Environmental Impact Analysis of Soybean Oil Production from Expelling, Hexane Extraction and Enzyme Assisted Aqueous Extraction

Abstract

<p>In the industry, expelling and hexane extraction are the two typical processes for soybean oil production. However, the low efficiency and hazardous chemical problem are the main issues for these two processes respectively. Enzyme assisted aqueous extraction process (EAEP) is applied to increase the efficiency without using organic solvent, which is replaced by water. The environmental impact analysis of these three processes are based on their mass flows, energy consumption and global warming potential. For mass flows, the environmental impact indices were calculated based on mass balance of input and output components. Energy consumption was used to evaluate the carbon dioxide and greenhouse gas (GHG) emissions. According to results, hexane extraction has the highest environmental impacts due to the application of organic solvent; EAEP has the highest CO₂ and GHG emissions because of more requirements for soybean flaking processes.</p>