Twospoons
International Hazard
Posts: 1400
Registered: 26-7-2004
Location: Middle Earth
Member Is Offline
Mood: A trace of hope...
|
|
Filtering large volumes of liquid
I recently found myself needing to filter about 6 liters of liquid, having just done some nickel plating and wanting to store the nickel dry as the
basic carbonate.
I quickly realized that slowly feeding it through a coffee filter, 1 cup at a a time, was going to be a long and tedious exercise.
So I came up with this:
1: attach some 4mm ID silicone tubing to the stem of a glass frit filter funnel ( I made an adapter using a 10ml plastic syringe and some vinyl tape
to seal it)
2: invert the funnel in the bulk liquid container
3: create a siphon to a receiving container
Its slow, but it means I don't have to babysit the thing for hours. I left it to do its thing overnight, and in the morning I had a tub with a thick
layer of damp nickel carbonate - ready for a rinse and repeat.
Helicopter: "helico" -> spiral, "pter" -> with wings
|
|
|
j_sum1
Administrator
Posts: 6487
Registered: 4-10-2014
Location: Limbo
Member Is Offline
Mood: Just got through yet another "take this job and shove it" moment.
|
|
Can you take a photo?
I am having some difficulty in visualising how the filtering works.
|
|
|
Pumukli
National Hazard
Posts: 730
Registered: 2-3-2014
Location: EU
Member Is Online
Mood: No Mood
|
|
Once I had to filter 180 liters of fairly concentrated (roughly 50%) ammonium nitrate solution. (I wanted to use it as a N source for my potatoes via
drip fertigation but could not get the ballast free, 100% soluble version at that time.) I used a big plastic funnel and a big sheet of coarse filter
paper - which was at least 30 years old at the time. And I used a Bunsen-clamp from my inventory to set the right drip speed of the solution by
squeezing a thin plastic tube. (I never needed that piece of thing either before or after this endevour.)
The whole process took 2 days (or 3? it was long ago) and the result was a perfectly clean solution that did not clog the drip tape in the end.
My process also relied on the "siphon effect". The solution was held higher (three regular pallets, one laying on top of the other, solution on the
top in a 200 liters plastic drum; dissolution was not trivial either due to the strong endotherm: the drum was icy even in the middle of summer!) On
the ground there were big plastic buckets/cans to catch the filtrate (and provide easy chang-over of the collecting vessels.)
Funniest part? Generating the necessary vacuum in the plastic tube to start the siphon. I used my mouth for this! As a side effect now I know the
taste of ammonium-nitrate solutions at least! 
|
|
|
Twospoons
International Hazard
Posts: 1400
Registered: 26-7-2004
Location: Middle Earth
Member Is Offline
Mood: A trace of hope...
|
|
Here's a couple of photos of the setup, one showing the siphon, the other showing the inverted filter funnel in the upper tank.
I also have a small peristaltic pump I could have used instead of the siphon, but I'm not in a rush with this one.
 
[Edited on 5-4-2026 by Twospoons]
Helicopter: "helico" -> spiral, "pter" -> with wings
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
