Anaerobic Digestion Could Improve Ethanol's Energy Balance

The Agricultural Utilization Research Institute just finished a study that shows that ethanol plants could displace most of their energy needs through anaerobic digestion of thin stillage.

Anaerobic digestion could boost ethanol plant profits by millions of dollars — and make corn ethanol “greener.”

That’s the finding of a new AURI-sponsored study that showed the feasibility of making methane and fertilizer from thin stillage, dissolved corn solids left over from ethanol production. “Ethanol plants could potentially become energy independent if all the energy in thin stillage could be captured in the form of methane,” says study author David Rein of Rein & Associates, a wastewater engineering company based in Moorhead, Minn.

This would also save ethanol producers money on their energy bills.

Anaerobic digestion could add $10 million to the bottom line of a 50-million-gallon ethanol plant, Rein estimates. Digestion could also conserve water, earn valuable carbon credits, and boost corn ethanol’s energy balance by offsetting fossil-fuel use, he says.

Source : AURI