Week #45 – Finally Installing
I’ve skipped week #44 because I am missing two pictures I need. I will post it when I return to California next week. With this entry I am about a month behind with my posts. We are currently on week #49.
After some rough starts we finally got a filter into some houses. We have been challenged to find sand that meets the new times from CAWST, 100 seconds per liter.
These are the sieves we have using to find out what our distribution is for each source. The problem is that every time it rains the sand in the rivers changes. We are trying to find the most reliable source we can.
We chose the source that gave us a distribution with the highest percentage of smaller particles. To sieve the sand it needs to be dry so it is left in the sun before pouring it over the inclined sieve. This lets the larger particles roll off while the smaller ones fall through. We found that the higher the incline is the less course sand falls through.
Then we took that sand and sieved it again but this time with a fan blowing on it to blow away the smallest particles. Eventually we will start to bake the sand to remove the organics. For now though, this process consistently gives us times of at least 1 minute 30 seconds per liter.
The best part about working to 7pm is that I get to see some stunning sunsets. The pollution in La Ceiba always seems to dull them, or maybe it’s just the poor skyline?