Research Project Summary Information
Integrated Multistage Supercritical Technology to Produce High Quality Vegetable Oil and Biofuels(ST9462-1)
Proposers hoped to produce biodiesel with a continuous integrated process, starting with oil extraction from soybeans in multiple extractors and cascaded separators. The extraction step used three parallel batch extractors with supercritical (SC) carbon dioxide (CO2), and multiple CO2recovery stages. The biodiesel production step used SC alcohol in a continuous tube reactor and did not need catalysts. The process used a portable biodiesel generator to provide power and heat.
The goal was to develop an industrial process for continuous soy oil production, and couple that process to biodiesel production using SC alcohol. Additional Stage Two work is needed and would include design, construction, and operation of a pilot plant.
Lower production costs are possible with an integrated process. SC biodiesel production could reduce residence times from hours to minutes, and reduce the number of steps, including separation, purification, and/or recovery of biodiesel, alcohol, and catalyst. Glycerin, normally a byproduct of biodiesel production, would be thermally decomposed into combustible products that are soluble in biodiesel. The process can use aqueous ethanol, eliminating costly distillation. SC CO2 is more environmentally friendly than the compounds currently used to make biodiesel or extract soy oil.
Specific Stage One objectives included:
1) perform a literature survey for the components of the integrated system
2) design an integrated process
3) determine the reaction parameters and yields at lab-scale, and
4) determine and compare economics with current methods.
Stage One objectives were accomplished. Several hundred literature references were surveyed, the lab-scale process was designed and operated, and the oil extracted from soybeans with SC CO2 was of much higher quality than the hexane-extracted oil. The reported disadvantage of CO2 is that very high pressures (600-800 bar) are required to achieve sufficiently high oil solubility. Still, the project demonstrated 90% soybean oil extraction yield at 400 bar and up to 100 degrees C. The cost of biodiesel production via this technology was calculated for three technology options, and ranged from $3.46 per gallon to $2.49 per gallon, which could be competitive with current diesel fuel prices.
This work was a preliminary research effort. Further investigation is needed to develop and commercialize the process.
151 Link Hall Dept. of Civil & Env. Engineering Attn: Linda Lowe
Syracuse, NY 13244
Indigenous/Renewable Energy Resources
NYSERDA Contact Information
R&D - Environment & Energy Res