Method of separating and distributing oxygen

1. A method of providing oxygen rich gas, the method comprising:

separating oxygen from ambient air with an oxygen separator in discrete pulses, one pulse at a time, wherein separating oxygen from ambient air comprises:

1) evacuating a separation column to a first pressure through a feed end of a column;

2) metering a flow of gas from a last in/first out (LIFO) buffer column into a product end of the separation column while continuing to evacuate the separation column to a second pressure;

3) stopping evacuation of the separation column while continuing the flow of gas from the LIFO buffer column at a second flow rate until a third pressure is reached in the separation column;

4) pressurizing the separation column with ambient air through the feed end to a pressure of about 1 atm; and

5) feeding air into the feed end of the column while drawing an oxygen rich gas from the product end of the separation column; and

6) repeating steps 1 through 5;

wherein the start of the pulse is synchronized with the beginning of an inhalation of a person; and

wherein the oxygen rich gas in each pulse is separated from the ambient air in real time during a nitrogen adsorption step concurrent with each inhalation.

2. The method of claim 1 wherein the pulses are delivered to a person through a nose cannula.

3. The method of claim 1 wherein each pulse of the discrete pulses is produced by a sequence of nitrogen adsorption and desorption steps driven by pressure variations such that each pass through the sequence of steps produces one oxygen pulse.

4. The method of claim 3 wherein an adsorbent column size of the oxygen separator is chosen to adsorb enough nitrogen during each pulse so that a desired maximum oxygen volume for each pulse is produced.

5. The method of claim 3 wherein a pressure in the nitrogen desorption steps is increased in variable amounts relative to a pressure of the nitrogen adsorption steps to reduce in variable amounts the volume of oxygen rich gas produced during the nitrogen adsorption steps.

6. The method of claim 5 wherein a higher pressure nitrogen adsorption step that separates the oxygen rich gas from the feed air is performed concurrent with the beginning of inhalation that is followed by a nitrogen desorption step with reduced pressure and repressurization steps that are performed during the remainder of the breathing cycle of the person.

7. The method of claim 6 wherein after the nitrogen desorption with reduced pressure and repressurization steps and before the beginning of the next inhalation, all separation activity by the oxygen separator is stopped.