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How AC FOX Works


The Advantages of AC FOX
The Activated Carbon Facilitated Oxidation reactor, or AC FOX, is a way to use waste for energy. Learn what processes could benefit from it. HowStuffWorks
The Activated Carbon Facilitated Oxidation reactor, or AC FOX, is a way to use waste for energy. Learn what processes could benefit from it. HowStuffWorks

So let's go back to our ethanol factory. The factory creates 10 gallons of wastewater for every gallon of ethanol that it produces. The wastewater contains proteins, sugars, enzymes, DNA fragments and a little left-over alcohol.

How do you get rid of this wastewater? Ethanol plants today usually handle it by evaporating the water and making animal feed from the solids that are left behind. The sale of the animal feed does not cover the cost of evaporating the water, but it does solve the wastewater problem.

Another way to handle the wastewater is to treat it like sewage. Let's look at the sewage approach, since that can be applied to all waste streams that we are talking about. With sewage, you let the water stand in large tanks or holding ponds and you let bacteria eat all the organic material in the water. That works, but there are three problems:

  1. The process often takes a lot of space
  2. The bacteria are slow
  3. The process completely ignores the fuel value of the wastewater

The third problem is key. Any stream of wastewater contaminated with lots of organic material like sugars and proteins can be thought of as a waste fuel. If you could somehow burn this fuel, you could use the resulting heat to do all sorts of things. You might use the heat in part of your manufacturing process, or use it to generate steam and make electricity. One great thing about this heat is that it would be free. Currently you are letting the bacteria eat that fuel, and it is all going to waste.

It turns out that, up until this point, burning wastewater has been impossible. Imagine trying to burn pancake syrup. Pancake syrup contains a huge amount of energy because of all of the sugar, but up until now there has been no way to "burn" it because the water in the syrup makes burning impossible. Even if you dehydrate the syrup and try to burn the dry sugar, it doesn't burn very well.

AC FOX completely changes the equation. The goal of AC FOX is to quickly and efficiently "burn" all of the fuel in any stream of organic wastewater. With AC FOX you can, in fact, "burn" pancake syrup and capture all the heat. You can also "burn" the effluent from your ethanol factory, or glycerol, or water with lots of pizza crumbs dissolved in it. Any organic wastewater stream turns from "sewage" (which is a problem) into "fuel" (which is cool) if you have an AC FOX reactor in your factory.

By "burning" your wastewater, you now have an asset instead of a liability. You can use the free heat created by the AC FOX reactor anywhere in your factory. You can also immediately reuse the water, because it is clean. And you also speed up the whole process. Instead of letting the wastewater stand for days in a settling pond or bacterial digestion tank, you can "burn" the wastewater quickly, as soon as you create it.

Now you can understand why manufacturers are starting to get so excited about AC FOX. Next, we'll see exactly how it works.


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