Solvent Extraction for Vegetable Oil Production: National Emission Standards for Hazardous Air Pollutants (NESHAP)
This industry is comprised of facilities that produce crude vegetable oil and meal products by removing oil from oilseeds through direct contact with an organic solvent.
The extraction process is the same for all eight types of oilseeds subject to this rule (soybean, cottonseed, canola, corn germ, sunflower, safflower, peanuts, and flax). In each case, the seeds are crushed and mixed with the solvent. The oil then dissolves in the solvent. Following this step, the solution is separated from the seeds and heated to evaporate the solvent. The evaporated solvents are then condensed and reused in the process.
The National Emissions Standards for Hazardous Air Pollutants (NESHAP) for this sector was originally proposed in 2000 and promulgated in 2001. Amendments were made in 2002 and 2004. In these actions, the EPA identified n-hexane as the HAP emitted in the largest quantity from the solvent extraction process in vegetable oil production. This standard restricts plant-wide hexane emissions from each affected facility rather than requiring individual controls at each emission point.
See the regulations in the section below for more details.
04/12/2001 - Final Rule
05/26/2000 - Proposed Rule
Applicability Determination Index (ADI). The ADI is maintained by EPA's Office of Enforcement and Compliance Assurance (OECA) and provides a data base of memoranda dealing with applicability issues. The database is searchable by Subpart.