An oxygen concentrator is a medical device that delivers supplemental oxygen to a patient whose oxygen level drops too low or has trouble breathing, via a mask or nasal cannula.
The oxygen concentrator works on the principle that the atmosphere we live in has almost 20% oxygen and 70% nitrogen. The concentrator supplies an oxygen-rich gas stream by removing 20% oxygen from nitrogen from the atmosphere, particularly ambient air.
How do Oxygen Concentrator work? It involves a five-step concentrator process:
- Takes air from the surroundings
- Compresses oxygen from the air
- Takes out nitrogen from the air
- Adjusts how oxygen needs to be delivered
- Delivers purified air to the patient
The most common technology used for separating pure oxygen from the air is known as Pressure Swing Adsorption (PSA). An oxygen concentrator comprises a compressor, oxygen tank, pressure valve, and sieve bed filter made of porous zeolite minerals.
The oxygen concentrator does not have oxygen stored in it. Instead, it produces oxygen in real-time by filtering out Nitrogen and pollutants from the ambient air so that medical grade oxygen can be supplied to the patient. The compressor of the oxygen concentrator sucks ambient air, compresses it and then moves it to the two sieve bed filters. The sieve beds are made of a crystalline zeolite material that plays a vital role in separating oxygen and nitrogen. Zeolite material of sieve beds is a six-sided microscopic cube with holes on each side that is capable of removing nitrogen from the sucked air.
As the two sieve beds are located in the concentrator, the air which is first compressed in the compressor is forced to enter the sieve beds. As the oxygen is sent to the product tank, the first sieve bed gets filled with nitrogen. The first cycle continues, and the gas flow gets switched causing the compressed air to pass to the second sieve bed. The air from the product tank returns to the first sieve bed. This causes a drop in pressure in the first sieve bed, weakening oxygen, which makes the zeolite mineral release nitrogen. The air then passes the second sieve bed after compression, where it is separated and filtered oxygen then moves to the product tank. Oxygen then passes through the nasal cannula tube or oxygen mask to be used by patients. This forms a continuous loop, hence pure oxygen continues to be transferred to the patient, while separated nitrogen is released back into the air.
While performing the entire process of filtering oxygen and releasing nitrogen, the oxygen concentrator incorporates the use of a cooling system, which prevents the device from overheating. The nasal cannula assists in delivering purified oxygen and improves oxygen absorption.
Supplemental oxygen by oxygen concentrators is medically advised for patients who have mild to moderate oxygen saturation levels between 90% to 94%. However, patients whose oxygen saturation level dips as low as 85% should only use oxygen concentrators in an emergency situation, until they are hospitalized, when they are switched to oxygen cylinders.
