Researchers from the U.S. Department of Agriculture (USDA) Agricultural Research Service Southeast Area (ARS SEA) have developed a new way to recover nitrogen from livestock wastes, which has been commercialized by Renewable Nutrients.
Conservation and recovery of nitrogen from livestock, industrial and municipal wastes is important for economic and environmental reasons. In the United States, the largest source of ammonia emissions — and the distinctive odor they generate — is livestock farming.
The nitrogen components of ammonia are useful as a fertilizer, but many areas in the U.S. produce more manure-generated nutrients than the available cropland can assimilate. Therefore, the removal and recovery of ammonia is desirable when treating livestock waste because the nutrients can be exported off the farm. This could solve the problems of nitrogen surpluses in concentrated livestock production, provide a substitute for commercial fertilizers and create new businesses.
The new technology recovers ammonia-nitrogen from wastes using gas-permeable membranes. The process involves passing ammonia through microporous hydrophobic membranes and concentrating it in a clear solution. The process can be used for removing and recovering nitrogen from two types of livestock waste: liquid manures in storage tanks and the air of poultry and animal barns. It can recover 98% of the nitrogen.
Therefore, the removal and recovery of ammonia is desirable when treating livestock waste because the nutrients can be exported off the farm.
Renewable Nutrients, a small business with experience recovering phosphorus from wastes, was the recipient of the ammonia-trapping technology through two exclusive licenses granted by the USDA. A Cooperative Research and Development Agreement (CRADA) facilitated testing of a company-developed pilot unit to determine its suitability for municipal wastes and helped identify the best membrane material composition for commercial units. The technology is commercialized as Quick Wash® Nitrogen Removal & Ammonia Recovery.
Other technology transfer mechanisms and activities included:
In 2021, the technology was selected for expanded delivery by the Agriculture Innovation Agenda (AIA), a new initiative to facilitate goals of increasing U.S. agricultural production by 40% while reducing the environmental footprint of agriculture by 50% by 2050. Implementing the new technology in municipal plants could have global positive impacts, increasing nitrogen recycling and reducing greenhouse gas emissions.
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