Feasibility Analysis of Steam Reforming of Biodiesel by-Product Glycerol to Make Hydrogen

Abstract

Glycerol is a major byproduct during the production of biodiesel and it consists high impurities such as methanol, water, fatty matter, and ash. In general, for every 100 pounds of biodiesel produced via transesterfication, approximately 10 pounds of crude glycerol are produced as a by-product. As the biodiesel industry is rapidly expanding in the United States, market is being flooded with a glut of crude glycerol. Due to its high impurities, it is expensive to purify and use in food, pharmaceutical, or cosmetics industries. Hence, finding the valuable alternative to use glycerol which is economically and environmentally friendly would be important for the success of the biodiesel industries.

The research on feasibility analysis of steam reforming of biodiesel by-product is conducted at the Chemical Engineering Department, Texas A&M University under the faculty advisor, Dr. Mahamoud M. El-Halwagi. The process design involves steam reformer where biodiesel waste is heated in presence of catalyst and steam at 850oC to produce hydrogen, carbon-dioxide, and carbon monoxide. Carbon monoxide is further subjected to water gas shift (WGS) reaction to form hydrogen and carbon dioxide. The product stream consists of 71.7% of hydrogen and 28.5% of carbon dioxide.

Hydrogen produced from the steam reforming process includes small quantities of carbon monoxide, carbon dioxide, water and methane as impurities. Depending upon its use, it requires further purification.

Simulation was done on Aspen Plus. Future work of this research involves process integration and cost analysis of the process and expected to complete by May 2009.