ARS | Publication request: SINGLE-PASS, SPLIT-STREAM HARVEST OF CORN GRAIN AND STOVER

Submitted to: Transactions of the ASABE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 1, 2007
Publication Date: March 1, 2007
Citation: Shinners, K.J., Adsit, G.S., Binversie, B.N., Digman, M.F., Muck, R.E., Weimer, P.J. 2007. Single-pass, split-stream harvest of corn grain and stover. Transactions of the ASABE. 50:353-363.

Interpretive Summary: Corn stover (the remainder of the plant after removing the grain) could be another feedstock for producing ethanol if it could be harvested economically. A key to this is harvesting both grain and stover in as few steps as possible. In this study, a harvester capable of recovering both corn grain and stover in a single pass was designed and tested. Whole-plant harvesting was considerably slower than conventional grain harvesting, but good recoveries of both the grain and stover fractions were obtained. Up to 90% of the individual non-grain components (leaves, stalks, husks and cobs) of the corn plant were recovered, and the estimated ethanol yield of the recovered product ranged from 2600 to 3945 liters per hectare, depending on cutting height. The results indicate that single-pass harvesting may provide corn producers a simple and viable method for harvesting both grain and stover fractions.

Technical Abstract: A grain combine was modified to produce single-pass, whole-plant corn harvesting with two crop streams: grain and stover. Capture of potential stover DM varied from 48 to 89% for leaves, 49 to 92% for stalks, and greater than 90% for husks and cobs, depending upon corn head height. Stover aggregate moisture was 50.2, 43.1 and 36.4% (w.b.) when the corn head height was 10, 44 and 63% of ear height, respectively. Feedrate of materials other than grain limited ground speed due to power availability, so area capacity was 2.3, 2.8 and 3.4 ha/h when corn head height was 10, 44 and 63% of ear height, respectively. Whole-plant harvesting reduced area capacity by nearly 61% compared to harvesting with a conventional snapping-roll head. Single-pass stover had an average particle size of 69 mm and bulk density of 51 and 110 kg DM/m3 in the wagon and bag silo, respectively. Based on polymeric sugar content, estimated ethanol yield was 3,945, 3,230, and 2,600 L/ha when the corn head height was 10, 44 and 63% of ear height, respectively. Fermentation of single-pass stover in a bag silo was adequate with average losses of 6% of total DM.