Schematics

Advantages
- Simplicity
- Needs less components
- Can be operated manually
Video of latest prototype
Parameters and performance
- 290 g of Zeolite LiX in Reverse Osmosis Membrane housing
- Feed: 4.4 bar compressed dry air
- Production: 1.5 l/min with 90% oxygen
Additional information
This is work in progress. Please contribute in the comments. All valuable inputs will help us define the best solution.
Hello thank you for sharing this project…please share a better overview of setup so it can be duplicated, could not figure out where the second 3 way valve is here?? On the BOM it mentions 2x 3 way valve the link however is to a different part… please provide exact festo part number or link… only seem to be one 3 way valve here also how to connect the first 3 way valve is confusing with all the tubing and where is exhaust line ??
Hi Tropez!
Thanks for pointing that out, we actually used only one 3-way valve, so the total cost of our setup is even lower. The Festo Part number is VUVS-L20-M32C-AZD-G18-F7-1C1 (https://www.festo.com/cat/de-ch_ch/products_VUVS?CurrentIDCode1=VUVS-L20-M32C-AZD-G18-F7-1C1&CurrentPartNo=575271). The exhaust line is not visible in the video but we had to add a tube because it was very loud. You don’t need to add the tube though, the exhaust can be at the valve itself.
Estimados amigos excelente trabajo me gustaria saber si tienen un enlace para descargar la programación que hicieron con arduino y una lista de materiales si fueran tan amables ,les estaria muy agradecido
Estimado Ricardo, gracias por tu comentario. En la secion “Tutorial” (http://oxygenator.geprojects.tech/index.php/sample-page/setup/tutorial/) puedes encontrar las instruciones y incluido el code para programar arduino. La lista de materiales se encuentra debajo de cada prototipo, por ejemplo aqui: https://docs.google.com/spreadsheets/d/1Byizl1OCql6mSCB2BEMvd_itFDEOLyREg240kfv4HWI/edit#gid=1216356856
Si no tienes acceso a arduino, es possible de utilisar un interrumptor de tiempo, es lo que utilizamos ahora para hacer lo mas barato y mas facil de construir.
Saludos cordiales también intenté replicar su proyecto pero solo género hasta 30% porfavor, en la presión de entrada tengo 4.4 bar pero no aumenta saludos si hay una línea de comunicación directa mucho mejor saludos cordiales
Querido Juan,
He respondido a su correo electrónico, estoy esperando su respuesta.
I attempted to emulate your set-up, but was only able to acheive 30% output even at a lower flowrate. The differences were in the size and set-up of my Zeolite chamber, which was inside a soda bottle with the inlet tube being fed to the bottom. I also wasn’t able to pressurize/depressurize my container at the speed you did, I assume due to my different valve types.
Regarding the valves, do you have a no-return valve between the zeolite chamber and the storage tank? It seems you have a flow rate valve there?
Many thanks, Aaron
Hi Aaron,
thanks for sharing your experience. We have made a similar setup with the coke bottle, it’s a cool idea! What is your input pressure from the compressor?
We usually have a needle valve between the zeolite column and the storage tank to allow for proper pressurizing. Using one could help you with your problem of properly pressurizing. Let us know!
Have you tried a PVSA variant on either the single or double column versions?
I understood that the lithium exchanged 13X zeolites desorb better under vacuum.
Excellent initiative here. Too bad the circumstances around COVID seemed to be a driving force
Hi Neox,
we got LiX from Zeochem (https://www.zeochem.com/)
The temperature of the zeolite column is rising . Is it normal ?
Yes, we also observe a rise in temperature of the zeolite column, nothing unusual.
Hello! Thank you for sharing your knowledge.
I was wondering, how do you manage to get the nitrogen out of the zeolite bed in this set up? Are the zeolite saturated and then cleaned at each cycle?
Hope the question is clear! Thank you
Hi Clarisse
Exactly, each production cycle contains a “purge” step, where by depressurization of the zeolite chamber, the nitrogen sitting in the zeolite cavities is desorbed and released to the environment. I hope this helps.
Yes thank you! Do you use a special device to depressurize, like a pump or something? Or the zeolite chamber depressurizes by itself by opening a valve?
Thank you
No, opening a housing with 2-3 bars inside is enough to desorb the nitrogen, no special device needed
Do you getting the results immediately after starting the process?
It takes a couple of minutes to reach steady state, depending on how your setup is. It takes some time though to identify the optimal cycling parameters to reach high O2 concentrations
Hello,
I would assume that using greater amount of Zeolith 13X can compensate (my) lack of Zeolith LiX.. Am I correct ?
Thank You,
Jesse
Hi Jesse,
For the same pump performance, using more 13X won’t improve on O2 output. However if you can get a bigger pump, you could get more oxygen flow to compensate for the zeolite performance.
Best
Julian
Ok Thank You,
Jesse
Hello,
I would know the reference of pressure regulator that u using i can
Thank You,
If you mean the flowmeter, you can use any flowmeter regulator that works in the range of pressures you are working. I would not recommend to buy our flowmeter as it is expensive and not optimal for this application. If you are talking about the needle valves, any needle valves work really, as we are not working at high pressures.
thank u
Hello,
I would know the reference of pressure regulator that u using if u can please.
Thank You,
Hello Julian,
I am the director of Social Impact For All, a non-profit organization in the US. We are designing a new project with hospitals in Cameroon and want to make oxygen generators following your guidance. Would it be possible? Also, how can I buy the zeolite column (or oxygen column) you used in the video?
Thank you so much for your help.
Best regards,
Zachery
Hi Zachery,
I got your email, thank you for your interest! At the moment we do not have a lot of manpower, this sounds like quite a large project! Our project is more focused on supply chain limitations and DIY than large scale hospital projects. The process of licensing and certifying our prototypes is long and costly, it depends on what your timeline and budget is. The zeolite LiX can be bought at Alibaba or Zeochem (should deliver in US)!
Hope that helps a little bit
Best
Julian
Hello, greetings from Peru, thank you very much for the information published, I was finally able to install the complete system and I obtained a concentration of 93% at 1 L / min, I used 450 g of 13X HP zeolite. I work in a metrology laboratory and the system will help me to obtain different oxygen concentration values by varying the pressure, flow and nitrogen purge time, with the generated values I will seek to calibrate oxygen sensors of medical equipment.
Hey Carlos,
thank you for your feedback and valuable insights. Those are good numbers considering you are using 13X zeolite!
3 way valve FESTO in the cost estimate sheet not marching on Amazon, It is “Baomain 4V210-08 Pneumatisches Magnetventil, 12 V, Einzelkopf, 2 Positionen, 5-Wege, mit Sockel” If I follow the link.
Please send the correct link for 3 way valve.
Just use the name of the valve and google it. Then you find different suppliers such as:
https://www.ebay.com/itm/Baomain-Pneumatic-Air-Control-Solenoid-Valve-4V210-08-Dc-12V-5-Way-2-Position-Pt-/183874111512
Hello,
It is an excellent idea and social cause you are doing. I wish to replicate the same.
I need your help in understanding the valve connection, pressurisation, depressurisation cycles and their timings.
if you can explain with timing diagram that would be of great help to understand. i am an electronic engineer, not having mechanical background. Now there is an urgent need for the portable machines to help people in India, who is worst hit at this time with lack of oxygen.
If you have the flowchart / program listing of arduino, i can understand in better way.
Kindly share what ever best possible to make me understand the exact cycles and timings.
I remain grateful to you.
with kind regards,
Nabhiraj, Kolkata, India
Dear Nabhiraj,
please check out our tutorial and different prototypes we have characterized. It should help you with most questions you have.
Best
Julian
Hey, this is a really elegant solution.
Is there a substitute for Zeolite LiX that can be used? How much would the concentration be with the substitute suggested?
Thank you
Rithwik
13X is easier to get and much cheeper. You loose approximately 15-25% performance compared to LiX
Hello Kochju,
Thanks for your excellent. I am based in IIT Kanpur India and we are currently facing tough times. Therefore i am trying to make this oxygen concentrator. I have understood almost all the components and parts of the project except the 3 way valve. Can you suggest me for what purpose you are using 3 way valve and where are you using it? Also if you can send me a real image of the complete project in one go. It would be very helpful for me.
Thanks,
shivam
Hi Shivam,
Three way because we have
1. Input of pressurized air
2. Output to Zeolite column
3. Output to purge
We do not have pictures of the single column setups, sorry. I hope the sketch and the Youtube videos are enough.
Best wishes&Stay safe
Julian
Hello,
I would know if the chamber shape is Infecting the production let’s say if I use the same amount of sieve on long with a small Diameter chamber
Or I use a short With a large diameter chamber
Yes it depends. Usually PSA is done with an L/D ratio of 5-6.
Further asking about the 3 way valve can you tell me where are these 4 connections from the 3 way valve are going?
As per my understanding 1 is for pressurized dry air supply input other is for output to the pressure meter and what about the other two?
Can you explain the connections of 3 way valve?
Thanks,
shivam
Hi Shivam,
1. Input pressurized air
2. Output to Zeolite column
3. Output to purge
the fourth connection you see is to feed the solenoid valve with pressurized air, otherwise the valve does not work.
Best
Julian
Simply want to say your article is as astonishing.
The clearness in your post is just spectacular and i could assume you’re an expert on this subject.
Well with your permission let me to grab your feed to keep updated with forthcoming post.
Thanks a million and please carry on the gratifying work.
Hi ,
Thanks for the wonderful work.
Once again i want to ask about the 3 way valve. How are you controlling the 3 way valve?
The fourth connection seems to be coming from solenoid coil the black part , am i right?
Thanks,
shivam
Hi can i use Festo valve with part no MFH-5-1/4 Mat.-Nr: 6211 and serie J123 in place of the 3 way valve that you have used?
Thanks,
shivam