Crop Biotech Update

Life Cycle Assessment Study on the Production of Both Bioethanol and Bio-Oil from Corn

November 25, 2011
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Researchers from the Iowa State University (United States) report the use of a slightly different approach to the Life Cycle Assessment (LCA) study on biofuel production from corn. In their study, they looked at the "per-unit-land-area"-based (rather than "per-unit-energy"-based) LCA for the production of two types of biofuel production pathways from corn: (1) bioethanol from the processing of corn starch and (2) a refinable "bio-oil" for biogasoline production (with a "biochar" solid by-product) from the thermal (pyrolytic) processing of cornstover (stalks/leaves after harvest). Here, not one, but two biofuel feedstocks from a single bioenergy crop (the corn plant) are utilized for biofuel production:  (1) the starchy corn grains for bioethanol, and (2) the lignocellulosic cornstover for pyrolytic "bio-oil" production.

The motivation behind the use of the "per-unit-land-area" basis in LCA stems from the observation that the common LCA method using the "per-unit-energy"basis has some limitations. According to the authors, "a significant shortcoming of this approach to current LCAs is that they do not allow emissions measurement for a biofuel pathway that utilizes more than one feedstock. In agriculture, specifically, it makes sense to consider the possibility of utilizing more than one feedstock for biofuel production given that land is a scarce resource". The results of their study showed that the "two biofuels-one energy crop" pathway for biofuels production from corn achieves a 52.1% reduction in GHG emissions, and that this production pathway could qualify as an "advanced biofuel". The complete study is published in the journal, Fuel (URL above).