ reduction amount and the oxygen concentration of the oxygen-enriched air.

As shown in FIG. 12, the amount of CO ₂ reduction increases as the oxygen concentration of the oxygen-enriched air increases, but when the oxygen concentration of the oxygen-enriched air exceeds 50%, the CO ₂ reduction amount reaches its peak. In order to increase the oxygen concentration of the oxygen-enriched air, the equipment cost is increased by increasing the size of the oxygen-enriched air production apparatus. Therefore, the oxygen concentration of the oxygen-enriched air is more desirably 30 to 45%. It was found that 30 to 35% is preferable.

In accordance with the steps shown in FIG. 8, oxygen-enriched air produced by an oxygen-enriched air production apparatus is supplied to a cryogenic separation apparatus as a raw material for producing pure oxygen, with an oxygen concentration of 99.6% and a pressure of 500 kPa. Of pure oxygen was produced. At that time, the oxygen concentration of the oxygen-enriched air produced by the oxygen-enriched air production apparatus is changed to four levels of 25%, 30%, 35% and 40%, and the oxygen-enriched air production apparatus in each case. The power consumed and the power consumed by the cryogenic separator were investigated. For comparison, electric power when using conventional air as a raw material was also investigated. Table 1 shows the survey results when the production amount of pure oxygen is 2077 million Nm ³ / year. The column of CO ₂ reduction amount in Table 1 is evaluated as the CO ₂ reduction amount on the assumption that the power reduction amount is used for CO ₂ underground storage.

  As shown in Table 1, the higher the oxygen concentration of the oxygen-enriched air, the less power is consumed by the cryogenic separator, but the oxygen-enriched air production device also requires a predetermined amount of power, and as a result, the oxygen concentration However, when 25% oxygen-enriched air was used as the raw material, the electric power used was increased compared to when air was used as the raw material. However, when oxygen-enriched air having an oxygen concentration of 30% or more is used as a raw material, it has been confirmed that the total power consumption is improved as compared with the case where conventional air is used as a raw material.

1 is a schematic perspective view of an oxygen-enriched air production apparatus according to the present invention. It is a schematic perspective view of the 1st cylindrical container and the 2nd cylindrical container which comprise a part of oxygen-enriched air manufacturing apparatus which concerns on this invention. It is the schematic which shows the other example of the 1st cylindrical container of the oxygen enriched air manufacturing apparatus which concerns on this invention. It is a figure which shows qualitatively the relationship between the nitrogen adsorption amount of zeolite, and a pressure. It is a figure which shows qualitatively the relationship between the nitrogen adsorption amount of zeolite, pressure, and temperature. It is process drawing which supplies the oxygen enriched air manufactured with the oxygen enriched air manufacturing apparatus which concerns on this invention to a blast furnace. It is process drawing which supplies the oxygen enriched air manufactured with the oxygen enriched air manufacturing apparatus which concerns on this invention to a heating furnace. It is process drawing which supplies the oxygen enriched air manufactured with the oxygen enriched air manufacturing apparatus which concerns on this invention to a pure oxygen manufacturing apparatus. It is a flowchart when oxygen-enriched air manufactured using the oxygen-enriched air manufacturing apparatus of the present invention is blown from the blast furnace tuyere. It is a flow figure when blowing in oxygen-enriched air manufactured using the conventional cryogenic separator from a blast furnace tuyere. It is a diagram showing a relationship between oxygen concentration of CO ₂ reduction and oxygen-enriched air in the second embodiment. It is a diagram showing a relationship between oxygen concentration of CO ₂ reduction and oxygen-enriched air in the third embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Oxygen-enriched air production apparatus 2 1st cylindrical container 2a Axis center 3 2nd cylindrical container 4 3rd cylindrical container 5 Adsorbent for nitrogen absorption 6 Adsorbent for moisture absorption 7 Adsorbent for moisture absorption 8 Partition plate 9 First air supply flow path 10 Second air supply flow path 11 First air discharge flow path 12 Second air discharge flow path 13 Tubing body 14 Separation plate 15 Blower 16 Blower 17 Blast furnace blower 18 Blast furnace 19 Blower 20 Heating furnace 21 Compressor 22 Cryogenic separator 23 Compressor 24 Blower 25 Blower 26 Honeycomb structure

Claims (12)

  A nitrogen absorbing adsorbent whose amount of nitrogen adsorption increases as the pressure increases is sandwiched, and moisture absorbing adsorbents are arranged on both sides of the adsorbent, and these adsorbents are rotated around their axes, Air with different pressures is supplied to the adsorbent in the opposite direction, and these air are passed through the adsorbent for moisture absorption, the adsorbent for nitrogen absorption, and the adsorbent for moisture absorption in this order, and the pressure is relatively high. The air that has been increased is subjected to dehydration treatment, denitrification treatment, and water enrichment treatment in this order, and the air that has undergone relatively low pressure is subjected to dehydration treatment, nitrogen enrichment treatment, and water enrichment treatment. A method for producing oxygen-enriched air, characterized in that the treatment is sequentially performed and oxygen enrichment of air at a relatively high pressure is performed.   A nitrogen absorbent adsorbent whose nitrogen adsorption amount increases as the temperature decreases is sandwiched, and moisture absorbent adsorbents are arranged on both sides of the adsorbent, and these adsorbents are rotated around their axes. Air with different temperatures is supplied from the opposite direction to each adsorbent, and the air is passed through the adsorbent for moisture absorption, the adsorbent for nitrogen absorption, and the adsorbent for moisture absorption in this order. Air that has been lowered is subjected to dehydration treatment, denitrification treatment, and water enrichment treatment in this order, and air that has been relatively heated is subjected to dehydration treatment, nitrogen enrichment treatment, and water enrichment treatment. A method for producing oxygen-enriched air, characterized in that the treatment is sequentially performed to perform oxygen enrichment of air at a relatively low temperature.   A nitrogen absorbing adsorbent that increases in amount as the pressure increases and the temperature decreases is sandwiched, and moisture absorbing adsorbents are placed on both sides of the adsorbent, and these adsorbents rotate about their axes. In addition, air having different pressures and temperatures adjusted so that the pressure is relatively higher and the temperature is lower than the other is supplied from the direction opposite to each of these adsorbents. Moisture-absorbing adsorbent, nitrogen-absorbing adsorbent, and moisture-absorbing adsorbent are passed through in this order, and dehydration treatment, denitrification treatment, and water enrichment treatment are performed on air with relatively high pressure and low temperature. The air was treated in order, and the pressure was relatively lowered and the temperature was raised, and then the dehydration treatment, nitrogen enrichment treatment, and moisture enrichment treatment were conducted in this order to relatively increase the pressure and lower the temperature. Perform oxygen enrichment of air Wherein the method of oxygen-enriched air.   The oxygen-enriched air produced by performing the dehydration treatment, denitrogenation treatment, and water enrichment treatment in this order is oxygen-enriched air blown into the blast furnace from the tuyere of the blast furnace side wall, or a heating furnace or The method for producing oxygen-enriched air according to any one of claims 1 to 3, wherein the method is any one of oxygen-enriched air used as a combustion gas in a hot stove.   The oxygen-enriched air produced based on the method for producing oxygen-enriched air according to any one of claims 1 to 3 is diluted with air, and the diluted mixed gas is blown into the blast furnace. A method for producing oxygen-enriched air, characterized by using enriched air.   The oxygen concentration of oxygen-enriched air produced by performing the dehydration treatment, the denitrification treatment, and the water enrichment treatment in this order is 30 to 35%. A method for producing oxygen-enriched air as described in 1. above.   The oxygen-enriched air produced by performing the dehydration treatment, denitrification treatment, and moisture enrichment treatment in this order is oxygen-enriched air that is a raw material for producing high-purity pure oxygen. The method for producing oxygen-enriched air according to any one of claims 1 to 3, wherein the method is characterized in that:   The oxygen-enriched air according to claim 7, wherein the oxygen concentration of oxygen-enriched air produced by performing the dehydration treatment, the denitrification treatment, and the water enrichment treatment in this order is 30% or more. A method for producing chemical air.   A first cylindrical container that can rotate around an axis, and a shaft that is disposed relative to the axial direction of the first cylindrical container across the first cylindrical container, and that can rotate around the axis. Second and third cylindrical containers, a nitrogen absorbing adsorbent disposed in the first cylindrical container, a moisture absorbing adsorbent disposed in the second cylindrical container, and the first 1st air for supplying the adsorbent for moisture absorption arranged in 3 cylindrical containers, and the air passing through the second cylindrical container, the first cylindrical container, and the third cylindrical container in this order A supply flow path, and a second air supply flow path for supplying air that passes in the order of the third cylindrical container, the first cylindrical container, and the second cylindrical container in the opposite direction; , A first air discharge channel for receiving air supplied by the first air supply channel, and the second air supply channel Accordingly, characterized in that it comprises a second air discharge passage for receiving the supplied air, apparatus for producing oxygen-enriched air.   A cylindrical container rotatable around an axis, a nitrogen absorbing adsorbent disposed in the cylindrical container, and a pair of disposed relative to the cylindrical container with the nitrogen absorbing adsorber interposed therebetween Moisture absorbing adsorbent and air supply for supplying air passing in the order of the moisture absorbing adsorbent, the nitrogen absorbing adsorbent, and the moisture absorbing adsorbent from the opposite directions to the cylindrical container. An apparatus for producing oxygen-enriched air, comprising: a flow path; and an air discharge flow path for receiving air that is supplied by the air supply flow path and passes through the cylindrical container.   The adsorbent for nitrogen absorption is an adsorbent for nitrogen absorption in which the amount of adsorbed nitrogen increases with an increase in pressure, and is opposite to the adsorbent for nitrogen absorption via the air supply channel. 11. The apparatus for producing oxygen-enriched air according to claim 9, wherein the air supplied from the direction is different in pressure. 11.   The nitrogen-absorbing adsorbent is a nitrogen-absorbing adsorbent that increases the amount of nitrogen adsorbed as the temperature decreases, and is opposite to the nitrogen-absorbing adsorbent via the air supply channel. The apparatus for producing oxygen-enriched air according to claim 9 or 10, wherein the temperatures of the air supplied from different directions are different from each other.

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