Polyphosphate filters and Water Softeners 1

[GeorgioEng]

Hello everyone, Iam very happy to meet you. I have the following considerations and your help will be very much appreciated.

At the moment in my house I have a double array of filters in my central water supply pipes, a polypropylene filter for small particles and a Polyphosphate crystals filter for anti-scalling. So far, so good.

Currently, we have installed in our bathroom a steam generator for various therapies etc. The distributor and installer of the machine we bought, installed a blue tank with softening resin prior to the steam's generator water input in order to prevent machine issues with hard water.

What I would like to know is if the polyphosphate filter is working against the water softener. Do they have the same principle of operation? Is it bad to have both of them?

Thank you once again,

George

 

[PEDARRIN2]

Polyphosphates form a chelate with the hardness ions (they surround it in such a way no scaling occurs) - but do not get rid of them.

Softening exchanges the hardness ions with other ions that do not form hardness.

When steam is generated, this will typically stop the chelating and hardness will form on the generator. With softener, there might be a slight "residue" that will build up but is generally removed by wiping down the generator.

Having both will not be an issue.

 

[bimr]

People feed phosphate into water with the hope that it will eliminate corrosion. Unfortunately, it is more hope than science. It is considered a "seat of the pants" treatment, like for instance, that your car runs better after you have a car wash. You will not find an empirical evidence that phosphate works. It takes a significant amount of phosphate to work and nobody adds a significant amount of phosphate. A more effective approach to corrosion prevention is to increase the pH rather than inject phosphate.

If you have extremely hard water, the water softener will tend to make the water more corrosive.

If you have a water softener and it is properly sized; the water softener will remove essentially all of the hardness. That means the phosphate will not work at all.

The water softener should protect the steam generator. If you are having a problem with water corrosion, ask the supplier if the pH can be increased. Higher pH's will lessen corrosion. Throw the polyphosphate crystals filter in the trash.

 

[PEDARRIN2]

I would hardly say polyphosphates are not science based - unlike certain other "electromagnetic" versions. It definitely has its limited applications.

And, yes the polyphosphate would be useless after the ion exchange. But I have found a use for the polyphosphate version - when the required flow rate is too small to meet the flow/sf or flow/cf channeling minimums. Oversize a ion exchange softener and the flow basically goes through the middle of the bed without ever touching (mostly) the outer extents. So the innermost media will soon be exhausted and you have hardness breakthrough while the outermost media is still mostly usable.

 

[GeorgioEng]

thank you so much for your feedback. I undrestand quite well everything you are saying.

I could throw the polyphosphates crystal away (as @bimr suggesting) but, the purpose of these crystals are to "prevent" scale build-up (in the entire pipes infrastructure and not only the generator) by forming compounds (as I understand) with Calcium and Magnesium Carbonates. I would probably in the future alter the crystals with an entire-house water softener but not soon. Thats the first part.

At the second part, will the small and dedicated water softener for the generator do its job by de-ionising the Calcium and Magnesium Compaounds formed previously with the Polyphosphate?

Finally, will it be OK for us (the residents of the house) to inhale the steam generated, from the specific treated water?

 

[bimr]

I would hardly say polyphosphates are not science based - unlike certain other "electromagnetic" versions. It definitely has its limited applications.

The point that I was making it that application of phosphates is an art and frequently off the mark. You can't put 1-5 mg/L of phosphate in a water and expect it to do anything. pH control is the proper technique when one is trying to make the water less corrosive.

 

[bimr]

thank you so much for your feedback. I undrestand quite well everything you are saying.

I could throw the polyphosphates crystal away (as @bimr suggesting) but, the purpose of these crystals are to "prevent" scale build-up (in the entire pipes infrastructure and not only the generator) by forming compounds (as I understand) with Calcium and Magnesium Carbonates. I would probably in the future alter the crystals with an entire-house water softener but not soon. Thats the first part.

At the second part, will the small and dedicated water softener for the generator do its job by de-ionising the Calcium and Magnesium Compaounds formed previously with the Polyphosphate?

Finally, will it be OK for us (the residents of the house) to inhale the steam generated, from the specific treated water?

In a water distribution network, the goal is to adjust (higher) the pH so the water has a very slight tendency to scale. That minute amount of scale protects the piping from corrosion. Higher pH levels will make the water have a higher tendency to scale. Lower pH levels will decrease the tendency to scale which makes the water corrosive. The Langelier Saturation Index explains this concept.

langelier

A water softener removes the calcium and magnesium ions, replacing the calcium and magnesium ions with sodium ions. This water softening process tends to make the water more corrosive, especially when the water has elevated hardness levels. The scaling elements present in the raw water have been removed with water softening.

The steam generated will be safe for the household. Not sure of the device that you are using, but one would expect that you would not want to leave the steam device unused and damp where there is a possibility of creating the conditions that encourage mold and mildew.

 

[GeorgioEng]

Regarding the generator,there is an automatic discharge valve that discharges the water remaining in the machine to the sink whenever the last one shuts down, that's regarding the mold.

I see your point and why you are insisting with the pH. It's probably the best and most professional way on how to process the water in an installation. In my case, at least at the moment, I do not care so much to have the perfect quality since many years now we are drinking bottled water.

The issue for me now is mostly psychological and it has to do with whether or not the (poly)phosphates burden the steam I will breathe and not so much my appliances wear out. Are there any evidence on these? I mean how do I know the water is OK to be boiled and produce steam which I and my family going to inhale?

 

[bimr]

The issue for me now is mostly psychological and it has to do with whether or not the (poly)phosphates burden the steam I will breathe and not so much my appliances wear out. Are there any evidence on these? I mean how do I know the water is OK to be boiled and produce steam which I and my family going to inhale?

Steam generators heat the raw water causing the water to evaporate. The evaporated water is pure water with no salts. The remaining salts in the raw water stay in the steam generator (salts consisting of calcium, magnesium, phosphorus, sodium, etc.). Steam generators have some type of blowdown of the remaining water to prevent these salts from concentrating and forming crud in the generator. The salts are discharged to waste.

The steam consists of pure water and you should have no concerns about breathing it.

 

[GeorgioEng]

Dear friend, thank you so much for the time you dedicated on me.

I am a person that keeps scratching on various matters since I would like at least to understand (since I don't have the background to fully comprehend) all the parts of an installation.

Even the dealer I got the machine from wasn't able to explain the basic and core difference between the polyphosphates and a water de-ioniser even if he sells both of them.

As for the "steam consisting of pure water" I sure doubt it, since there are always some spots (probably salts) on the surfaces or I am fully wrong and they are from other sources of water and not the steam, since we are talking for a bathroom... And yes! There is a sediments cup at the downside of the steam generator, probably it is the same as the blowdown that you mention.

 

[bimr]

As for the "steam consisting of pure water" I sure doubt it, since there are always some spots (probably salts) on the surfaces or I am fully wrong and they are from other sources of water and not the steam, since we are talking for a bathroom... And yes! There is a sediments cup at the downside of the steam generator, probably it is the same as the blowdown that you mention.

The steaming consisting of pure water is the same as boiling a pot of water on your stove or using a humidifier. The salts don't evaporate, that why the dehumidifier cruds up.

 

[PEDARRIN2]

I think sometimes in steam generation, the fairly chaotic formation of vapor bubbles also generates tiny liquid water droplets that get carried into the air by the steam. These droplets are still "liquid" so can still have dissolved ions in solution. They land on other surfaces, then totally evaporate, leaving the hardness (scale) behind.

 

[MedicineEng]

There is always carry over of liquid droplets with the steam in this type of steam generators. This carry over takes the water and the dissolved solids with it, like Pedarrin2 referred above
The only way to overcome it would be to slowly boil the water, or have a large distance between the steam generation and the actual steam outlet, but then most probably you wouldn't have much of a steam room due to thermal losses.