JPH04922B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to an oxygen-enriched air supply device that supplies oxygen-enriched air using an oxygen selective permeation membrane to an oxygen-enriched air consumption device. It is.

(Prior Art) Attempts have been made to directly concentrate oxygen from air using polymer membranes. (For example, Tokukai Sho
49-10192, etc.) This method is suitable for oxygen concentrations of 23 to 30.
% of oxygen-enriched air can be easily obtained, so it can be widely used in oxygen-enriched air consumption equipment such as combustion, treatment of people with respiratory disorders, sludge aeration treatment, atmosphere adjustment, and oxidation in chemical processes. be.
Conventionally, as a device for supplying oxygen-enriched air to the oxygen-enriched air consumption device, as shown in FIGS. An apparatus is known in which the secondary side is connected to a vacuum pump 3 while being exposed to air and maintaining airtightness on the secondary side. In such a device, when the vacuum pump is operated, air is drawn into the module and enters the module, and the air that permeates through the membrane becomes oxygen-enriched air from the outlet of the vacuum pump and is supplied to the next oxygen-enriched air consumption device 4. be done. In order to match the amount of enriched air supplied to the oxygen-enriched air consuming device with the amount of enriched air consumed in the device, a control valve is installed on the suction side of the vacuum pump as shown in Figure 2. 5 to control the amount of oxygen-enriched air that passes through the membrane, or
Alternatively, as shown in Fig. 3, by keeping the amount of oxygen-enriched air permeating through the membrane constant and controlling the control valve 5 attached to the circulation pipe 6, excess oxygen-enriched air is pumped to the vacuum pump 3.
This is done by sending the water back to the suction side. However, in the device shown in FIG. 2, when the control valve 5 is controlled to reduce the amount of oxygen-enriched air that permeates through the oxygen selective permeation membrane 1, the differential pressure between the primary side and the secondary side becomes small and the air permeates through the membrane. The drawback was that the oxygen concentration of the oxygen-enriched air decreased. On the other hand, in the device shown in Figure 2, surplus oxygen-enriched air is returned to the suction side of the vacuum pump to maintain a constant amount of air passing through the oxygen selective permeation membrane, so the differential pressure between the primary and secondary sides is maintained constant. is constant, and the oxygen concentration of oxygen-enriched air can be maintained at a constant value. However, the power consumption of the vacuum pump remains unchanged despite fluctuations in the amount of oxygen-enriched air consumed, so the consumption of oxygen-enriched air decreases. The drawback was that the production cost per unit volume increased as the volume decreased.

(Object of the Invention) This invention was made to eliminate the above-mentioned drawbacks of conventional devices, and it is possible to always keep the oxygen concentration constant despite fluctuations in the amount of oxygen-enriched air.
It is an object of the present invention to provide an oxygen-enriched air supply device that can also maintain a constant manufacturing cost per unit volume.

(Structure of the Invention) In order to achieve the above object, the present invention includes a plurality of oxygen enrichment modules arranged in a module housing chamber having an open end to the outside, and an oxygen enrichment module connected to each module via a shutoff valve. a collection pipe for the oxygen-enriched air led out from the plurality of delivery pipes, a flow control valve connected to the collection pipe, a vacuum pump connected to the control valve, and the vacuum A consumption amount detection means for the oxygen-enriched air transferred by the pump, and an opening degree of the flow control valve is adjusted in accordance with the consumption amount of the oxygen-enriched air detected by the detection means. By providing a control means that selects the membrane area by opening and closing a cutoff valve, it is possible to obtain oxygen-enriched air with a constant oxygen concentration even when the consumption amount of oxygen-enriched air fluctuates. This makes it possible to keep the production cost constant.

(Example) Next, an example of the apparatus of the present invention will be described with reference to the drawings. Figure 1 is a schematic diagram of an oxygen-enriched air supply system assuming a turndown ratio (actual usage amount/rated flow rate) of 1/4. a, 8-b, 8-c, 8-
d are arranged in a module housing chamber 10 having an open end open to the outside. Each of the above modules accommodates an oxygen selective permeation membrane that is subdivided at the same ratio as the turndown ratio, which is set in consideration of fluctuations in the amount of oxygen-enriched air consumed. However, the ratio of subdivision of this oxygen selectively permeable membrane is not necessarily limited to the turndown ratio, but is determined to achieve the highest efficiency under fluctuating flow rates of the oxygen-enriched air consumption device, especially in the area of maximum use. All you have to do is select. Further, the oxygen selectively permeable membranes accommodated in each module do not have to have the same area.

When the ventilation fan 11 installed at the open end of the module storage chamber 10 is operated, the outside air passes through the filter 12 to remove dust and the module storage chamber 1
0. When the vacuum pump 3 is operated, the air in the module storage chamber is sucked through the oxygen selective permeation membrane housed inside the module, and the air is drawn out through the outlet pipes 13-a, 1 connected to the secondary side of each module.
Collection pipe 1 through 3-b, 13-c, 13-d
5 and then supplied to an oxygen-enriched air consumer 4. On the other hand, the remaining oxygen-depleted air in the module storage chamber is forcibly exhausted by the ventilation fan, so that fresh air is always supplied to the module storage chamber.
7-a, 7-b, and 7-c are cutoff valves attached to the outlet pipes. In FIG. 1, no cutoff valve is attached to the outlet pipe 13-d connected to the oxygen enrichment module 8-d. This is the module 8
This is to use −d as a base load and to reduce equipment costs. On the other hand, it is also possible to attach shutoff valves to all the lead-out pipes connected to each module and to sequentially switch and use them.

In the present invention, a vacuum pump 3 such as a single-stage turbo, a multi-stage turbo, or a wet multi-blade type is used. Further, the means for detecting the amount of oxygen-enriched air used in the oxygen-enriched air consumption device 4 is, for example, a flow meter installed in the enriched air supply piping to the enriched air consumption device. Alternatively, the combustion temperature detector in the device, which has been conventionally used to adjust the amount of combustion air and fuel supplied into the device, can be used as it is as the means for detecting the amount of enriched air consumed.

The signal detected by the detection means is input to the control means 9. The control means simultaneously transmits an opening adjustment signal for the flow rate control valve 14 so that the consumption amount of enriched air and the discharge amount of the vacuum pump 3 that supplies enriched air to the enriched air consumption device 4 are approximately the same. A signal is sent to appropriately open and close the shutoff valve connected to each outlet pipe according to a module selection program set in advance to select the optimal membrane area corresponding to the consumption amount of oxygen-enriched air.

In such a configuration, when the amount of enriched air consumed by the oxygen-enriched air consumption device 4 fluctuates, this amount of variation is detected by the enriched air detection means, and the discharge amount of the vacuum pump is adjusted according to the signal from the enriched air detection means. The opening degree of the flow rate control valve 14 is adjusted so that the consumption amount is approximately the same as the consumption amount of enriched air, and the shutoff valves connected to each outlet pipe are opened and closed to select the optimum module corresponding to the consumption amount of enriched air. be done. Therefore, the differential pressure between the primary side and the secondary side of the membrane is always kept substantially constant, and the oxygen concentration can be kept constant regardless of fluctuations in the amount of enriched air consumed. Furthermore, in order to prevent equipment damage in the event that the pressure on the downstream side of the oxygen selectively permeable membrane abnormally decreases due to abnormal operation, it is preferable to install a vacuum breaker valve on the suction side of the vacuum pump.

(Effects of the Invention) As explained above, the device of the present invention adjusts the opening degree of the flow rate control valve in accordance with the consumption amount of oxygen-enriched air, and also opens and closes the cutoff valve to set the optimal membrane area. This is an extremely practical device that can always maintain a constant oxygen concentration despite fluctuations in the amount of enriched air consumed, and can also maintain a constant manufacturing cost per unit volume.

[Brief explanation of drawings]

FIG. 1 is a system diagram of the device of the present invention, and FIGS. 2 and 3 are system diagrams of the conventional device. 3...Vacuum pump, 4...Oxygen enriched air consumption device, 7...Shutoff valve, 8...Oxygen enrichment module,
9...Control means, 10...Module storage chamber, 1
3... Outlet piping, 14... Flow control valve, 15...
Collection piping.

Claims (1)

[Claims] 1 A plurality of oxygen-enriched modules arranged in a module storage chamber having an open end to the outside, an oxygen-enriched air outlet pipe connected to each module via a shutoff valve, and an oxygen-enriched air outlet pipe connected to each module via a shutoff valve, and an oxygen-enriched air outlet pipe connected to each module via a shutoff valve. a collection pipe for the oxygen-enriched air, a flow rate control valve connected to the collection pipe, a vacuum pump connected to the control valve, and a consumption amount detection means for the oxygen-enriched air transferred by the vacuum pump. , a control means that adjusts the opening degree of the flow rate control valve in accordance with the consumption amount of oxygen-enriched air detected by the detection means, and also opens and closes a cutoff valve connected to each module to select a membrane area. An oxygen enriched air supply device comprising: