Scott Kohl is Vice President of Technology and Process Improvement at White Energy, a biofuels producer based in Texas. We caught up with him at the World Ethanol & Biofuels conference to find out how ethanol production technology is improving, and why DDG fractionation can help to command higher prices from the animal feed market.
“Separating the distiller’s grains into an oil rich or 100% oil fraction, a protein rich faction and a fibre rich faction, you can make a better feed for animals and command higher prices. So the ethanol industry will make more money on it, and the animal feed industry will have better feeds to use on their operations, and make more money as well. It’s a win for everybody.”
If you look at the past five years in ethanol production, what are the most important advancements you’ve seen?
“In the past five years we have seen tremendous improvement in yeast technology. Yeasts today can make enzymes – gluco-amylase – and they have higher yields because of metabolic pathway shifts, either genetically enhanced or naturally they were better base strains. That’s probably the biggest change I would say in the last two to three years.
“And if you go back five years the advances in enzyme technology have been striking as well. We have lower PH tolerant enzymes, which increases both the yield of the plants as well as reduces nitrogen loss, and does a better conversion of starch to ethanol. And then we’ve also seen advantages in mechanical processing that allow higher fermentation yields through processes like selective grind technology, selective milling technology, processes that are basically borrowed or adapted from wet milling into the fuel ethanol plants.”
We’ve heard a lot about cellulosic ethanol in the previous sessions. I’m wondering – if there’s to be a breakthrough in cellulosic ethanol, where will it come from? Will it come from something like an enzyme breakthrough, through a physical process in the plant – where you do you see that happening?
“My opinion is for ethanol from cellulose to really become part of our production, we have to go after the fibres naturally present in the grain – use corn as an example. If you look at all of the hurdles to make ethanol from cellulose, many of the hurdles don’t exist for corn kernel fibre because you already own it when you buy the corn, you already have good quality control, there’s no shipping to do, it’s already there. And you already have an ethanol plant there.
“So I think my feeling is that the enzymatic route will be the most successful there, but it doesn’t have to be. It can be a chemical route, to make the sugar from fermentation. But I really think if we can’t do grain fibres, whether it’s wheat fibre, or sorghum fibre, at the plant doing it from harder to process materials like stovers and straws will be less successful. I think once we’re successful on fibre conversion in the plant we can then take that learning to corn stovers and wheat straws and the like.”
And if you look at the processes used in White Energy’s ethanol plants, are they different in some way from other ethanol producers in the US and elsewhere?
“They’re really similar. I mean every plant has something a little different that they do, but they’re really for the most part pretty trivial in the grand scheme of things. The only thing that White Energy really does differently is that we have a hybrid fermentation process, where it’s a cross between a batch process and a continuous process. Otherwise the technologies that we have or the processes that we use are used elsewhere in the industry, maybe often.”
You’re also speaking at the Distillers’ Grains Summit on Thursday. How can fractionation be used to increase the value of the co-products that come from ethanol production?
“So, distillers grains as an aggregate are not really a great feed for any animal segment. It has too much protein for cattle, it has too much fibre for swine and for poultry, it has too much fat for swine and too much fat for dairy. So as a mix it’s just a cheap feed. It’s good, but it’s not great. If we can pull that apart, and concentrate the protein in one container, or one bucket if you will, and leave the fibre behind in the other one, the fibre is great for cattle. They digest it very well. So they will do well on that feed. And then the higher protein that’s depleted in fibre, would be a great feed for chickens and for swine.
“So you’re basically taking a material that is not really well suited for any animal, and breaking it into the components that make it valuable to both species, and for the chicken and the swine you minimise the manure problem. So if distillers grains are a third fibre, you have a tremendous amount of manure for poultry and swine, which is a detriment. Whereas for the cattle their protein is too high and their fat’s too high. So separating the distillers grains into an oil rich or 100% oil fraction, a protein rich faction and a fibre rich faction, you can make a better feed for animals and command higher prices. So the ethanol industry will make more money on it, and the animal feed industry will have better feeds to use on their operations, and make more money as well. It’s a win for everybody.”
