JPH0229603B2 - SANSOFUKASOCHI - Google Patents

Description

[Detailed description of the invention]

[Technical Field] The present invention relates to an oxygen enrichment device for obtaining oxygen enrichment from the atmosphere. More specifically, the present invention relates to an oxygen enrichment device for obtaining oxygen-enriched air from the atmosphere using a large number of membrane elements each having an oxygen selectively permeable membrane capable of transmitting oxygen at a higher rate than nitrogen. [Prior Art] Most conventional oxygen enrichment devices using membranes are operated with a constant number of built-in membrane elements. Although such an enrichment device can obtain air enriched to a predetermined oxygen concentration at a temperature near room temperature, if the atmospheric temperature during use in the summer exceeds, for example, 30°C, the oxygen concentration will be much lower than the predetermined concentration. The drawback was that only enriched air could be obtained. In addition, in operating conditions at such high temperatures, the flow rate of enriched air obtained becomes excessive,
There was a waste of having to dispose of surplus enriched air other than the required amount. There is also a proposal for an oxygen enrichment device in which the number of membrane elements from which enriched air is taken out is variable, but in that case, a control valve is provided for each membrane element to change the number of membrane elements used. . Such a device has the drawback that the control valve has a complicated and expensive structure, and its operation during operation is also complicated. In particular, medical oxygen enrichers are used by patients in hospitals and homes, and require oxygen-enriched air at a predetermined concentration. Furthermore, they are simple devices, easy to operate, and stable. It was hoped that there would be. [Object of the invention] The present invention aims to eliminate the above-mentioned drawbacks and provide an enrichment device that can stably obtain enriched air with a predetermined oxygen concentration without waste even when the atmosphere is high in temperature such as during summer. The purpose is Yet another object of the present invention is to provide an oxygen enrichment device that is extremely simple and easy to operate. [Structure of the Invention] As a result of intensive research to achieve the above object, the present inventors have found that it is very possible to divide the membrane element group into 2 or 3 decimal blocks and to make the number of blocks variable. The present invention has been developed based on the discovery that this method is effective. That is, the present invention provides an oxygen enrichment apparatus having a large number of membrane element groups each equipped with a permselective membrane, and an extraction means for allowing air to permeate through the membrane and extracting oxygen-enriched air from the membrane element. An oxygen enrichment device characterized in that a membrane element group is divided into two or three blocks at different ratios and connected to the extraction means, and has means for adjusting the number of blocks from which oxygen-enriched air is extracted. It provides: The present invention will be explained in more detail below with reference to the drawings. FIG. 1 illustrates one embodiment of the invention. The membrane element 1 is equipped with a membrane that allows oxygen to permeate more selectively than nitrogen, and the membrane may have a planar shape, a cylindrical shape, a hollow fiber shape, or the like. A specific example thereof is one in which an oxygen permselective membrane is provided on both sides or one side of the support plate, and an outlet 2 is provided for taking out oxygen-enriched air through the membrane. . The oxygen enrichment device of the present invention is equipped with a large number of such membrane elements, and the membrane element group is divided into as few blocks as 2 or 3 blocks at different ratios based on the effective membrane area. The present invention is characterized in that oxygen-enriched air is taken out at once for each block, and that it has means for adjusting the number of blocks from which oxygen-enriched air is taken out. A specific example is shown in FIG. 1, in which the membrane element group is divided into a first block 3 and a second block 4, and the oxygen-enriched air from each block is taken out from each collection pipe 5, 6. It's starting to become easier. Furthermore, a valve 7 is provided as a means for adjusting the number of blocks, and is closed when the temperature of the air 8 sent to the membrane is high. Such valves may be manually operated or automatically operated by solenoid valves. If necessary, the temperature of the air directed to the outer surface of the membrane element, the pressure inside the membrane element or on the enriched air side, such as in the oxygen-enriched air extraction tube, or the oxygen concentration in the enriched air to be extracted. Detecting means may be provided and the opening and closing of the valve may be automatically adjusted according to the detected values. In some cases, it is possible not only to simply open and close a valve, but also to adjust its opening degree. In the case of two blocks, the effective membrane area of the first block is 60 to 80% of the total, preferably 65 to 75%, and
That of the block is 20-40%, preferably 25-35%
It is desirable that When divided into three blocks, the effective membrane area of the first block is 40-60%, preferably 45-55% of the whole, and that of the second block is 25-40%, preferably 30-55%. 40%, and the third block 10-25%, preferably 15-25
% is desirable. Further, as means for adjusting the number of blocks used, the second block,
It is desirable to install a valve only in the collection pipe of the oxygen-enriched air of the third block, and the way to adjust it is, for example, when the atmosphere is low, all blocks are used, and when the atmosphere becomes high, the first and second blocks are used. It is desirable to use two blocks, and if the temperature rises further, only the first block is used. In this way, the oxygen enrichment device of the present invention divides the membrane element group into a small number of blocks at different ratios within a specific range, and changes the number of blocks used according to changes in atmospheric temperature. 10℃～30
It is designed to stably obtain oxygen-enriched air in a predetermined concentration range over a wide temperature range of .degree. Dividing the membrane element group into a larger number of blocks is not preferable because it results in a complex and expensive device with poor operability. Regarding the effective membrane area ratio occupied by each block,
For example, in the case of two blocks, if the lower limit of the first block is less than 60%, it is easier to obtain oxygen-enriched air with a predetermined concentration or higher at high temperatures, but on the other hand, the flow rate of enriched air obtained is smaller than the predetermined value. This is not desirable because it can easily occur. Moreover, if the membrane area ratio of this first block exceeds 80%, it is not preferable because it becomes difficult to obtain oxygen-enriched air of a predetermined concentration or higher at high temperatures. In addition, for those divided into 3 blocks, 2
For higher temperatures than the block format, e.g. 35
This makes it possible to obtain enriched air with a predetermined concentration or higher even under conditions such as ℃. Under normal usage conditions, i.e. in the temperature range of 10 to 30℃, 3
A two-block system is particularly preferable because the structure and operation of the device are simpler than a two-block system. As shown in FIG. 1, a depressurizing means 10 such as a vacuum pump is usually used as a means for permeating the membrane to generate and extract oxygen-enriched air, but there is also a type that pressurizes the outside of the membrane element. obtain.
In normal cases, the enriched air taken out by such a pressure reducing means passes through a cooling means 12 having a water retention function section 11, and after condensed water is separated by a water separator 13, the enriched air is passed through a pressurizing orifice 14, The air is used as oxygen-enriched air after passing through a flow rate control valve 15 and a flow meter 16. Note that if the obtained enriched air is excessive, it is discharged as B. Further, the water separated by the water separator 13 passes through a water discharge pipe 17 and is discharged to the water retention function section 11. On the other hand, the atmosphere is controlled by 18 fan means.
It is taken into the apparatus through a filter, passes through the cooler 12, passes through the outer surface of the membrane element, and then passes around the pressure reducing means while being cooled, and is discharged as D. [Example] Thirty membrane elements each having a permselective membrane of poly-4-methylpentene-1 arranged on both sides of a support were divided into two and three blocks at the ratio shown in Table 1.
An oxygen enrichment device of the same type was assembled, and the amount of permeated enriched air obtained and its oxygen concentration were measured under the temperature conditions shown in Table 1. The results are shown in Table 1.

【table】

[Table] [Effects of the Invention] The oxygen enrichment device of the present invention has the advantage that enriched air within a predetermined oxygen concentration range can be stably obtained without waste even when the atmospheric temperature is high such as during summer. There is. Furthermore, the structure for adjusting the number of membrane element blocks to be used is very simple and can be assembled at low cost, and furthermore, its operation is extremely easy and stable. In particular, these features can be a great advantage when used for medical purposes in the home.

[Brief explanation of drawings]

FIG. 1 is a block diagram illustrating one embodiment of the oxygen enrichment device according to the present invention. In this figure, 1 is a membrane element, 3 is a first block, 4 is a second block, and 7 is a valve.

Claims (1)

[Scope of Claims] 1. An oxygen enrichment device comprising a large number of membrane element groups equipped with selectively permeable membranes, and a means for extracting oxygen-enriched air from the membrane elements by allowing air to permeate through the membranes. , wherein the membrane element group is divided into two or three blocks at different ratios and connected to the extraction means, and has means for adjusting the number of blocks from which oxygen-enriched air is extracted. conversion device. 2. The oxygen enrichment device according to claim 1, wherein the membrane element group is divided into two blocks, and the first block occupies 60 to 80% of the whole. 3 The membrane element group is divided into three blocks; the first block accounts for 40-60% of the total, the second block accounts for 25-40% of the total, and the third block accounts for 10% of the total.
25%. 4. The oxygen enrichment device according to claim 1, wherein the extraction means is equipped with a pressure reduction means.