System and method for concentrating gas
View Patent ↗Systems and methods for producing a product gas are provided. In one embodiment, a plurality of gas separation assemblies separate adsorbable components from a gas source using a plurality of micro-pumps to create gas flow through the gas separation assemblies. Various embodiments include implementation of various pressure swing adsorbtion (PSA), vacuum swing adsorbtion (VSA), and vacuum pressure swing adsorbtion (VPSA) systems utilizing the gas separation assemblies with micro-pumps. In other embodiments, micro-pumps and micro-pump assemblies are arranged in various configurations capable of providing a range of pressures and flow rates.
1. A gas separation assembly for separating product gas in a gas concentration system, comprising:
at least one micro-pump assembly, each micro-pump assembly comprising at least one micro-pump, wherein each micro-pump comprises:
an inlet for allowing gas flow into the micro-pump;
an outlet for allowing gas flow out of the micro-pump;
an actuating element responsive to a voltage applied directly across the actuating element to draw gas into a chamber from the pump inlet and expel gas from the chamber to the pump outlet, wherein the applied voltage causes the actuating element to deflect at a high frequency; and
pump valving to prevent gas from flowing through the pump outlet while the micro-pump is drawing gas into the gas chamber from the pump inlet and to prevent gas from flowing through the pump inlet while the micro-pump is expelling gas from the gas chamber to the pump outlet;
a separation bed to separate product gas from a source gas, comprising:
separation media to selectively adsorb at least one gas from the source gas to produce the product gas;
a separated gas port; and
a non-separated gas port;
wherein the separation bed is scaled according to the size of the micro-pump assembly;
a compact housing comprising the at least one micro-pump assembly and the separation bed; and
separation assembly valving to direct source gas to the non-separated gas port of the separation bed and to direct product gas from the separated gas port of the separation bed during a fill cycle;
wherein gas flows through the at least one micro-pump assembly and the separation bed during the fill cycle.
2. The gas separation assembly of claim 1 , further comprising:
an outside gas port for allowing gas flow with gas outside the separation assembly;
a product gas port for allowing product gas flow;
wherein the separation assembly valving comprises fill flow paths to connect the outside gas port to the non-separated gas port of the separation bed and to connect the separated gas port of the separation bed to the product gas port.
3. The gas separation assembly of claim 1 , wherein the separation assembly valving further directs gas to the separated gas port of the separation bed and from the non-separated gas port of the separation bed during a purge cycle.
4. The gas separation assembly of claim 1 , wherein the separation assembly valving comprises a purge flow path different than a fill flow path.
5. The gas separation assembly of claim 1 , wherein gas flows through the at least one micro-pump assembly and the separation bed during a purge cycle.
6. The gas separation assembly of claim 1 , wherein the separation assembly valving comprises:
a first valve to selectively direct source gas to the non-separated gas port of the separation bed during a fill cycle and to selectively direct gas from the non-separated gas port during a purge cycle; and
a second valve to selectively direct product gas from the separated gas port of the separation bed during the fill cycle and to selectively direct gas to the separated gas port of the separation bed during the purge cycle.
7. The gas separation assembly of claim 1 , wherein the at least one micro-pump assembly comprises:
a first micro-pump assembly for producing a fill cycle gas flow, wherein gas flows through the first micro-pump assembly and the separation bed during the fill cycle; and
a second micro-pump assembly for producing a purge cycle gas flow, wherein gas flows through the second micro-pump assembly and the separation bed during the purge cycle.
8. The gas separation assembly of claim 1 , wherein each of the at least one micro-pump assemblies comprise a plurality of micro-pumps.
9. The gas separation system of claim 1 ,
wherein the separation assembly valving routes gas to the pump inlet and from the pump outlet.
10. A system for producing a product gas, comprising:
at least one gas separation assembly according to claim 1 to separate adsorbable components from a gas source; and
a controller, comprising logic to:
control the separation assembly valving of each of the at least one gas separation assemblies to produce the product gas.
11. The system of claim 10 , further comprising:
a product tank to receive the product gas produced by the at least one gas separation assembly; and
wherein the at least one gas separation assembly is connected to the product tank.
12. The system of claim 10 , wherein the at least one gas separation assembly comprises a plurality of gas separation assemblies.
13. The system of claim 12 , wherein a first subset of the plurality of gas separation assemblies is controlled to produce the product gas in accordance with a first flow rate required by a user and second subset of the plurality of gas separation assemblies is controlled to produce the product gas in accordance with a second flow rate required by the user.
14. The system of claim 10 , wherein each of the at least one gas separation assemblies comprises a plurality of high frequency micro-pump assemblies.
15. The gas separation assembly of claim 1 , wherein the actuating element is a diaphragm.
16. The gas separation assembly of claim 1 , wherein the actuating element is actuated by a piezo element.
17. The gas separation assembly of claim 1 , wherein the actuating element is actuated at a frequency up to about 1 kHz.
18. The gas separation assembly of claim 1 , wherein the actuating element is actuated at a frequency from about 1 kHz to about 10 kHz.
19. The gas separation assembly of claim 1 , wherein the actuating element is actuated at a frequency greater than about 10 kHz.
20. The gas separation assembly of claim 1 , wherein a thickness of the separation bed is less than three times a thickness of the micro-pump assembly.
21. A gas separation assembly for separating product gas in a gas concentration system, comprising:
at least one means for pumping, comprising:
an actuating means responsive to a voltage applied directly across the actuating means to draw gas into a chamber and expel gas from the chamber, wherein the applied voltage causes the actuating means to deflect at a high frequency;
a means for separating product gas from a source gas, comprising:
media means to selectively adsorb at least one gas from the source gas to produce the product gas;
a first connection means; and
a second connection means;
wherein the means for separating product gas is scaled according to the size of the at least one means for pumping;
a housing means comprising the at least one means for pumping and the means for separating product gas; and
valving means to direct source gas to the second connection means of the means for separating product gas and to direct product gas from the first connection means of the means for separating product gas during a fill cycle;
wherein gas flows through the at least one means for pumping and the means for separating product gas during the fill cycle.
22. A system for producing a product gas, comprising:
at least one gas separation assembly according to claim 19 ; and
a means for controlling, comprising logic to:
control the valving means of each of the at least one gas separation assemblies.