Today was definitely a learning experience! The morning was spent working on filters and figuring out protocols. It was great; I love that we are trying to do everything (even testing) with local materials. At one point we even took a mini field trip to the Poly’s game center to borrow a ping pong ball for testing airflow. However, the afternoon we ran into a couple road bumps when we started working on the sieve beds.

To give a little background, there are two sieve beds in an oxygen concentrator. They both contain zeolite (aluminum silicate) which binds nitrogen and is used to filter out the nitrogen leaving only oxygen as the output. They work using a valve system with one sieve bed binding nitrogen while the other one is purging it’s contents. The sieve beds work great until they are contaminated with water (which usually happens due to bad or missing filters). Our goal is to figure out a simple and effective way to regenerate the zeolite in the sieve beds. In other words, we want to get rid of the water when the sieve bed has been contaminated.

Before we start to even go through the design process, we decided our first goal was to understand the sieve bed. We did some research on Monday and talked to Matt and found that there is a company that regenerates zeolite by heating it up for a long period of time and then placing the zeolite back into the sieve bed before it has cooled down completely.

Proving that this procedure works is the best place for us to start! Thus, today we decided to try to take apart a sieve bed. This seemed like an easy test, but I have started to learn that things are not always what they seem. Opening the sieve bed involves pushing down a spring and trying to pry open the top. This is done in the machine shop using a press to apply the proper pressure needed. Since there is a spring, potentially hazardous material inside, and we were using a large press: safety definitely came first! We were wearing masks and glasses during the entire process:

It is better to be over safe than sorry. Our first mistake was not applying pressure evenly. This caused the fitting on top of the sieve bed to become slanted and wedged into the cylinder of the sieve bed. Our second mistake was trying to fix the first mistake. We ended up applying too much pressure in a concentrated area which resulted in a broken fitting. The funny thing with the broken piece is that we still could not open the sieve bed and get to the zeolite. As a result, we had to admit our failures and go to Matt for more help. We eventually got the zeolite out! The entire process taught me a lot:

– Things are sometimes easier said than done
– Sometimes you need to experience failure to grow in the end and come out with more knowledge
– Sieve beds are definitely not meant to be opened up in a hospital setting
– Even after breaking something it can be difficult to open
– Just because something has a spring does not mean it will jump out at you  after a fitting is broken
– You get a lot of weird looks when you walk around the poly in a bunch of safety gear

So even though we were not successful at our first attempt to open the sieve bed, I know we will have much better luck next time and we learned way more then we ever would have if we succeeded the first time.