Hydrochloric Acid 36.2%

LadyInBed

LadyInBed

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Me - Zumerzet Boat - Wareham
montymariner.co.uk
Using it to decalcify heads pipes.
A few questions come to mind:
  1. Do the fumes rot curtains in the vicinity.
  2. I have poured about a quarter ltr down the anti syphon to heads outlet pipe, is it ok to leave it there for about three weeks.
  3. Will that be enough and long enough to clear a blocked outlet pipe.
  4. If I pour some down the anti syphon to (closed) seacock pipe, will it have any adverse effect on the seacock.
  5. Is there any other boat job that the acid can be used for.

Talk about diving into a job without doing any research! :dread:
 
If the pipe is that bad just replace it with proper Vetus Sanitary Hose. Four jubilee clips - job done.

Give the the acid to your missus to dispose of your body when she discovers the cost of the hose.
 
At that concentration, it is quite corrosive, so you need to be careful how you use it. Plastics and ceramics should be able to withstand it, but I don't think you should leave it in contact with metals for very long - in other words don't leave it in contact with metal seacocks for very long. The fumes are hydrogen chloride - not particularly corrosive as a gas, but very soluble in water, so if they come into contact with moisture you will get hydrochloric acid again. In a very dry atmosphere, your curtains are probably safe but if the weather is humid, you may get unlucky.

Hydrochloric acid at that concentration is going to work pretty quickly - you should not need to leave it there for weeks. I would expect that the acid and calcification would react to completion within an hour or two - after which you will either be left with water or acid in the pipes depending on whether you started out with an excess of acid or an excess of calcification.
 
LadyInBed said:
Is there any other boat job that the acid can be used for.
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Excellent for cleaning calcareous deposits off props, but on no account let it near aluminium. I'd be hesitant to use it in the concentrations you describe in the loo. Although rubber is largely unaffected by it in lower concentrations, it can corrode the springs in lip seals, such as above the piston in a Jabsco-type pump.
Otherwise +1 with chinita re new hose. HCl isn't the acid of choice for disposing of bodies: John Haigh used sulphuric, not that it did him much good.
 
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That is full strength HCl, assuming it follows the convention of percentage gas dissolved in water. I would not leave it more than about ten minutes. Concentrated acid will attack nitrile seals whereas dilute will not, at least in the medium term. I find that the reaction is mostly finished in that time anyway.

It will not attack brass/DZr/bronze seacocks.
 
The "fumes" should just be CO2; that won't rot anything. You might get a bit of HCl gas, but not very much. If you're concerned, take the curtain down. You shouldn't get chlorine given off, so bleaching the curtains isn't a concern.

Caution: CO2 is heavier than air, and collects at the lowest point. If you have animals, don't let them onto the cabin sole until you've thoroughly ventilated the cabin. People's heads are high enough that it's not likely to affect them, but animals operate closer to the floor!

The acid should be neutralized by the carbonate deposits pretty quickly, so I don't suppose it will matter if you leave it for a while. Once the acid is neutralized, it doesn't matter how long you leave it - it won't remove any more carbonate. ROUGHLY speaking, your 36% Hydrochloric acid will remove rather less than half it's weight of calcium carbonate, or about 0.2 of the volume. So, a litre of acid will remove ABOUT 200ml of carbonate - ROUGHLY.

I'd be worried about leaving it in contact with brass for a long exposure like that, and if ANY steel parts are exposed to it, it will corrode them pretty quickly.

It's great for cleaning propellers or the waterways of the engine. For the latter use, don't leave it too long and remove any engine anode before adding acid! Overnight in about the acid you've got diluted around 3 water to one acid will clean all the barnacle rings, tube worms or whatever from the propeller.
 
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P.S. if you are going to muck about with that stuff, have a pot of bicarb handy to allow you to rapidly neutralise any spills before they have a chance to do too much damage - to you or the boat.
 
AntarcticPilot said:
The "fumes" should just be CO2; that won't rot anything. You might get a bit of HCl gas, but not very much.
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Where would the CO2 come from? At that concentration, the fumes are indeed HCL gas. I've seen two patients in Intensive Care because they had used the stuff in a badly vented room. The gas solves in the lung lining, causing pulmonera edema ('water in the lung')
 
KellysEye said:
No need to use acid, close the through hull take the pipe off and bang it on the dock, the calcium will break up and fall out.
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I wish some of you people who gaily say, "Just take the pipe out, and bang it on the wall" would come and do mine. In total it is 6m long, although that includes 1.5m to a diverter valve, which is accessible. I reckon that the boat was built around the remaining 4.5m, and it would be a nightmare to replace.

I had problems with build-up last year, largely because of insufficient pumping. Jabsco recommend 7 pumps per metre. I was able to clear the totally blocked pipe, using a rotating wire drain clearing device from Aldi or Lidl, and Brick Cleaner from B&Q. The brick cleaner is dilute hydrochloric acid, but I don't know how dilute it is.

Prevention is definitely the best thing, so pump plenty.:D
 
thalassa said:
Where would the CO2 come from? At that concentration, the fumes are indeed HCL gas. I've seen two patients in Intensive Care because they had used the stuff in a badly vented room. The gas solves in the lung lining, causing pulmonera edema ('water in the lung')
Click to expand...

The CO2 comes from the reaction between the acid and the carbonate scale blocking the pipe ( dunno why someone earlier in the thread thinks its calcium ???)

I agree though the fumes from concentrated hydrochloric acid are very unpleasant, corrosive and "hazardous to health"

hydrogen chloride is very soluble ( only one of a very few common gases which will perform the "fountain experiment" q.v.) which means that any water or moisture about ( including in your lungs) will become corrosive hydrochloric acid.
 
KellysEye said:
No need to use acid, close the through hull take the pipe off and bang it on the dock, the calcium will break up and fall out.
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Interesting idea.
Now please tell me how to catch all the s h 1 t that got dumped into the pipe when it blocked!
What do you suggest for cleaning up the remainder of the s h 1 t that doesn't get caught ?

If I could get it to the stage where I can pump some water through then I wouldn't be so reluctant to disconnect some 'bottom end' connectors :)
 
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NormanS said:
I had problems with build-up last year, largely because of insufficient pumping. Jabsco recommend 7 pumps per metre. I was able to clear the totally blocked pipe, using a rotating wire drain clearing device from Aldi or Lidl.
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I like that idea
Prevention is definitely the best thing, so pump plenty.:D
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Its not done too bad, pipes have been in use for seventeen years!
 
LadyInBed said:
I like that idea

Its not done too bad, pipes have been in use for seventeen years!
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I don't know if this is any help to you, but my method was this: The boat was in the water. I was able to introduce the wire thing (snake) at a diverter valve. I closed the outlet seacock, and disconnected the hose from it. After a lot of effort with the snake, I got it right through the hose to the end at the seacock. The blockage was , as expected, at the lowest point on the hose, where "stuff" had settled. I then blew any remaining water out of the hose, using a dinghy pump, and then re-connected the hose to the seacock. I then poured in a couple of litres of Brick cleaner. An impressive amount of brown froth came out.

I have had no further trouble. As a precaution, during the winter, while ashore, I repeated the process, with both snake and brick cleaner, but got hardly anything, so I reckon that all is well. We now give the pump at least 42 strokes of flushing water. I'm sure that my toilet hose was brand new in 1992, but as its not exposed to sunlight, I don't expect it to deteriorate.
 
VicS said:
I agree though the fumes from concentrated hydrochloric acid are very unpleasant, corrosive and "hazardous to health"

hydrogen chloride is very soluble ( only one of a very few common gases which will perform the "fountain experiment" q.v.) which means that any water or moisture about ( including in your lungs) will become corrosive hydrochloric acid.
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Very unpleasant indeed. Hydrogen fluoride even more so; hence the recommendation to go nowhere near a recently burned out stolen car. Fluorinated flame retardants are widely used in the cable insulation, when burn they result in HF which will be present in any water around the car.

Even the vapour of a saturated solution of oxalic acid seems to cause irritation; strange really, as oxalic acid is a solid.
 
When I fitted a vent in my outlet pipe I scraped out some of the deposit. I did tests to see what dissolved it best: Hydrochloric, Oxalic, Phosphoric, and kitchen scale remover. Bottom line was that after two weeks, none of them had made a huge difference. I brought some scale home to repeat with more accurate measurements, will let you guys know when done.
 
nigelmercier said:
When I fitted a vent in my outlet pipe I scraped out some of the deposit. I did tests to see what dissolved it best:
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Hydrocloric, on the recommendation of Vic, or it might have been Vyv, in a previous thread.

Already done the test, my test piece was the pump rod as it had a calcium build up over the nut holding the plunger seal in situ.
Fizz fizz bubble bubble and it was as clean as a whistle in ten mins.
 
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