"Cornucopia Biorefinery": Food, Fuel, Fertiliser from Corn

The key to early profitability for bioenergy producers is to make use of as much of the feedstock as possible to produce as many profitable products from the feedstock as possible. Here is one such approach:

The SynGest Cornucopia model takes an entire ear of corn and simultaneously produces The Three F’s: food, fertilizer and fuel. This is why we have adopted the slogan: “You can have your fuel and eat it too…”. With Cornucopia, there is no more compromise between food vs. fuel…and we get enormous amounts of nitrogen fertilizer in addition. The Cornucopia model is mainly a re-engineering or re-design of how we process an ear of corn. When we use the kernels as food, we use them whole which is not ideal for many of the animals that we feed, especially cows. When we make ethanol, we waste the valuable food and the cellulosic parts of the kernel. Also, today, we throw away the valuable cob. The goal is to use every part of the corn plant that can safely be removed from the field year after year.

...Cornucopia Detail

1. “Slipstream” biomass harvesting is based on the recognition that if we want to harvest large volumes of biomass (which includes cellulose and starch) for biofuel and bioproduct production, we must leverage the enormous farming activity that already exists worldwide. In the U.S., the major crop is corn. The normal harvesting technique is to allow the corn to stand in the field till late in the fall and then use a combine to only harvest the kernels. The model that we have adopted is to simultaneously harvest the kernels and the cobs (partially broken) in the same grain bin. An inexpensive $2,000 modification to the typical combine unlocks this opportunity for the farmer.

...2. Dry fractionation is also known as dry milling. This is in fact the front end and first processing stage of the entire Cornucopia BioRefinery. The corn kernel is separated into its three main components of corn starch, germ and bran. The starch is sent to the fermenter and the germ is sent to the oil extraction facility. The corn cobs collected as noted above are also delivered and mixed with the residual bran and becomes a mixed cellulose stream for the gasifier (see below). Each component is processed using a different technology to maximize its potential.

...3. The fermentation facility which today is an ethanol plant, efficiently converts the starch into fuel. Fermentation is the most efficient way at our disposal to produce fuel from sugar and starch. The Cornucopia BioRefinery recognizes this and takes advantage of the maturity of this technology. Early rollouts of Cornucopia BioRefinery may in fact include ethanol fermentation as the fuel product. However, as soon as possible, it is recommended that ethanol nbe replaced by one of the new technologies that produces “drop-in” (fully fleet and infrastructure compatible) fuels. There are a number of offerings that are near-commercial from companies like Butamax, Gevo, Cobalt, Amyris, Optinol etc

...4. The gasification facility is the only really “new” technology in the Cornucopia BioRefinery. The SynGest gasifier, although it has some new characteristics and achieves better performance than prior biomass gasifiers, it is based on well-known and understood technologies. The goal with the SynGest system is to convert any form of biomass into clean syngas at the lowest possible cost and simplest operational approach. The ideal scenario would be to convert biomass into syngas in one step. The best way to come close to achieving that goal is to gasify the biomass using almost pure oxygen and the appropriate catalytic fluidized bed. Although our design gets very close to complete conversion in one step, we still have components of the syngas that need to be handled, such as methane, tars and BTX. In the past, the approach has been to include a “clean up” stage to remove these unwanted gas components. Not only are these clean up approaches costly, they reduce the overall conversion efficiency. The SynGest approach instead adds an autothermal catalytic reformer, also enhanced with oxygen. This second stage of the gasifier converts all of the tar and BTX into syngas and almost all of the methane as well. The net effect is that rather than having a costly clean up stage and a toxic waste issue, SynGest has substituted a low cost yield enhancement device and removed the waste problem in its entirety.

...5. Food grade oil extraction is another critical technology to achieve maximum financial and social value of the Cornucopia BioRefinery. The germ fraction is processed in a food-grade oil extraction process. Although there are other techniques in the market, and the historical approach uses hexane (a nasty carcinogen), SynGest has developed a clean and low cost alternative to pulling the oil out of the germ. We use a specific mix of two food-grade solvents (GRAS) that has a natural affinity for the corn oil. The chemical pull of this solvent mix is so powerful that greater than 96% of the oil is pulled out of the germ without the need for mechanical processing. The oil is then easily separated from the solvents which are then recycled and used again for the next batch. The residual of the germ is an already dry and de-oiled high value and high quality protein. This protein can be fed to humans but more importantly can be fed to all of the types of animals that we like to eat.

...Input. 245,000 acres of corn.

Fuel. 132 million gallons of fuel. A typical 110 million GPY ethanol plant, when retrofit to ferment starch vs. whole corn, will produce 20% more fuel per year for a total of 132 million GPY. At the same time, the cost to ferment is lower so a given capital investment will make more fuel at a better margin per gallon.

Food. 71 million Lbs of food grade corn oil and 74 thousand tons of high grade protein. A 132 million GPY plant as noted above will use approx. 245,000 acres of corn (200 bushels per acre). From that corn, 71 million Lbs of food grade corn oil will be produced and 74 thousand tons of high grade protein.

Fertilizer. 500,000 acres of corn. Of the bran and cobs, 50,000 tons of anhydrous ammonia (nitrogen fertilizer) will be produced. This will be enough for 500,000 acres of corn or twice as much fertilizer that is needed to fertilize the corn that feeds the Cornucopia BioRefinery. We will be able to fertilize the Cornucopia BioRefinery operation and an equal number of acres beyond for entirely other uses. _BiofuelsDigest

We are still in the earliest stages of learning to maximise our output and minimise our input for efficient and wide-ranging production.

The choice is not between food and fuels, but rather between food alone and food plus a wide range of other valuable products including fuels.