In the struggle to use corn for biofuels without actually using corn for biofuels, US researchers are now paving the way for the use of post-harvest corn residue as a potential biofuel source.
Corn crop residue often left behind on harvested fields to protect soil quality could become an important raw material for cellulosic ethanol, US researchers say.
A study by scientists with the US Department of Agriculture (USDA) indicates that soil quality would not decline if post-harvest corncob residue was removed from fields.
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“We didn’t have data on how post-harvest cob residues might protect soil quality. But corncobs make up 20 percent of residue by weight, which means that the average U.S. production of corn could provide 40 [million] to 50 million tons of cobs for feedstock every year,” according to USDA soil scientist Brian Weinhold.
Stover is comprised of the leaves, husks, cobs and stalks of the corn plant, and could provide an abundant source of feedstock for cellulosic ethanol production after the grain is harvested.
By removing a sustainable portion stover from the field, researchers avoid possible pitfalls such as erosion, depletion of plant nutrients and acceleration of loss of soil organic matter.
In fact, according some farmers, the removal of corn stover from their fields might be beneficial to crop production in the end. Farmers are claiming that stover is becoming a real nuisance that is costing them a lot of time and money to manage.
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A new DuPont facility currently under construction in Nevada, Iowa, is expected to generate 30 million gallons annually of cellulosic biofuel produced from corn stover residues once it is completed in mid-2014.
However, removing corn stover from agricultural fields to produce cellulosic ethanol requires careful management to avoid adding greenhouse gas emissions and soil erosion to the environment.
Environmental impacts can be reduced by switching to no-till corn or adding winter cover crops, but these practices likely would increase production costs.
US corn crops could potentially reach 100 million acres in 2030 with 300 bushels per acre.
By. Joao Peixe of Oilprice.com