Design of a Trap Grease Upgrader for BioFuel Processing - Phase I

EPA Grant Number: SU832486
Title: Design of a Trap Grease Upgrader for BioFuel Processing - Phase I
Investigators: Cernansky, Nicholas P.
Current Investigators: Cernansky, Nicholas P. , Cairncross, Richard A. , Chapman, Jason , Crawford, Douglas , Doan, Thuyvan , Haas, Francis , Letterle, Kenneth , Nguyen, Van-Anh , Powell, Pamela
Institution: Drexel University
EPA Project Officer: Nolt-Helms, Cynthia
Phase: I
Project Period: September 30, 2005 through May 30, 2006
Project Amount: $9,065
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2005) RFA Text |  Recipients Lists
Research Category: P3 Challenge Area - Energy , Pollution Prevention/Sustainable Development , P3 Awards , Sustainability


This project provides capstone senior design experience to several teams of engineering undergraduates at Drexel University through the technical and economic evaluation of a trap grease to biodiesel conversion process. The project incorporates two phases: Phase I characterizes thermogravimetric and trace contaminant properties of crude trap grease and Phase II involves the construction of a pilot-scale trap grease upgrading process based on the results of Phase I. The Phase II pilot-plant will produce feedstock for an industry partner's pilot biodiesel plant.


Sustainable benefits of substituting biodiesel for petroleum diesel include reduced air pollution, carbon-neutral emissions, and diminished dependence on foreign oil. The most common feedstock for biodiesel production is virgin soybean oil; however, the cost and geographic distribution of soy feedstock has confined the production of biodiesel to primarily Mid-Western and Great Plains States.

Waste cooking oils are another feedstock for biodiesel production, but these are used locally as additives for animal feed. Trap grease has no secondary market and is therefore a true waste product. Due to the disposal fee structure for trap grease, a significant amount of it goes uncollected. Grease then enters the water system resulting in a financially and environmentally costly pollution problem.

We propose to use waste cooking grease captured from grease traps as a feedstock to produce biodiesel. This provides the combined benefits of generating biodiesel feedstock in soy-scarce areas, decreasing grease loading to publicly operated treatment works, and creating an incentive for restaurants to comply with municipal grease disposal regulations.


Trap grease is distinctly different from so called yellow greases (waste cooking oil) and neat vegetable oils. Virtually any substance that enters the drain of a restaurant sink may be included in the trap grease, including putrescible solids and water.

Phase I seeks to characterize the properties of trap grease to provide design data for Phase II plant design. Arrangements have been made with Gloucester County Utilities Authority wastewater treatment plant in West Deptford, NJ to allow undergraduate engineering students to capture samples of trap grease that have been collected from local dining locations and conveyed to the plant for disposal. Crude grease will be separated into grease, water, and solids phases by thermal and gravimetric methods. Separate grease and water phases will be forwarded to the USDA Eastern Regional Research Center for more detailed analysis of lipid, free fatty acid, and trace contaminant content.

Expected Results:

Phase I will yield publishable data on the crude and trace composition of trap grease, which currently does not exist in the literature. Drexel students will benefit from real-world design experience and their interactions with industry and governmental agencies. Phase II will produce a pilot plant suitable for demonstrations to other municipalities interested in converting trap grease to biofuels.

Publications and Presentations:

Publications have been submitted on this project: View all 3 publications for this project

Supplemental Keywords:

effluent, discharge, pollution prevention, alternatives, sustainable development, innovative technology, renewable, waste reduction, waste minimization, treatment, POTW, public policy, public good, engineering, Pennsylvania, PA, EPA Region 3,, RFA, Scientific Discipline, INTERNATIONAL COOPERATION, TREATMENT/CONTROL, Sustainable Industry/Business, POLLUTION PREVENTION, cleaner production/pollution prevention, Environmental Chemistry, Sustainable Environment, Energy, Technology, Technology for Sustainable Environment, Chemicals Management, Environmental Engineering, waste to fuel conversion, energy conservation, waste cooking oils, alternative to petroleum diesel fuel, renewable fuel production, emission controls, biotechnology, energy efficiency, engineering, alternative fuel, biodiesel fuel, alternative energy source, environmentally benign alternative, biofuel, green chemistry, renewable energy

Progress and Final Reports:

  • Final Report