How successful these filtering systems work in large-scale livestock production remains to be seen, but in the lab they have been nothing short of spectacular.

In one study, Vanotti immersed the membrane into liquid manure that had 1,300 mg of ammonia per liter, and after 9 days, the total ammonia concentration decreased about 50 percent to 663 mg per liter — and as a result, the gaseous ammonia fraction in the liquid linked to ammonia emissions decreased 95 percent from 114.2 to 5.4 mg per liter.

He used the same process in 10 consecutive batches of raw swine manure and ended up recovering concentrated nitrogen in a clear solution that contained 53,000 mg of ammonia per liter.

Obtaining this level of ammonium extraction and nitrogen capture in a research lab is reason enough for farmers and livestock producers to take notice.

However, it’s the real world application that may make a significant improvement on their bottom line. If commercially adapted, this process would reduce the risk for grain farmers by reducing their fertilizer costs and making the supply more reliable.

In a swine operation with 4,000 to 5,000 animals, there would be about 30,000 pounds of nitrogen in the manure being lost in the air each year.

Capturing the N and processing it into a usable form of nitrogen fertilizer would be huge for both the livestock and row crop farmers in the animal rich, but grain poor Southeast.

The nutrient value of poultry litter is slightly different, but perhaps potentially even more important than swine waste in the Southeast, because of the size of the poultry industry across the region.

The potential fertilizer content of poultry manure varies significantly, depending on type of bird raised and content of the feeding ration.

However, the nutrients in this manure could adequately fertilize acres of corn and cotton grown in any of the Southeastern states.

Finding a new source of nitrogen would be big for row crop farmers in the Southeast. For example, a recent Virginia Tech study shows that N accounts for 57 percent ($102 per acre) of the total fertilizer cost of growing 150 bushel per acre corn in the state.

Vanotti says the technology is available and the price of materials for producing his system has actually gone down. Now, it’s up to industry to convert the USDA findings into an affordable and workable system for swine and poultry producers. 

Companies wishing to learn more about the technology and the licensing procedure can contact: Jason Bray, Office of Technology Transfer, USDA, Agricultural Research Service (ARS), Athens, Ga., 30604-5677, phone 706-546-3496 or by e-mail at jason.bray@ars.usda.gov.

rroberson@farmpress.com