Researchers from the University of Alberta claim they have developed a method that accelerates the anaerobic digestion process by up to 70 percent. The key step to speed up the anaerobic degradation process is the addition of conductive materials to the feedstock such as granular activated carbon.
Environmental engineering master’s student Bappi Chowdhury and his colleagues at the University of Alberta found that the added activated carbon in the feedstock functions as a hub for microbes looking to dump or pick up electrons as part of biochemical processes.
The results from the granular activated carbon to the organic feedstock of the anaerobic digester resulted in decomposition times being reduced from 20 to 25 days to just seven. The researchers also tested the degradation rate with the addition of the rock mineral magnetite and found similar, although not as effective, results.
Researchers also experiments with different levels of food waste with fats, oils, and grease (FOG). Based on there testing, they found that a mixture of 70 percent food waste and 30 percent FOG resulted in the fasted anaerobic digestion.
The supervisor of the research, Dr. Bipro Dhar, noted in an interview with Folio, the U of Alberta journal, “More work will first be needed. That means looking for even better and cheaper conductive materials, economic feasibility studies and scaled-up pilot projects.”