I want to build a degreasing tank using Caustic Soda (aka Sodium Hydroxide or
Lye) as the active agent. I am already aware of the necessary safety
precautions and EPA considerations. My questions a what material for the
tank and how strong a solution? Thanks.

Roger in Vegas

Roger Hull wrote:

I want to build a degreasing tank using Caustic Soda (aka Sodium Hydroxide or
Lye) as the active agent. I am already aware of the necessary safety
precautions and EPA considerations. My questions a what material for the
tank and how strong a solution? Thanks.


I suggest using an old drum. If it's too tall, cut it off. Easy to make a
sheet metal lid for. Here's the deal, though. Try to get one that has no
paint and no rust on it. Sometimes drum companies strip their drums and
repaint them, and if they do, you can buy them stripped.

One pound lye per 3-5 gallons of water is a pretty strong solution.

Any lye solution will be more aggressive heated. Advantage of a metal tank
is you can put it on an outdoor propane turkey-fryer-type burner directly.

GWE

In article t,
Roger Hull wrote:

I want to build a degreasing tank using Caustic Soda (aka Sodium Hydroxide or
Lye) as the active agent. I am already aware of the necessary safety
precautions and EPA considerations. My questions a what material for the
tank and how strong a solution? Thanks.

Roger in Vegas


NOT aluminum. Or Magnesium or Titanium. If I rememebr my high school
chemistry correctly (and I admit, it's been quite a few years...) all
three will die tragic deaths soon after contact with a strong lye
solution. As for "how strong?", well... That's almost certainly going to
depend on the "grunge" level of each piece you want to tank - Nastier
pieces will probably need a stronger solution, "light crud"/finish
cleaning probably won't need anywhere near the strength.

--
Don Bruder - - New Email policy in effect as of Feb. 21, 2004.
Short form: I'm trashing EVERY E-mail that doesn't contain a password in the
subject unless it comes from a "whitelisted" (pre-approved by me) address.
See http://www.sonic.net/~dakidd/main/contact.html for full details.

"Roger Hull" skrev i en meddelelse
s.net...
I want to build a degreasing tank using Caustic Soda (aka Sodium Hydroxide
or
Lye) as the active agent. I am already aware of the necessary safety
precautions and EPA considerations. My questions a what material for
the
tank and how strong a solution? Thanks.


Regular or stainless steel should be fine..
I'd suggest a 2% solution.. Not strong enough to do any serious damage to
your skin on short term exposure, but strong enough to remove the worst
parts..

If you want it more effective you could heat the solution to 60-70 C..

/peter

Roger Hull writes:

My questions a what material for the
tank and how strong a solution?

Cheap version is a Rubbermaid Brute trash can, if you watch the heat.

"Q" wrote in message
k...

"Roger Hull" skrev i en meddelelse
s.net...
I want to build a degreasing tank using Caustic Soda (aka Sodium
Hydroxide
or
Lye) as the active agent. I am already aware of the necessary safety
precautions and EPA considerations. My questions a what material for
the
tank and how strong a solution? Thanks.


Regular or stainless steel should be fine..
I'd suggest a 2% solution.. Not strong enough to do any serious damage to
your skin on short term exposure, but strong enough to remove the worst
parts..

If you want it more effective you could heat the solution to 60-70 C..

/peter


If you use it hot be careful of stainless as some sodium hydroxide contains
chloride.

"David Deuchar" skrev i en meddelelse
news
If you want it more effective you could heat the solution to 60-70 C..

/peter


If you use it hot be careful of stainless as some sodium hydroxide
contains
chloride.

I work for a rather large dairy company.. The preferred cleaning process
for tanks, pipes etc. is a short rinse with water followed by 2% sodium
hydroxide @ 80C, short rinse w. water, 1% nitric acid @ 60C followed by a
rinse with fresh water.. The cleaning fluids are recycled and stored in
large stainless steel tanks ( 316L )..

Some of the tanks cleaned with this system are used to store brine for the
cheese ( 20% sodium chloride ), so contamination of the cleaning fluids is a
frequent issue ( The returnline for the cleaning fluid is routed between lye
and acid tanks and the sewer, but the conductivity sensor cant tell the
difference )..

The stainless steel tends to turn brittle and nearly impossible to weld
cracks on, but we have only seen this happen on really old equipment..

/peter

If you use it hot be careful of stainless as some sodium hydroxide contains
chloride.


Is there an issue with stainless and chlorides? - GWE

"Roger Hull" wrote in message
s.net...
I want to build a degreasing tank using Caustic Soda (aka Sodium Hydroxide
or
Lye) as the active agent. I am already aware of the necessary safety
precautions and EPA considerations. My questions a what material for
the
tank and how strong a solution? Thanks.

Roger in Vegas


I worked as an engineer in the food industry for more years than I care to
remember. We traditionally used mild steel tanks for the storage of our
caustic cleaning solutions and never had corrosion problems. The usual
strength of the solution was about 2-3%. Back when beer bottles were washed
and reused. the bottle washers were mild steel and had caustic solutions of
up to 7% and 75 Degrees C.for quick removal of labels. Again, corrosion was
never a problem.

Tom

On Tue, 8 Mar 2005 7:27:32 -0800, Roger Hull
wrote:

I want to build a degreasing tank using Caustic Soda (aka Sodium Hydroxide or
Lye) as the active agent. I am already aware of the necessary safety
precautions and EPA considerations. My questions a what material for the
tank and how strong a solution? Thanks.

Roger in Vegas

I don't know if I can find another racing fuel barrel , plastic out?
If its SS its mine. So, do you want me to find ya another? I've seen
plastic ones for IIRC $5-$10 in the paper. Let me know, I can spot the
metal ones a mile away if I need one.

On Tue, 8 Mar 2005 15:38:10 -0800, Sunworshipper wrote
(in message ):

On Tue, 8 Mar 2005 7:27:32 -0800, Roger Hull
wrote:

I want to build a degreasing tank using Caustic Soda (aka Sodium Hydroxide
or
Lye) as the active agent. I am already aware of the necessary safety
precautions and EPA considerations. My questions a what material for
the
tank and how strong a solution? Thanks.

Roger in Vegas

I don't know if I can find another racing fuel barrel , plastic out?
If its SS its mine. So, do you want me to find ya another? I've seen
plastic ones for IIRC $5-$10 in the paper. Let me know, I can spot the
metal ones a mile away if I need one.

If you can come up with another metal drum that would be super. Thanks.

On Tue, 8 Mar 2005 17:14:19 -0800, Roger Hull
wrote:

On Tue, 8 Mar 2005 15:38:10 -0800, Sunworshipper wrote
(in message ):

On Tue, 8 Mar 2005 7:27:32 -0800, Roger Hull
wrote:

I want to build a degreasing tank using Caustic Soda (aka Sodium Hydroxide
or
Lye) as the active agent. I am already aware of the necessary safety
precautions and EPA considerations. My questions a what material for
the
tank and how strong a solution? Thanks.

Roger in Vegas

I don't know if I can find another racing fuel barrel , plastic out?
If its SS its mine. So, do you want me to find ya another? I've seen
plastic ones for IIRC $5-$10 in the paper. Let me know, I can spot the
metal ones a mile away if I need one.

If you can come up with another metal drum that would be super. Thanks.

In the works. You know I saw one just last week, where the hell was
that???

"David Deuchar" wrote in message
news
If you use it hot be careful of stainless as some sodium hydroxide
contains
chloride.

Chemical question, shouldn't the protective chromium oxide on stainless be
attacked by lye to form sodium chromate? Why not?

Tim

--
"California is the breakfast state: fruits, nuts and flakes."
Website: http://webpages.charter.net/dawill/tmoranwms

On Tue, 08 Mar 2005 18:46:52 -0800, Sunworshipper
wrote:

On Tue, 8 Mar 2005 17:14:19 -0800, Roger Hull
wrote:

On Tue, 8 Mar 2005 15:38:10 -0800, Sunworshipper wrote
(in message ):

On Tue, 8 Mar 2005 7:27:32 -0800, Roger Hull
wrote:

I want to build a degreasing tank using Caustic Soda (aka Sodium Hydroxide
or
Lye) as the active agent. I am already aware of the necessary safety
precautions and EPA considerations. My questions a what material for
the
tank and how strong a solution? Thanks.

Roger in Vegas

I don't know if I can find another racing fuel barrel , plastic out?
If its SS its mine. So, do you want me to find ya another? I've seen
plastic ones for IIRC $5-$10 in the paper. Let me know, I can spot the
metal ones a mile away if I need one.

If you can come up with another metal drum that would be super. Thanks.

In the works. You know I saw one just last week, where the hell was
that???


LOL , ahhh Reefer ok? Got to pick it up between 7-9 am tomorrow !

Fast eh? ) Color not optional.

What 20 hours.

"Grant Erwin" wrote in message
...

If you use it hot be careful of stainless as some sodium hydroxide
contains chloride.

Is there an issue with stainless and chlorides? - GWE

Chloride SCC

David Deuchar wrote:

"Grant Erwin" wrote in message
...

If you use it hot be careful of stainless as some sodium hydroxide
contains chloride.

Is there an issue with stainless and chlorides? - GWE


Chloride SCC

Long on words, aren't you, David? OK, let's try again! What do you mean
by "Chloride SCC"? Thanks - GWE

Roger Hull wrote:

I want to build a degreasing tank using Caustic Soda (aka Sodium Hydroxide or
Lye) as the active agent. I am already aware of the necessary safety
precautions and EPA considerations. My questions a what material for the
tank and how strong a solution? Thanks.

Roger in Vegas



old style potato peelers and peach peelers in the food industry used
strong lye solutions in carbon steel tanks. The lye tends to protect
the metal and I've never seen one actually rust or corrode out. The
carbon steel metal conveyor belting we ut in them lasted for years.

Don't paint it though....for some reason people liked to paint these
tanks (outside) during shut-down cycles while they were painting the
rest of the equipment that needed it. Paint lasts about a minute.


Koz

"Grant Erwin" wrote in message
...
David Deuchar wrote:

"Grant Erwin" wrote in message
...

If you use it hot be careful of stainless as some sodium hydroxide
contains chloride.

Is there an issue with stainless and chlorides? - GWE


Chloride SCC

Long on words, aren't you, David? OK, let's try again! What do you mean
by "Chloride SCC"? Thanks - GWE

Probably the most researched corrosion issue in the world.
Simple slightly inaccurate explanation. Take an austenitic stainless steel,
(the type that is non magnetic), add stress eg welding or cold work, put in
hot salty water. Result:- cracks in the steel. The steel will look OK unless
you have a hand lens to look for the cracks but it will leak. To avoid:- use
duplex stainless steel.

http://www.hghouston.com/cl_scc.html

http://www.mcnallyinstitute.com/CDweb/c-html/c036.htm

http://www.safeclimbing.org/education/deepbluesea.htm

http://www.firth-metals.com/english/...ng07-06-04.pdf

http://www.npl.co.uk/ncs/docs/stress.pdf

http://www.corrosionsource.com/techn.../pdf/14050.pdf

The classic case is the Swiss swimming pool roof collapse, mainly used
because it is a long time ago, there are tens of thousands of more recent
cases.
Stress corrosion cracking
A material failure may be accelerated by the combined effect of corrosion
and mechanical stress. The most common type is transgranular
stress-corrosion cracking, SCC, that may develop in concentrated
chloride-containing environments. Previously, it was generally considered
that an elevated temperature was necessary for SCC to occur. In recent
years, however, SCC has been experienced at ambient temperature on standard
grade steels like 304(L) or 316(L) that were exposed to high tensile
stresses. In these cases the steel surface was contaminated with solid salt
deposits and the humidity of the atmosphere was rather high. These two
factors resulted in a thin liquid film saturated with chloride. Other
contaminants, such as H2S, may increase the risk of SCC in chloride
containing environments. Other environments that may give rise to SCC,
particularly on low alloy steels, include very alkaline solutions at high
temperatures. A typically SCC attack takes the form of thin, branched
cracks.



Stress Corrosion Cracking (SCC)
Under the combined effects of stress and certain corrosive environments
stainless steels can be subject to this very rapid and severe form of
corrosion. The stresses must be tensile and can result from loads applied in
service, or stresses set up by the type of assembly e.g. interference fits
of pins in holes, or from residual stresses resulting from the method of
fabrication such as cold working. The most damaging environment is a
solution of chlorides in water such as sea water, particularly at elevated
temperatures. As a consequence stainless steels are limited in their
application for holding hot waters (above about 50°C) containing even trace
amounts of chlorides (more than a few parts per million). This form of
corrosion is only applicable to the austenitic group of steels and is
related to the nickel content. Grade 316 is not significantly more resistant
to SCC than is 304. The duplex stainless steels are much more resistant to
SCC than are the austenitic grades, with grade 2205 being virtually immune
at temperatures up to about 150°C, and the super duplex grades are more
resistant again. The ferritic grades do not generally suffer from this
problem at all.

In some instances it has been found possible to improve resistance to SCC by
applying a compressive stress to the component at risk; this can be done by
shot peening the surface for instance. Another alternative is to ensure the
product is free of tensile stresses by annealing as a final operation. These
solutions to the problem have been successful in some cases, but need to be
very carefully evaluated, as it may be very difficult to guarantee the
absence of residual or applied tensile stresses.

From a practical standpoint, Grade 304 may be adequate under certain
conditions. For instance, Grade 304 is being used in water containing 100 -
300 parts per million (ppm) chlorides at moderate temperatures. Trying to
establish limits can be risky because wet/dry conditions can concentrate
chlorides and increase the probability of stress corrosion cracking. The
chloride content of seawater is about 2% (20,000 ppm). Seawater above 50°C
is encountered in applications such as heat exchangers for coastal power
stations.

Recently there have been a small number of instances of chloride stress
corrosion failures at lower temperatures than previously thought possible.
These have occurred in the warm, moist atmosphere above indoor chlorinated
swimming pools where stainless steel (generally Grade 316) fixtures are
often used to suspend items such as ventilation ducting. Temperatures as low
as 30 to 40°C have been involved. There have also been failures due to
stress corrosion at higher temperatures with chloride levels as low as 10
ppm. This very serious problem is not yet fully understood.

On Thu, 10 Mar 2005 11:57:15 -0800, David Deuchar wrote
(in message ):
Major snip


Stress Corrosion Cracking (SCC)
Under the combined effects of stress and certain corrosive environments
stainless steels can be subject to this very rapid and severe form of
corrosion. The stresses must be tensile and can result from loads applied in
service, or stresses set up by the type of assembly e.g. interference fits
of pins in holes, or from residual stresses resulting from the method of
fabrication such as cold working. The most damaging environment is a
solution of chlorides in water such as sea water, particularly at elevated
temperatures.

major snip

"Caustic Embrittlement" is/was a common term to steam boiler operators back
when I was one; slightly over ten years ago. We used Caustic Soda to treat
the boiler water for Ph, along with a bunch of other chemicals to remove
dissolved Oxygen, Carbon Dioxide, minerals, control foaming, ect. You cannot
feed boilers tap water (for long).

"Roger Hull" wrote in message
s.net...
On Thu, 10 Mar 2005 11:57:15 -0800, David Deuchar wrote
(in message ):
Major snip


Stress Corrosion Cracking (SCC)
Under the combined effects of stress and certain corrosive environments
stainless steels can be subject to this very rapid and severe form of
corrosion. The stresses must be tensile and can result from loads applied
in
service, or stresses set up by the type of assembly e.g. interference
fits
of pins in holes, or from residual stresses resulting from the method of
fabrication such as cold working. The most damaging environment is a
solution of chlorides in water such as sea water, particularly at
elevated
temperatures.

major snip

"Caustic Embrittlement" is/was a common term to steam boiler operators
back
when I was one; slightly over ten years ago. We used Caustic Soda to treat
the boiler water for Ph, along with a bunch of other chemicals to remove
dissolved Oxygen, Carbon Dioxide, minerals, control foaming, ect. You
cannot
feed boilers tap water (for long).

Yes but it should not be a problem for caustic cleaning solutions as it
tends to occur at higher temperatures.

"Low concentrations of caustic can be safely handled by carbon steel up to
180oF/82oC, where CSCC starts to become a risk factor, while the safe upper
limit for a 50% solution is approximately 150oF/65oC"

"Austenitic Stainless SteelsAustenitic (300 series) stainless steels possess
good resistance to caustic up to approximately 50% and temperatures about
200oF/93oC. At, and above 200oF/93oC, the austenitics exhibit unstable
passivity and can suffer severe general corrosion if activated. Above
approximately 250oF/121oC they are susceptible to SCC (see Figure). No
distinction is made between 304SS and 316SS regarding resistance to caustic
as their behaviors are similar. They are also susceptible to chloride SCC if
substantial chlorides are present in low grade caustic. "

http://www.hghouston.com/naoh.html

On Thu, 10 Mar 2005 22:51:44 GMT, "David Deuchar"
wrote:


"Roger Hull" wrote in message
us.net...
On Thu, 10 Mar 2005 11:57:15 -0800, David Deuchar wrote
(in message ):
Major snip


Stress Corrosion Cracking (SCC)
Under the combined effects of stress and certain corrosive environments
stainless steels can be subject to this very rapid and severe form of
corrosion. The stresses must be tensile and can result from loads applied
in
service, or stresses set up by the type of assembly e.g. interference
fits
of pins in holes, or from residual stresses resulting from the method of
fabrication such as cold working. The most damaging environment is a
solution of chlorides in water such as sea water, particularly at
elevated
temperatures.

major snip

"Caustic Embrittlement" is/was a common term to steam boiler operators
back
when I was one; slightly over ten years ago. We used Caustic Soda to treat
the boiler water for Ph, along with a bunch of other chemicals to remove
dissolved Oxygen, Carbon Dioxide, minerals, control foaming, ect. You
cannot
feed boilers tap water (for long).

Yes but it should not be a problem for caustic cleaning solutions as it
tends to occur at higher temperatures.

"Low concentrations of caustic can be safely handled by carbon steel up to
180oF/82oC, where CSCC starts to become a risk factor, while the safe upper
limit for a 50% solution is approximately 150oF/65oC"

"Austenitic Stainless SteelsAustenitic (300 series) stainless steels possess
good resistance to caustic up to approximately 50% and temperatures about
200oF/93oC. At, and above 200oF/93oC, the austenitics exhibit unstable
passivity and can suffer severe general corrosion if activated. Above
approximately 250oF/121oC they are susceptible to SCC (see Figure). No
distinction is made between 304SS and 316SS regarding resistance to caustic
as their behaviors are similar. They are also susceptible to chloride SCC if
substantial chlorides are present in low grade caustic. "

http://www.hghouston.com/naoh.html


Well, I dropped off a re-ferb drum to him , I'm sure I'll hear from
the stub legged user someday if it fails. SS drum, got to find one of
those, I would never set it out on the curb. Never saw one.

I could care less what ole Roger want's with it. All I know is that I
had to make a special stop just to take the big plug out (facing down)
so some candy ass didn't drop a dime on it.

SW, who would have loved chemistry , but was excluded for obvious
reasons. I bet if I said boo in yuppy park 10 women would jump over
their kids. How much for the wife and kids??? LOL, I'd love to show
them a picture of my kid and how all theirs' don't add up to near
cuteness !!!

Life is fun. See the sheep people run.

Sunworshipper: Thanks again for the drum. I will see it gets put to good
use.
Roger in Vegas
Worlds Greatest Impulse Buyer