Hybrid System

The hybrid system is project funded by a USDA Conservation Innovation Grant to investigate the integration of biodiesel and biogas technologies in a “Hybrid Bio-Refinery” concept to leverage economic and energy synergies between the two biofuel production processes. The exchange of byproducts between the biodiesel and biogas production will enhance the overall efficiency of each process, increasing the overall net amount of bio-energy from a given amount of feedstock material.

Glycerin, a byproduct from making biodiesel has previously been shown to enhance methane production in an anaerobic digester.  In this project we will test various levels of glycerin and measure the amount of methane production.

In the end, we hope to develop a model where a farm could evaluate how much biodiesel they wanted to produce, what volume of manure will be in the digester, what amount of glycerin to add and get an estimate of the output and economics of the system.

Overview of a hybrid biogas/biodiesel system.
Figure 1. Overview of a hybrid biogas/biodiesel system.