New Process Removes Phosphorous From Manure

Portable Manure Phosphorus Exctraction system-MAPHEX. Credit: Hristov Research Group / Penn state


Phosphorous and the Great Lakes

Excessive nutrient input to the Great Lakes has been a primary concern for decades. Lake Erie has been particularly susceptible. Phosphorous inputs in particular are a primary driver in an equation which results in extensive algae growth. Concerted, coordinated action on the part of both Canada and USA resulted in a decline in phosphorous levels in the seventies and eighties.

By the mid-nineties, phosphorous was back, in a big way, and remains the primary factor influencing algae growth. Binationally, huge resources have been devoted to phosphorous reduction and these efforts remain a cornerstone of the Great Lakes Water Quality Agreement between Canada and USA.

Manure Phosphorous Extraction

New work by Penn State University and the U.S. Department of Agriculture points to a new ray of hope on the technological front which is being tested in the largest estuary in American waters, Chesapeake Bay.

Penn State and USDA scientists have patented a new system for the treatment of liquid manure. The Machine is titled MAPHEX for Manure Phosphorous Extraction and involves a three stage process. It is capable of removing 98% of phosphorus and 93% of manure solids from dairy cow manure slurries.

The system is currently designed as a portable two-trailer machine that could be used by multiple small farms; however, it has the potential to be modified to service much larger farms as a permanent installation. The cost of running the system is estimated at $750 per dairy cow per year. One of the major sources of cost is the final filtration system, which uses diatomaceous earth. Alex Hristov, the lead Penn State researcher is looking into making the MAPHEX more cost effective by modifying the filtration stage.

Testing on the Chesapeake

The system will be used in the Chesapeake Bay dairy sector to research its effectiveness and look at logistics for implementation. The Chesapeake area was chosen because 20% of all phosphorous in the Chesapeake watershed was shown to originate from the dairy sector in 2010, therefore it will see significant benefits.

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USDA project summary

Saving the Chesapeake, the largest estuary in USA


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