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Disposing of caustic soda?

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Donnie

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Aug 26, 2010, 11:20:36 AM8/26/10
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Hey all, just filled a tub in the back yard with a caustic soda mix to
clean up an old 2 stroke exhaust but it's just occurred to me that
there will be approximately 3 or 4 gallons of caustic soda / rust mix
to dispose of.

I am assuming I can dump it down the outside drain as caustic soda can
actually be used to clean drains?
--
Donnie

Clot

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Aug 26, 2010, 12:26:45 PM8/26/10
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Is the outside drain connected to a surface water sewer that goes to a local
stream? The aquatic wildlife might not like that! If it connects to a foul
sewer - OK.

Are you connected to a local foul sewer that goes to a sewage works? If so,
then down the kitchen sink or a bog would be the best bet.


Dave H.

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Aug 26, 2010, 12:31:35 PM8/26/10
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"Donnie" <NOTV...@hotmail.com> wrote in message
news:i560o4$mb8$1...@news.eternal-september.org...

Yep, sure can - be aware that any fat in the drain will turn to soap though,
and swells about 50% in the process, so running some *hot* water through
before and after could be a good idea if your drain's already a bit clogged?

On the subject of soda and cleaning steel, have you heard of the Bubbling
Electric Gunge Tank method for removing rust? Big plastic tub, battery
charger, half a cup of *washing* soda to each bucket of water, then connect
the +ve from the charger to a piece of scrap iron, -ve to the piece to
clean, leave for a few days - saves all that tiresome messing about with
wire brushes, strong acids etc., and often does a good job of stripping
paint too! (Google "electrolytic rust removal" for more details) The
leftover liquid's drain-safe as long as you don't use stainless for the +ve
electrode (which will eventually dissolve into the solution), stainless will
make lots of hexavalent chromium in the solution, which is Very Bad Stuff.

Dave H.
--
(The engineer formerly known as Homeless)

"Rules are for the obedience of fools, and the guidance of wise men" -
Douglas Bader


Spamlet

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Aug 26, 2010, 1:22:12 PM8/26/10
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"Donnie" <NOTV...@hotmail.com> wrote in message
news:i560o4$mb8$1...@news.eternal-september.org...

Depends what you mean by the outside drain. The ones in the street usually
go straight into a watercourse, though some on busy roads go into big soak
always to clean up the water a bit first. Car cleaning in the street can be
bad news for local river life, and garages with car washes, were, on a
survey I once did, the most common source of local river pollution - the
next being people plumbing in foul waste to the surface water pipes by
'mistake'.

So best to check first and see where the waste goes when you flush the loo -
or pour a bucket at a time down the loo.

The solution in your tub will gradually turn to sodium carbonate solution
from contact with the air's CO2: this is 'washing soda', so what you would
be doing by pouring it down the foul sewer would not be greatly different to
doing a lot of washing. For other chemicals - like the chromium salts
mentioned in another reply - pouring down *any* drain is generally a no no.

S


Donnie

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Aug 26, 2010, 2:47:15 PM8/26/10
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Clot wrote:

Ohhh that hadnt crossed my mind, I guess the bog will be the best
really then

--
Donnie

Donnie

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Aug 26, 2010, 2:50:20 PM8/26/10
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Dave H. wrote:

>
> "Donnie"

<<SNIP>>


>
> Yep, sure can - be aware that any fat in the drain will turn to soap

> though, and swells about 50% in the process, so running some hot


> water through before and after could be a good idea if your drain's
> already a bit clogged?

It's not but I guess it never does any harm to pre flush the pipe just
in case


>
> On the subject of soda and cleaning steel, have you heard of the
> Bubbling Electric Gunge Tank method for removing rust? Big plastic

> tub, battery charger, half a cup of washing soda to each bucket of


> water, then connect the +ve from the charger to a piece of scrap
> iron, -ve to the piece to clean, leave for a few days - saves all
> that tiresome messing about with wire brushes, strong acids etc., and
> often does a good job of stripping paint too! (Google "electrolytic
> rust removal" for more details) The leftover liquid's drain-safe as
> long as you don't use stainless for the +ve electrode (which will
> eventually dissolve into the solution), stainless will make lots of
> hexavalent chromium in the solution, which is Very Bad Stuff.

I'd heard something like this before I must admit but never did give it
a try, could be interesting to experiment with it.

--
Donnie

Donnie

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Aug 26, 2010, 2:52:21 PM8/26/10
to
Spamlet wrote:

>
> "Donnie" <SNIP>


>
> So best to check first and see where the waste goes when you flush
> the loo - or pour a bucket at a time down the loo.

I know my loo pipe goes to sewage already so this will be the best
route of disposal i guess.

--
Donnie
Honda CB500R "Look out, Donnie's about!"
Lambretta Series 2 186cc "The Shitter"
Lambretta LD 175cc "The Chopper"

The Natural Philosopher

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Aug 26, 2010, 2:53:40 PM8/26/10
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yes. Or mix oil with it to form the sort of detergent the drains cope
with every day.

With enough water in it, its not that evil a mix.


Spamlet

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Aug 26, 2010, 3:56:15 PM8/26/10
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"The Natural Philosopher" <t...@invalid.invalid> wrote in message
news:i56d7k$u7r$2...@news.albasani.net...

You actually have to boil vegetable oil or animal fats with caustic for some
time for specification. and it is not possible for mineral oils or paraffin
waxes:

http://en.wikipedia.org/wiki/Saponification
http://en.wikipedia.org/wiki/Unsaponifiable

In testing oils, one key test of purity is its 'sap value'.

When oils are emulsified they are actually more polluting than when they are
separated out from the water environment: the difference would be like you
walking through a puddle of oil as opposed to having it sprayed at you in a
mist that you could not avoid breathing in.

S


Tabby

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Aug 26, 2010, 5:26:44 PM8/26/10
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Couldnt you freecycle it as caustic drain cleaner?


NT

Donnie

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Aug 26, 2010, 6:44:40 PM8/26/10
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Tabby wrote:

heh

--
Donnie

Spamlet

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Aug 26, 2010, 7:36:51 PM8/26/10
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"Spamlet" <spam.m...@invalid.invalid> wrote in message
news:i56gt9$cdb$1...@news.eternal-september.org...

>
> "The Natural Philosopher" <t...@invalid.invalid> wrote in message
> news:i56d7k$u7r$2...@news.albasani.net...
>> Donnie wrote:
>>> Hey all, just filled a tub in the back yard with a caustic soda mix to
>>> clean up an old 2 stroke exhaust but it's just occurred to me that
>>> there will be approximately 3 or 4 gallons of caustic soda / rust mix
>>> to dispose of.
>>>
>>> I am assuming I can dump it down the outside drain as caustic soda can
>>> actually be used to clean drains?
>> yes. Or mix oil with it to form the sort of detergent the drains cope
>> with every day.
>>
>> With enough water in it, its not that evil a mix.
>>
>>
>
> You actually have to boil vegetable oil or animal fats with caustic for
> some time for specification. and it is not possible for mineral oils or
> paraffin waxes:

Grr just noticed what the spell checker has done! Saponification not
'specification' stupid dumb dictionary!

stuart noble

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Aug 27, 2010, 4:34:11 AM8/27/10
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On 26/08/2010 20:56, Spamlet wrote:
> "The Natural Philosopher"<t...@invalid.invalid> wrote in message
> news:i56d7k$u7r$2...@news.albasani.net...
>> Donnie wrote:
>>> Hey all, just filled a tub in the back yard with a caustic soda mix to
>>> clean up an old 2 stroke exhaust but it's just occurred to me that
>>> there will be approximately 3 or 4 gallons of caustic soda / rust mix
>>> to dispose of.
>>>
>>> I am assuming I can dump it down the outside drain as caustic soda can
>>> actually be used to clean drains?
>> yes. Or mix oil with it to form the sort of detergent the drains cope with
>> every day.
>>
>> With enough water in it, its not that evil a mix.
>>
>>
>
> You actually have to boil vegetable oil or animal fats with caustic for some
> time for specification. and it is not possible for mineral oils or paraffin
> waxes:
>

Vegetable oils can be saponified (or personified, magnified, stratified,
if your spell checker prefers :-)) at room temperature. Solids, such as
wax, need to be heated, but only to their melting point.
Beeswax e.g. can be emulsified (i.e. made virtually soluble in water) at
70 degsC with the mere hint of alkali, or completely saponified (and
turned back into a solid) by adding more. Somewhere in between should be
a water based wax polish.

chris French

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Aug 27, 2010, 8:24:13 PM8/27/10
to
In message <i56d54$do1$1...@news.eternal-september.org>, Donnie
<NOTV...@hotmail.com> writes

>Spamlet wrote:
>
>>
>> "Donnie" <SNIP>
>>
>> So best to check first and see where the waste goes when you flush
>> the loo - or pour a bucket at a time down the loo.
>
>I know my loo pipe goes to sewage already so this will be the best
>route of disposal i guess.
>
If it is an older house (pre ww2? it probably depends a lot, but it
applied to our 1930's semi in Leeds) then you may well fin the foul
water sewer and the rain water drain combined.

It's easy enough to check - open a manhole and watch to see if both
foul water and rain water go down the same drain.
--
Chris French

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