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mdalton · 21-12-2022, 06:18

Hi Bill & Others

A replacement QuenchSea arrived yesterday from the manufacturer. Here are my test results using simulated sea water about 35,000 ppm.

Pumping time: 9 minutes
Total strokes: 200 (my sedate pace)
Volume of output: 55 ml
TDS drinking water: 798 ppm
Pressure release valve setting: 45 - 50 bar
Water taste: acceptable
Leaks from QuenchSea: zero

The output volume implies one litre of drinkable water would be available in around 160 minutes. However my pumping pace was very sedate. In a real emergency situation it would be possible to produce double that amount in the same time.

Overall I think the QuenchSea is excellent value for money at around USD 130. Pumping is a two hands job unless the machine was secured to a solid surface. Use in a liferaft is possible although volumes would be restricted. Ideally a handle could be attached to the baseplate allowing a clam shell closing action with two hands.

Well worth keeping an eye on this product, buy one for your own testing and look out for design options that may be more suited to yacht and liferaft use.

Bill O · 21-12-2022, 08:16

mdalton,
Again thank you for reporting your findings.

Seemed like fairly good turn around to send you a new unit. The testing for this new unit was very similar to your first testing, yet now the TDS in the product water is nearly double of the first unit testing.

While still in the acceptable range, any thoughts why this occurred?

Wonder if you continued to use the unit that the TDS of the product water would be reduced. Also if the pressure is raised to 50-55bars, would that lower the TDS?

mdalton · 21-12-2022, 08:40

Hi Bill

Yes, I believe raising the pressure relief valve setting to filter at a higher pressure does reduce the TDS reading (as was the case with my first unit).

However the recommended pressure relief valve setting is 45/50 bar that makes the TDS under 1000 ppm and provides drinkable water at a higher rate of production.

Lemsteraak · 17-01-2023, 12:48

Interesting machine, I got a chance to try it out.

I used saltwater I got from Netart's Bay, here in Oregon, high salt content, no freshwater streams run into it.

QuenchSea is right to say give it at least five minutes of pumping to clear and clean the machine. I'd say give it ten minutes. The first fresh water had a slight oil tinge to it and had over 400 ppm TDS so I wasn't holding out much hope for the machine.

The results I received after a 15 minute session - 1 pint of fresh water with a TDS of 252. In comparison, my old lifeboat water maker produces half the water and twice the effort. The TDS is comparable. Taste test was good, didn't taste any salt.

The pumping method MDalton specified is similar to what I used. First open the "bleed" valve under to get the compressible air out when pumping. Then you can pump up to the 5 bar limit easily. The pressure relief valve will pop and bring the pressure down to 4 bars once or twice a stroke. The pump style can be leisurely, keep it at 5 bar and then let the pressure relief pop off to clear the brine. My thinking is to let the water flow through the membrane so I was pumping about 10 strokes a minute keeping the pressure high. If I pumped more, I didn't notice much improvement in fresh water flow. I was playing with the "bleeder" valve to release air so it released some water, I didn't notice any other leaks. I would recommend practicing in the cockpit as it can be wet.

Bottom line, it works, my leisurely style produced about half the QuenchSea quoted fresh water production. I just got some new membranes in so I'm curious to see if they have a higher volume.

tilaya · 22-02-2023, 13:37

Hi All,
got to try my QS today. Unfortunately I do have to delay presenting results.
The unit had a leak at the water entrance to the membrane containment.
I reported to QS.

The unit got a little bigger than it could be anticipated from the first promo pictures at the begining of the campaign. It hung of a backpack. Well it still be possible to hang it of a backpack, though it will not to be "overseeable".

For the purpose of water supply in emergencies. The QS does definitly not fit into a life raft like used on yachts.

CoVi
SY Tilaya

Thelo · 10-05-2023, 08:34

This company is coming out with a new product with a different approach. It's a capsule you lower to 300-500m and the water pressure forces sea water through an RO membrane producing freshwater. 1.5L per "drop". Interesting...

https://www.quenchsea.world/pages/reel

pbmaise · 10-05-2023, 09:03

Quote:

Originally Posted by Thelo

This company is coming out with a new product with a different approach. It's a capsule you lower to 300-500m and the water pressure forces sea water through an RO membrane producing freshwater. 1.5L per "drop". Interesting...

https://www.quenchsea.world/pages/reel

I like this idea. Very novel! Instead of doing a lot of work pumping you have a long long line to pull up.

A roll of fishing line this long weighs about 12 lbs. As sailors we should know never to wrap the line back over the spool because it will introduce a twist with every wrap.

It takes a lot of work to pull in a line this long if the vessel is moving. I was fishing once when a spool line fell overboard and I had to reel it back in. No one noticed until the line spooled out several hundred meters. The vessel was traveling at about 7 knots and the only drag on the line was the spool and the length of line. It felt like I was pulling in a fish weighing 100 lbs. Further, it will take a much longer line than 500 meters and a heavy weight to get it that deep. Therefore, I don't see this functioning unless the vessel is stopped and there is very little current.

AKA-None · 10-05-2023, 21:29

I’m confused
If the pressure on both sides of the membrane is the same then what pushes the water through?

Franziska · 11-05-2023, 00:19

The concept idea seems to be fantastic.

Yes it is work to reel it in, but so is creating water by a hand driven desalinator. That is much harder.
Beeing stationary would not be an issue on a liferaft.

Even if to big to fit into a packaged life raft it would be worth taking with you into the raft.
Even if it produces just half the intended capacity it would make survival possible for the person in the raft.

The big question is if it can be really made to work. "Aka" is right to be doubtful.
I cross my fingers for them.
They already have a product which seems to be designed so that it can be built much more cost effective than the competitive products while still working reasonably well.

BlueH2Obound · 11-05-2023, 08:34

Quote:

Originally Posted by AKA-None

I’m confused
If the pressure on both sides of the membrane is the same then what pushes the water through?

If the chamber being lowered is capable of withstanding pressure at that depth (500 meters would be in the neighborhood of 240psi) and the only way to equalize pressure would be for the ambient pressure at that depth to pass fresh water through a membrane into the interior of the pressure vessel, in theory, you could get fresh water out of it.

Of course, when you reel it back to the surface, the fresh water will try to "escape" again, unless there is a check valve. And after you get it back to the surface, you will need to vent off the ambient pressure from the depth it was down to . . .

**Pete7** · 11-05-2023, 08:46

Quote:

Originally Posted by BlueH2Obound

(500 meters would be in the neighborhood of 240psi) a

Bit more that that isn't it, say 725psi. I only managed 72m and that took 90 minutes to get back to the surface.

Pete

Bill O · 11-05-2023, 10:15

Interesting idea, but still question the realistic drop to 300-500M depth needed to make this work.
On a boat are you going to stop in the middle of the ocean for 5 min. to get 1.5L of water? Only if you were becalmed.
In a life raft, you are going slow/drifting so no problem on the speed. Where are you going to store that amount of line and device? Guess you aren't doing much and you could hand deploy/retrieve all that line, but would be a fair amount of work. If that was my only source of water, not sure I'd want to drop it down that far and hope it came back (nothing ate it or it didn't get snagged on something).
Again interesting concept.