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How AC FOX Works

How It Works

The core idea behind AC FOX is both ingenious and remarkably simple. You start with a big, rotating tube. The size of the tube depends on the size of the waste stream you have. If the waste stream is small, the tube might be the size of an office desk. If your waste stream is huge, the tube could be as big as a tractor trailer.

You then fill the tube with activated carbon. Activated carbon is nothing but charcoal that has been "activated" to give it more surface area. It's the black granules that you find in aquariums and gas masks, and it's a completely safe, organic product.

The tube is motorized so that it rotates and stirs the carbon granules. This rotating tube full of activated carbon is the AC FOX reactor.

Now you take your wastewater stream and inject it and a source of oxygen (typically air) into the reactor. What happens next is the key to AC FOX. Here are the steps:

  • The activated carbon has a huge surface area (5 million square feet per pound), and that surface area grabs hold of all of the organic molecules in the wastewater that you injected.
  • Because the reactor is hot, the oxygen that you injected wants to react with something.
  • All those organic molecules trapped on the surface of the carbon granules are an easy target for the oxygen atoms inside the reactor.
  • The oxygen reacts with the organic molecules.

The reaction is very fast, and it produces three things:

  1. Carbon dioxide and water vapor from the reaction of oxygen with the organics
  2. Lots of heat, which boils off the water in the wastewater and keeps things hot
  3. A little ash containing mostly nitrogen and other inorganics in the waste

The ash is a great fertilizer, and the excess heat can be used anywhere that you need it in your factory. Or, you could use the heat to generate steam and drive an electric generator.

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With an AC Fox reactor, we have taken what used to be sewage and we have turned it into fuel.

The AC FOX reactor can do even more. It turns out that there are lots of places in factories that use activated carbon for filtering. Refineries, for example, use lots of activated carbon in their filters. The carbon granules do their filtering by adsorbing and holding onto molecules (see How Gas Masks Work for details). Once the carbon granules in a filter get "full," you have to either throw them away or "reactivate" them.

With AC FOX, you have a reactor that is perfectly suited to reactivating carbon. You load the reactor up with spent activated carbon, let the AC FOX reactor do its normal thing, and then take the carbon back out a day later. The newly reactivated carbon is ready to go back into the filter. This ability to reactivate carbon can also save factories a huge amount of money.

If you have a factory or process that currently produces a stream of organic wastewater, you are probably dealing with the wastewater as "sewage". If you use an AC FOX reactor instead, the wastewater turns into "fuel":

  • You "burn" all the organics in the wastewater in a bed of activated carbon and capture the heat from the reaction.
  • The heat comes out in the form of steam, which you can use anywhere in your factory.
  • After using the heat, you can condense the steam and reuse the water in your manurfacturing process.
  • In addition, you can use your AC FOX reactor to reactivate carbon for filtration.

AC FOX is a great way to turn lemons into lemonade.

AC FOX has an estimated payback period of less than two years. If you can use the AC FOX reactor to reactivate carbon as well, the payback period is even shorter.

AC FOX is the invention of Hugh McLaughlin, Ph.D. The AC FOX reactor is currently being used several factory environments and licensing rights are available. You can learn more by visiting

For additional information on AC FOX and related topics, please see the links on the next page.