Digital water purity tester before disposal?

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Grelko

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Do you think these would work well to test for any left over metals in solution?

After neutralizing, when all that's left "should" be clear salt water, would that mess up the PPM "TDS" reading?

Will it be accurate enough that you can dump it down the sink?

If these wouldn't be good enough, can someone recommend one for me?

It would be used before disposing solutions made of HCl/H2O2, Cl and SMB. The solutions will be neutralized with either sodium or calcium hydroxide. (Using the proper disposal methods on here. Copper, filter, iron, Ph 9 back to Ph 7, etc.)

http://www.ebay.com/itm/LCD-Digital-TDS3-TEMP-PPM-TDS-Meter-Tester-Pen-Stick-Water-Quality-Purity-kit-/192048883141?var=&hash=item2cb70165c5:m:mR3RPeWanUSFVKZixji2pZA

http://www.ebay.com/itm/US-Digital-Ph-Meter-TDS-Tester-Aquarium-Pool-Hydroponic-Water-Monitor-0-9999-PPM-/262755008703?hash=item3d2d6b40bf:g:HiMAAOSwnHZYSk2W

http://www.ebay.com/itm/New-HM-Digital-TDS-EZ-PPM-Meter-Tester-Water-Quality-Test-TDS-Monitor-/391661309545?hash=item5b30d54e69:g:l-IAAOSwDuJWu3BB I'm leaning towards this one because of the quality chart on the back of it, but I'm not sure if it calibrates properly vs salt water, to test for metals.


Also, after getting to the point of "salt water", if I decided to evaporate it, would it still smell like HCl, or lime?
 
TDS is Total Dissolved Solids (had to google it) and NaCl is included in it. The meter only goes up to 10 grams per liter so your solution would probably overwhelm it with the salt.

Göran
 
These would not work well, (if at all), for waste solutions. They are ohm meters designed to test the output of RO and ion exchange beds for water purifying. By the time you test the output from a purifying system the solids are almost gone.

They would be overwhelmed by the amount of solids from stock pot waste by several orders of magnitude.
 
g_axelsson said:
TDS is Total Dissolved Solids (had to google it) and NaCl is included in it. The meter only goes up to 10 grams per liter so your solution would probably overwhelm it with the salt.

Göran

I'm trying to find one that will bypass NaCl or KCl and only test for metals. No luck so far.

rickbb said:
These would not work well, (if at all), for waste solutions. They are ohm meters designed to test the output of RO and ion exchange beds for water purifying. By the time you test the output from a purifying system the solids are almost gone.

They would be overwhelmed by the amount of solids from stock pot waste by several orders of magnitude.

It would be used at the very end right before dumping it. The only thing left in solution should be salt water and maybe a trace of dissolved metals. There shouldn't be any solids left after filtering.

I'll explain this better. I'm trying to make sure that the solution is clean enough, before dumping it down the drain, that if I really needed to, I could add it to a fish tank or drink it even though it would be salty. ( Please do not ever try this)

I figured a water purity meter would tell me if the solution was clean enough, or if I still needed to work on it.
 
Dissolved salt or metals in water ARE solids.

These meters work by passing a current through the water, the more "stuff", (solids), in the water the less resistance to the current and the lower the ohms value, which these meters convert to a PPM readout with internal software.

In the water purifying business a reading of 18 mega ohms is a pure as it gets. Which means almost no measurable solids in the water. At that point the water is so pure it becomes a solvent that will eat the enamel off your teeth if you drink it often enough.

From Wikipedia; " Absolutely pure water has a conductivity of 0.05501 µS/cm and a resistivity of 18.18 Mohm•cm at 25 °C, the most common reference temperature to which these measurements are compensated. An example of the sensitivity to contamination of these measurements is that 0.1 ppb of sodium chloride raises the conductivity of pure water to 0.05523 µS/cm and lowers the resistivity to 18.11 Mohm•cm."

Refining waste water, even well treated, will still contain so much solids, (salts), that the reading would be millions of times lower resistance than what the meters are designed to measure. IMHO anyway, but I could be wrong.

Even if you got usable readings there would be no way to tell if the PPM was just salt, or copper, or some other metal. PPM is PPM with these meters reading it as a measure of current they won't discriminate between harmless salt and lead.
 
rickbb said:
Dissolved salt or metals in water ARE solids.

These meters work by passing a current through the water, the more "stuff", (solids), in the water the less resistance to the current and the lower the ohms value, which these meters convert to a PPM readout with internal software.

In the water purifying business a reading of 18 mega ohms is a pure as it gets. Which means almost no measurable solids in the water. At that point the water is so pure it becomes a solvent that will eat the enamel off your teeth if you drink it often enough.

From Wikipedia; " Absolutely pure water has a conductivity of 0.05501 µS/cm and a resistivity of 18.18 Mohm•cm at 25 °C, the most common reference temperature to which these measurements are compensated. An example of the sensitivity to contamination of these measurements is that 0.1 ppb of sodium chloride raises the conductivity of pure water to 0.05523 µS/cm and lowers the resistivity to 18.11 Mohm•cm."

Refining waste water, even well treated, will still contain so much solids, (salts), that the reading would be millions of times lower resistance than what the meters are designed to measure. IMHO anyway, but I could be wrong.

Even if you got usable readings there would be no way to tell if the PPM was just salt, or copper, or some other metal. PPM is PPM with these meters reading it as a measure of current they won't discriminate between harmless salt and lead.

It's all good, I'll most likely just clean it up, filter and evapotate it (I was looking for a quicker way). I'm not actually sure if I'm able to throw the salt with trace metals in the trash. I could always take it to waste management and ask them, or take the barren "treated" solution to the water testing station downtown to make sure it's safe enough to pour down the sink.

I should just distill it after getting back down from Ph 9 to 7 or better yet, pre-treat it through a carbon filter, distill using copper piping to remove any sulfer based compounds "like purifying wine or beer", leaving a pin hole at the top to let out any VOCs (volatile organic compounds), chlorine vapors etc, and re-distill it using a glass condenser. Then I actually could drink it :lol: ( no warning this time, it'd be pure water )

Or just reuse the distilled water for other solutions.

Technically salt should be a liquid https://www.quora.com/If-salt-has-been-dissolved-in-water-is-it-in-a-solid-or-liquid-state I'm not sure about metals though.

That's an interesting article about the 18M water "ultrapure". I couldn't seem to find any studies about it deteriorating tooth enamel, just a bunch of links saying it's fine to drink since it would mix with your saliva or anything else in your mouth and basically become "distilled water", then by the time it reaches your stomach, it would be about the same as tap water.

There are a bunch of youtube videos saying it's bad, but then again it's youtube.

On a side note, please accept my apologies. I am truly sorry if I sounded like an a**, I just REALLY enjoy reading/learning about everything I can.

The other day I was wondering... If the treated waste solutions aren't clean enough to drink "even though it'd be salt water", then why is it being released back into the environment. That's the main reason I was asking about using a "water purity meter" for my solutions.

Then I thought, well my vehicle leaks oil and radiator fluid, the trucking company down the road stinks like bandaids a lot of the time along with the semi's belching black diesel clouds, and there's a nuke plant a couple towns over releasing who knows what into the water and air, so an extremely minimal amount of dissolved metals in my left over (properly cleaned) solutions wouldn't really do much I suppose?

However, I will do my best to make sure that my solutions are clean as possible before disposing them down the sink, unless I evaporate them instead. Then I would need to figure out what to do with any left over dried materials.

Edit - spelling
 
Grelko said:
That's an interesting article about the 18M water "ultrapure". I couldn't seem to find any studies about it deteriorating tooth enamel, just a bunch of links saying it's fine to drink since it would mix with your saliva or anything else in your mouth and basically become "distilled water", then by the time it reaches your stomach, it would be about the same as tap water.

There are a bunch of youtube videos saying it's bad, but then again it's youtube.

Edit - spelling
[/quote]

No worries, I used to run a lab that used lots of DI water, half of what we made was 4 Mohm, the other half was 18 Mohn. The vendors of the equipment went on and on about not drinking it, it was in all their materials about how it was so "hungry" for ions that it would attack the enamel sucking out the ions and turn your teeth black.

edit to fix type-o's
 
Grelko said:
rickbb said:
Dissolved salt or metals in water ARE solids.

Technically salt should be a liquid https://www.quora.com/If-salt-has-been-dissolved-in-water-is-it-in-a-solid-or-liquid-state I'm not sure about metals though.
That's nuance. Rick is referring to dissolved solids in your waste stream.

Table salt is sodium chloride. Sodium is a metal.

Put those statements together, and even ordinary saltwater is still a solution containing a [dissolved] metal.
 
upcyclist said:
That's nuance. Rick is referring to dissolved solids in your waste stream.

Table salt is sodium chloride. Sodium is a metal.

Put those statements together, and even ordinary saltwater is still a solution containing a [dissolved] metal.

Thank you for helping correct this. For some reason I keep forgetting sodium is a metal (alkali metal group)
 
Yeah, it's not always obvious because they're so common. Same deal with potassium. Organic chemistry aside, most of the stuff in the left side of a chemical compound abbreviation (the positive ions) are metals: Ag2S, Fe(NO3)2, NaCl, KNO3, FeCl3, Li2CO3, etc. The primary exception is NH4+.
 
A Digital meter shows the same as any Analogue meter - a Reading (but much more convincingly).
Knowing what it means is quite another thing.

http://www.tdsmeter.com/what-is

Basically No : if a digital TDS reading says OK, it might easily be very much Not OK to dump the stuff down the drain.
 
upcyclist said:
Yeah, it's not always obvious because they're so common. Same deal with potassium. Organic chemistry aside, most of the stuff in the left side of a chemical compound abbreviation (the positive ions) are metals: Ag2S, Fe(NO3)2, NaCl, KNO3, FeCl3, Li2CO3, etc. The primary exception is NH4+.

I'll have to remember that, thank you. I've been reading/teaching myself about all of the different types of chemistry lately. I see most things starting with C or H.

aga said:
A Digital meter shows the same as any Analogue meter - a Reading (but much more convincingly).
Knowing what it means is quite another thing.

http://www.tdsmeter.com/what-is

Basically No : if a digital TDS reading says OK, it might easily be very much Not OK to dump the stuff down the drain.

Nice link, very informative.

Very true, if the "maximum" allowed was 500 PPM, you wouldn't know if it's 500 ppm of Pb, As or who knows what, maybe it's just NaCl. It doesn't actually tell you what's in it. I'd have to take it somewhere and have it tested to be sure.
 
Let's see if I finally have this correct. If I miss anything, please let me know.

Plus a few questions about certain parts.

This is just for an example.

Using cut Ram fingers only.

Hcl + H2O2, release Ram fingers "foils" from board.
Collect gold foils and remove board.

Solution is CuCl2 with Ni. "stannous negative"
Saturate with Fe to drop Cu and Ni.
Edit - Solution is now FeCl2.
Raise Ph to 2.5 using NaOH to drop the Fe. (approx 2.5)
Raise Ph to 9 and filter just in case traces of Fe, Cu or Ni are still in solution.
Lower Ph back to 7 with HCl and filter any precipitates.
Solution should be clear "salt water"

Salt water containing very minimal Fe, Cu and Ni goes down the sink. (Safe?)
Or
Evaporate till dry. (Or distill for reusable distilled water)
Dispose of salt "NaCl" containing very minimal traces of Fe, Ni and Cu into trash can. (Safe?)
Or
Continue heating until red, to turn trace metals into oxides, then into the trash can. (Safe?) "Ni fumes?"
---------------------------------

Dissolve gold foils in HCl+Cl

Solution is AuCl3? (or is it HauCl4?), with minimal Cu and Ni. "stannous positive"
Heat solution to remove Cl.
Drop Au with SMB "bringing traces of Cu and Ni". "stannous negative"
Collect gold powder.

Solution consists of HCl, [stt]Cl[/stt], SMB, traces of Cu and Ni. (possible Au, but extremely minimal) Edit#3 Cl removed by heating
Saturate with Fe to drop Cu and Ni.
Edit - Solution is now FeCl2.
Raise Ph to 2.5 using NaOH to drop Fe. (approx 2.5)
Raise Ph to 9 and filter, just in case traces of Fe, Cu or Ni are still in solution.
Lower Ph back to 7 with HCl and filter any precipitates.
Solution should be clear "salt water"

Salt water containing very minimal Fe, Cu and Ni goes down the sink. (Safe?) :?: What removes the sulfur after adding SMB?
Or
Evaporate till dry. (Or distill for reusable distilled water)
Dispose of salt "NaCl" containing very minimal traces of Fe, Ni and Cu into trash can. (Safe?)
Or
Continue heating until red, to turn trace metals into oxides, then into the trash can. (Safe?) "Ni fumes?

Edit - added

Edit #2 - What do you do with the left over iron and copper powders? I don't have the capabilities to melt them in to ingots/bars for resale.
 
For the waste stream side of things, in case no one has yet posted this link (busy atm): Dealing With Waste

My variation of the above:
Bucket #1 is the stockpot (cementation with copper)
Bucket #2 is the iron pot (cementation with Fe to drop Cu & other stuff).
Bucket #3 is a settling tank for the solids from #2. I'll eventually make a go at selling the solids as red brass.
Bucket #4 is neutralization (actually, raising to pH 9, then back to 7). Clearish liquid should be safe for disposal, solids go out with the trash after they dry out. I'm sure the trash guys that serve my neighborhood loved those 5 gallon pails of metal ;)

Edit to add: I've thrown out only 2 pails of solids since I started a bit over a year ago. I have about another pail and a half settling & evaporating. I suspect a lot of the bulk is more from the hydrated lime I use for pH adjustment. I tried to use another limestone product once when I couldn't find the hydrated lime locally, and it really sucked. Most of it ended up in the buckets as useless bulk.
 
upcyclist said:
For the waste stream side of things, in case no one has yet posted this link (busy atm): Dealing With Waste

My variation of the above:
Bucket #1 is the stockpot (cementation with copper)
Bucket #2 is the iron pot (cementation with Fe to drop Cu & other stuff).
Bucket #3 is a settling tank for the solids from #2. I'll eventually make a go at selling the solids as red brass.
Bucket #4 is neutralization (actually, raising to pH 9, then back to 7). Clearish liquid should be safe for disposal, solids go out with the trash after they dry out. I'm sure the trash guys that serve my neighborhood loved those 5 gallon pails of metal ;)

Edit to add: I've thrown out only 2 pails of solids since I started a bit over a year ago. I have about another pail and a half settling & evaporating. I suspect a lot of the bulk is more from the hydrated lime I use for pH adjustment. I tried to use another limestone product once when I couldn't find the hydrated lime locally, and it really sucked. Most of it ended up in the buckets as useless bulk.

I'm going to re-read that yet again after I post this reply. I WILL get it memorized properly.

I only have one bucket with a bunch of components dissolving in it. I also have 3 mason jars and a few gallon jugs of old solution that I need to dispose of. No stock pot right now, since I haven't had time to work on it for probably a good 6 months.

In an older thread I bought "lawn lime" ...do not use it for raising the Ph, the carbonates in it foam up WAY too much and it took half the day just to barely raise the Ph because of all the foam it produced. Needing to spray the foam down constantly just added more liquid to get rid of.

It was literally, add 1 "shot glass" of garden lime, spray foam down for about 5 minutes while stirring. :roll:

I bought a bag of slaked lime instead 8) (Calcium hydroxide)

Thanks for the help. Once I get to that point, I'll see if the scrapyard want's a bucket of "powdered" red brass.

upcyclist said:
I'm sure the trash guys that serve my neighborhood loved those 5 gallon pails of metal ;)

Anyone want a big bucket of rust? :D
 
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