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Re: Again with flux removal

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Jeff Liebermann wrote on 5/26/2017 4:56 PM:
> On Fri, 26 May 2017 14:08:36 -0400, rickman <gnuarm@gmail.com> wrote:
>
>> Jeff Liebermann wrote on 5/26/2017 1:12 PM:
>>> On Fri, 26 May 2017 12:08:34 -0400, rickman <gnuarm@gmail.com> wrote:
>>>
>>>> Even very hard water won't leave much residue on boards.  At worst it
>>>> would be a very fine powder that should rub off easily.  The photos on
>>>> the web pages Jeff pointed to were from decades of accumulation.
>>>
>>> True.  See my previous rant on the effects of the water heater on lime
>>> concentration.  Cold water doesn't hold very much lime.  Hot water,
>>> run through a water heater that has the bottom of the heater encrusted
>>> with lime deposits, is going to have a much higher lime concentration.
>>> I have a steel tea pot on top of my wood burner.  I boil water in it
>>> when the wood burner is running to keep the humidity high in the
>>> house.  I would guess about 2 liters per day for the last 5 months.
>>> The lid and spout, where there is a temperature drop and the steam
>>> condenses, it encrusted with white rocks.  It's not a huge amount like
>>> in the photos, but spread over a large area, like a pile of PCB's, it
>>> will be quite visible.
>
>> Think about what is wrong with this picture.  Steam is *pure* water.
>> Condensing steam won't add any minerals to the surface.  However, if the
>> pot is actually boiling you get wet steam which has tiny water droplets.
>>  They aren't going to deposit much minerals on a surface even if that
>> surface is cooler because the minerals were able to be dissolved when
>> the water was cool.
>>
>> In this case mineral deposition happens when the water is boiled away
>> leaving the minerals behind.
>>
>> In your water heater the minerals are deposited very little, but over a
>> long time it adds up.
>
> That makes good sense and I would normally agree 100.0%.  However,
> that's not quite what I'm seeing.  Here's the teapot in question:
> <http://802.11junk.com/jeffl/crud/teapot.jpg>
> Unfortunately, I scraped off most of the lime that had built up during
> the winter from the edge of the stainless lid, and around the rusted
> area of the teapot.  It's difficult to see on the white teapot, but
> there was a substantial encrustation.  You can sorta see it in this
> 2010 photo (different teapot but same brand and model):
> <http://802.11junk.com/jeffl/pics/home/slides/wood-burner.html>
> I also scraped off some lime from the inside of the pouring spout, but
> couldn't reach it all.  When I started, the entire inside of the spout
> was encrusted with lime.  Also, notice the lime spot on the top of the
> wood burner.  The bottom of the tea pot has a solid layer of lime over
> the entire surface.
>
> Some of the aforementioned lime deposits came directly from the water,
> with its increased lime concentration would be expected to be
> responsible for the bulk of the lime deposits.  Yet, around the lid
> and inside the spout would be coming from condensed steam.  If it were
> pure dry steam (no saturated liquid water), then I agree.  It's pure
> steam and would contain no lime.  However, at lower temperatures, the
> steam contains quite a bit of water droplets, all loaded with lime.
> That's where the lime around the lid, spout, and wood burner surface
> are coming from.
>
> Incidentally, the label on the teapot says 2.3qts (2.2L).  SLV water
> runs about 300 ppm TDS (total dissolved solids) in 2015:
> <http://www.slvwd.com/ccr/SLVWD-CCR2016-FINAL.pdf>
> ppm is the same as mg/liter, so my 2.2L teapot deposits
>   2.2L * 300mg/L = 660mg
> of lime from each filling.  I refill the teapot an average of twice
> per evening, for 150 days of winter.  Total deposited is:
>   660mg/teapot * 2 fillings * 150 days = 200 grams (about 7 oz).
> That's about 2 of the small salt shakers in this photo:
> <http://802.11junk.com/jeffl/crud/salt.jpg>
> Most of this gets caked onto the bottom of the teapot, but a fairly
> large precentage is sprayed all over the pot and the wood burner.
>
> Note:  I don't drink water from this teapot or use it to make tea.

You didn't say if the water in the pot actually boils or not.  That 
makes a huge difference as boiling puts droplets in the air which 
contain minerals.  The issue of the steam being dry or wet is not really 
the concern.  Steam can start out dry and condense as it cools to become 
wet.  Then it still has no significant minerals.

So if you pot is boiling it is throwing minerals all over the place.  I 
wouldn't be surprised if everything in the room developed a fine mineral 
dust if you boil two pots of water a night.

-- 

Rick C

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Again with flux removal George Herold <gherold@teachspin.com> - 2017-05-25 11:32 -0700
  Re: Again with flux removal John S <Sophi.2@invalid.org> - 2017-05-25 14:37 -0500
  Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-25 15:54 -0400
    Re: Again with flux removal Jon Elson <jmelson@wustl.edu> - 2017-05-25 16:22 -0500
  Re: Again with flux removal Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-05-25 16:20 -0400
    Re: Again with flux removal Sergey Kubushyn <ksi@koi8.net> - 2017-05-25 21:25 +0000
      Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-25 18:31 -0400
        Re: Again with flux removal Sergey Kubushyn <ksi@koi8.net> - 2017-05-26 15:05 +0000
          Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-26 12:06 -0400
        Re: Again with flux removal DemonicTubes <tlackie@gmail.com> - 2017-05-26 10:27 -0700
      Re: Again with flux removal George Herold <gherold@teachspin.com> - 2017-05-26 08:48 -0700
      Re: Again with flux removal Joseph Gwinn <gwinn@comcast.net> - 2017-05-26 18:06 -0400
        Re: Again with flux removal George Herold <gherold@teachspin.com> - 2017-05-26 17:32 -0700
      Re: Again with flux removal Joseph Gwinn <gwinn@comcast.net> - 2017-05-26 18:13 -0400
      Re: Again with flux removal (Test - ignore duplicate) Joseph Gwinn <gwinn@comcast.net> - 2017-05-26 18:20 -0400
      Re: Again with flux removal (Test - ignore duplicate) Joseph Gwinn <gwinn@comcast.net> - 2017-05-26 18:35 -0400
  Re: Again with flux removal Jeff Liebermann <jeffl@cruzio.com> - 2017-05-25 17:15 -0700
    Re: Again with flux removal George Herold <gherold@teachspin.com> - 2017-05-26 06:39 -0700
      Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-26 12:08 -0400
        Re: Again with flux removal Jeff Liebermann <jeffl@cruzio.com> - 2017-05-26 10:12 -0700
          Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-26 14:08 -0400
            Re: Again with flux removal Jeff Liebermann <jeffl@cruzio.com> - 2017-05-26 13:56 -0700
              Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-26 20:35 -0400
                Re: Again with flux removal Jeff Liebermann <jeffl@cruzio.com> - 2017-05-26 18:10 -0700
                Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-26 21:28 -0400
      Re: Again with flux removal Jeff Liebermann <jeffl@cruzio.com> - 2017-05-26 09:45 -0700
        Re: Again with flux removal Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-05-26 10:02 -0700
          Re: Again with flux removal Jeff Liebermann <jeffl@cruzio.com> - 2017-05-26 10:43 -0700
            Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-26 14:00 -0400
  Re: Again with flux removal Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> - 2017-05-25 22:43 -0400
    Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-26 00:43 -0400
      Re: Again with flux removal Sergey Kubushyn <ksi@koi8.net> - 2017-05-26 19:16 +0000
        Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-26 20:46 -0400
          Re: Again with flux removal Sergey Kubushyn <ksi@koi8.net> - 2017-05-27 02:08 +0000
            Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-27 01:06 -0400
              Re: Again with flux removal Sergey Kubushyn <ksi@koi8.net> - 2017-05-27 05:38 +0000
              Re: Again with flux removal Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-27 08:17 +0000
                Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-27 04:37 -0400
                Re: Again with flux removal Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-27 10:33 +0000
                Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-27 11:51 -0400
                Re: Again with flux removal Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-27 15:59 +0000
                Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-27 12:13 -0400
                Re: Again with flux removal Jan Panteltje <pNa0nStpealmtje@yahoo.com> - 2017-05-27 16:27 +0000
    Re: Again with flux removal George Herold <gherold@teachspin.com> - 2017-05-26 07:00 -0700
      Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-26 12:13 -0400
  Re: Again with flux removal whit3rd <whit3rd@gmail.com> - 2017-05-25 21:28 -0700
    Re: Again with flux removal George Herold <gherold@teachspin.com> - 2017-05-26 07:04 -0700
      Re: Again with flux removal rickman <gnuarm@gmail.com> - 2017-05-26 12:16 -0400
      Re: Again with flux removal whit3rd <whit3rd@gmail.com> - 2017-05-26 14:33 -0700

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