Hey y’all! It’s Horatia (o Horacia as I am known here). I want to share both life details and more technical details in the same post, so bear with me. I’ll try to segment into paragraphs/bullets/pictures so it’s easier to follow.

Today we woke up again to the good ole’ rooster. I admit that it’s slowly losing its charm because it’s starting to sound less “quaint countryside” and more “snooze-less alarm” as the days go on…but I digress. We skipped breakfast and headed over to the Cantaro Azul headquarters early (okay, well 8 AM), where the three of us proceeded to devour an entire box of off-brand Frosted Flakes. At around 9:00, we settled in and started getting to work.

I had been feeling a little restless yesterday about what to do with my project. Today, however, I feel as if we made some real progress. Briefly, my project deals with the re-contamination of water via drinking vessels. The image below helps elucidate this need.

Even though water coming out of the Mesita Azul (a UV disinfection system) is clean, people will still end up drinking contaminated water for a multitude of reasons. The main ones we’ve been told are because community members tend to:

1. Rinse their cups in untreated water
2. Have poor hygiene habits that result in fecal contamination

We are trying to design an affordable device or module that is easy-to-use and will help reduce this re-contamination. 

A CAD of our end-of-year prototype is shown below. This prototype functions as a hand-powered, single-cup dishwasher that utilizes chlorine to disinfect the cups. The pump provides the water displacement necessary to cause water to shoot upwards and clean the insides of the cups (much like a barista and their pitcher cleaners).

With the help of Sophia and Su Chen, we were able to rebuild our most recent prototype using a bucket Sinead brought for us. Note that we did not bring concrete with us from the States, so we just weighed down the bucket with some old bricks we found. We also did not cut two holes in the bottom of the bucket (where water would ordinarily enter and drain), because we did not want to waterproof the device. We considered these deviations acceptable because the function of this prototype in country was to discover on a very basic level whether the concept was feasible (hand-powered or not, too much of a hassle or not, etc.). Below are two photos of our building. I have never prototyped in a more scenic location; the mountains in the background are just gorgeous.

Testing the Pump Prototype

Pros of the pump prototype

• Uses a small set amount of water
• Does not require connections to other devices
• Adds an air of novelty to washing

Cons of the pump prototype

• Resists the pull of the pump handle upwards
• Requires measuring of chlorine each time
• Uses a lot of effort to pump, especially multiple times

Questions/Ideas for the pump prototype

• Does WHO (World Health Organization) allow the use of liquid bleach in water?
• How would we make this easier to pump?
• Are there large enough pumps available that are food safe?
• Does the chlorine have a long enough contact time?

To be super realistic, this design is good in theory but is harder than washing the cup with soap and water, so what’s the point? I believe that it’s better because its a starting point for future design work, whereas the soap and water has basically reached its max ease-of-use. That being said, Cantaro Azul does not want a pump if possible because pumps are expensive. Therefore, we would need to come up with another way to washing the cups.

At this point we took a step back….and grabbed lunch. Really, we grabbed desayuno, but it was at 11:00 so we Americans considered it basically a lunch. We then proceeded to brainstorm about what else we could do to make the device more intuitive and easy to use. I went digging through how to DIY pitcher cleaners and didn’t find anything. BUT it did generate a new idea.

This new idea is directly inspired by the pitcher cleaners used by baristas (below). Rather than have a completely different system, we imagined having  a system that connected to the Mesita Azul. Essentially, if a user wanted to wash their cup, the could switch off the right hand side valve (which is where the garafones (5 gallon water jugs) are normally filled) and switch on the valve on the left.  The pipe would decrease on the left so that the water would flow through a stack of chlorine pills and then squirt upwards through small holes cut into the pipe. We also piloted the idea of having water flow in this manner in the video below. We also realized that if water pressure was too low, we really didn’t need the water to be spraying upwards, so we have a side design for water just flowing out.

A diagram for this design (as sketched out in the moment), is below as well. Note that I was writing in Spanish to better communicate to other people at Cantaro Azul what we were envisioning. Also note that we considered implementing a recycle stream of the water; however, we later eliminated that section of the design because it required a pump.

Testing Pitcher Cleaner-Inspired Prototype

We talked to Hector, Fermin, and Sinead about our device and got the following feedback.

Pros of the pitcher cleaner prototype

• Washes cups just by a turn of the handle
• Ensures clean water (connects to Mesita Azul)
• Requires no electricity or hand-pumping

Cons of the pitcher cleaner prototype

• Water in the Mesita Azul may touch the UV light (which would lower its lifetime) if valves are included.
• Pressure in the tube may not be high enough for water to hit the bottom of the cup when sprayed. Lowering the device to generate head may help, but would result in community members washing too low.

Questions for the pitcher cleaner prototype

• Is chlorine helpful enough to be worth the hassle and cost of adding it to the design?
• How useful is drying the cups beforehand?
• How bad are the cups in the first place? Do they really need to be washed?
• If you were going to build a separate module, how high would you be able to lift a garrafone? How low would you like to wash? Our answer to former was not high at all.
• Where is the contamination coming from?

Fermin suggested that we conduct a literature review, which would likely be more reliable than tests we collected in the field. We plan to look into these questions in more detail on Saturday. Again, this design is good in theory but is harder than washing the cup with soap and water, so what’s the point? We’re hoping that we can come up with something that overall can make community member’s lives easier, and therefore will be used.

Finally, I got a chance to talk to one of the volunteers who works in the field with the community members. She said that the reasons people don’t wash their cups properly is because they just don’t have that much water.

• They must go out and get their water (it’s not piped to their house), so it is a waste to use it to clean cups
• They must clean the cups because they leave them in the kitchen, so they tend to get dusty

We gather that our device would need to be water efficient and that it would optimally come with, or be, some sort of  storage device. It may be worthwhile to segment the communities into those with and without water, because having running water or not will make a large difference in regards to water use.

By then, everyone started leaving the office, so we headed back as well. We stopped at this hipster vegan cafe for dinner called te quiero verde. Classically, we forgot to bring enough cash, so we ended up running back to the apartment after we finished eating — grabbing money — and then running back to pay.  Worth it though, because their fries were to die for.

-Horatia