Peroxide for Algae Control?

[sjohns4]

I'm working with a cash-strapped client to bring their treatment lagoons back into compliance. Part of the problem, due to the reduction in flow from the facility, is the long HRT in the lagoons. The first pond is aerated, so I'm hoping we can come up with a small blower & diffuser arrangement to keep the DO high enough to minimize algae growth. However, I'm concerned about the two polishing ponds after the aerated pond. I was reading into case studies where barley straw has successfully been used to control algae, but it's due to the release of hydrogen peroxide. Barley straw is hard to come by here, but peroxide isn’t. The paper recommended a dose of 2 ppm of peroxide. My question is, IF we dosed the peroxide at the influent to the aerated pond, would it inhibit the desired biological activity. I'm hoping to dose after the aerated pond, but if we do see algae problems in the aerated pond could we move the dose point to the pond influent?

Thoughts?

Thanks,

Mike

 

[bimr]

If you are concerned about costs, then peroxide is not the way to go. While it will work, peroxide will break the budget.

In the long run, a workable design will meet the treatment objective at the lowest cost.

 

[sjohns4]

Not for a 3000 GPD system. We'd be spending about $150 per year from the local supplier.

 

[bimr]

If you have a long detention time in the pond, it is most likely that you will have to dose the entire pond in order to prevent algae.

Adding 2 mg/l to the influent is probably unlikely to kill algae in the pond. The peroxide will be gone in several hours. H2O2 is highly reactive with organics and dissipates quickly.

People with fish ponds add much higher doses of peroxide every 2 weeks to keep the algae out. H2O2 also doesn't work as well after the algae are already present.

Have the supplier do a demonstration and let everyone know how it works.

 

[DrLewinstein]

Your question is six weeks old so you may have already addressed the problem, but Dr. Gene Rich in his book "High Performance Aerated Lagoons" shows that an HRT <2 days will keep algae washed out. Can you put curtains or something in the lagoon so that it will keep washed out?

 

[sjohns4]

We were able to get ahold of some barley straw. They also have a fairly new existing blower which is very much oversized. Our plan is to install some low-cost coarse bubble caps throughout the aerated lagoon portion and use the barley straw in the non-aerated polishing / settling ponds. The diffuser caps are spaced to provide good mixing throughout the pond, which combined with the more than adequate air to keep O2 levels up, should curb the algale in the first pond.
They have already placed the barley in the polishing bonds but are a bit behind on the aeratior installation. No algae in the polishing ponds but the growth has started in the aerated pond. Barley straw seems to be working!

 

[DrLewinstein]

I had never heard of the barley straw use for algae control. Here is an interesting article on it by Purdue.

http://www.btny.purdue.edu/pubs/apm/apm-1-w.pdf