초록 ▼

The present invention relates a method for concentrating a gas by applying a pressure difference to an adsorbent and an apparatus therefor, and particularly, a method for producing an enriched gas in a large amount by introducing a continuous production into every step of the process focusing on pro

The present invention relates a method for concentrating a gas by applying a pressure difference to an adsorbent and an apparatus therefor, and particularly, a method for producing an enriched gas in a large amount by introducing a continuous production into every step of the process focusing on productivity rather than concentration of the product gas and an apparatus therefor. The present invention relates to a method incorporating the vacuum swing adsorption method with the pressure swing adsorption method, particularly the rapid pressure swing adsorption method which can continuously produce a desired material in a depressurization step to improve recovery rate of the desired material and productivity and an apparatus therefor. The apparatus according to the present invention is advantageously applied in a small size machine rather than for industrial uses. Particularly, when applied in a small size oxygen concentrator, it can be used in electric home appliances, air conditioners and water purifier, as well as medical products.

대표청구항 ▼

What is claimed is: 1. A gas concentration method for separating a certain gas by applying a pressure difference to an adsorbent having an adsorption power selective for the gas, comprising: a first step of introducing a feed gas mixture through a supply port of a first adsorbent bed having a press

What is claimed is: 1. A gas concentration method for separating a certain gas by applying a pressure difference to an adsorbent having an adsorption power selective for the gas, comprising: a first step of introducing a feed gas mixture through a supply port of a first adsorbent bed having a pressure lower than the feed gas mixture, adsorbing a more adsorbable component to an adsorbent in the first adsorbent bed while desorbing the adsorbed component from a second adsorbent bed by reducing the internal pressure of the second adsorbent bed, discharging a relatively less adsorbable component through a production port of the first adsorbent bed to produce an enriched gas and supplying a part of the enriched gas to a production port of the second adsorbent bed through a microtube connecting the production ports of the adsorbent beds; a second step of reducing the internal pressure of the first adsorbent bed from the supply port to desorb the adsorbed component and increasing the pressure inside the second adsorbent bed from a supply port by supplying the feed gas mixture through the supply port of the second adsorbent bed to adsorb the more adsorbable component, in which a pressure gradient existing between the production ports and the supply ports of the first and second adsorbent beds is such that the production port of the first adsorbent bed has a pressure higher than that of the production port of the second adsorbent bed, whereby a part of the product gas is supplied from the production port of the first adsorbent bed to the production port of the second adsorbent bed, and the product gas is continuously produced during this step with a moment when the enriched gas is simultaneously produced from the production ports of the first adsorbent bed and the second adsorbent bed; a third step of reversing the pressure gradient between the production port of the first adsorbent bed and the production port of the second adsorbent bed in the second step so that the first adsorbent bed undergoes the desorption and the second adsorbent bed undergoes the adsorption, contrary to the first step, and discharging the enriched gas from the production port of the second adsorbent bed while supplying a part of the enriched gas produced from the production port of the second adsorbent bed to the production port of the first adsorbent bed; and a fourth step of supplying a part of the product gas from the production port of the second adsorbent bed to the production port of the first adsorbent bed by the pressure gradient between the adsorbent beds, contrary to the second step, increasing the pressure inside the first adsorbent bed from the supply port by supplying the feed gas mixture through the supply port to carry out the adsorption, reducing the pressure inside the second adsorbent bed from the supply port to carry out the desorption, in which the product gas is continuously produced during this step with a moment when the enriched gas is simultaneously produced from the production ports of the first adsorbent bed and the second adsorbent bed; and wherein a suction pressure by a gas discharger is always lower on at least one of the supply ports than on another supply port, whereby the gas is continuously produced. 2. The method according to claim 1, in which the gas mixture is air, the more adsorbable component is nitrogen and the less adsorbable component is oxygen. 3. The method according to claim 1 or 2, in which the adsorption pressure is atmospheric pressure and the desorption pressure is a gauge vacuum pressure measured by a vacuum pump means. 4. An apparatus for concentrating a gas comprising: a filter for filtering impurities from a feed gas mixture; at least two adsorbent beds containing an adsorbent, wherein a pressure gradient exists between a production port and a supply port of each adsorbent bed; a vacuum pump means for applying a vacuum pressure inside the adsorbent bed; a valve means for switching a path to alternately apply a vacuum pressure by the vacuum pump means and a pressure of the gas mixture; a microtube for connecting the production ports of the adsorbents; a check valve for flowing a product gas through each production port in one direction; a gas discharger for inhaling the product gas which has passed the check valve and ejecting it to a target space; and wherein a control means is provided between the check valve and the gas discharger to control the concentration and flux produced in the production port of an adsorbent bed, and wherein a suction pressure by the gas discharger is always lower on at least one of the supply ports than on another supply port, whereby a product gas is continuously produced with a moment when the enriched gas is simultaneously produced from the production ports of the at least two adsorbent beds. 5. The apparatus according to claim 4, in which a gas mixture control means is provided between the gas discharger and the filter to control the amount of the gas mixture mixed with the product gas, thereby controlling the concentration and flux of the final product gas. 6. An apparatus for concentrating a gas according to the method described in claim 1, comprising: a filter for filtering impurities from a feed gas mixture; at least two adsorbent beds containing an adsorbent; a vacuum pump means for applying a vacuum pressure inside the adsorbent bed; a valve means for switching a path to alternately apply a vacuum pressure by the vacuum pump means and a pressure of the gas mixture; a microtube for connecting the production ports of the adsorbents; a check valve for flowing a product gas through each production port in one direction; and a gas discharger for inhaling the product gas which has passed the check valve and ejecting it to a target space. 7. The apparatus according to claim 6, in which a control means is provided between the check valve and the gas discharger to control the concentration and flux produced in the production port of the adsorbent bed. 8. The apparatus according to claim 7, in which a gas mixture control means is provided between the gas discharger and the filter to control the amount of the gas mixture mixed with the product gas, thereby controlling the concentration and flux of the final product gas. 9. The apparatus according to claim 6 or 7, in which the vacuum pump means and the gas discharger can be driven by an identical motor. 10. The apparatus according to claim 6 or 7, in which the second step and the fourth step described in claim 1 are carried out by a simple path switch to between the filter and vacuum pump means by means of the valve means, with the opening and closing vacuum pressure of the check valve being low. 11. The apparatus according to claim 6 or 7, in which the check valve has an opening and closing pressure of 50 mmHg or less of a gauge vacuum pressure and the gas discharger has an adsorption pressure of 200 mmHg or less of a gauge vacuum pressure. 12. The apparatus according to claim 6 or 7, in which the valve means is a rotary valve having a rotating plate with a path driven by a motor. 13. A gas concentration method for separating a certain gas by applying a pressure difference to an adsorbent having an adsorption power selective for the gas, comprising: a first step of introducing a feed gas mixture through a supply port of a first adsorbent bed having a pressure lower than the feed gas mixture, adsorbing a more adsorbable component to an adsorbent in the first adsorbent bed while desorbing the adsorbed component from a second adsorbent bed by reducing the internal pressure of the second adsorbent bed, discharging a relatively less adsorbable component through a production port of the first adsorbent bed to produce an enriched gas and supplying a part of the enriched gas to a production port of the second adsorbent bed through a microtube connecting the production ports of the adsorbent beds; a second step of reducing the internal pressure of the first adsorbent bed from the supply port to desorb the adsorbed component and increasing the pressure inside the second adsorbent bed from a supply port by supplying the feed gas mixture through the supply port of the second adsorbent bed to adsorb the more adsorbable component, in which a pressure gradient existing between the production ports and the supply ports of the first and second adsorbent beds is such that the production port of the first adsorbent bed has a pressure higher than that of the production port of the second adsorbent bed, whereby a part of the product gas is supplied from the production port of the first adsorbent bed to the production port of the second adsorbent bed, and the product gas is continuously produced during this step with a moment when the enriched gas is simultaneously produced from the production ports of the first adsorbent bed and the second adsorbent bed; a third step of reversing the pressure gradient between the production port of the first adsorbent bed and the production port of the second adsorbent bed in the second step so that the first adsorbent bed undergoes the desorption and the second adsorbent bed undergoes the adsorption, contrary to the first step, and discharging the enriched gas from the production port of the second adsorbent bed while supplying a part of the enriched gas produced from the production port of the second adsorbent bed to the production port of the first adsorbent bed; a fourth step of supplying a part of the product gas from the production port of the second adsorbent bed to the production port of the first adsorbent bed by the pressure gradient between the adsorbent beds, contrary to the second step, increasing the pressure inside the first adsorbent bed from the supply port by supplying the feed gas mixture through the supply port to carry out the adsorption, reducing the pressure inside the second adsorbent bed from the supply port to carry out the desorption, in which the product gas is continuously produced during this step with a moment when the enriched gas is simultaneously produced from the production ports of the first adsorbent bed and the second adsorbent bed; and wherein the second step is continued after the enriched gas is simultaneously produced from the two adsorbent beds until the pressure gradient between the production ports of the adsorbent beds is reversed.