Biodiesel Crude Glycerin Fraction Separations with an Emphasis on Methanol Recovery

Abstract

The University of Arizona Biodiesel Pilot Plant aims to convert waste cooking oil from restaurants located at the university’s student unions into biodiesel to fuel campus vehicles. With the help of the project’s community industrial partner, Grecycle, students from a variety of majors have constructed a 100-gallon single reactor plant and quality-testing laboratory. The waste cooking oil is collected from student unions, filtered, and deposited at the plant. From there, students use chemical processes to convert the waste oil into biodiesel meeting the American Society for Testing and Material’s quality standards. Our project intends to optimize the separations of the liquid byproduct stream by more efficiently recovering methanol for recycling, as well as separating water and glycerin, thus creating higher purity, more valuable products. Both Aspen and ChemCAD will be utilized to simulate a divided wall column separations method for this process at the pilot scale, and a full process design will be provided as a template for future pilot and large scale biodiesel operations.