Breaking down biomass

Show caption
Bill Feig /
Advocate staff photo by BILL FEIG -- Electrician Jared Quigley works Tuesday on the cane milling train device, which extracts energy cane juice from the feedstock behind himt. LSU AgCenter is ready to start testing potential biofuels at its pilot plant in St. Gabriel. The pilot plant is part of five-year, $17 million project.

LSU AgCenter pilot plant to test biomass sources

The LSU AgCenter’s biofuels pilot plant has yet to begin operating, but the facility has already drawn the attention from at least two national biomass publications and a handful of biochemical companies.

“Interest is beginning to pick up out there, so it’s made a pretty big splash,” said AgCenter Vice Chancellor John Russin.

The plant, the only one of its kind in the United States and possibly the world, is the centerpiece of the AgCenter’s Sustainable Bioproducts Inititiative, Russin said. The project is funded by a five-year, $17.2 million U.S. Department of Agriculture grant.

The project’s goals include using research by AgCenter scientists to help companies convert sugar cane stalks and sweet sorghum into the building blocks used in making specialty chemicals, pharmaceuticals and polymers, Russin said. Research at the facility will also help develop the technologies needed for sustainable biofuels production from Louisiana crops and forests.

However, Russin said there’s little chance of getting rich making gasoline from bagasse, the residue from sugar cane.

Production costs for biofuels are too high to compete with gasoline at $3.20 a gallon, Russin said. The money will more likely come from specialty chemicals made from cane or sorghum.

The AgCenter hopes that the plant’s industry partners — Dupont, SynGest, MS Processes, Sugar Cane Growers Cooperative of Florida, John Deere, Ceres and Virent — will be able to achieve the kind of results with cane or sorghum that chemical companies already have with corn, he said.

“They break down corn starch right now, and they polymerize it and make all kinds of plastics with it,” Russin said. “Plastic drink cups, all your disposable plastic forks and plates, are made out of corn plastic.”

The pilot plant’s research on specific strains of cane and sorghum could do the same thing for the polymers inside bagasse, Russin said.

But in order to accomplish these ambitious goals, AgCenter researchers must first answer a lot of questions, said Vadim Kochergin, director of the Louisiana Institute for Biofuels & Bioprocessing.

One of the most important: How much can a bio company afford to pay farmers sustainably, year after year after year, to make it worthwhile for growers to consider planting energy cane or sorghum?

To answer that question, researchers must start with the cost of the end product and work backward to calculate how much buyers can afford to pay for the crops, Kochergin said. This sounds simple but quickly gets complicated.

The cost of production includes everything from the costs to operate the equipment; how to ensure a year-round supply of feedstock for a bioprocessor or biochemical company; how much of a certain crop can be grown; where it can be grown; when it can be grown; what that crop will yield, because the bigger the yield the less acreage is required, which also means lower transportation costs; how much the feedstock yield will vary, because one of the biggest problems with agricultural products is that crops can be affected by so many things, including the weather, fertilizer and the area planted; the best method to harvest the crop; whether to store the crop; how much to store; and the most efficient method of storing it.

Bill Richardson, the LSU AgCenter’s chancellor, emphasized that the pilot plant is not there to test food crops as a source for biofuels. He said the AgCenter does not want to do anything that would raise the price of feed for farmers and food for people the way the conversion of corn to ethanol has done.

Researchers are looking at different strains of sorghum and energy cane, or high-fiber sugar cane, which the USDA has identified as the regionally appropriate crops, Kochergin said. Although energy cane was the first crop picked for the Southeast, Kochergin believes sorghum may actually be the best crop for Louisiana and the United States.

Sorghum can be grown anywhere, unlike cane, which needs warmer weather, Kochergin said. His friends from Russia say sorghum can be grown 500 miles south of Moscow, the 53rd parallel; Louisiana is at the 31st parallel, or 31 degrees north of the equator.

Sorghum also grows quickly, in about 100 days, he said, and the new varieties and hybrids offer a lot of potential for improving production, Kochergin said.

Still, Kochergin said, cane and sorghum only grow six months out of the year, and a biofuels or bioprocessing plant has to operate 12 months a year to make economic sense.

So researchers are looking at the best ways to ensure a year-round supply of feedstock, Kochergin said. One promising idea is sugar syrups, which are stable and can be stored in large tanks.

Another challenge is figuring out how to supply the energy a bio plant needs to convert the feedstock, Kochergin said.

The cane residue, or bagasse, can be burned as a fuel or processed and turned into simple sugars, Kochergin said. The question is which is the more efficient use?

While burning the bagasse might produce excess power that can be returned to the grid, Louisiana utilities aren’t very good about buying that electricity, Kochergin said. And some people claim bagasse may have more value as a source of sugars because the price of natural gas as a fuel and feedstock is cheap.

The pilot plant will play a key role in answering those questions, Kochergin said.

The AgCenter Audubon Sugar Institute in St. Gabriel will hold a ribbon cutting at 10 a.m. Friday to mark the plant’s completion.

In the past several weeks, the AgCenter has fielded inquiries from Houston-based Chevron Technology Ventures; biobutanol developers Cobalt Technologies of Mountainview, Calif.; Green Biologics, of Gahanna, Ohio; and Myriant Corp., the Quincy, Mass.-based firm building a bio-succinic acid plant in Lake Providence. Succinic acid is usually made from petroleum-based feedstocks and used in polymers, fibers, detergents and flavors. Myriant plans to make the acid from sorghum and carbon dioxide.

Kochergin said that the pilot plant is a milestone that will attract a lot of attention. Until now, the AgCenter didn’t have much to show people besides a concept.

The average sugar mill in Louisiana processes around 12,000 tons of cane a day or 500 tons an hour, Kochergin said. The AgCenter pilot plant can process 1 ton of cane an hour.

Russin said the size will benefit crop breeders.

A crop breeder working on different strains of crops may have only a couple of small plots planted, Russin said. But no commercial sugar mill is going to keep a ton of cane, or the sugar produced from it, separate from the rest of the cane being processed because it’s not practical.

Kochergin said the pilot plant will also provide students with an invaluable experience in learning how a factory runs.

Until now, students interested in bioprocessing have to pick up the information in bits and pieces, a chemical engineering course here, a biological engineering course there, he said.

“There is no combined, coordinated effort,” Kochergin said.

But LSU, Southern University and the AgCenter are putting programs together that focus around biomass, he said.

A working sugar mill is so large it’s difficult to see how all the parts work together, Kochergin said. But the pilot plant is small enough that students can more easily grasp how a factory operates.

Kochergin said researchers look at the entire process as a road with different stops or challenges.

The process is complicated, but a lot of work has already been done in many areas, he said.

“What we’re trying to do is analyze this whole process from the standpoint where do we need to study more? And where has (the process) already been studied?” Kochergin said.

The researchers’ task is to identify the potholes and then pave them over to make the road smooth, Kochergin said.

Russin said enthusiasm about the pilot plant is running high, in some cases unrealistically so.

“We’ve gotten some calls from people who think that you put bagasse in one end and you get gasoline out the other,” Russin said. “But that’s not what it is.”

The AgCenter is doing its best to temper the expectations of people who don’t really know the scope of the project, Russin said. But the project is exciting.