what type of screen for preparing fresh sand?

[Guest]

#646

Hi, I\’m in the process of building a Biosand filter for use with our shallow well (surface water) in Prescott, AZ. We have a dry creek with plenty of sand and I\’m trying to find the correct type of screens to sift out .15 to .35mm sand. I\’m not having much luck salvaging the right type of screen, either it\’s window screen or mosquito netting which is too coarse or cloth which is too fine. How are people all over the world getting the correct sand size? I plan on building more of these for our neighborhood if all goes well and would be willing to buy or order screens, but salvaging would be the very best. Any ideas? Thanks! -Jesse

[Guest]

#647

If I do buy sieve screens (which seems the most reliable way to get the right sand grain size) What is the least expensive reliable option? The sieves I\’ve seen on the internet seem to cost $40 US Dollars each. This is cost prohibative. Are there inexpensive sieve sets I\’m just not finding? This is the only missing link in our biosand project, Help! Thanks -Jesse

[bbuzunis]

#648

In Nicaragua we looked for fine relatively uniform sand. I basically picked the sand up and looked at a few grains on my thumb nail to guess the size was in the 0.1-0.2mm range. We took it out of the local river bed.

Even in our lab experiements we never went out and found true filter sand which they use in most water treatment plants. What we did is went down to the local landscape supply yard. My experience has been that the system is quite robust in terms of sand. Of course the finer the better.

We used window screen mainly as a first step to screening out any organic debris. Once we did that we spent some significant amount of time rinsing the sand out before installing it into the fitlers.

Cheers

—————————–
B. J. Buzunis, P.Eng