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ARS Home » Northeast Area » University Park, Pennsylvania » Pasture Systems & Watershed Management Research » Research » Publications at this Location » Publication #370448
Research Project: Sustainable Intensification of Crop and Integrated Crop-Livestock Systems at Multiple Scales

Location: Pasture Systems & Watershed Management Research

Title: Evaluations of benefits and impacts of nutrients recovery techniques for dairy manure

Author
item JOLLIET, OLIVIER - University Of Michigan
item HUANG, LEI - University Of Michigan
item WALLACE, JIM - Consultant
item Rotz, Clarence - Al
item WANG, YING - Dairy Management, Inc

Submitted to: Environmental Toxicology and Chemistry
Publication Type: Proceedings
Publication Acceptance Date: 11/28/2019
Publication Date: 5/3/2020
Citation: Jolliet, O., Huang, L., Wallace, J., Rotz, C.A., Wang, Y. 2020. Evaluations of benefits and impacts of nutrients recovery techniques for dairy manure. Environmental Toxicology and Chemistry. P. 300.

Interpretive Summary: No Interpretive Summary is required for this proceeding. JLB.

Technical Abstract: Opportunities exist to improve nutrient use efficiency and nutrient cycling in dairy food supply chains, particularly by closing the loop between livestock production (animal manure), food waste (losses in production, retail, and consumption) and crop production (fertilizer losses). In response to these different needs and opportunities, this study aims to assess the life cycle environmental performances of four innovative manure nutrient recovery techniques. We ensure consistency between nutrient mass balance, inventory flows at the farm level, and we analyze trade-offs between reduction in emissions and increased energy consumption during nutrient recovery. The selected promising manure nutrient recovery techniques include a) centrifuge, b) dissolved air flotation (DAF), c) ultrafiltration, and d) evaporation technologies. We first used a mass-balance approach to analyze the respective performances of the nutrient recovery techniques in terms of N, P and K nutrients as well as total and solid masses. In parallel, data for energy and chemical consumption of each system were collected. P adsorbed to solids and the DAF technology enables recovery of close to 80% of manure P and 60% of organic N in dry solids, while all ammonia and some of the remaining organic N are in the diluted effluent. Evaporation techniques enhance these performances further by recovering more than 90% of manure P, 85% of organic-N in dry solids, and 84% of NH4-N as concentrated aqua ammonia, with the residual water rejected as clean water. Since these nutrient recovery systems affect other farm emissions (barn and field emissions during manure and fertilizer applications), the data from each nutrient technique were then integrated using the Integrated Farm System Model (IFSM) to derive consistent life cycle inventory flows (e.g. ammonia and nitrate emission) associated with each system and to determine related nitrogen, phosphorus and carbon footprints and efficiencies. Finally, trade-offs between energy and chemical consumption related impacts and reduction in nutrient recovery impacts were analyzed by applying the ImpactWorld+ LCIA method, ensuring a high consistency between LCI and LCIA approaches. This study shows the potential interest of nutrient recovery techniques in terms of reduced nutrient related emissions and N and P footprints. It is however crucial to take advantage of non-renewable electricity and heat production systems to ensure that the energy consumption and related impact are lower than that of mineral fertilizer production