carbon prefilter for watermaker

[CaptainRivet]

Hi all,


the membran of a watermaker is very sensitiv to all kinds of petrols and also chlorine. Why no one puts a carbon filter as prefilter inline for a watermaker to protect the membrane. it will also serve as a 2nd filter after the 30 mikron first filter and reduce furthermore the smaller the 30 mikron hard debris.


have a carbon prefilter anyhow on board to filter chlorine and other stuff out of the dockwater before filling it into the water tank. Could use this also as additional prefilter for the katadyn watermaker.
Why noone is doing that?

[Flysocal]

I and many others do it here in Mexico when using dock water to make water.

Not sure if Mexico uses chlorine in their dock water but we use the carbon filter just in case.

Adam

[CaptainRivet]

Originally Posted by Flysocal

I and many others do it here in Mexico when using dock water to make water.

Not sure if Mexico uses chlorine in their dock water but we use the carbon filter just in case.

Adam

you mean you use dock water as water supply for your watermaker?
not sea water?


what i meant using for the watermaker in the sea water supply as first prefilter a 30 Mikron and as 2nd prefilter a carbon filter to protect the membrane better. eg your fellow sailor in the bay next to you has a 2 stroke outboard which always leak. well if you get this in your membrane its quickly ruined, a carbon filter would protect it.

[Flysocal]

True about petrol in the water.

And yes, I use dock water as supply water to make water when in the slip. It works amazing... Sometimes 22gph on two pumps.

Adam

[SV_Sweet_Ruca]

Originally Posted by CaptainRivet

Hi all,


the membran of a watermaker is very sensitiv to all kinds of petrols and also chlorine. Why no one puts a carbon filter as prefilter inline for a watermaker to protect the membrane. it will also serve as a 2nd filter after the 30 mikron first filter and reduce furthermore the smaller the 30 mikron hard debris.


have a carbon prefilter anyhow on board to filter chlorine and other stuff out of the dockwater before filling it into the water tank. Could use this also as additional prefilter for the katadyn watermaker.
Why noone is doing that?

Great question! We have a carbon filter for the back flush, but only the paper filter on the inlet. Adding another carbon filter to the inlet would not be a great complication or expense.

On board this thread to hear a WM expert chime in.

[Marathon1150]

I'm only guessing but one downside of filtering sea water through a carbon filter before it goes through the water maker membrane could be that the carbon is quickly overwhelmed by the large number of suitably sized particles inherent in sea water. The carbon in the filter adsorbs particles, particularly organic particles by being sticky. When flooded with huge volumes of these as would be the case in sea water, the number of active adsorption sites will be reduced quite quickly. I am basing this guess on experience in a laboratory setting where activated charcoal is frequently used to remove certain compounds from solutions prior to further processing.

An activated charcoal filter would certainly be helpful but its lifetime would be very limited if filtering sea water and unlike the paper or plastic pre-filters typically used in water makers, would be difficult if not impossible to clean and reuse.

I clean our paper/plastic filters by hanging them over the side of the boat after a good rinsing as per Spectra's suggestion. This not likely to work for a carbon filter.

[Tomodore]

I was filtering dock water recently, not with my water maker but particle filter and carbon filter and uv treatment. The water smelled a bit of chlorine. I asked the local water maker expert about it and he told me in his experience carbon filters last about 6 months after the first use. I put a new filter in and problem solved. I didn’t use the old filter much but it was a year old. Heads up for using carbon filter for protecting RO membrane.

[pilott]

This is a great question.
Using a (relatively cheap) carbon filter to remove as much as possible before RO makes sense
I agree with Marathon1150 about the carbon filter being overwhelmed, but why not use a carbon filter as a 2ndry filter, after a standard pleated filter?

[Dirk01]

Originally Posted by CaptainRivet

Hi all,


the membran of a watermaker is very sensitiv to all kinds of petrols and also chlorine. Why no one puts a carbon filter as prefilter inline for a watermaker to protect the membrane. it will also serve as a 2nd filter after the 30 mikron first filter and reduce furthermore the smaller the 30 mikron hard debris.


have a carbon prefilter anyhow on board to filter chlorine and other stuff out of the dockwater before filling it into the water tank. Could use this also as additional prefilter for the katadyn watermaker.
Why noone is doing that?

Hi folks,

the most important thing to consider is, that a "completely filled carbon filter" (and you do not really know, when it's filled up!) let the bad things out in one go! Hence, it's VERY important to observe the manufacturers recommendations about the max. flow rate and the max. (added up) volume. Please kepp that in mind!
But, I thing it's a very good idea for (probably) contaminated water!
You give me a very good hint for an upgrade.
MANY THANKS!

[mitiempo]

Assuming one is using salt water to feed a watermaker there is no benefit I can dee to a carbon filter on the inlet side. The pleated 20 and 5 micron filters are all you need.

For flush of course a carbon block filter is needed.

[PLANET EXPRESS]

Make sure you use the right filter and flow rate as all water treatment facilities use chloramine not chlorine.
https://www.mawc.org/sites/default/f...ith_carbon.pdf

[sailorboy1]

seems to me that the extra membrane life would be so small that you probably could not even measure it.

If you harbour water is so fouled with gas etc that it is a foot plus below the water line and get sucked up onto the watermaker feed line, probably a better course of action is to not run it.

[Lepke]

I use a carbon filter before the membranes and another at the galley sink because I use a small amount of chlorine in the tanks. I also use a series of filters down to 1 micron. I make water year round and in fresh water when I can.

[sailorboy1]

Originally Posted by Lepke

I use a carbon filter before the membranes and another at the galley sink because I use a small amount of chlorine in the tanks. I also use a series of filters down to 1 micron. I make water year round and in fresh water when I can.

so you use a carbon filter in the raw water feed to your watermaker?

[lhuff35204]

If you plan on running your watermaker in a marina or harbor, an Oil/Water separator will help keep oil and gas pollution from entering your system. This will protect the membrane from irreversible damage.

https://www.spectrawatermakers.com/u...tor-filter-kit