JP2007022833A - Apparatus for supplying oxygen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for supplying oxygen, in which the starting characteristic of an oxygen pump element capable of supplying oxygen is improved to supply oxygen in a shorter time. <P>SOLUTION: The apparatus for supplying oxygen is provided with: the oxygen pump element having a solid electrolyte; a voltage impressing means 30 for impressing a voltage to the oxygen pump element; a voltage control means 31 for controlling the voltage impressing means 30; a heating means 32 for heating the oxygen pump element; and a temperature control means 34 for detecting the temperature of the oxygen pump element and controlling the heating means 32. When the apparatus for supplying oxygen is started, the voltage A is impressed to the oxygen pump element by the voltage control means 31 and the oxygen pump element is heated to the predetermined temperature by using the heating means 32. When the amperage of the oxygen pump element reaches the predetermined value, the voltage to be impressed to the oxygen pump element is changed from the voltage A to the voltage B enough to keep the predetermined amperage to keep the oxygen pump element in an operating state. The ratio of the voltage A to the voltage B is 1.1-5. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an oxygen supply apparatus equipped with an oxygen pump element using an oxygen ion conductive solid electrolyte.

  Conventionally, an oxygen pump element shown in FIG. 12 has been disclosed as this type of oxygen pump element (see, for example, Patent Document 1). The oxygen pump element is configured by forming electrode films 2 and 3 on both sides of the oxygen ion conductive substrate 1. Lead members 4 and 5 are respectively taken out from specific portions from the respective electrode films and connected to a power source (not shown). The oxygen ion conductive substrate 1 is held by a support material 6.

  Moreover, as this kind of oxygen pump element device, there is one as shown in FIG. 13 (for example, see Patent Document 2). In FIG. 13, the oxygen pump element 7 includes a first electrode 9 formed on a porous substrate 8 such as alumina, a thin film 10 of oxygen ion conductor, and a second electrode 11, and the first electrode film 9 is made of platinum. These fine particles are formed on the porous substrate 8, and the second electrode 11 has a structure in which a thin film obtained by combining platinum fine particles with the thin film 10 of the oxygen ion conductor is formed. The heating unit 12 includes a heater print film 14 formed by patterning a conductive paste on an insulating substrate 13 such as an alumina substrate by screen printing. The heating unit 12 is not included in the housing 15 and is in the atmosphere. Arranged in a released state.

In this configuration, when the oxygen pump element 7 is heated to a temperature at which the oxygen pump element 7 operates as an oxygen pump by the heating means 12 and a DC voltage is applied between both electrodes using the first electrode 9 as a cathode and the second electrode 11 as an anode, As shown in FIG. 5, oxygen in the air dissociated and adsorbed by the first electrode 9 moves as oxygen ions in the thin film 10 of the oxygen ion conductor and is carried to the second electrode 11 to be released into the atmosphere as oxygen molecules. The Thereby, the oxygen concentration in the container attached to the housing 15 can be reduced.
JP 2000-86204 A JP 11-23525 A

  However, in the oxygen pump element of Patent Document 1, the amount of heat during operation of the oxygen pump element concentrates on the lead members 4 and 5 and local temperature spots are generated on the oxygen ion conductive substrate 2. There was a problem that cracking occurred. For this reason, there has been a problem of how to disperse the large heat generated during the operation of the oxygen pump element without any unevenness and to provide a long-term guarantee for that portion. The timing of the voltage applied to the element is not specifically described, but it is generally considered that the voltage is applied after the oxygen pump element is heated to a predetermined temperature. There is no description about intentional fluctuation of the applied voltage.

Further, in the configuration of the oxygen pump device of Patent Document 2, since the oxygen pump element 7 and the heating means 12 are released to the atmosphere, the thermal energy from the heating means 12 is not only in the oxygen pump element 7 but also in the atmosphere. It is also used for air heating. As a result, the thermal efficiency is deteriorated, the power consumption of the heating means 12 necessary for raising the temperature to the temperature at which the oxygen pump element 7 is operated increases, and the oxygen ions of the oxygen pump element are increased. It had the problem of poor transport efficiency. Further, in the embodiment, since the heating means 12 is disposed on the upper part of the oxygen pump element 7, the oxygen pump element 7 has a drawback that most of the radiant heat is used and the convection heat of the heated air cannot be used. . In this case as well, the timing of the voltage applied to the element is not described in detail, but it is generally considered that the voltage is applied after the oxygen pump element is heated to a predetermined temperature. There is no description about intentional fluctuation of the applied voltage.

  The present invention solves the above-described conventional problems, and by intentionally changing the voltage applied to the solid electrolyte, the time during which oxygen can be supplied, that is, the start-up property as an oxygen pump element is improved. An object is to provide an oxygen supply device capable of supplying oxygen in a short time.

  In order to solve the above-mentioned conventional problems, the present invention comprises an oxygen pump element comprising a solid electrolyte, a voltage application means for applying a voltage to the oxygen pump element, a voltage control means for controlling the voltage application means, A heating means for heating the oxygen pump element; and a temperature control means for controlling the heating means by detecting the temperature of the oxygen pump element, and a voltage A is applied to the oxygen pump element by the voltage control means at startup. In addition, while heating the oxygen pump element to a predetermined temperature using the heating means, when the oxygen pump element reaches a predetermined current value, the voltage is reduced to a voltage B that maintains the predetermined current value. The operating state is set such that voltage A / voltage B = 1.1-5.

  As a result, the voltage applied to the oxygen pump element at start-up is set to voltage A, so that the time to reach a predetermined current value can be greatly shortened, and after reaching the predetermined current value, the voltage is reduced to voltage B. The relationship between the temperature of the pump element and the current value can be stabilized.

  The oxygen supply apparatus of the present invention can further shorten the rise time during which oxygen can be supplied.

  According to a first aspect of the present invention, there is provided an oxygen pump element comprising a solid electrolyte, voltage application means for applying a voltage to the oxygen pump element, voltage control means for controlling the voltage application means, and heating for heating the oxygen pump element. And a temperature control means for controlling the heating means by detecting the temperature of the oxygen pump element, and applying the voltage A to the oxygen pump element by the voltage control means at the time of startup and using the heating means. While the oxygen pump element is heated to a predetermined temperature, when the oxygen pump element reaches a predetermined current value, the oxygen pump element is reduced to a voltage B that maintains the predetermined current value, and an operating state is set. And voltage B are configured such that voltage A / voltage B = 1.1-5. As a result, the voltage applied to the oxygen pumping element at the time of start-up can be reduced to the voltage A, so that the time for reaching the predetermined current value can be greatly shortened. The balance relationship between the temperature of the pump element and the current value can be stabilized.

According to a second aspect of the present invention, there is provided an oxygen pump element comprising a solid electrolyte, voltage application means for applying a voltage to the oxygen pump element, voltage control means for controlling the voltage application means, and heating for heating the oxygen pump element. And a temperature control means for controlling the heating means by detecting the temperature of the oxygen pump element, and heating the oxygen pump element to a predetermined temperature using the heating means at the start-up Then, when the voltage control means once applies a voltage A to the oxygen pump element and reaches a predetermined current value, the oxygen pump element operates to reduce to a voltage B that maintains the predetermined current value. At this time, the relationship between voltage A and voltage B is such that voltage A / voltage B = 1.1 to 5. Thus, the voltage applied to the oxygen pump element is set to the voltage A while avoiding the risk that the solid electrolyte may be cracked at the time of startup, so that the time to reach a predetermined current value can be greatly shortened. After reaching the current value, the balance between the temperature of the oxygen pump element and the current value can be stabilized by reducing the voltage to B.

  In the third aspect of the invention, in particular, in the oxygen supply device of the first or second aspect of the invention, after the voltage to the oxygen pump element is set to the voltage B, the voltage applied to the heating unit is reduced by the temperature control unit, and The voltage applied to the oxygen pump element is further increased from the voltage B by the voltage control means, and the operating state at a predetermined current value is maintained to be in a steady state, whereby a voltage is applied to the solid electrolyte serving as the oxygen pump element. Provided is an oxygen supply device in which the power consumption required for supplying oxygen is reduced by efficiently maintaining the temperature of the solid electrolyte itself by the amount of heat generated when applying.

  According to a fourth aspect of the present invention, in particular, when the oxygen supply device according to the first or second aspect of the present invention maintains the voltage to the oxygen pump element at the voltage A and the current of the oxygen pump element reaches a predetermined value, the heating means By reducing the applied voltage to the temperature control means while maintaining the predetermined current value so as to be in the steady state, the transition time to the steady state can be made as short as possible. In addition, an oxygen supply device that suppresses the power consumption required for supplying oxygen by efficiently maintaining the temperature of the solid electrolyte itself by the amount of heat generated when a voltage is applied to the solid electrolyte serving as an oxygen pump element is provided. .

  In the fifth invention, in particular, the oxygen supply device according to any one of the third and fourth inventions is operated by using only the electric power applied to the oxygen pump element in a steady state after using the heating means at the start-up. In a steady state, the solid electrolyte itself is maintained in an operating state only by the amount of heat generated by oxygen ion conduction, so that the power consumption of the oxygen supply device can be minimized.

  In the sixth invention, in particular, with respect to the oxygen supply device according to any one of the first to fifth inventions, a blower circuit having a supply / exhaust mechanism having a heat exchanger is provided on the negative electrode side of the oxygen pump element. By being arranged, new air is forcibly supplied to the negative electrode side of the oxygen pump element, so even if the oxygen supply device has a large capacity, oxygen gas is supplied to the negative electrode side of the solid electrolyte, It becomes possible to demonstrate sufficient ability. In addition, since the air blower circuit is equipped with a heat exchanger, heat loss due to exhaust can be kept small.

  In the seventh invention, in particular, a plurality of openings are provided in the metal foil member with respect to the oxygen pump element in the oxygen supply device according to any one of the first to sixth inventions, and an insulating film is provided in the opening. A plurality of oxygen ion conductive solid electrolytes are arranged in a gas-sealed structure, the metal foil member serves as a space partition means, and a positive electrode film and a negative electrode film are formed on both surfaces of the solid electrolyte, Since the solid electrolyte is configured so that the positive electrode film and the negative electrode film are electrically connected in series, the voltage applied to a large number of solid electrolytes can be accumulated. It becomes possible to operate with a general-purpose power supply by reducing the current. In addition, since the solid electrolyte is disposed on a thin metal foil member, it has sufficient gas sealing properties and sufficient flexibility against thermal shock and thermal strain, and suppresses peeling even in the long term. Can do.

  In the eighth invention, in particular, with respect to the solid electrolyte in the oxygen supply device according to any one of the first to seventh inventions, a single positive electrode film and a negative electrode film are divided into a plurality of solid electrolytes. The positive electrode film and the negative electrode film are arranged in a pair structure that constitutes a capacitor, and the voltage applied to one solid electrolyte is the same as that of the positive electrode film. By dividing the negative electrode film, it is possible to stack up, and with a small number of solid electrolytes, the current value to the entire oxygen pump element can be kept low, and a high voltage, small current can be operated with a general-purpose power supply. .

In the ninth invention, in particular, a temperature at which the solid electrolyte can conduct oxygen ions, for example, 400, is used by using a ribbon heater as the heating means in the oxygen supply device of any one of the first to eighth inventions. It can be rapidly heated with a large electric power up to ˜600 ° C.

  According to a tenth aspect of the invention, in particular, the first electrode film that is directly bonded to the solid electrolyte with respect to the positive electrode film and the negative electrode film in the oxygen supply device according to any one of the seventh to ninth aspects; A second electrode film formed on the electrode film, the film mainly composed of the composite metal oxide component on the solid electrolyte as the first electrode film, and the film mainly composed of the noble metal component as the second electrode film By configuring the first electrode film on the first electrode film, the second electrode film is made of a highly conductive material, so that an equal potential can be applied to an electrode portion having a certain area. It was. Also, the first electrode film can enhance the electrode reaction for dissociating and adsorbing oxygen as an intermediate layer between the solid electrolyte and the second electrode film, so that a good catalytic action for changing from oxygen molecules to oxygen ions can be obtained. .

  In the eleventh aspect of the invention, in particular, by using lanthanum gallate as the solid electrolyte in the oxygen supply apparatus according to any one of the first to tenth aspects of the invention, the lanthanum gallate is a perovskite type composite metal oxide mainly composed of lanthanum and gallium. And has oxygen ion conductivity at 400 ° C. or higher. Therefore, since sufficient capability can be obtained by maintaining the operating temperature of the oxygen pump element at a relatively low temperature of about 600 ° C., deterioration of the oxygen pump element can be suppressed even in the long term.

  The twelfth aspect of the invention is particularly excellent in high-temperature oxidation by using ferritic stainless steel containing aluminum as the metal foil member in the oxygen supply device of any one of the seventh to eleventh aspects of the invention. Even if it is used for a long time at around 800 ° C., stable characteristics can be maintained.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 shows a cross-sectional configuration diagram of a solid electrolyte serving as an oxygen pump element according to the first embodiment of the present invention.

In FIG. 1, a solid electrolyte 16 is formed by molding a sintered body of substitutional type lanthanum gallate (La _0.8 Sr _0.2 Ga _0.8 Mg _0.2 O ₃ ) into a flat plate having an arbitrary thickness. On the surface, as the first electrode film, a positive electrode film 17 and a negative electrode film 18 are formed so as to exhibit oxygen ion conductivity. Here, description will be made assuming that the solid electrolyte has a size of 16 × 16 mm and a thickness of 100 μm.

For the positive electrode film 17 and the negative electrode film 18, a perovskite complex oxide having conductivity was used. Specifically, a paste obtained by mixing Sm _0.5 Sr _0.5 CoO ₃ with a cellulosic vehicle, which is an organic solvent, forms a printed film by screen printing, and after drying, is fired at 1100 ° C. An electrode film having a porosity of about 15 μm was formed.

  Further, an Au porous positive second electrode film 19 and a negative second electrode film 20 were laminated as the second electrode film on the surfaces of the positive electrode film 17 and the negative electrode film 18. In this case, a printed film was formed by screen printing using Au paste, dried, and baked at 800 ° C. to form a second electrode film having a thickness of about 3 μm. The positive second electrode film 19 and the negative second electrode film 20 can improve surface distribution unevenness on the solid electrolyte with respect to the potential when a voltage is applied between the positive electrode film 17 and the negative electrode film 18.

FIG. 2 is a schematic configuration diagram of the oxygen pump element. Here, an oxygen pump element using 36 solid electrolytes 16 will be described. Each solid electrolyte is connected to one metal foil member 21 on the negative electrode film 18 side. The metal foil member 21 is Fe-20Cr-5Al.
, 12 μm, and the metal foil member 21 is provided with 36 openings 211, 13 × 13 mm so that the surface of the negative second electrode film 20 of the solid electrolyte is exposed. An insulating film 22 is disposed around the opening 211 that has a bonding relationship with the solid electrolyte. Specifically, BaO-CaO-Al2O3-SiO2-based glass ceramic paste was formed into a printed film by screen printing, dried, and then fired at 880 [deg.] C. to form an insulating film 22 having a thickness of about 10 [mu] m. . The dimensions are an outer dimension of 18 × 18 mm and an inner dimension of 13 × 13 mm so that a part of the lead extraction portion can be formed.

  Further, a conductive film 23 is disposed on the insulating film 22 while maintaining an insulating relationship with the metal foil member 21. Specifically, a printed film was formed by screen printing using Au paste, dried, and baked at 800 ° C. to form a conductive film 23 having a thickness of about 3 μm.

  The solid electrolyte and the outer peripheral negative electrode side of the solid electrolyte are joined to the conductive film 23 by a conductive film 24 (not shown). Since the size of the solid electrolyte is 16 × 16 mm and the opening provided in the metal foil member 21 is 13 × 13 mm, the joint portion formed by the conductive film 24 has a width of 1.5 mm around the solid electrolyte. An Au paste was used as the conductive film 24, and screen printing was performed twice. Thereafter, 36 solid electrolytes were bonded and fixed to the metal foil member 21 by drying and firing at 780 ° C. while applying a predetermined load.

  By connecting the lead extraction portion formed by the conductive film 23 electrically connected to the adjacent negative second electrode film 20 of the solid electrolyte and the adjacent solid electrolyte positive second electrode film 19 side, the series circuit is electrically connected. It has become. The connection was made with a gold wire 25 of φ0.1 mm. In FIG. 2, the individual solid electrolytes are numbered in an order connected to a series circuit. The lead portion 26 finally connected to the positive second electrode film of the first solid electrolyte with respect to the 36 solid electrolytes, and the electrical conduction electrically connected to the negative second electrode film of the 36th solid electrolyte A voltage is applied to the entire oxygen pump element from the lead portion 27 connected to the membrane.

  FIG. 3 is a schematic cross-sectional configuration diagram of an oxygen supply apparatus using the oxygen pump element.

  Around one metal foil member 21 that serves as a space partitioning means for 36 solid electrolytes, an electric insulating gas sealant 28 is fixed to a support 29. In addition, the voltage application means 30 is connected to the lead portion 26 and the lead portion 27 via a conducting wire, and the voltage control means 31 is connected to the voltage application means 30. The heater 33 constituting the heating means 32 is disposed opposite to the surface on the negative electrode side, and a temperature control means 34 having means 341 for detecting the temperature of the solid electrolyte sends a signal to the heating means 32. Here, a ribbon heater made of Fe-20Cr-5Al was used as the heater 33.

  The means 341 for detecting the temperature of the solid electrolyte may be a temperature sensor or other methods. In the case of a sensor, the sensor may be disposed in the vicinity of the solid electrolyte or may be disposed at an arbitrary position. Depending on the temperature of the solid electrolyte detected by the temperature control means 34, the temperature control means 34 performs input control of the heater 33 constituting the heating means 32.

  The heat insulating members for suppressing the heat loss generated by the heater 33 are the heat insulating means 35 and the heat insulating means 36. Here, a heat insulating member molded into a flat plate mainly composed of silica and alumina was used. The heat insulating means 35 is provided with a vent hole 351 for supplying air. A space portion was provided in a wide area of the heat insulating member of the vent hole 351, and it was designed to be uniformly supplied to the negative electrode side of the solid electrolyte 16 by diffusion resistance caused by ventilation.

The outside air from the blower pump 37 is led to the vent hole 351 through the air supply passage 382 of the blower circuit 38 provided with the heat exchanger 381, and finally the heat supply is received by the heat insulating means 35 and the negative electrode side of the solid electrolyte 16 is received. To. Therefore, cold outside air does not come to the negative electrode side of the solid electrolyte 16. Thereafter, the gas is discharged to the outside through the exhaust passage 383. At this time, the air passing through the air supply passage 382 by the heat exchanger 381 obtains heat from the air passing through the exhaust passage 383.

  A gas mixing means 40 is connected to the positive electrode side of the container 39 in which the oxygen pump element is accommodated through a vent 391. The mixing means 40 includes a gas induction pipe 41, a mixed gas introduction pipe 42, a gas mixer 43, and a gas pump 44.

  About the oxygen supply apparatus comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  When a voltage of 28 V is first applied to the oxygen pump element and 200 W of electric power is supplied to the heater 33 by the temperature control means 34, the temperature of the solid electrolyte in the heat insulating means 35 and the heat insulating means 36 rises. When the solid electrolyte approaches a temperature at which oxygen ions can be conducted, which is about 400 ° C., oxygen ions are gradually conducted inside the solid electrolyte, and the current value increases. When the current value reaches 4.0 A, the voltage applied to the oxygen pump element is reduced to 22V. As a result, the oxygen pump element maintains a current value of 4.0 A at a voltage of 22V. FIG. 4 shows a control mode at the start-up for the oxygen pump element. In this example, it took about 80 seconds for the oxygen pump element to reach a predetermined current value of 4.0 A.

  When a voltage is applied to each solid electrolyte through the positive second electrode film and the negative second electrode film when the temperature at which the solid electrolyte can conduct ions is reached, oxygen near the surface on the negative electrode film side becomes oxygen. By the electrochemical reaction, the inside of the solid electrolyte moves from the negative electrode film to the positive electrode film as oxygen ions, and is released as oxygen molecules from the surface on the positive electrode film side. When a current of 4.0 A flows through the 36 oxygen pump elements made of solid electrolyte, oxygen gas of about 520 ml / min can be obtained from the positive electrode side of the oxygen pump element.

  At this time, the blower pump 37 is also activated, whereby a predetermined amount of outside air is guided to the vent hole 351 through the air supply passage 382 and finally supplied to the negative electrode side of the solid electrolyte 16 while receiving heat by the heat insulating means 35. I care. Here, 3200 ml / min of air was supplied. When the oxygen pump element is operating, oxygen is extracted from the negative electrode side of the solid electrolyte 16 to the positive electrode side, and the negative electrode side falls into a nitrogen-rich state. In order to suppress this, the air in the nitrogen-rich state is discharged to the outside through the exhaust passage 383, and new air is continuously supplied from the air supply passage 382. At this time, the air passing through the supply passage 382 by the heat exchanger 381 obtains heat from the air passing through the exhaust passage 383. The heat recovery rate by the heat exchanger 381 was designed to be approximately 50%. Here, copper fins were used as heat exchange members.

  At this time, the metal foil member is also exposed to a high temperature state in addition to the atmospheric temperature of 600 ° C., but excellent oxidation resistance can be obtained by using a ferritic stainless steel containing aluminum.

  The vicinity of the surface on the positive electrode film side becomes a state close to pure oxygen by the generated oxygen gas, and is separated from the surface on the positive electrode side and passes through the heat insulating means 36 having air permeability. Therefore, the metal foil member 21 and the gas sealant 28 which are means for partitioning the space effectively act as means for preventing gas leakage from the negative electrode film side. Further, the portion where the solid electrolyte and the metal foil member 21 are gas sealed also effectively acts as a means for preventing gas leakage from the negative electrode film side.

The oxygen gas released from the positive electrode side passes through the vent 391, and is mixed with the mixed gas by the gas induction pipe 41, the mixed gas introduction pipe 42, and the gas mixer 43 that constitute the gas mixing means 40. The In this embodiment, the mixed gas is the atmosphere. The generated mixed gas is an oxygen-enriched gas, and its flow rate is determined by the suction and discharge speed of the gas pump 44.

  The oxygen concentration in the mixed gas is determined by the mixed gas flow rate and the amount of oxygen ions flowing through the solid electrolyte, that is, the magnitude of the ionic current.

(Comparative Example 1)
In this comparative example 1, the oxygen pump element was started while applying a voltage of 22 V from the beginning. As a result, the predetermined current value of 4.0 A was reached after about 5 minutes. FIG. 5 shows a control mode at start-up for the oxygen pump element of Comparative Example 1.

(Embodiment 2)
Also in this embodiment, the same oxygen supply apparatus as that in Embodiment 1 was used. The starting method at that time will be described.

  When 200 W of electric power is supplied to the heater 33 by the temperature control means 34, the temperature of the solid electrolyte in the heat insulation means 35 and the heat insulation means 36 rises. A voltage of 28 V is applied to the oxygen pump element after 40 seconds when the solid electrolyte approaches a temperature at which oxygen ions can be conducted, which is approximately 400 ° C. As a result, oxygen ions are conducted inside the solid electrolyte at once, and the current value rises to 2A or more. Thereafter, the voltage continues to rise, and when the current value reaches 4.0 A, the voltage applied to the oxygen pump element is reduced to 22V. As a result, the oxygen pump element maintains a current value of 4.0 A at a voltage of 22V. FIG. 6 shows a control mode at the start-up for the oxygen pump element. Also in this example, it took about 80 seconds for the oxygen pump element to reach the predetermined current value of 4.0 A.

(Comparative Example 2)
In Comparative Example 2, the oxygen pump element was activated while applying a voltage of 22 V after 40 seconds when the solid electrolyte approached about 400 ° C., a temperature at which oxygen ions can conduct. As a result, the predetermined current value of 4.0 A was reached after about 5 minutes. FIG. 7 shows a control mode at start-up for the oxygen pump element of Comparative Example 2.

  Here, the difference between the first embodiment and the second embodiment will be described. In Embodiment 1, since the voltage is applied to the oxygen pump element from the beginning, the time required to reach the oxygen supply state can be further shortened depending on the magnitude of the applied voltage. However, there is a risk of causing the solid electrolyte to break, because the current is forced to flow from the point where the solid electrolyte does not reach the temperature at which oxygen ions can be conducted. In contrast, in Embodiment 2, since the voltage is applied to the oxygen pump element after the solid electrolyte reaches a temperature near which oxygen ions can be conducted, the load applied to the solid electrolyte is reduced.

(Embodiment 3)
Also in this embodiment, the same oxygen supply apparatus as that in Embodiment 1 was used. The starting method at that time will be described. FIG. 8 shows a control mode at the start-up for the oxygen pump element.

A voltage of 28 V is first applied to the oxygen pump element, and 200 W of power is supplied to the heater 33 by the temperature control means 34. When the solid electrolyte approaches a temperature at which oxygen ions can be conducted, which is about 400 ° C., the solid electrolyte gradually conducts oxygen ions and the current value increases. When the current value reaches 4.0 A, the voltage applied to the oxygen pump element is reduced to 22V. As a result, the oxygen pump element maintains a current value of 4.0 A at a voltage of 22V. Thereafter, the input to the heater 33 was gradually reduced, and the applied voltage was gradually increased so as to maintain the current value of 4.0 A of the oxygen pump element. Finally, the voltage applied to the oxygen pump element was 33 V, and the input to the heater 25 by the heating means A could be made zero. In other words, after about 6 minutes due to 33V, 4.0A, 132W generated by oxygen ion conduction, the heat insulation member was in thermal equilibrium including heat loss due to supply and exhaust, and the solid electrolyte could be steadily operable. .

(Embodiment 4)
Also in this embodiment, the same oxygen supply apparatus as that in Embodiment 1 was used. The starting method at that time will be described. FIG. 9 shows a control mode at the start-up for the oxygen pump element.

  A voltage of 28 V is first applied to the oxygen pump element, and 200 W of power is supplied to the heater 33 by the temperature control means 34. When the solid electrolyte approaches a temperature at which oxygen ions can be conducted, which is about 400 ° C., oxygen ions are gradually conducted inside the solid electrolyte, and the current value increases. When the current value reaches 4.0 A, the input to the heater 33 is gradually reduced, and the voltage applied to the oxygen pump element is further increased to 30V. Thereafter, the input to the heater 33 was reduced, and the voltage was increased to 33 V so that the current value of the oxygen pump element was maintained at 4.0 A. Eventually, after about 5 minutes, the input to the heater 33 by the heating means can be made zero, the inside of the heat insulating member becomes in thermal equilibrium including heat loss accompanying supply and exhaust, and the solid electrolyte can be steadily operable. I was able to.

(Embodiment 5)
FIG. 10 shows a schematic configuration diagram of the positive electrode side of the oxygen pump element according to the fifth embodiment of the present invention, and FIG. 11 shows a schematic configuration diagram of the negative electrode side of the oxygen pump element according to the fifth embodiment of the present invention. It is shown. Since the schematic configuration is the same as that of the first embodiment, different parts will be described. The configurations of the first electrode film and the second electrode film formed on the surface of the solid electrolyte are the same. The dimensions of the solid electrolyte 45 are 32 × 32 mm and the thickness is 120 μm. Here, the positive electrode film and the negative electrode film are divided into four parts on one solid electrolyte. The dimension of one positive electrode film and negative electrode film was 13 × 13 mm, and the interval between adjacent electrode films was 1 mm. The metal foil member 46 is the same as that of the first embodiment, and nine openings 461, 29 × 29 mm are provided.

  An insulating film 47 is disposed around the opening 461 that is in a bonding relationship with the solid electrolyte. This case is the same as in the first embodiment. The dimensions are an outer dimension of 33 × 35 mm and an inner dimension of 29.5 × 29.5 mm so that a part of the lead extraction portion can be formed. Further, a conductive film 48 is disposed on the insulating film 47 while maintaining an insulating relationship with the metal foil member 46.

  The positive second electrode film 49 and the negative second electrode film 50 divided into four are configured to be electrically connected in series. 10 and 11, individual solid electrolytes are numbered in a potential sequence connected to a series circuit.

  Specifically, three through holes 51 are arranged at the center line position of one solid electrolyte, and the positive second electrode film is electrically connected to the negative second electrode film located on the opposite side by using the through holes. It is connected to. The first negative second electrode film is a second positive second electrode film located next to the first negative second electrode film, and the second negative second electrode film is a third positive second electrode film using a through hole located in the center. The third negative second electrode film is connected to the adjacent fourth positive second electrode film. The fourth negative second electrode film is joined and connected to the conductive film 48 in which the solid electrolyte 45 is disposed on the metal foil member 46, and the conductive film 48 is provided with a portion protruding from the solid electrolyte. Utilized by a gold wire 52 is connected to the fifth positive second electrode film of the solid electrolyte located adjacent to the other. A voltage is applied to the lead portion 53 that is connected in sequence in the same manner and is finally connected to the lead portion 53 connected to the first positive second electrode film and the 36th negative second electrode film. Thus, the oxygen pump element is operated.

An oxygen supply device similar to that in Embodiment 1 was produced, and the oxygen pump element was operated. Here, 32 V was applied to the oxygen pump element, and 150 W was input to the heater by the temperature control means to start the oxygen pump element. As a result, a current of 4.0 A was allowed to flow in about 110 seconds, and then the voltage applied to the oxygen pump element was reduced to 25V. Thereafter, the heater input was gradually reduced and the applied voltage was increased so that the current value of the oxygen pump element was maintained at 4.0 A. The heater input could be zero at 37V.

  As a result, it is possible to obtain about 520 ml / min of oxygen gas from the positive electrode side of the oxygen pump element by oxygen ion conduction, and the inside of the heat insulating member is heated by supply and exhaust by 37V, 4.0A 148W generated by oxygen ion conduction The thermal equilibrium including the loss was achieved, and the solid electrolyte could be steadily operated. In addition, air supply of 3200 ml / min was performed on the negative electrode side of the oxygen pump element.

  Therefore, by dividing the electrode film with a single solid electrolyte to form a series circuit, the device voltage can be increased, and using nine solid electrolytes, the same current value as in the first embodiment can be obtained. I was able to get it. Since nine solid electrolytes are arranged on the metal foil member, and the gold wire and the lead part are connected to the seven, the manufacturing process is simplified as compared with the first embodiment.

(Embodiment 6)
Also in this embodiment, the same oxygen supply apparatus as that in Embodiment 5 was used. The starting method at that time will be described.

  First, a voltage of 32 V is applied to the oxygen pump element, and 150 W of power is applied to the heater by the temperature control means. As the solid electrolyte approaches a temperature at which oxygen ions can be conducted, the inside of the solid electrolyte gradually conducts oxygen ions, and the current value increases. When the current value reaches 4.0 A, the input to the heater is gradually reduced, and the voltage applied to the oxygen pump element is further increased to 34V. Thereafter, the voltage was increased to 37 V so that the input to the heater was reduced and the current value of the oxygen pump element was maintained at 4.0 A. Eventually, after about 6 minutes, the input to the heater by the heating means can be made zero, the heat insulation member becomes in thermal equilibrium including heat loss due to supply and exhaust, and the solid electrolyte can be operated constantly. did it.

  In the first embodiment, at the time of starting the oxygen pump element, the voltage 28V is first applied to the voltage 22V having a predetermined current value of 4.0A. Therefore, voltage A / voltage B = 28/22 = 1.27. In the fifth embodiment, when the oxygen pump element is started, a voltage of 32 V is first applied to a voltage of 24 V at a predetermined current value of 4.0 A. Therefore, voltage A / voltage B = 32/24 = 1.33. If the voltage A is increased, the starting time until the oxygen pump element reaches a predetermined current value is shortened. However, in the worst case, the solid electrolyte may lead to crack breakage. The maximum value of the voltage A is determined by the size and thickness of the solid electrolyte. If the dimensions are small and the thickness is small, voltage A / voltage B can be up to about 5. Further, when the oxygen pump element is started, the difference between the voltage A and the voltage B will be clarified at least when the voltage A / voltage B = 1.1 or more. Therefore, it can be said that the effectiveness of the present invention is manifested in the range of voltage A / voltage B = 1.1-5.

  In addition, when the input to the heating means is reduced with respect to the oxygen supply device, it is possible to shorten the time required to reach the steady state by operating without reducing the voltage to the oxygen pump element from the voltage A to the voltage B. It was.

In the embodiment, a method of indirectly heating the solid electrolyte with a ribbon heater is used as the heating means. In order to bring the solid electrolyte to a temperature at which oxygen ions can be conducted rapidly, it was most efficient to apply a large input to the ribbon heater.

  In the embodiment, lanthanum gallate is used as the solid electrolyte. However, the present invention is not limited to this, and yttrium-doped zirconia (YSZ), samarium-doped ceria (SDC), or the like may be used. However, at present, the lanthanum gallate material is the most preferable material in view of the durability of the material because the operating temperature is low as an oxygen ion conductor.

In the embodiment, Sm _0.5 Sr _0.5 CoO ₃ is used as the composite metal oxide of the first electrode film, but the present invention is not limited to this. However, since the composite metal oxide having a perovskite structure has high electrode reactivity with oxygen molecules and itself has conductivity, excellent oxygen ion conductivity can be realized. Particularly, among the perovskite complex oxides, those composed of at least one of lanthanum and samarium at the A site and at least one of cobalt, iron, and manganese at the B site, and a part of the A site is replaced by strontium It had excellent conductivity and high oxygen molecule electrode reactivity.

  In the embodiment, Fe-20Cr-5Al, which is a ferritic stainless steel containing aluminum, is used as the metal foil member. However, the present invention is not limited to this, and a material having durability against high-temperature oxidation is used. Other metal foil materials can be used if present. However, at present, ferritic stainless steel containing aluminum has excellent characteristics against high-temperature oxidation. Furthermore, it is possible to add a rare earth metal for the purpose of improving the high temperature oxidation resistance. Moreover, although 12 micrometers in thickness was used, it is thought that 5-20 micrometers is preferable as a metal foil member. That is, in order to prevent the heat generated in the solid electrolyte from being transferred to the outer peripheral portion, the thinner the thickness, the better. However, if the thickness is 5 μm or less, the handling at the time of manufacture becomes worse.

  Further, in the embodiment, as a configuration of the metal foil member, only the case where the solid electrolyte is used as a partitioning means for partitioning the space by being bonded to the negative electrode film side has been described. It may be used as a partitioning means for partitioning the space portion.

  In the embodiment, Au-based materials are used as the second electrode film and the conductive film. However, the present invention is not limited to this, and any other Ag-based material or AgPd-based material can be used as long as it has a low heat resistance and heat resistance. Things can be used.

  In the embodiment, the case where the second electrode film is further disposed on the positive electrode film and the negative electrode film on the surface of the solid electrolyte has been described. However, the present invention can be applied to a structure in which the second electrode film is not disposed. For example, if the size of the electrode film formed on the surface of the solid electrolyte is 5 × 5 mm, the flowing current value is about 0.5 A, and the potential unevenness generated on the electrode film is not so large, so the second electrode film is necessary. Don't be.

  As described above, the method for controlling an oxygen supply apparatus according to the present invention can be applied to an oxygen pump element using a solid electrolyte, and can be applied to a wide range of devices such as an air purifier, an air conditioner, a health promotion device, and a health promotion device using oxygen supply. Can be used for various purposes.

Sectional block diagram of the oxygen pump element according to the first embodiment of the present invention 1 is a schematic configuration diagram of an oxygen pump element according to a first embodiment of the present invention. 1 is a schematic cross-sectional configuration diagram of an oxygen supply device according to a first embodiment of the present invention. The figure which shows the control mode at the time of starting of the oxygen pump element in the 1st Embodiment of this invention The figure which shows the control mode at the time of starting of the oxygen pump element of the comparative example 1 The figure which shows the control mode at the time of starting of the oxygen pump element in the 2nd Embodiment of this invention The figure which shows the control mode at the time of starting of the oxygen pump element of the comparative example 2 The figure which shows the control mode at the time of starting of the oxygen pump element in the 3rd Embodiment of this invention The figure which shows the control mode at the time of starting of the oxygen pump element in the 4th Embodiment of this invention Schematic block diagram of the positive electrode side of the oxygen pump element in the fifth embodiment of the present invention Schematic block diagram of the negative electrode side of the oxygen pump element in the fifth embodiment of the present invention The figure which shows the oxygen pump element apparatus in the conventional patent document 1 reference The figure which shows the oxygen pump element apparatus in the conventional patent document 2 reference

Explanation of symbols

16, 45 Solid electrolyte 17 Positive electrode film (first electrode film)
18 Negative electrode film (first electrode film)
19, 49 Positive second electrode film 20, 50 Negative second electrode film 21, 46 Metal foil member 22, 47 Insulating film 23, 48 Conductive film 25, 52 Gold wire 26, 27, 53, 54 Lead part 30 Voltage application means 31 Voltage control means 32 Heating means 34 Temperature control means 35, 36 Heat insulation means 37 Blower pump 38 Blower circuit 381 Heat exchanger 382 Supply passage 383 Exhaust passage 40 Mixing means

Claims (12)

An oxygen pump element comprising a solid electrolyte, a voltage applying means for applying a voltage to the oxygen pump element, a voltage control means for controlling the voltage applying means, a heating means for heating the oxygen pump element, and the oxygen pump Temperature control means for controlling the heating means by detecting the temperature of the element, and applying the voltage A to the oxygen pump element by the voltage control means at the start-up and using the heating means to control the oxygen pump element When the oxygen pump element reaches a predetermined current value while being heated to a predetermined temperature, the voltage is reduced to a voltage B that maintains the predetermined current value, and the operation state is established. An oxygen supply device, wherein A / voltage B = 1.1-5. An oxygen pump element comprising a solid electrolyte, a voltage applying means for applying a voltage to the oxygen pump element, a voltage control means for controlling the voltage applying means, a heating means for heating the oxygen pump element, and the oxygen pump Temperature control means for controlling the heating means by detecting the temperature of the element, and heating the oxygen pump element to a predetermined temperature using the heating means at the time of start-up to control the voltage to the oxygen pump element. When the voltage A is once applied by the means and reaches a predetermined current value, the oxygen pump element is reduced to a voltage B at which the predetermined current value is maintained to be in an operating state, and the relationship between the voltage A and the voltage B Is a voltage A / voltage B = 1.1-5. After the voltage to the oxygen pump element is set to the voltage B, the voltage applied to the heating means is reduced by the temperature control means, and the voltage applied to the oxygen pump element is further increased from the voltage B by the voltage control means. The oxygen supply device according to claim 1, wherein the operation state at a predetermined current value is maintained to be in a steady state. While the voltage to the oxygen pump element is maintained at the voltage A, when the current of the oxygen pump element reaches a predetermined value, the voltage applied to the heating means is reduced from the temperature control means, and the predetermined current value is maintained. The oxygen supply device according to claim 1, wherein the oxygen supply device is operated in a steady state. 5. The oxygen supply device according to claim 3, wherein the operation state is maintained only by electric power applied to the oxygen pump element in a steady state after using the heating means at the start-up. The oxygen supply device according to any one of claims 1 to 5, wherein a blower circuit having a supply / exhaust mechanism including a heat exchanger is disposed on a negative electrode side of the oxygen pump element. The oxygen pump element is provided with a plurality of openings in a metal foil member, and a plurality of oxygen ion conductive solid electrolytes are gas-sealed through the insulating film in the openings, and the metal foil member is a space. A positive electrode film and a negative electrode film are formed on both surfaces of the solid electrolyte, and a plurality of solid electrolytes are configured such that the positive electrode film and the negative electrode film are electrically connected in series. The oxygen supply device according to any one of claims 1 to 6, wherein In one solid electrolyte, a positive electrode film and a negative electrode film are arranged in a pair structure in which a capacitor is formed by dividing the positive electrode film and the negative electrode film so that the positive electrode film and the negative electrode film are electrically connected in series. The oxygen supply device according to claim 1, wherein the oxygen supply device is configured as follows. The oxygen supply apparatus according to any one of claims 1 to 8, wherein the heating means is constituted by a ribbon heater. The positive electrode film and the negative electrode film are composed of a first electrode film directly bonded to a solid electrolyte and a second electrode film formed on the first electrode film, and a composite metal oxide component is formed on the solid electrolyte. The film mainly composed of the first electrode film and the film mainly composed of a noble metal component as the second electrode film are disposed on the first electrode film. The oxygen supply device according to item. The oxygen supply device according to any one of claims 1 to 10, wherein the solid electrolyte is a lanthanum gallate system. The oxygen supply device according to any one of claims 7 to 11, wherein the metal foil member is ferritic stainless steel containing aluminum.