Does PC power supply work?

[acidrain]

I'm sure the acid will react differently than water, but basically you have it right.
I use a 1500watt chiller... when I'm running a large batch of 25 or 30 amps at 15 volts, it can't keep up with the temp rise.

[Grumple]

So small batches and longer anodize times you can get away without a chiller I guess. I seen a pic where someone used a small a/c unit in an enclosure for a chiller. Not a bad idea. Is your chiller a commercial unit or did you make it?

[acidrain]

It's a commercial salt water fish tank chiller with titanium core.
HVAC uses a window mount AC unit blowing cold air into the box that hold his tank, and I guess it works quite well.

[HarryP]

The effect of acid on cooling requirements goes like this: the acid raises to density. So a gallon of anodiser will weigh more than a gallon of water. A 10% by volume bath will a specific gravity of about 1.1. However the specific heat will reduce by a similar amount. So the the energy required to raise/lower the temperature will be the same as for an equal volume of water.

In addition to the heating from the electrical energy, chemical energy is produced by the conversion of aluminium to it's oxide. This generally amounts to about 10% of the electrical energy.

Most of the energy, electrical and chemical, is dissipated in the anodic film. To get good quality anodizing it is necessary to use agitation to remove the heat from the surface. Otherwise you may get a coating produced at an apparent 68 degrees have the properties of a film produced at 80 degrees or more (which it has been).

[Grumple]

HarryP,
Thanks for the follow-up explanation. I now know that agitation is an important process, more than I initially thought.