Performing Department
(N/A)
Non Technical Summary
Livestock manure streams constitute a primary source of nutrients leading to watershed eutrophication, and nutrient mitigation is a major problem for the agricultural industry. Many dairies have anaerobic digesters (ADs) that reduce manure volumes and generate methane for energy. But the nutrients remaining in the wastewater are emitted to the environment after release from ADs. Midwestern BioAg (MBA), a producer and marketer of specialty fertilizers, has implemented a new facility to capture these nutrients and convert them to fertilizer. For our customers who farm organically, manure is an important nutrient source. Making an organic version of our new fertilizer could generate an important source of fertilizer, but we cannot make the current fertilizer organic because of a single synthetic component present in the process. This funding is to develop a new process, based on technology licensed from the USDA-ARS, which will use agricultural residues to create an organic version of the AD-derived fertilizer. Development of this organic fertilizer will provide many benefits. Cleaner water, reduced greenhouse gases, and fewer non-renewable resources used, as nutrients are removed from AD wastewater and recycled for crop production. A new source of organic fertilizer will support organic agriculture while providing an economic incentive for dairies to reduce air and water pollution. And construction of manufacturing facilities will bring good jobs to rural areas. MBA has the sales and marketing expertise, and distribution networks, to sell this fertilizer to organic farms across the Midwest and beyond, permitting rapid commercialization of the technology.?
Animal Health Component
75%
Research Effort Categories
Basic
20%
Applied
75%
Developmental
5%
Goals / Objectives
?Identify Candidate Flocculants. Identify and obtain a variety of flocculant preparations that are either 1) potentially obtainable at industrial scale as organic, according to National Organic Program standards, or 2) potentially biodegradable by the microbes present in AD effluent, or 3) meeting both of these qualifications. Locations: MBA, USDA, Aqua Engineering.Perform preliminary Flocculant Testing. Using standard flocculation assays in the USDA-ARS and MBA laboratories, test the flocculation properties of the various preparations using AD effluent obtained from the Fair Oaks Digester. Determine the mass of solids obtained and nutrient content of the solids "cake" using MBA's standard assays. Locations: MBA, USDA.Perform Flocculant testing in DAF Tank Models. Select flocculant preparations that are sufficiently promising and supply them to the Aqua Engineering and ALPRO. Initiate tests of flocculation performance vs. our current polymer in laboratory-scale DAF tanks that model the Fair Oaks facility. Location: Aqua Engineering and ALPRO labs.Perform Initial Biodegradability Assessment. Implement assays for biodegradability of promising polymers. These are likely to be a combination of microbiological methods (for example, use of polymers as a sole carbon source) and chemical methods (reduction in polymer molecular weight, release of CO2). Location: MBA with University of Wisconsin consultation.
Project Methods
This project is primarily a scientific endeavor focused on identifying a pathway to produce an organically listable fertilizer product which incorporates the byproducts produced by anaerobic digestion of animal waste off of a large dairy. We have identified two strategies to our goal of an organically listable product: (1) identify an organically listed, or listable, flocculant to replace the current one in use and (2) demonstrate that the polymer is digested by microbes and thus seek NOP approval via this route.Identification of a polymer that meets NOP standards will be done through our collaboration with Drs. Piazza and Garcia of the USDA, and through evaluation and identification of potential natural polymers for testing. Our USDA collaborators have identified hemoglobin-based polymers that are likely to be able to meet NOP guidelines or organic components. We will also be evaluating a number of natural and minimally-modified polymers that might meet NOP standards while also providing strong performance as flocculating agents in our DAF Tank-based water purification system. We will collect data on total flocculant production, nutrient content of floc, nutrient content of wastewater, and optimal flocculant levels for optimal performance. The work will be performed in laboratory models of the full-scale nutrient recovery process used at Fair Oaks, IN. Nutrient analyses will be performed in licensed laboratories that routinely test for nutrient content in fertilizers, manures, and other agricultural inputs. Candidate polymers will be advanced based on overall performance in our laboratory test systems.Identification of biodegradable polymers will be performed used candidate polymers as sole carbon sources in enrichment cultures inoculated with effluent from the anaerobic digesters at Fair Oaks. We will use both aerobic and anaerobic cultures to culture organisms capable of degrading the candidate polymers. Polymers that are advanced to Phase II will both perform well in the DAF Tank model system, and be degradable in our enrichment cultures. Priority will be given to polymers with the best combination of 1) Performance in DAF Tank models, 2) Degradability in enrichment cultures, and 3) Shorter half-life of degradation. We can imagine two primary ways in which we optimize degradability. First, the polymer is rapidly degraded by the totality of microorganisms in the cake produced after flocculation, and second, the polymer is rapidly degraded by a subset of these microorganisms, and we must seed the cake with these organisms to achieve and acceptable half-life for the polymer. The specific direction we take will depend on how the various polymers perform.Finally, although a broad education campaign is not anticipated in Phase I, we will certainly be working closely with consultants and NOP-evaluators to educate them on our processes, obtain feedback on the likelihood of NOP-compliance, and plot a path to NOP compliance. We will also be working with various environmental groups to help them understand the importance of this technology to providing clean water around dairies, and of recycling nutrients into the agricultural system.Specific evaluation studies include:Determination of nutrient recovery efficiency by various polymers in DAF Tank models. Nutrient analysis will be done through contract laboratories using cake generated in our laboratories.Determination of total cake produced by candidate polymersEstimation of polymer half-life in preliminary degradation studies. This will be determined through growth curves of microbial cultures, and potentially through NMR or mass-spec analysis of metabolites.Evaluation of the chemical structures of the best-performing polymers and use of this information to identify additional polymers that may perform well as flocculants.