Algae problem at my workplace..but not in a swimming pool!!

I work in an aluminum extrusion plant and we have an anodizing line, which is a chemical/water based line that etches, colors then seals the aluminum extrusion and is used mainly in architectual applications such as window/door systems in high rise buildings, schools, mini malls and pretty much anything non-residential.

We have been looking for ways to increase production through this line and our chemical vendor has supplied us with an additive to decrease the time a work rail spends in the anodizing tank which is filled with water and sulfuric acid. Our tanks our 8 feet deep and 40 feet long.

The additive works very well, but is extremely expensive so we quit using it for awhile, but once again due to production requirements we started using it again.

Every time we use this additive (I'm actually not sure what it is) our rinse tanks, which some use city water, and one uses DI water grows algae pretty bad and pretty quickly. Our chemical vendor has supplied us with a thing they call a "bug zapper." It's apparently an electrical probe that emits electricity to the tank in effect "zapping" the algae. We are trying them out and they seem to be working okay, but at the tune of $7000 each they aren't cheap.

I asked if we could use chlorine to fight the algae in these tanks, but found out the chlorine would have a negative effect on our seal and color tanks so that is not an option.

Has anyone heard of these "bug zappers" and do they make something like this for a swimming pools?

I found out some information on our new "bug zapper." It is called a "zeta rod" and can be seen at www.zetacorp.com. The web site explains how the rod works and what purpose it serves, but it is a little deep for me. It almost sounds like the magnet thing that miraculously takes care of everything, but if these are being used in waste water treatment there may be some merit to them. I believe someone on this board is in the water treatment industry (I guess we all are with our pools :D ) may know more about this. I hope some of you chemists and engineers chime in and let me know what you think. I will keep an eye on ours and see how effective it is and if it is worth $7000.

The website has more than a few red flags !

A couple examples:

1. Colloids in water systems become components of the capacitor receive a strong boost to their natural surface charge, altering double-layer conditions that govern particle interactions.

Colloid as defined by Websters -
a : a substance that consists of particles dispersed throughout another substance which are too small for resolution with an ordinary light microscope but are incapable of passing through a semipermeable membrane.
b : a mixture consisting of a colloid together with the medium in which it is dispersed <smoke is a colloid>

Well that seems to indicate that tiny unseen particles become part of the Capacitor. Where said capacitor is however, I can't fathom !!

2. Through innovative design, space-age materials were combined with down-to-earth engineering know-how to create the Zeta Rod™, a vitrified ceramic (similar to the material used in the tiles that provide heat shielding for the space shuttle) electrode capable of holding an extremely high voltage electrostatic charge

You have to question the use of a phrase like "down-to-earth engineering know-how". And I always get skeptical when they refer to similarities to items used by NASA.

Even if this worked (maybe it's electrocuting the algae?). I can't see how it could do so effectively in a moving stream of liquid.

Maybe someone with an engineering degree can decipher the explanation on the website and tell us what the science is and if it could work.

Just an update:
I have been watching these things for the last few weeks to see how effective they are. I have to say they are working...somewhat. We have 2 of them on our rinse tanks and they are probably 85% to 90% effective. They are not getting all of the algae, but enough of it to where we aren't constantly dumping the water and refilling. So they are effective enough for us to get production through without having these tanks cause problems with the aluminum extrusions.

Thank you haze on your input. I would also love to hear from waterbear or chemgeek to see what y'all think.

JD

Well, we know that Borates (Boric Acid or Sodium Tetraborate / Borax) at a level of 50 ppm (Boron) will inhibit algae growth so that seems like one possibility. I can't guarantee that the Boric Acid won't cause harm, but it certainly won't be an oxidant like chlorine. I also assume you would adjust your water pH to be around 7 or wherever you want it, but slightly alkaline to avoid metal corrosion.

If you are getting lots of algae growth, then whatever it is you are rinsing (such as the additive) must also be providing nitrates, phosphates and sulfur (sulfates) because all three are needed (plus some light) for algae to grow. Clearly the sulfuric acid provides sulfates so perhaps the chemical additive is providing nitrates and phosphates. You probably can't do anything about what you are rinsing, but you can control light in the tank. Perhaps keeping the tanks dark plus the use of Borates will be all that is needed for this algae problem.

Anyway, that's my two cents -- for what it's worth.

Oh yes, as for the zeta rod, it makes sense though they make it sound so much more mysterious than it actually is. Essentially the basic principle is simply to put strong charges on anything suspended in the water, and that would include algae, and this prevents them from clumping together or sticking to the sides of the tank since like charges repel each other. It doesn't seem to kill what is in the water, but prevents it from forming colonies -- perhaps such lonely algae and bacteria don't replicate as well all by themselves (just kidding, but not having them settle, clump or attach would mean that any such growth would be minimal with decent flow rates).

Richard

Hello All,
I thought I would post an update on our zeta rods we are using at work. I kinda forgot about them until the other day (I actually don't work in that department, my boss is over it though.) I went over and took a look at them and they are looking a little worse for the wear. We have 2 installed and it looks like 1 of them is broken because the power supply is unhooked to it which leaves us with the 1. I asked my boss how they were doing and he commented they just half*** work. He said they do help some, but they are not the "miracle cure" that the website seems to evoke. The additive we use in our anodizing tanks have some sort of "sugars" in them and algae seems to thrive off of it. So we are constantly having to decant that tank to keep algae at bay. I guess that's the cost of more production;) .