Biodiesel Purification


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Thin-film processing enables continuous purification of biodiesel and glycerin

Artisan has developed a patented continuous biodiesel purification thermal separation process (U.S. Patent No.7,528,272 ), using our thin-film technology for pre and post reaction steps, in the biodiesel manufacturing process.

Artisan’s thin-film technology is ideally suited to purify biodiesel, which is one of the most common alternative fuels, on the market today. Artisan’s solution is able to purify biodiesel from its chemical by-products downstream of the esterification and/or transesterification reactions. Artisan’s biodiesel purification process eliminates the need for a separate glycerin purification process.

Our biodiesel purification solution produces water-white biodiesel and technical grade glycerin. After removing solvent and water from crude biodiesel, we co–distill methyl ester and glycerin from the salts and heavies.

Solvent Removal and Recovery

In the first process stage, Artisan’s Rototherm® Evaporator is used to remove solvent and water from methyl ester, salts, and glycerin and recovers 99.9% of the solvent for recycle back to the reactor. If necessary, the solvent and water removed can be vapor fed directly to a distillation column to purify and dehydrate the solvent.

Methyl Ester and Glycerin Co–Distillation

In the second step, a Rototherm® is operated at low absolute pressure to vaporize the glycerol and methyl esters, plus any remaining traces of light ends. The vapor exits through a Vapor/Liquid Separator to knock back any entrained liquid and enters a special condenser, using tower water as coolant, where the methyl esters and glycerin condense. The residual solvent and water vapor flow through a direct contact (barometric) condenser to a shared vacuum system. The use of sprays cools recirculates methyl esters to minimize the loss of ME and glycerin to the vacuum system. The condensed methyl esters and glycerin flow downstream to separate the phases and remove any remaining free glycerin from the fuel.