The McLanahan Nutrient Separation System can also extract nutrients from the water to serve as fertilizer and help solve the ever-present agricultural problem of manure management.
The system uses an anaerobic digester, which takes waste, such as manure, and produces energy as a byproduct – and couples it with an ultrafiltration, air stripping and a reverse osmosis system.
It produces water clean enough for livestock to drink or to dispose of in an environmentally friendly manner.
“If you have 1,000 cows on your operation, they produce about 10 million gallons of manure a year,” said Steve Safferman, an associate professor of biosystems and agricultural engineering who is involved in the project. “About 90% of the manure is water but it contains large amounts of nutrients, carbon and pathogens that can have an environmental impact if not properly managed.
“Here in Michigan we have a tendency to take water for granted,” he added. “But out west, for example, where drought remains an issue, the accessibility of clean water could make the difference between a farm remaining viable or going out of business.”
The process extracts the nutrients from the manure that can be harmful to the environment and can be re-used as fertilizer. It does this by capturing a large percentage of the ammonia that would otherwise be lost in the atmosphere.
Currently the system produces about 50 gallons of water from 100 gallons of manure. The team’s goal is to increase that number to about 65 gallons. It’s hoped that the McLanahan Nutrient Separation System will be ready for commercialization by the end of this year.