R.O. water filter install question

[dLj]

An example of internet information is here, where a system that looks exactly like the PO's is discussed. They claim only a 20-30% recovery rate for these systems.

https://extensionpubs.unl.edu/publication/g1490/2014/html/view

Mark

That's a nice summary!

RO systems are complicated if one is actually looking for a specific output. And, as I said above, you really need to know your feed stock chemistry to build the correct system.

dj

 

[dLj]

actually, it doesn’t answer my question but rather poses a different one. I’d still like to hear if anyone else has any actual experience.

to your question about analytical results, absolutely yes! The EPA lab in Atlanta does my analytical chemistry and bacterial/viral analyses. Quantifying waste volume is pretty simple as I am a chem engineer and lawyer (don’t hold the latter against me). Been doing this for years with other systems as well during the time in my career when I worked at EPA. While I understand your skepticism, it is misplaced.

Well perhaps your lawyer side (I'm not holding that against you - I've just spent way too many hours in court rooms seeing how lawyers like to direct discussion to a conclusion by ignoring specific facts that don't support their case) forgot to read my post above this one where you say I didn't answer where I did in fact answer that question. you are welcome to go back and look

Glad to hear you do chemistries - so what is the delta change from feed stock to RO output running a 1% waste? What constituents are you removing and at what levels of removal? What are you using for pre and post filters, if any?

I'd really welcome seeing the complete chemistries of your feed stock and output water.

dj

 

[Don S/V ILLusion]

Well perhaps your lawyer side (I'm not holding that against you - I've just spent way too many hours in court rooms seeing how lawyers like to direct discussion to a conclusion by ignoring specific facts that don't support their case) forgot to read my post above this one where you say I didn't answer where I did in fact answer that question. you are welcome to go back and look

I did look. Need I remind you what you said?

”The only experience i have is on a commercial scale producing strictly defined high purity water used in medical applications.
So I'd have to say pretty much hypothetical from my side in this conversation.”

As to the data, you are welcome to come down and look at the reems of data and records I have accumulated which is far too voluminous to replicate here.

 

[dLj]

I did look. Need I remind you what you said?


As to the data, you are welcome to come down and look at the reems of data and records I have accumulated which is far too voluminous to replicate here.

A simple summary of incoming chemistry and outgoing chemistry would be beneficial. What specific species are you best able to remove with your method, what does not get removed, what percentages are you dropping in what specific species that makes your water "better" - s simple summary would be great.

It would also be beneficial to the conversation. Water chemistry in Florida is not going to be the same in LA.

As Richard Feynman once said, "if you can't explain it simply, you don't understand it."

But I'd be delighted to take a look at your data. Send me a PM of how to do so ...

dj

 

[colemj]

I don't think any water quality test data are necessary to answer the question about recovery rates. I've spent time reading in general, and looking at manufacturer specs specifically, and I cannot find a single household RO unit that does better than 60% recovery rate. Most are lower.

So either I'm stupidly missing something that should be generally noticeable, or the 99% recovery system on Illusion is not a typical household RO unit. Perhaps an ion-exchange one instead? I do know from direct experience that ion exchange systems have very high recovery rates.

Mark

 

[Hello Below]

Been doing this for years with other systems as well during the time in my career when I worked at EPA.

I never drilled down into the references but this EPA website throws a little light onto the discussion.
EPA - Point-of-Use Reverse Osmosis Systems

 

[colemj]

I never drilled down into the references but this EPA website throws a little light onto the discussion.
EPA - Point-of-Use Reverse Osmosis Systems

From that link: "Some inefficient units will generate up to 10 gallons of reject water for every gallon of treated water produced. In contrast, point-of-use RO systems that earn the WaterSense label must demonstrate that they send just 2.3 gallons of water or less down the drain for every gallon of treated water they produce."

Returning 0.01 gallon to waste for every gallon produced does meet the definition of "WaterSense" <2.3 gallons, but seems a stretch that they thought this was even possible.

Mark

 

[Don S/V ILLusion]

A simple summary of incoming chemistry and outgoing chemistry would be beneficial. What specific species are you best able to remove with your method, what does not get removed, what percentages are you dropping in what specific species that makes your water "better" - s simple summary would be great.

It would also be beneficial to the conversation. Water chemistry in Florida is not going to be the same in LA.

As Richard Feynman once said, "if you can't explain it simply, you don't understand it."

But I'd be delighted to take a look at your data. Send me a PM of how to do so ...

dj

That’s insulting!

where did I say I couldn’t explain?
what I did say is that the data consists of many documents and that you PM me if you really want to know the minutia.
Nothing thus far.

If you do ask, please apologize first as I‘m not really inclined to take the time scanning documents and writing a summary for you.

 

[dLj]

That’s insulting!

where did I say I couldn’t explain?
what I did say is that the data consists of many documents and that you PM me if you really want to know the minutia.
Nothing thus far.

If you do ask, please apologize first as I‘m not really inclined to take the time scanning documents and writing a summary for you.

Well no insult was intended. Apologies if that's how it came across.

It would be great if you could dispel all of the documents everyone has posted to the contrary to what you are claiming. I don't see a reason why you wouldn't want to post a simple summary to the group when everyone here has been scratching their heads with how it could be possible to have only a 1% waste when all documents, and direct experiences as not supporting that statement. But you should be ready for some probing questions. Some of us have a fair bit of experience with water treatment.

dj

 

[Don S/V ILLusion]

Well no insult was intended. Apologies if that's how it came across.

It would be great if you could dispel all of the documents everyone has posted to the contrary to what you are claiming. I don't see a reason why you wouldn't want to post a simple summary to the group when everyone here has been scratching their heads with how it could be possible to have only a 1% waste when all documents, and direct experiences as not supporting that statement. But you should be ready for some probing questions. Some of us have a fair bit of experience with water treatment.

dj

I’m relating my experience. It’s not a “simple summary” but rather a series of documents tabulating years of data which can only be interpreted in light of many variables like input water source, quality, level of contamination, pressure and flow rates, yield fractions, membrane pressures, etc… you couldn't conceivably interpret absent a thorough understanding of the variables and conditions.

And to paraphrase your own post, you didn’t read what I actually wrote about the variables in quantifying waste percentage.

 

[dLj]

I’m relating my experience. It’s not a “simple summary” but rather a series of documents tabulating years of data which can only be interpreted in light of many variables like input water source, quality, level of contamination, pressure and flow rates, yield fractions, membrane pressures, etc… you couldn't conceivably interpret absent a thorough understanding of the variables and conditions.

And to paraphrase your own post, you didn’t read what I actually wrote about the variables in quantifying waste percentage.

It's been my experience that when a very complex issue arises that would be impossible to summarize in simple terms, that what is called "envelope" analysis can often be very useful.

This is where one takes the worst case and best case showing the "envelope" within which the particular subject resides. Certainly this by its nature misses a lot of the subtleties but can provide a method that makes it easier to understand.

So how about you take a worst case feed water source, show what's needed to produce your desired output and then do that for a best case scenario? That way the range over which you are stating you get about a 1% waste water discharge can be shown. How does this sound?

dj

 

[Don S/V ILLusion]

It's been my experience that when a very complex issue arises that would be impossible to summarize in simple terms, that what is called "envelope" analysis can often be very useful.

This is where one takes the worst case and best case showing the "envelope" within which the particular subject resides. Certainly this by its nature misses a lot of the subtleties but can provide a method that makes it easier to understand.

So how about you take a worst case feed water source, show what's needed to produce your desired output and then do that for a best case scenario? That way the range over which you are stating you get about a 1% waste water discharge can be shown. How does this sound?

dj

its not complexity which constrains summarizing efficacy. If the only thing which confounds you is the water/wastewater ratio, it’s simple. In fact, I think I already did that summary when I said that with sea water, the waste fraction can be significant but with ’clean’ water, it’s trivial. Is there something unclear about that “envelope analysis”?

This is getting tedious. Believe it; don’t believe it. it matters little.

If I looked through piles of paper, it would show precisely what I related my experience to be.