JPS6367603B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an oxygen-enriched gas supply device for combustion. In recent years, energy costs have risen significantly, and there is a strong demand for energy-saving equipment for energy-using equipment. In particular, various improvements have been made to improve the combustion efficiency of combustion equipment, internal combustion engines, external combustion engines, etc. that use energy directly as fuel. One of them is the oxygen-enriched combustion method. As is well known, chemically speaking, combustion is an oxidation reaction of fuel with oxygen, and the reaction heat generated at this time is utilized. Generally speaking, combustion has been associated with combustion in the natural atmosphere, that is, at an oxygen concentration of 21 vol%, regardless of whether it is ancient or modern.
The reaction heat generated at this time is given to the exhaust gas (for example, carbon dioxide, moisture, nitrogen gas in the air, etc.), and if it cannot be recovered, it becomes a loss of exhaust gas.
Alternatively, the combustion temperature is influenced by the exhaust gas volume. In any case, the smaller the amount of exhaust gas, the greater the available heat gain. In the exhaust gas, factors that have a major influence are the produced moisture and inert gases unrelated to combustion contained in the air, especially nitrogen. By reducing the amount of nitrogen, an increase in the combustion rate and combustion temperature can be observed, and as a result, energy savings can be achieved in large-scale combustion. Reducing the amount of nitrogen means:
The effect is to use oxygen-enriched air.
For example, as shown in FIG. 1a, a large reduction in combustion is possible even with oxygen enrichment of a few percent. In the figure, the horizontal axis shows the oxygen concentration of oxygen-enriched air, the vertical axis shows the fuel saving rate, and each combustion temperature is used as a parameter. This is an example when natural gas (13A) is used as fuel, but similar trends can be seen with other fuels. As is clear from the figure, energy saving (fuel saving effect) is better the higher the temperature is used, and is suitable for applications such as glass melting, glass processing, metal melting, ceramic firing, various forging furnaces, and general boilers. It is widely effective. Furthermore, it is understood that an increase in the oxygen enrichment rate of several to 20% will produce a significant effect, and that high concentration oxygen is not necessarily required. As a secondary effect, the use of oxygen-enriched air shortens and sharpens the flame length during combustion, for example in a pian burner, and provides an especially excellent effect for precision machining. As described above, combustion using oxygen-enriched air has many advantages, especially in its energy-saving effect, but in order to realize this, there is a strong demand for the supply of low-cost oxygen or oxygen-enriched air. It's coming. The oxygen-enriched gas currently required for combustion is
Oxygen is generally supplied by oxygen cylinders, but problems with using cylinders include the use of high-pressure gas or the need to replace the cylinders.
There is a risk of gas leakage, etc. Furthermore, liquid oxygen is also used as an alternative to cylinders, but similar problems can be seen with this as well. As mentioned above, in the current era where energy conservation is necessary, it is necessary to more efficiently extract the inexhaustible oxygen from the air. It is already known that most polymer membranes have a higher oxygen permeability coefficient than nitrogen permeability coefficient in the absence of pinholes. From this, it is obvious that polymer membranes can be used for selective separation, but when using oxygen-enriched gas obtained from equipment using polymer membranes for combustion, it is necessary to satisfy the following conditions. It is for medical use (Unexamined Japanese Patent Publication No. 1983
There is a considerable difference from the conditions required in JP-A-3291, JP-A-51-6876, etc.). This is due to the vastly different usage conditions. In general, combustion equipment uses various combustion methods, combustion temperatures,
Each device has its own shape and size, and the oxygen concentration and flow rate of the oxygen-enriched gas are determined by each device. For this reason, when oxygen-enriched gas is used in a combustion device, an oxygen-enriched gas supply device that meets these conditions is required. However, in order to satisfy the above conditions regarding the production of an oxygen-enriched gas supply device, it is not enough to simply use a device that obtains oxygen-enriched gas. In other words, it is necessary for the supply device to be able to respond to various changes in usage conditions, usage conditions, external conditions of the device, etc., and the requirements for oxygen-enriched gases used elsewhere are quite different. Specifically, the conditions necessary for the oxygen-enriched gas supply device are as follows: First, the oxygen concentration required by the combustion device can be varied. This is because when oxygen-enriched gas is mixed with gas or liquid fuel and combusted, the combustion temperature and combustion rate vary significantly depending on the oxygen concentration at that time. In other words, a mere 1% increase in oxygen concentration causes a temperature increase of about 80°C, and at the same time, a large change in combustion rate causes a large change in flame length. For this reason, as an oxygen-enriched gas supply device, it is necessary that the oxygen concentration required by the combustion device is variable. As for the second point, like the first point, it is necessary to make the flow rate of the oxygen-enriched gas variable. In other words, it is necessary to make the flow rate variable in order to achieve combustion under the conditions of the combustion device or at a value close to theoretical combustion. The third feature is that the oxygen enrichment supply device can be adapted to changes in external conditions, mainly temperature. In other words, in this device that uses a selective gas permeation membrane, the amount of gas permeation through the membrane changes due to temperature changes, and as a result, the flow rate of oxygen-enriched gas changes, so it is possible to eliminate this change. . By solving the above conditions, an oxygen-enriched gas that can be used for combustion can be obtained. The present invention solves these problems and provides an apparatus for obtaining oxygen-enriched gas that can be used for combustion.
The above-mentioned requirements will be further explained in detail below. In general, one way to obtain the optimal amount of combustion gas or the oxygen concentration and flow rate of oxygen-enriched gas for theoretical combustion appropriate to the calorie is to determine the differential pressure on both sides of the selective gas permeable membrane in the device. It is possible to change it. However, the above objective cannot be achieved simply by changing the differential pressure. The reason for this is that there is the following relationship between differential pressure and permeation flow rate. The permeation flow rate is expressed by the following equation. F(N ₂ )=K・(N ₂ )・ΔP(N ₂ ) ……(1) F(O ₂ )=K・(O ₂ )・ΔP(O ₂ ) ……(2) Here, F( N ₂ ) and F(O ₂ ) are the nitrogen and oxygen permeation amounts, K is the physical constant of the membrane, (N ₂ ) and (O ₂ ) are the nitrogen and oxygen permeability coefficients of the membrane material, respectively, and ΔP(N ₂ ), ΔP(O ₂ ) indicates the partial pressure difference between nitrogen and oxygen with respect to the film surface. In other words, as can be seen from this equation, the total flow rate (Ft) that permeates through the membrane is Ft=
F(N ₂ ) + F(O ₂ ), and by changing the differential pressure, the permeation flow rate (Ft) is controlled to the required amount, but the same is true for the oxygen concentration (F(O ₂ )/F(t)). Changes to
Figure 1b shows this based on experimental results. In this figure, air (21% oxygen) is used as the primary side. The horizontal axis in the figure shows the pressure ratio (B/A) between the pressure on the primary side of the selective gas permeable membrane (A) and the pressure on the secondary side (B) (permeated gas), and the curve P and the left vertical axis is the oxygen concentration (%) at that time, and the curve Q and the right vertical axis indicate the flow rate ratio when the permeation amount is set to 1 when B/A=0.5. As can be seen from this result, when the differential pressure is reduced, the pressure ratio (B/A) approaches 1, the permeation rate (Ft) also decreases, and the oxygen concentration (F(O ₂ )/F(t)) also decreases. It happens. The absolute value of this value changes depending on the permeation performance of the membrane and the exhaust capacity of the pump, but this tendency can be said to be the same under any conditions. In this way, obtaining the required oxygen concentration and flow rate cannot be solved simply by changing the differential pressure. Furthermore, it is necessary to take into account the following effects. In general, many polymer membranes show a tendency for the amount of permeation to increase as the temperature rises. This is shown by the following equation. =o exp−(E _p /kT) ...(3) From the above equation, the increase in permeation amount is due to the increase in (transmission coefficient) due to the rise in temperature T, and there is also a correlation with activation energy (E _p ). It is something you have. Table 1 shows an example of E _p . Figure 1c shows the temperature and oxygen permeability coefficient of polydimethylsiloxane with a small _Ep .
When the temperature increases by 10°C, the permeability coefficient increases by about 10%. In other words, this fact is largely dependent on temperature changes in the installation environment of the oxygen-enriched gas supply device, and the device needs to be adaptable to temperature changes. This is a fairly harsh environment for normally installing combustion equipment. In other words, the temperature around the device changes from around 0°C to around 40°C throughout the four seasons.
In this way, the permeation flow rate must be constantly controlled against changes of several tens of degrees. Furthermore, from Table 1, the activation energies (E _p ) of oxygen and nitrogen are not equal;
From equation (3), since the permeability coefficients depending on E _p and temperature T are different for oxygen and nitrogen, it follows that the changes in the flow rates of oxygen and nitrogen with respect to temperature changes are also not the same.

[Table] The above are the necessary conditions for an oxygen enrichment device for combustion, and the present invention aims to provide an enriched oxygen supply device for combustion that satisfies these conditions. FIG. 2 is a configuration diagram of one of the main parts of this device. This figure shows the arrangement of each part from the air inlet to the outlet and the flow of non-permeable gas. In the figure, 21 is a metal net or filter, which is provided to protect the membrane cell. Outside air is introduced through the metal net or filter 21 by a fan 22, passes through the membrane cell 1, and passes through a selective gas permeable membrane to selectively remove oxygen and water vapor. The membrane cell 1 will be described later with reference to FIG. The nitrogen-enriched gas (gas depleted in oxygen and water vapor) that does not pass through the selective gas permeation membrane then flows further to the rear by the fan 22 or is directly discharged. If the water flows to the rear, the water is evaporated and cooled in the humidity removing section 23, passes around the outer periphery of the vacuum pump 24, passes through the outer periphery of the pulsation removing section 25, and the direction is controlled by the wind direction control plate 26 that controls the direction in which the gas flows. Change and go outside. In the figure, a plurality of wind direction control plates 26 are arranged vertically, but a plurality of them may be arranged horizontally.
Further, the wind direction control plate 26 may be provided on the side or below the device. Reference numeral 27 denotes a soundproofing material, and 28 denotes an outside air introduction section provided at the rear stage of the membrane cell 1, the details of which will be described later with reference to FIG. Since the outside air introduction part 28 needs to be in contact with outside air having a constant oxygen concentration, it needs to be located away from the wind direction control plate 26 that outputs exhaust gas. Although the fan 22 is provided at the rear of the membrane cell 1 in FIG. 2, since the fan 22 is simply for flowing gas, it may be provided at the air intake or air outlet. On the other hand, FIG. 3 shows the flow of oxygen-enriched gas that has passed through the membrane. In the figure, air 30 passes through a main membrane cell 31 that is always in use and an auxiliary membrane cell 32 for controlling oxygen concentration and flow rate, and oxygen selectively permeates through the membrane. This oxygen-enriched gas advances to the vacuum pump 33, and in the middle there is an internal pressure detection section 34 for this gas and an outside air introduction section 28 for controlling oxygen concentration and flow rate. The outside air introduction section 28 introduces outside normal air (oxygen 21 vol%), dilutes the oxygen-enriched gas, and adjusts the oxygen concentration and flow rate. It is valid even if Furthermore, the enriched gas that has passed through the vacuum pump 33 passes through a dehumidification chamber 36 for removing moisture in this gas, if necessary. A part of the gas obtained here is further fed back by a feedback control 37 to control the concentration and flow rate. The remaining gas is removed as enriched combustion gas through a pulsation removal chamber 38 to remove pulsation if necessary. 35 is a temperature sensor, 90 is a flow rate sensor, 91
92 is a combustion device, and 93 is a pressure and flow rate control discharge port. The above is an overall overview of the main arrangement and flow of each part, and each will be explained in more detail. In the production of oxygen-enriched gas supply equipment for combustion,
It is possible to make a product that satisfies the required oxygen concentration and flow rate by considering the usage conditions in advance.
As mentioned above, since it is necessary to control the optimum combustion depending on the conditions of use and the environment of use, first of all, a method for making the oxygen concentration and flow rate variable will be described. In other words, it is possible to make the membrane cell part variable so that it can respond to external conditions, fluctuations, etc. FIG. 4 shows the structure of the membrane cell portion. In the figure, 1 indicates the entire membrane cell, and 45 is composed of one or more membrane cells, and under normal operating conditions.
The main membrane cell is 100% mobile. Reference numeral 46 denotes an auxiliary membrane cell, which is composed of a plurality of membrane cells and is used when operating conditions or external fluctuations occur.The proportion of the total membrane cells varies depending on various conditions, but is around 20%. In addition, in order to control this auxiliary membrane cell 46, 1
The control valve 47 has more than one control valve 47.
This configuration has one or more sets of auxiliary membrane cells 46 for each. Further, this valve 47 is a manual or electric valve with ON-OFF control. In operation, valve 47 is opened so that the oxygen-enriched gas in auxiliary membrane cell 46 passes through conduit 48 and the oxygen-enriched gas in main membrane cell 45 passes through conduit 49.
It will be merged with. By controlling the number of auxiliary membrane cells that are opened, the flow rate or oxygen concentration of the oxygen-enriched gas obtained from the membrane cell 1 can be controlled. When the auxiliary membrane cell 46 is used, the change in the oxygen-enriched gas is relatively small, the change in pressure is small, the fluctuation in oxygen concentration is small, and the flow rate can be significantly increased. Next, FIG. 5 will be explained. As shown, the flow of oxygen-enriched gas from membrane cell 1 is shown to flow through conduit 49, with pressure sensor 50 along the way.
pass through. This is to know the pressure on the permeate gas side of the membrane, and from this, the state of the permeate gas can be determined from the membrane characteristic temperature, flow rate, etc. Also, conduit 5
In order to change the state of the oxygen-enriched gas along the path through the air inlet 1, an air intake 52 corresponding to the air inlet 28 in FIGS. 2 and 3 is provided. this is,
A filter is used at the intake port 52, and the intake flow rate is adjusted by a valve 53. This valve 53 is a variable flow rate type,
It can be varied manually or by motor. The function of this device is that it can be used, for example, when the oxygen concentration is higher than the specified value and the flow rate is low.This control is a balance between the auxiliary membrane valve 47 described above and the control method described later. Needless to say. Next, the conduit 51
The gas that has passed through reaches the decompression pump 55,
A valve 57 is provided for connecting this conduit 54 and the pump discharge side conduit 56. Like the valve 53, this valve 57 is of a variable flow rate type and can be controlled manually or by a motor. Also, the role of the valve 57 is that of the conduit 4.
This is a bypass for changing the degree of pressure reduction on the 49, 51 side. By opening this, gas is circulated from the pump discharge side conduit 56 to the 49, 51 side.
The degree of pressure reduction on the 9 and 51 sides deteriorates, and the oxygen concentration and flow rate of the permeated gas are reduced to reach the specified values. It goes without saying that the control of this valve 57, like the valve 53, is correlated with various conditions, that is, whether or not the auxiliary membrane valve 47 and the air intake valve 53 are used, and factors such as temperature, pressure, and flow rate. The above is a control unit for obtaining a specified flow rate and a specified oxygen concentration necessary for the oxygen-enriched gas for combustion, and for obtaining a constant value in response to fluctuations in external conditions. It is also possible to operate all or part of the control valves manually. As already mentioned, in order to control fluctuations due to temperature, a temperature sensor 59 is attached to the membrane cell 1 part, and the temperature is constantly monitored, and when a temperature change occurs, the auxiliary membrane 46 is used and outside air is introduced in the same way as described above. , analyze whether the bypass valve 57 can be opened or closed and achieve the specified value. As mentioned above, in this device, temperature, pressure, permeation flow rate, and oxygen concentration are correlated with each other, and these can be controlled manually, but if you use the automatic centralized control method described later, you can control them in real time. Control is also possible. Since the oxygen-enriched gas obtained from the pump exhaust port 58 contains moisture, it is necessary to remove this moisture if necessary. Particularly when atmospheric humidity is high, when water vapor passes through the pump 55 from a reduced pressure state to normal pressure or higher, dew condensation occurs due to the relative temperature difference with the outside temperature. Taking advantage of this fact, water vapor is usually passed through a spiral tube and brought to room temperature to condense and extract the water vapor. However, a problem arises in that the humidity and the amount of dew condensation change depending on the outside temperature. In order to reduce the humidity in the permeated gas as much as possible with this device, we solved the problem using the following method. Ideally, humidity can be reduced by passing permeate gas through a temperature below 0°C, but using such a method increases the cost of equipment and maintenance. Inevitable.
Therefore, in this device, we solved the problem by making it as simple as possible and keeping the temperature below room temperature. In other words, a material that allows water to easily permeate and a material that has good thermal conductivity are brought into close contact with each other and connected to the permeation gas conduit. The principle behind this is that when water vapor in the permeated gas condenses in this conduit, this water is taken out to the outside by osmotic pressure or internal pressure.
When it vaporizes in the atmosphere, it further lowers the temperature due to latent heat, thereby further lowering the temperature and promoting dew condensation. FIG. 6 shows a configuration in which a dehumidifying section and a pulsating flow removing section are provided, and the same parts as in FIG. 5 are given the same reference numerals and explanations are omitted. As shown in the figure, the dehumidifying section 62 described above must be installed immediately after the pump 55. The dehumidified oxygen-enriched gas passes through the dehumidifying section 62 and further heads toward the pulsation removing section 25, and a part of it is fed back via the valve 57. If the water is fed back without passing through the dehumidifying section 62, dew condensation will occur near the valve 57, and at the same time as the flow rate changes, water vapor will further flow back. The oxygen-enriched gas dehumidified as described above may still cause pulsations in its flow. Therefore, this pulsation is prevented by the pulsation removing section 25. Further, this gas passes through a flow rate sensor section 90 and a pressure gauge 91. Also, when the conduit 92 in this part is under abnormal pressure (such as when the conduit to the combustion burner system is stopped) or the flow rate is too large, the valve 92
It is installed so that the pressure is automatically reduced or discharged. This oxygen-enriched combustion gas is sent to conduit 92 and mixed with combustion gas or liquid fuel from conduit 94. In addition, a flow rate sensor 9 is installed in the combustion part or combustion fuel part outside of this device.
5. By providing a pressure sensor 96, it is possible to obtain a higher quality oxygen-enriched gas. Figure 7 shows an embodiment in which the overall length of the device is shortened to make it more compact.The membrane cell section 1 is placed on the upper level, the other parts are placed on the lower level, and the gas flow is made into a U-shape. . Each symbol in the figure is shown in Figures 2 and 4.
Each part is the same as that shown in FIG. 5, FIG. 6, and the explanation thereof will be omitted. In this embodiment, the filter 21
Since the nitrogen-enriched gas discharge port and the nitrogen-enriched gas outlet face in the same direction, if a large amount of nitrogen-enriched gas is to be discharged from the wind direction control plate 26, the direction of the wind direction control plate 26 should be widened in the left and right direction. Chemical gas is filter 2
You have to make sure that it doesn't go around to 1. Next, a control method for stably supplying the above-mentioned specified flow rate and oxygen concentration will be described. The control parts for obtaining these are three points: opening and closing of the auxiliary membrane, operation of the atmosphere introduction valve, and the operation of the bypass valve, and any of these operations is a function of the flow rate and oxygen concentration. On the other hand, regarding these operations, the means for knowing the flow rate and oxygen concentration are several points: temperature near the membrane, pressure of permeate gas, and flow rate or pressure at the final outlet. Although these relationships appear to be complicated operations, they can be automatically controlled. That is, the membrane properties used are specific to the membrane material. Therefore, the differential pressure (ΔP) of the membrane itself, the amount of permeation (J),
This is possible by knowing the oxygen concentration (O ₂ ) and the permeability coefficient (P _T ) with respect to temperature and performing simple calculations. Specifically, we use a microcomputer to measure multiple locations on the sensor part, observe fluctuations from the specified value based on the results, and calculate and compare this with the characteristics of the membrane itself to obtain the optimal flow rate and concentration. predict and determine which of several control valves is best to change. Specifically, control is performed using the configuration shown in FIG. 111, 112,
113 is an input from each sensor. For example, line 111 is an input from pressure sensor 50 in FIG. 5, which is normalized by operational amplifier 114, passed through selector 115, and A/D converted by processing circuit 116 for calculation and other processing. A line 112 is the output of the temperature sensor 59 shown in FIG. 5, and after being corrected for the room temperature, it enters the operational amplifier 114 and is applied to the processing circuit 116 via the selector 115. Similarly, line 113 is the output of flow rate sensor 90 in FIG. 6, which is applied to processing circuit 116 via operational amplifier 114 and selector 115.
The data calculated and processed by the processing circuit 116 is compared with the film characteristics stored in the ROM 117, for example, the characteristics shown in FIG. 1b. This data is the basic data for the membrane used. On the other hand, initial values for combustion conditions can be set using the keyboard 16.
Input from step 3. 164 is a display device for the keyboard 163. The specified conditions are determined by comparing the values entered from the keyboard 163 and the film characteristics, and then the control method is determined and displayed. At the same time, an instruction is given to the valve drive motor controller 120 to drive the valve 53. Similarly, the valve 57 is a valve drive controller 121, and the valve 47
is controlled by a valve drive controller 122.
Accuracy increases by repeating this action. The data and correction data at this time are RAM118
is stored in Control is performed using the method described above. In addition, 166 in the figure shows an example of a CPU, and although it differs depending on the type of CPU, in short, various data are compared and calculated with the film characteristics to determine the optimum conditions of the control method. Furthermore, with this method, it is possible to further correct the film properties and proceed with optimization in response to complex changes in external conditions. FIG. 9 shows the above method seen from the software perspective. Next, the electric circuit and safety device circuit of this device will be explained with reference to FIG. In the figure, the solid line is the power supply circuit, and the broken line is the control circuit. First, the voltages from the vacuum pump driving three-phase power supply 131 and the single-phase 100V power supply 132 pass through power supply prevention breakers 133 and 134, respectively, and enter the opening/closing control box 135. Further, each power source is supplied through thermal overcurrent prevention breakers 136 and 137. A 100V power supply 140 is DC converted as necessary in each controller. This power supply includes a CPU 166, a fan 22, and an indicator lamp 15.
4, supplied to the alarm buzzer 150 and the control controller 144 of each valve. The power supply 145
This is a CPU backup power supply and a power supply for the alarm buzzer 146, which is used in the event of an abnormality or power outage of the 100V input power supply 132. Next, regarding the control circuit, data is input through line 147, and when an abnormal value (such as a large deviation from a specified value or an uncontrollable value) is detected, the control circuit drives the opening/closing control box 135 through line 148. It instructs to shut off the power, activate the alarm buzzer 150 via line 149, and control the controller 144 via line 151. 15
Reference numerals 2, 153, 154, and 155 are lamps or LED display devices for displaying various operating states. Since the membrane used in this device is intended for combustion, it is preferable to use a membrane material containing polydimethylsiloxane, which has good permeability, in order to obtain a flow rate of at least 20 min. Generally speaking, the oxygen concentration used for combustion is 39
% or less. The above method makes it possible to vary the oxygen concentration and flow rate, which are the main conditions required for combustion, and the specified concentration and flow rate do not fluctuate due to external conditions such as temperature, and are also stable against humidity. The oxygen-enriched gas is more stable and has no pulsation, and is sufficiently usable for combustion.

[Brief explanation of drawings]

Figure 1a is a diagram showing the relationship between oxygen concentration and fuel saving rate, Figure 1b is a diagram showing the relationship between the pressure ratio on both sides of the selective gas permeation membrane, oxygen concentration and flow rate, and Figure 1c is a diagram showing the relationship between the selective gas permeation membrane. A diagram showing the relationship between membrane temperature and permeability coefficient, FIG. 2 is a diagram showing the principle configuration of the combustion oxygen-enriched gas supply device according to the present invention, and FIG. 3 is a diagram showing the configuration of the combustion oxygen-enriched gas supply device according to the present invention. and a block diagram for explaining the operating principle, FIG. 4 is a configuration diagram of the membrane cell used in the present invention, FIG. 5 is an explanatory diagram of the oxygen enriched gas system in the device of the present invention, and FIG. 6 is a diagram of the present invention. FIG. 7 is a diagram showing the overall configuration of the device, FIG. 7 is a configuration diagram showing an embodiment of the device of the present invention, FIG. 8 is an explanatory diagram of the control system of the device of the present invention, and FIG. 9 is an illustration of the operation of the control system of the device of the present invention. The flowchart shown in FIG. 10 is an explanatory diagram of the electric circuit system in the apparatus of the present invention. 1... Selective gas permeable membrane cell, 21... Filter, 22... Fan, 23... Humidity removal section, 2
4, 33, 55...Vacuum pump, 25...Pulsation removal unit, 26...Wind direction control board, 27...Soundproofing material, 2
8... Outside air introduction part, 31, 45... Main membrane cell, 3
2, 46... Auxiliary membrane cell, 34, 50... Internal pressure detection section, 35... Temperature detection section, 36... Dehumidification chamber, 37... Feedback control, 38
...Pulsation removal chamber, 90...Flow rate detector, 91...
Pressure detector, 92... Combustion device, 93... Pressure, flow rate control discharge port.

Claims (1)

[Scope of Claims] 1. A selective gas permeable membrane cell, means for supplying air to the supply side of the selective gas permeable membrane cell, and a first piping system provided on the permeation side of the selective gas permeable membrane cell. , means located downstream of the first piping system to reduce the pressure in the first piping system to create a pressure difference between the supply side and the first piping system on the permeation side of the selective gas permeable membrane cell; a second piping system provided on the outlet side of the means for creating a pressure difference and supplying the oxygen-enriched gas that has passed through the selective gas permeable membrane cell to the combustion device; and a supply side of the selective gas permeable membrane cell. means for variably controlling the difference between the pressure of The means for variably controlling the difference connects the first piping system and the second piping system across the means for merging the gas that has passed through the auxiliary membrane cell with the gas that has passed through the main membrane cell and the means for creating a pressure difference. 1. An oxygen-enriched gas supply device for combustion, comprising at least a feedback bypass path. 2. The auxiliary membrane cell is composed of a plurality of membrane cells,
The oxygen-enriched gas supply device for combustion according to claim 1, wherein each output path is openable and closable.