Making something from nothing

The cellulose-to-sugars process is expanding bioethanol feedstocks to a more ecofriendly alternative.

Cellulose extraction processes like CTS pull waste products from agriculture residues, lumber mills, landscaping and landfills to create renewable fuels.

Biofuels are booming. Investment and development of bioethanol has increased significantly as ecoconscious consumers look for an environmentally friendly fuel solution. Throughout the last few years, we’ve witnessed a significant focus on research and production of biofuels, particularly cellulosic ethanol, to identify a commercialized solution that is affordable for both producers and consumers while not interrupting the food chain.

According to reports by Allied Market Research, Portland, Oregon, the value of the global bioethanol market is expected to reach $9.54 billion in the next five years—nearly double its valuation of $5.6 billion in 2015. This projected market growth is just another example of how invested researchers and consumers are in identifying an energy option that alleviates us from our dependency on carbon-based fuels. One of the approaches individuals are taking is the inclusion of common waste products in the ethanol production process.

FINDING THE ECOFRIENDLY BALANCE

When most people think of ethanol, they assume it is a clean fuel, particularly when it’s compared with petroleum, and therefore identify it as the ecofriendly solution. While ethanol has fewer carbon dioxide (CO2) emissions, there are other parts of the process that can affect the environment, including what is being used as feedstock for sugar production.

For traditional ethanol production, corn is the most common feedstock used, as it is relatively easy to grow in the large quantities required to produce the amount of sugar needed for commercial efforts. As demand has increased, the need for more feedstock has followed suit, leaving producers with a difficult decision: pulling more corn from our nation’s food supply, reverting to petroleum or identifying a new form of feedstock that does not interfere with food sources.

Some producers are choosing to pursue the latter by extracting the necessary sugars from cellulosic waste. This material is plentiful and can be found anywhere in agricultural operations, such as discarded stalks, leaves and other items, and in residential or commercial applications, such as yard clippings, paper and wood chips. The challenge is in extracting the cellulosic material at a cost that is affordable to producers and consumers alike.

A CELLULOSE TO SUGARS JOURNEY

New technology is making this transformation of cellulosic waste into low-cost, high-efficiency biofuel possible by simplifying a traditionally complex process. Through innovations such as new cellulose to sugars (CTS) conversion efforts, a broader portfolio of materials is capable of being converted to ethanol, meaning producers have expanded resources to pull from for production.

CTS is a simple mechanical process that converts any cellulose material into inexpensive sugars, which can then be used to create cellulosic ethanol or other products, including fine chemicals, construction products, pharmaceutical or nutraceutical products and carbon fiber nanotubes. By combining common waste with a proprietary dry catalyst in a CTS reactor, a mechanochemical reaction is created within minutes, breaking down the cellulose into its base components of C5 and C6 sugars plus pure lignin. The costs for this process are leaned out even further by the elimination of additional process components, including expensive enzymes, liquid acids, applied heat or pressure.

On the surface, ethanol is the same whether it’s made from corn, yard clippings or any other type of waste. As a result, it performs the same when used as fuel. However, what makes CTS cellulosic ethanol unique is its versatility and the ability to create it from nonfood sources on nonfarm lands in larger quantities and at lower costs. This flexibility is leading to wider acceptance and use. The racing industry, including NASCAR and Indy Car, has adopted ethanol as its primary fuel source because of its high performance and remarkably low greenhouse gas emission. Ethanol’s applications are far reaching and can be seen in jet and diesel fuel, as well as in industrial grade alcohols.

COMPARING COSTS

The economic benefits of ethanol produced with cellulosic waste, namely reduced costs and higher profit margins, are easy to identify when compared with other types of ethanol. It currently costs approximately $1.30 to $1.60 to produce a single gallon of ethanol through traditional methods, though that price can fluctuate depending on the market price of corn at a given time. Other enzymatic cellulose processes feature production costs as high as $4.50 per gallon, also depending on the market price of corn stover, the waste product from corn farmers.

Cellulose to sugars is a mechanical process that converts any cellulose material into inexpensive sugars, which then can be used to create cellulosic ethanol.
Using organic waste and processes such as CTS enable producers to bring the cost of production down to less than $1 per gallon of cellulosic ethanol, and that is projected to decrease to less than 80 cents per gallon—a cost that has yet to be achieved by an American ethanol producer. This is roughly equivalent to about $18 per barrel of oil, a price that has not been seen in the U.S. for decades.

In addition to leveraging the efficiencies of these forms of cellulose extraction, ethanol producers can take other operational measures to ensure further cost effectiveness. For starters, producers can locate their facilities strategically. The closer a facility is to its raw material source, the less overhead it will incur in the areas of procurement and transportation.

Strategic location is a much easier task for facilities using organic waste. Because cellulosic ethanol processes like CTS use feedstock that is agnostic, meaning it uses waste found almost anywhere, it is viable in a wide range of geographical areas and does not require large refinement or distribution networks. This common waste usually is expensive for communities to dispose of, so it is in everyone’s best interest to have ethanol producers remove it and use it.

The efficiency of mechanical cellulose extraction processes, the lower costs in sugar extraction and ethanol production as a whole make reduced operating expenses possible.

On average, ethanol produces 85 to 90 percent fewer greenhouse gases than traditional petroleum-based products, is less volatile and has lower fumes. The current dry mill corn process consumes large amounts of water, electricity and natural gas, in addition to creating thousands of tons of CO2 and residual fiber waste.

The use of cellulose extraction process such as CTS, however, pulls common waste products from agricultural residues, lumber mills, landscaping and landfills to create simple sugars. By using a low-energy mechanical conversion process, no enzymes, applied heat or pressure are required, which revives the waste and gives it a second life. This elimination of waste means fewer waste items in landfills, less pollution and more space.

In addition to the reduction of CO2 resulting from less materials rotting in landfills, these types of processes ultimately consume CO2 instead of creating it. While consuming very little energy, it creates a carbon-neutral footprint and a fuel product that markedly is cleaner than more conventional products.

WILLING AND ABLE

Over the next several years, you will likely see many biofuel plants incorporating waste materials and the accompanying cellulose extraction technologies into their processes. This shift from using corn will not only help to reduce fuel costs but also will reduce the costs of thousands of products containing corn.

By the end of the next decade, it’s possible that ethanol will be created that meets the Renewable Fuel Standard threshold. In the next two decades, we completely could replace petroleum gasoline in the U.S. with waste-based ethanol. Enough green waste is available in our municipal systems to allow us to do it if we’re willing to.

Daniel de Liege is the chairman of Alliance Bio-Products Inc., West Palm Beach, Florida.

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