Title: Life cycle assessment of soybeans production and processing system into soy oil using solvent extraction process

Authors: S.O. Jekayinfa; J.A. Olaniran; B.F. Sasanya

Addresses: Department of Agricultural Engineering, Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso Oyo State, Nigeria ' Department of Agricultural Engineering, Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso Oyo State, Nigeria ' Department of Agricultural Engineering, Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso Oyo State, Nigeria

Abstract: Agricultural operations have been indicated to be some of the major emitters of greenhouse gases (GHG), particularly methane (CH₄) and nitrous oxide (N₂O) around the globe, and it is important to determine the quantity emitted and how they can be reduced. The environmental impacts associated with field production and industrial processing of soybean into crude vegetable oil in Nigeria was therefore studied using the life cycle impacts assessment tool. The emission from the various inputs into the system was aggregated into a large inventory table. The functional unit was defined as one kilogram of soybean. The environmental impact categories used in this study are global warming, acidification, eutrophication and ozone layer depletion. Of these four environmental impacts, global warming has the highest impact score of 4.7516E-01 kg CO₂ equivalent, followed by eutrophication (1.6414E-04 kg NO₃ equivalent). Ozone layer depletion has the lowest environmental impact score of -2.8207E-07 kg R11 equivalent. The high impact score of global warming is due to the high emission of CO₂ gas from fossil fuel and biomass combustion during field operations and processing of soybeans.

Keywords: soybean production; soybean processing; life cycle assessment; LCA; environmental impact; soy oil; solvent extraction; vegetable oil; Nigeria; global warming; acidification; eutrophication; ozone layer depletion; fossil fuel; biomass combustion; soybeans; CO2; carbon dioxide; carbon emissions; air pollution.

DOI: 10.1504/IJPLM.2013.063203

International Journal of Product Lifecycle Management, 2013 Vol.6 No.4, pp.311 - 321

Received: 01 Nov 2012
Accepted: 27 Jun 2013
Published online: 26 Jul 2014 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article