Your Thoughts On Using Condensate?

nibs

We are currently using about 12 fairly large batteries between trucks, RV's and electric tractor.
Anyone thought about using boiler condensate instead of distilled water to top up batteries?
Right now we are collecting our condensate in a bucket and chucking it out twice a day.
Nearest store that sells distilled is about a 15 mile round trip.
Your thoughts please.

Jamie Hall

I presume this is process condensate and not heating? It might work, but before you do it have it checked for total dissolved solids at least -- it must be very low or close to zero, or your batteries will not be happy

Jean-David Beyer

In some locations, people are required to run their condensate (from gas fired mod-con boilers) before discharging it into the environment. If you are going to use this in lead-acid batteries, the acidity will probably not matter much. But the condensate will have a lot of other stuff that went into the hot side of the heat exchanger and with mine, any condensate that happened in the exhaust pipe (that runs back into the boiler) and any bugs that wandered into the collection part of my pump that pumps the stuff away. So you might want to at least filter it to get the solids out. The dissolved solids will be an additional problem. I do not know a good way (reverse osmosis filter perhaps) that is not a pain to use in small quantities. You probably do not want to get a licensed water still to purify it.

Leonard

Given cost of bats I wouldn't just on general principles.

Think I'ld just buy bunch of jugs of DW on your next trip. Think it stores well.

Ma had some DW in a plastic gallon jug in celler for her steam iron for ironing clothes. It was opened 30+years old and cap put back on tightly. It still looks clean and clear as day 1. Just don't put any water back into jug, might contaminate it or introduce bacteria than might grow.

I assume boiler condensate is the steam return line from radiators , comes out of a steel pipe, opportunity for rust to be in it maybe Rust is an oxide , so might not be a problem, but I don't know the chemistry of what acid will do to it. Might not reduce it to a metal.

ChrisJ

I don't think he means condensate from a steam boiler.

Air conditioner? Dehu? Condensing boiler?

nibs

Condensing boiler.

Zman

Distilled water is used because it has a normal PH, TDS and chemistry. Condensing boiler condensate is the exact opposite.
I would use tap water way before using boiler condensate.

Leonard

Condensing boiler....I say no to using it's condensate.

Potential for all kinds of junk in that. Likely acid from CO, maybe nitric acid from NOx, particles, ash, rust, you name it. Likely a bit of steel dissolved in the weak acids.

Don't know what the alternate acids would do , but do you want to experiment with a $100-200 bat x12 ?

Other issue is if bats are using water they are likely charging at too high a voltage. Ideal charging voltage varies with temp, higher in cold.

nibs

Uncle.............. Distilled H2O only from now on.
It pains me to throw out crystal clear slightly acid water and then pay for water to use in batts.

ratio

You could …distill your own…

Jamie Hall

May I second @Leonard 's comment? Check your charging rates and charging controller. If charging rate is too high, the batteries will use water -- a lot more than they should.

nibs

Thanks all, none of my batteries has an improper need for water, but the ones on the tractor get used pretty hard. All my batteries have appropriate controllers or chargers driving them.
The water loss on the 4 golf cart batts for the tractor amounts to about 1 gallon per year. Have lived off grid using battery power for a total of 23 years, 8 on my sailboat and 15 in my motor home, not counting the winters spent camping in Mexico in smaller RV's , my water usage is far from excessive, but I just love that clear boiler condensate and hate to bucket & chuckit.

nibs

PS, my battery life appears to be about 10 years in the motor home, and about 4 years in the tractor, 4/6 years in cars and trucks. A pretty good indicator of reasonable charge/discharge rates.

Solid_Fuel_Man

Just for fun I dipped a litmus strip in my untreated mod/con's condensate. PH of 4.

I duy distilled water at Walmart for 89cents a gallon. Use it in batteries, mixing with antifreeze etc.

ChrisJ

Solid_Fuel_Man said:

Just for fun I dipped a litmus strip in my untreated mod/con's condensate. PH of 4.



I duy distilled water at Walmart for 89cents a gallon. Use it in batteries, mixing with antifreeze etc.

Sulfuric acid has a PH of close to 0, no?

Leonard

It's not the ph but what's in the water that worries me?

ChrisJ

> @Leonard said:
> It's not the ph but what's in the water that worries me?

Agreed.

Leonard

Boiler exhaust condensate will be acidic from steam and heat in exhaust interacting with CO, CO2, SOx and NOx to make acids( low ph). Likely will dissolve a little iron out of heat exchanger if it's not stainless.

Acidic condensate is why they sometimes run it thru a box of marble rock chips to neutralize it so it won't eat a metal drain pipe long term.

Jamie Hall

Lead acid batteries are actually pretty fussy about water quality. Ideally (right...) the water will not have much of any ionic content -- most easily, but not exactly measured by TDS -- other than the sulfate radical (SO4 -2) -- which will, as @ChrisJ said, give a very low pH, depending on concentration. It's that sulfate radical interacting with lead which gives the battery its storage capacity. Other ions and radicals ether interfere with that reaction -- or simply show up as a high to medium resistance short circuit inside the battery, causing it to self-discharge over time.

nibs

Years ago bought an electronic desulfator, and also tried adding EDTA to LA batteries to stop sulfation. Did not give it a true test, got busy with other things.

Leonard

I've read that lead acid bats are chemically very fragile. Get the chemistry off or voltages too high or low and they have a short life.

Still think if your adding water then your charging voltages are too high. Make it high and it rips water apart to H2 and O2. Think I read difference between normal charging and gassing is ~ 1 VDC. And need to adjust charging voltage with temp. In the 60's cars voltage regs were not temp compensated so needed to adjust them for summer and winter temps, at the very least.

I had an old car bat that wouldn't start a car anymore. I put it in my house alarm system. set the float voltage at ~ 13.6 VDC and marked water level. Some 8 years later when alarm said bat was bad the cells were only down 1/4 to 3/8 inch , 1/2 inch max at one bad cell. Water was still over all the plates.

ChrisJ

I've never had to add water to a car battery either.

But it has occurred to me that there must be some difference between the use of a typical lead acid car battery that's barely discharged and a "deep cycle" type battery.

I'm assuming it also depends on how fast you want it charged.

I think all of my vehicles since 2012 have been AGM though.

nibs

@ChrisJ , you are exactly right, the batts that use most water are on the tractor and on the RV's house side, these are deep cycle and get worked much harder than a car/truck batt. We still get excellent life cycles from them, which is the main criteria.

Solid_Fuel_Man

I think the bottom line here is this:

Even though that acidic condensate water looks nice and clean it is not! Batteries need not have anything added to them other than pure water as that is what was lost in the first place.

jumper

ratio said:

You could …distill your own…

Good idea. There are other uses for pure H2O besides batteries. Also I believe the correct density of battery acid/water depends on your altitude? And what happened to sealed batteries?

Leonard

At the lab we had pure water after it went thru continuously recirculating water polishing system. Meter continuously monitored it's conductivity ...... was ~ 18.7 megohm water.....VERY pure, nothing else in it. At that purity it needed plastic pipes, told if used metal tubing it would slowly dissolve ions out of it reducing it's resistivity.

Likely minor but cast iron in boiler contains other elements besides iron and carbon. They are in very low % and are added for castability and machinablity. But as acidic condensate slightly dissolves cast iron or other metals in system those atoms will be in the condensate too.

I think of condensate as sewage, not something to drink or use.

nibs

@Leonard said
"I think of condensate as sewage, not something to drink or use."
-------------------
Anytime we can make good use of something from the waste stream, we win.
I grind up Styrofoam waste and mix it with cement to make a low strength insulated light weight concrete, it works well and takes Styrofoam out of the waste stream.

Leonard

Ok for a floor I guess, topped off with layer of 100% cement for smoothness if exposed.

Without tests, I would be reluctant to use a high % Styrofoam loaded cement as a load bearing cellar wall, wall is similar to a structural collum. Under load it slightly bends outward at ~ middle height, like a violin string. Material strength is what keeps it from snapping.

Interesting idea though, What % loading of Styrofoam do you use?

Larry Weingarten

Hi, You might want to have a look here: https://www.rastra.com/#
Yours, Larry

nibs

@Leonard, we use styrocrete in walls only as a non structural filler, and depending on expected load and insulating value my mix is normally 1 cement, 2 sand maybe 3 or as high as 9 ground Styrofoam by volume, plasticizer and a shot of dish soap to "wet the water".
Engineering tests have shown that 'styrocrete' has a low compressive strength but has almost the same torsional strength as normal concrete.
My experience is that 2" pavers stand up very well using 5 parts styrofoam, corners crumble a little but no damage from freezing used outside. It is used extensively in Europe. California allows it 2R per inch but does not mention the mix ratio.

Leonard

WOW 69-75% Syrofoam, that's high loading. But you'ld need that so thermal path thru cement was long and narrow, otherwise likely not much improvement in insulation factor

I'ld say why not just use 100% styrofoam then 100% cement layer, but I'm guessing the styrofoam is ~ free.

Might consider adding insecticide to the mix, then layer of 100% cement. I hear carpenter ants like to burrow thru and live in 100% styrofoam underground.