Grantee Research Project Results
Final Report: A Novel Acoustic Biodiesel Production Process From Animal Fats and Waste Grease
EPA Contract Number: EPD04023Title: A Novel Acoustic Biodiesel Production Process From Animal Fats and Waste Grease
Investigators: Yang, Fangxiao
Small Business: Resodyn Corporation
EPA Contact: Richards, April
Phase: I
Project Period: March 1, 2004 through August 31, 2004
Project Amount: $70,000
RFA: Small Business Innovation Research (SBIR) - Phase I (2004) RFA Text | Recipients Lists
Research Category: Biology/Life Sciences , SBIR - Animal Waste and Waste to Energy , Small Business Innovation Research (SBIR)
Description:
The goal of this research project was to demonstrate the technical feasibility of a noncatalytic process for converting waste grease or triglycerides in general to fatty acid methyl ester (FAME), also known as biodiesel.
Summary/Accomplishments (Outputs/Outcomes):
Resodyn Corporation is working to produce biodiesel with an acoustic biodiesel synthesis reactor (ABSR). The process involves heating the mixture of grease and methanol in the reactor to subcritical points of methanol. The esterification between free fatty acid (FFA) in the grease and the methanol, and the transesterification reaction between triglycerides and the methanol, simultaneously takes place to form FAME, and therefore one-step noncatalytic biodiesel production is achieved. At the supercritical fluid condition (SFC) of methanol, biodiesel can be obtained with a very fast reaction rate. The energy consumption at SFC, however, is too high to make the biodiesel production process economically viable. If reaction conditions are set at a subcritical condition, the energy requirement is significantly lower. The technical obstacle for the reactions at a subcritical condition is that grease and methanol are not miscible and, therefore, agitation is required. The application of acoustic agitation to the process eliminates the use of any rotation parts for the reactor because the process, even though at a subcritical condition, is still at a high methanol pressure.
Various types of waste grease were proposed for testing in the ABSR for biodiesel production. Unfortunately, a flexible hose connecting the pump to the reactor failed (punctured) and methanol vapor escaped and ignited. An explosion occurred, and the tests aimed to use acoustic mixing were modified. The remainder of the tests used Resodyn Corporation’s designed reactor to convert grease at methanol’s supercritical conditions without any agitation (i.e., the reactor was standing still during the experiment).
The products of yellow grease conversion are shown in Figure 1. Under supercritical conditions of methanol, grease is readily converted to biodiesel. The conversion of the grease depends on how much FFA is present in the grease. The higher the fatty acid content, the faster the chemical reaction or the higher the grease conversion to biodiesel.
Figure 1. The products from yellow grease conversion.
Conclusions:
The results demonstrated that the esterification reaction is much faster than the transesterification reaction under supercritical conditions of methanol. This finding is very significant for biodiesel synthesis from waste grease. Because the most current biodiesel synthesis processes cannot handle feedstock with high FFA content, the supercritical fluid process will result in a significant advantage for feedstocks with any fatty acid content. The results have shown that the higher the fatty acid content, the higher the conversion that is obtained with the same residence time (reaction time). The results also show that process pressure is not a critical parameter for biodiesel production as long as the reactor pressure is above the critical point. The reaction temperature, however, is very critical for the completion of grease conversion.
Supplemental Keywords:
acoustic biodiesel production, animal fat, waste grease, free fatty acid, FFA, fatty acid methyl ester, FAME, acoustic biodiesel synthesis reactor, ABSR, methanol, supercritical fluid condition, SFC, EPA, small business, SBIR,, Scientific Discipline, Sustainable Industry/Business, Chemical Engineering, Environmental Chemistry, New/Innovative technologies, waste reduction, waste grease, animal fat, Acoustic Biodiesel Synthesis Reactor, solvent substitute, vegetable oilThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.