Cellulosics and the EU: chasing higher rates, yields, and more value from lignin

September 25, 2014 |

ligninThis week, while much of the world descended on New York to welcome the UN opening sessions and debate about climate change — we headed for ICLE4 — the International Conference on Lignocellulosic Ethanol, in Landshut, Germany — as a way of catching up with the lively cellulosic scene in the EU.

Here’s our report from the front lines.

The cellulosic scene in the EU is lively and well — greatly cheered by news of commercial-scale openings by POET-DSM, and Beta Renewables and the impending openings at Abengoa Bioenergy and DuPont.

This week, the 4th ICLE conference for cellulosic ethanol is taking place in Landshut, Germany — not far from Munich, and the mood is decidedly upbeat. A surprisingly strong turnout from Latin America might be the cause — delegates were on hand from Colombia, Chile, Brazil, Mexico, the Dominican Republic, and Uruguay. Many of the conference attendees managed to sneak in a plant tour at Clariant’s demonstration plant in nearby Straubing.

Given that the conference focused on cellulosic ethanol — many of the forestry-based companies like UPM that were focused on gasification technologies and drop-in fuels were understandably absent, but otherwise a who’s who of consortia and technologists were on hand — Corbion, KE Leuven, Cargill, Process Design Center, Praj, DONG (Inbicon), Borregaard, Terranol, Andritz, De Smet, NexSteppe, LNEG, Vireol, C5 Lignol Technologies, Poyry, Codexis, Maxbiogas, Ab Enzymes, Toray and a dizzying array of consortia, universities and government rR&D and regulatory agencies.

The general situation in the EU

In the EU, the sector is longer on technology than project sites — generally, there’s focus on the Asian market, the North America and that “ground zero” of bioenergy, Brazil.But there are projects that have bubbled along in the EU, don’t kid yourself, many of them backed by grants from regional authorities of the EU itself. Lots of pilots and some demonstrations afoot. The one large commercial-scale cellulosic project on the books for the time present is the Beta Renewables project in Crescentino, Italy.

We expect that to change in the next month, though. Watch this space for details.

Affordable, available feedstocks can be a headache

The feedstock of choice in the EU is generally wheat straw, though there’s corn stover available in pockets. One finds quite a lot of testing with bagasse in the EU labs these days.

Microorganisms a strength

A traditional strength for the EU has been in microorganisms — whether it is enzymes, yeasts or bacteria for fermentation, one finds a clutch of EU companies crowding each niche. There are the big guns in yeast like DSM, or the upstarts such as Taurus Energy which is making waves with its TransFerm line, and LeSaffre’s Leaf Technologies unit has landed a huge partner in Beta Renewables. In enzymes, the major players such as Novozymes and DuPont (which acquired Danisco a couple of years back) are releasing product almost every year, and it is not just a case of falling costs — but higher yields and better organism-biomass ratios.

But companies like US-based Dyadic have major lab operations in the EU and that’s a key partner in enzymes for Abengoa. And Clariant produces all the yeast and enzyme organisms for its partners as an integrated part of the sunliquid cellulosic technology package. That’s been getting a lot of attention in places like Brazil where infrastructure is less suited to trucking enzymes in as a no-brainer.

The big trend: deploymerizing lignin, finding high-value C5 products in search of higher value

The search is on for higher value — it’s the solution for smaller-scale projects and higher-cost feedstocks: make more from the products. Ethanol value is a given and the yields, while rising, are already to the point where we can expect improvement rather than revolutions.

Let’s review the science. With cellulosic feedstocks you generally have: C6 sugars (think “glucose”), that’s the cellulose; C5 sugars (collectively “pentose” — but they come in a variety pack including arabinose, xylose and galactose); and the lignin, a complex set of molecules that give rigidity to plants.

It has been infamously and often stated that “you can make anything out of lignin, except money”.

In every cellulosic fuels venture, the C6 sugars, from cellulose, are being fermented to make ethanol. In many of them, the C5s are also being converted — which requires some well-engineered yeast or bacteria to do, but most companies that need a solution, have one.

But, consider, for example, xylitol. It’s a 5C sugar that finds use as a diabetic sweetener. So, Praj for one, presenting at ICLE this week — said that they are looking at xylitol as a potential secondary product.

But the bigger trend has been looking for value in lignin. Right now, it is generally burned to provide process heat and steam — and in some cases, to produce green electricity to sell into a grid. The highest value we’ve seen is around $660 in lignin value, per ton of ethanol. That’s from Beta Renewables, which is generating 3.3 MWh from the lignin that comes in with their five tons of biomass that they ultimately converting into one ton of ethanol. That $660 is in Italy, which has sky-high prices for green watts — in California, the same process produces half that value.

Which is to say that, right now, the value of lignin — if you have a green electricity market available — runs around $140-$275 per ton. That’s if you have excess lignin available. For purposes of comparison, the value of ethanol is in the $630 per ton range. Green chemicals can run double, or triple that. For selected, exotic molecules — even more.

The upside

So, you get the idea. There’s real upside there. Given that some 40% or more of a given cellulosic feedstock can be lignin. Even if you feel off just 10% or 20% of the lignin with your deploymerization technology, you can generate real dollars — after all, even a small commercial facility in cellulosic fuel is bringing in 100,000 tons of biomass. That’s 40,000 tons of lignin – so if you see $40 million in added revenue by upgrading $150 lignin to $1150 chemicals, well that’s the correct math.

So far, no technical breakthroughs, but the work is on in the lab — with a goal of deploymerizing the lignin, which is to say, reducing a complex set of molecules to a smaller and simpler set that can be purposed for fuels or chemicals. For example, the BTX set of aromatic molecules – benzene, toluene, xylene — lots of value in there.

Look at the attention that Virent, Gevo and Avantium have generated for paraxylene, which is the missing ingredient in the search for the 100% renewable clear plastic bottle.

Now — given the complexity of lignin — it’s far too early to focus in on a set group of molecules and say: “this is the target”. We’ll know more down the line. And a lot of fine minds have attacked this problem before.

The key is, the search is on. One thing to remember, white rot fungi do a very good job of breaking down lignin. Figuring out how they do it, and reassembling that at a higher rate — well, that’s certainly one good way to go. Point is, nature can do it…slowly. Nature converts biomass to fossil oil, too…slowly. Nature does a lot of things slowly that we would like to hurry up — and don’t always dial up a solution for.

But the hunt is on, with purpose.

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