Two views of the M19O2 oxygen concentrator

Design Improvements Make DIY Oxygen Concentrator Even Better

A lot of projects we feature on these pages are of the “one and done” variety — tactical builds that serve a specific purpose with little need for further development. Some projects, though, come out as rough prototypes and then go through multiple rounds of refinement, a process we really enjoy tracking down and following. And when the project is something as important as an oxygen concentrator that can be built and maintained easily, all the better.

The need for cheap oxygen concentrators stems directly from the COVID-19 pandemic, which suggested that high-flow oxygen therapy was a better choice than invasive intubations and mechanical ventilation. But medical-grade oxygen isn’t always easy to come by in all parts of the world, so easily built oxygen concentrators, which rely on the nitrogen-adsorbing properties of the mineral zeolite, are meant to fill the gaps. Early versions of the M19O2 and the related OxyKit concentrator, had a very homebrew feel to them, built on wooden frames as they were. And while the rustic nature of the early builds didn’t detract from their utility, the hackers behind them, including our own [Anool Mahidharia], have been making incremental improvements aimed at not only making the devices work better, but also making them easier to build.

The hackers at Maker’s Asylum have done a fantastic job at documenting their work, with everything posted to a GitHub repo so that anyone can undertake a build. And really, for something as important as making oxygen when it’s needed, there’s really no reason not to give this a try.

Open-Source Oxygen Hack Chat

Join us on Wednesday, May 5 at noon Pacific for the Open-Source Oxygen Hack Chat with Maher Daoudi and the OxiKit Team!

In such tumultuous times, it may be hard to remember last week, let alone last year. But if you dig back a bit, you may recall what a panic the world was in at this point in 2020 about the ventilator crisis. With COVID-19 cases on the rise and the potential for great numbers of patients needing intensive care, everyone and their brother was hacking together makeshift ventilators, in the well-intentioned belief that their inventions would help relieve the coming shortage of these lifesaving medical mechanical miracles.

As it came to pass, though, more COVID-19 patients have benefited from high-flow oxygen therapy than from mechanical ventilation. That’s great news in places where medical oxygen is cheap and easily available, but that’s always the case. We’ve seen recent reports of hospitals in India running out of oxygen, and even rural and remote areas of the developed world can find themselves caught without enough of the vital gas.

To meet the world’s increasing demand for high-flow oxygen therapy, the team at OxiKit has developed an open-source oxygen concentrator that can be built for far less than what commercial concentrators cost. By filtering the nitrogen out of the air, the concentrator provides oxygen at 90% or higher purity, at a flow of up to 25 liters per minute.

Oxikit founder Maher Daoudi and some of the technical team will join us for this Hack Chat to discuss the details of making oxygen concentrators. We’ll learn about how they work, what the design process for their current concentrator was like, and how they got past the obstacles and delivered on the promise of high-flow oxygen for the masses.

join-hack-chatOur Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, May 5 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.
Continue reading “Open-Source Oxygen Hack Chat”

A Simple But Effective High-Flow Oxygen Concentrator From Hardware Store Parts

To say that a lot has happened in the year since the COVID-19 pandemic started is an understatement of epic proportions, so much so that it may be hard to remember how the hardware hacking community responded during those early days, with mass-produced PPE, homebrew ventilators and the like. But we don’t recall seeing too many attempts to build something like this DIY oxygen concentrator during that initial build-out phase.

Given the simplicity and efficacy of the design, dubbed OxiKit, it seems strange that we didn’t see more of these devices. OxiKit uses zeolite, a porous mineral that can be used as a molecular sieve. The tiny beads are packed into columns made from hardware store PVC pipes and fittings and connected to an oil-less air compressor through some solenoid-controlled pneumatic valves. After being cooled in a coil of copper pipe, the compressed air is forced through one zeolite column, which preferentially retains the nitrogen while letting the oxygen pass through. The oxygen stream is split, with part going into a buffer tank and part going into the outlet of the second zeolite column, where it forces the adsorbed nitrogen to be released. An Arduino controls the valves that alternate the gas flow back and forth, resulting in 15 liters per minute of 96% pure oxygen.

OxiKit isn’t optimized as a commercial oxygen concentrator is, so it’s not particularly quiet. But it’s a heck of a lot cheaper than a commercial unit, and an easy build for most hackers. OxiKit’s designs are all open source, but they do sell kits and some of the harder-to-source parts and supplies, like the zeolite. We’d be tempted to build something like this just because the technology is so neat; having a source of high-flow oxygen available isn’t a bad idea, either.