Animal Manure Anaerobic Digesters Continue to Work Out the Kinks

Bay Journal article (2019-02-06) examined the ongoing struggles to use anaerobic digestion technology in the disposal of animal and poultry manure on Maryland’s farms. Despite millions of dollars of State investment, no project has yet proven profitable or sustainable. However, even the failed projects provide important lessons as anaerobic digestion slowly moves to the United States.

Anaerobic digestion is a process where microorganisms break down biodegradable material, such as animal waste or sewage sludge, without oxygen. Subjecting poultry waste to the process produces a nutrient-rich fertilizer and biogas that can be used for energy or fuel. The technology is heavily used in some European countries. The article states that Germany alone has over 10,000 working system. In comparison, the United States has fewer than 300.

According to the article, the state spent nearly $6 million on eight projects through the Maryland Department of Agriculture’s (MDA’s) Animal Waste Technology Fund. Some projects, such as a digester for a poultry farm in Dorchester County, will likely be canceled after frequent equipment breakdowns, the lack of parts domestically, and the need for metric tools to service the equipment. Other projects, like a horse rescue farm in Howard County or a dairy farm in Frederick County, are not expected to recoup their costs until well-into or near the end of the digesters’ projected lifespans. A poultry waste converter on a farm near Pocomoke City, has gradually ramped up production since it started operation in 2017 but is projected to lose $123,000 per year according to the University of Maryland Environmental Finance Center.

From the article:

When asked which of the projects ranks as the most promising, the MDA official who until recently oversaw the fund replied: “Unfortunately, I don’t think I would point to any particular one.” …

Stephanie Lansing, a University of Maryland agriculture researcher, has studied some of the funded projects and come to a timeless conclusion: “Being an early adopter is very challenging and expensive,” she said. …

Many of the Maryland projects show that what works in a laboratory doesn’t necessarily work out in the field, said Jarrod Miller, who worked with Eastern Shore farmers for years as a University of Maryland extension agent based in Princess Anne County.

“We did need to run some of this stuff to find out,” said Miller, who is now with the University of Delaware. “A lot of people will learn from us.”

The article also described the need to dispose of poultry litter other than spreading it on Eastern Shore farmland that may already be saturated with phosphorus. Excess phosphorus cannot bind with overly saturated soils and instead runs into the Chesapeake Bay and its tributaries and degrades water quality.

Useful Links

MDA Animal Waste Technology Grants Webpage