2007 Annual Report
1a.Objectives (from AD-416)
Develop and evaluate environmentally superior technologies to prevent off-farm release of nutrients and to reduce pathogens, odors, and ammonia emissions. Develop information and technologies to enhance or retrofit existing manure treatment systems to help producers meet environmental criteria (nutrients, emissions, and pathogens). Improve and refine constructed natural treatment technologies to effectively manage nutrients including reducing emissions of ammonia and nitrous oxide. Develop and evaluate new and improved technologies that concentrate/sequester nutrients from manures or create value added products including conversion of livestock waste to energy. Evaluate swine wastewater treatment systems that can be used to reduce emissions, manage nutrients, and control pathogens on small farms. Develop cooperative activities as needed to conduct the research.
1b.Approach (from AD-416)
This research will take a synergistic approach towards developing more effective animal waste treatment practices and holistic systems to solve these problems. Four complementary approaches will be pursued. First, environmentally superior technologies and combination of technologies will be developed and evaluated to prevent off-farm release of nutrients and to reduce pathogens, odors, and ammonia emissions. These technologies include improved solid-liquid separation, phosphorus extraction, enhanced biological nitrogen treatment, anaerobic ammonia oxidation, litter wash, material science and green oxidant application development, and their integration into systems of treatment technologies. Second, investigations will be conducted to further our limited knowledge on biology of anaerobic lagoons and develop technologies that can be used to retrofit existing manure treatment systems. To accomplish this, we will use state-of-the-art tools such as non-invasive estimation of oxygen absorption, enzyme activities, emission quantification with open-path laser ammonia detector, and we will develop an improved bio-filtration method to clean barn air. Third, research will be conducted to enhance constructed natural treatment technologies such as constructed wetlands, floating wetlands and riparian zones to more effectively manage nutrients using passive systems. Fourth, we will develop guidelines, protocols and standards for the beneficial use of manure by-products. These include improved methods to recycle and recover nutrients from anaerobic lagoon sludge and to produce hydrogen from livestock manure. Results from this project will advance the state of science for more effective animal waste treatment and implementation of environmentally-safe alternatives to traditional land application. Systems of treatment technologies that capture nutrients, reduce emissions, and kill pathogens need to be developed and evaluated. Small farms will require systems that meet environmental regulations and have a reasonable initial cost.
Lower Cost, Second Generation System Meets High Standards of an Environmentally Superior Technology: New legislation in North Carolina promotes the replacement of old lagoon technology with new Environmentally Superior Technology. Scientists at ARS Florence and industry cooperators completed design and demonstration of a second generation treatment system for swine waste that can achieve high treatment performance of an Environmentally Superior Technology, yet it is much more economical than earlier versions. The system combines solid-liquid separation, biological ammonia treatment, and phosphorus removal and produces a deodorized and disinfected liquid effluent. The second generation system was installed full-scale in a 5,150-head finishing swine operation and demonstrated for half a year under steady-state conditions. The treatment system removed 97.7% of the total suspended solids, 99.6% of biological oxygen demand, 96.1% of total nitrogen, 97.3% of ammonia, 94.0% of total phosphorus, 99.3% of copper, 99.2% of zinc, 99.9% of odor compounds, and 99.99% of pathogen indicators. Ammonia concentration in air of the barns was reduced, and that enhanced animal health and productivity: mortality decreased 57%, daily weight gain increased 11%, and feed conversion improved 5.4% compared to the traditional lagoon management. These results overall show that cleaner alternative technologies can have significant positive impacts on livestock production and the environment. This research contributes to the goals of Problem Area 2, 'Innovative Technology for Collection, Storage, and Treatment,' under the Nutrient Management Component of National Program 206.
Manure Treatment System Erases Greenhouse Gases: Less greenhouse gas—and more carbon credits per pig—are the latest environment-friendly benefits being credited to an innovative hog waste-management system invented by Agricultural Research Service scientists at Florence, SC. The ARS researchers found that replacing conventional anaerobic lagoon practices with the new aerobic waste management system reduced greenhouse gas emissions by 97 percent. It cut annual emissions from 4,972 tons of carbon dioxide (CO2) equivalents to just 153 tons. This indicates the system may have a role in the fledgling CO2 trading market, which allows farmers to earn money based on how much carbon dioxide and other greenhouse gases they can prevent from entering the atmosphere using alternative technologies. The earned carbon credits can help alleviate installation costs associated with cleaner aerobic systems and facilitate producer adoption of environmentally superior technologies to replace current anaerobic lagoons in the USA. This research contributes to the goals of Problem Area 2, 'Innovative Technology for Collection, Storage, and Treatment' under the Nutrient Management Component of National Program 206.
Wastewater Treatment System with Simultaneous Separation of Phosphorus and Manure Solids: Scientists at ARS Florence invented a new wastewater treatment system and processes for removal of solids, pathogens, nitrogen, and phosphorus from municipal and agricultural wastewater that include the simultaneous separation of solids and phosphorus from wastewater and industrial effluents. A U.S. Patent Application (S.N. 11/820,396) was filed June 19, 2007. The system has been successfully demonstrated full-scale in a swine farm in North Carolina. The combined separation process is more efficient in terms of equipment needs and chemical use. Thus, it reduces installation and operational cost of manure treatment, which will greatly help with adoption of the new treatment technology by swine producers. This research contributes to the goals of Problem Area 2, 'Innovative Technology for Collection, Storage, and Treatment,' under the Nutrient Management Component of National Program 206.
Greenhouse Emissions from Riparian Buffers: Riparian buffers are used throughout the world for the protection of water bodies from nonpoint source pollution, particularly nitrogen. Yet, this water quality protection has the potential of causing air quality degradation from the production of nitrous oxide. We discovered that soil C/N ratios (>25) reduced the potential for nitrous oxide production. We initiated photoacoustic measurements of the actual nitrous oxide emission vs. soil carbon/nitrogen (C/N) ratios to determine if the soil C/N was an easily measured and widely applicable parameter for identification of hot spots of actual nitrous oxide emissions from riparian buffers. Initial results suggest that the actual emissions may be lower than the potential nitrous oxide production. This research contributes to the goals Problem Area 1, 'Understanding the Biological, Chemical, and Physical Mechanisms Affecting Emissions,' and Problem Area 3, 'Control Technologies and Strategies for Emissions,' under the Atmospheric Emissions Component of National Program 206.
Improved Process Model for Ammonia Emission from Treatment Lagoons Under Varying Wind Speeds and Gas Bubbling: Existing mathematical models are severely limited in accuracy for predicting ammonia volatilization from livestock treatment lagoons. We improved process modeling performance by adding two original components:.
1)transport of ammonia by lagoon gas bubbles and.
2)variable wind speed impact on the ammonia volatilization. We validated our new model by predicting seasonal ammonia emissions from three different swine lagoons receiving flushed manure (traditional lagoon), solid-separated manure (partially-treated lagoon), and fully-treated manure (treated lagoon). Our model accurately predicted the measured ammonia emissions from the three lagoons with distinctively different water quality characteristics. Had either bubbling-enhanced mass transport or variable wind not been taken into account in the model, the ammonia emissions from the three swine lagoons would have been significantly under-predicted. The new model provides not only more accurate predictions of ammonia emission, but also a convenient way of predicting ammonia emission from swine lagoons using easily obtainable data. This research contributes to the goals of Problem Area 1, 'Understanding the Biological, Chemical, and Physical Mechanisms Affecting Emissions,' and Problem Area 2, 'Innovative Technology for Collection, Storage, and Treatment,' under the Atmospheric Emisions Component and Nutrient Management Component, respectively, of National Program 206.
Destruction of Hormones Using a Green Oxidant: Hormones in wastewater effluent are an emerging problem for both agriculture and municipalities. We investigated the possibility of destroying these hormones with new green catalyst TAML Activators. TAML is short for iron tetra-amido macrocyclic ligand. The TAML activators were invented by a Carnegie Mellon University scientist. We have evaluated their usefulness under a Materials Transfer Agreement. The research has been conducted collaborative with the ARS in Fargo, North Dakota. The TAML activators were very effective in rapidly destroying all forms of estrogen. There were no deleterious intermediates or byproducts. Initial results suggest the destruction will also be effective in actual wastewater. This research contributes to the goals of Problem Area 4, 'Holistic Treatment Technologies for Nutrients, Pathogens and PACs' under the Pathogens and Pharmaceutically Active Compounds (PACs) Component of National Program 206.
Abatement of Ammonia Emissions from Swine Lagoons Using Solid-Liquid Separation:
Substantial abatement of ammonia emissions can be obtained when swine lagoons are retrofitted with a high-rate solid-liquid separation technology. Annual ammonia emissions were reduced in a lagoon with prior solid-liquid separation by 70% with respect to those of the traditional anaerobic lagoon. These results demonstrate that solid-liquid separation technologies can substantially reduce ammonia emissions from swine production operations. This research contributes to the goals of Problem Area 2, 'Innovative Technology for Collection, Storage and Treatment' and Problem Area 3, 'Control Technologies and Strategies for Emissions,' under the Nutrient Management Component and Atmospheric Emissions Component, respectively, of National Program 206.
Bacteria Propel Gains in Ammonia Removal: Using an innovative bacterial process, ARS scientists are paving the way for new, cost-efficient and large-scale methods of removing ammonia from livestock wastewater. In tests with anammox -- a technology that uses rare anaerobic bacteria to convert nitrite and ammonium to harmless dinitrogen gas -- the scientists have scored noteworthy results. They are the first researchers to isolate from animal wastewater the planctomycetes bacteria used in the anammox process. They have also highlighted anammox's commercial potential by removing nitrogen from wastewater at rates higher than those achieved with conventional methods and lower cost. This finding can be of significant importance to farming systems because excess ammonia in modern, industrial-type livestock production is a global problem, and the use of conventional biological nitrogen removal methods is usually hindered by operational cost, which can be lowered four-fold with the anammox process. This research contributes to the goals of Problem Area 2, 'Innovative Technology for Collection, Storage, and Treatment,' under the Nutrient Management Component of National Program 206.
Denitrification Enzyme Activity in Swine Lagoons: Establishing the mechanisms of nitrogen cycling in livestock wastewater lagoons is important both to understanding current practices and to advancing treatment technology. Recent publications of high levels of di-nitrogen emissions and high levels of potential surficial oxygen transfer indicated that large amounts of nitrogen may be removed via denitrification in anaerobic lagoons. If this denitrification is occurring via classical denitrification, the denitrification enzyme levels should be correspondingly high. We measured denitrification enzyme activity (DEA) in eight lagoons with varying loads of swine wastewater. A university research lagoon had moderately high levels of DEA. However, the commercial lagoons had surprisingly low DEA. These results suggest that di-nitrogen may be produced at different levels and by different mechanisms in different lagoons. This research contributes to the goals of Problem Area 1, 'Understanding the Biological, Chemical, and Physical Mechanisms Affecting Emissions,' and Problem Area 2, 'Innovative Technology for Collection, Storage, and Treatment,' under the Atmospheric Emissions Component and Nutrient Management Component, respectively, of National Program 206.
Wet Gasification of Animal and Municipal Wastes for Energy Generation and Waste Treatment: We investigated the applicability of the new wet gasification technology to treat and harness energy from animal and municipal wastes. Based on theoretical considerations and limited experiments with dairy manure wet gasification, we project that wet wastes such as swine manure and sewage sludge could be fed directly into a wet-gasifier. They would produce more energy than combusting the same amount of brown coal. The costs of a conceptual first generation wet gasification manure management system for a model swine farm were significantly higher than that of traditional anaerobic lagoon systems. However, there are many significant environmental advantages of the wet gasification:.
1)removing oxygen demanding wastes, estrogens, and odorous compounds;.
2)achieving total pathogen kills;.
3)recovering most of nitrogen as ammonia, which could be used as a fertilizer; and.
4)producing relatively clean water which, after minimal treatment, could be used as a livestock drinking water. This research contributes to the goals of Problem Area 3, 'Byproduct Utilization Technologies,' under the Byproducts Component of National Program 206.
Recovery and Reuse of Phosphorus Materials: Recycling and reuse of phosphorus (P) is becoming important for both the fertilizer industry and farmers because world phosphorus reserves are limited. Phosphorus materials were recovered from the full-scale wastewater treatment plant using the NC approved Environmentally Superior Technology (EST). Leaching soil column studies with and without cotton plants showed that P availability was similar when soil was fertilized with commercial triple superphosphate (TSP), broiler litter, or recovered P material. Movement of soil P below the depth where fertilizer materials were placed (15-cm depth) occurred only for soil columns with TSP treatment. Results suggest the recovered P from swine wastewater can be useful as a readily available P fertilizer for cotton but less prone to leaching than commercial TSP. This research contributes to the goals of Problem Area 3, 'Byproduct Utilization Technologies,' under the Byproducts Component of National Program 206.
5.Significant Activities that Support Special Target Populations
USDA-ARS Florence scientist made invited seminar presentations at the College of Sciences, University of Texas at San Antonio (UTSA) - a designated Hispanic Institution. The overall purpose of the presentations was to inform faculty and students of ARS' primary role as the principal research agency of the U.S. Department of Agriculture. Faculty and students that attended the presentations received information on the following topics: description of ARS mission and organization; employment opportunities in ARS; and summary of scientific activities at ARS Florence.
Research continues on two Specific Cooperative Agreements with North Carolina A&T State University. Additionally, several students interacted with customers/stakeholders at an ARS Customer Workshop held in Florence, South Carolina.
|Number of new CRADAs and MTAs||1|
|Number of active CRADAs and MTAs||1|
|Number of patent applications filed||1|
|Number of web sites managed||1|
|Number of non-peer reviewed presentations and proceedings||21|
|Number of newspaper articles and other presentations for non-science audiences||12|
Ro, K.S., Hunt, P.G. 2006. A new unified equation for wind-driven surficial oxygen transfer into stationary water bodies. Transactions of the American Society of Agricultural and Biological Engineers. 49(5):1615-1622.
Loughrin, J.H., Szogi, A.A., Vanotti, M.B. 2006. Reduction of malodorous compounds from liquid swine manure by a multi-staged treatment system. Applied Engineering in Agriculture. 22(6):867-873
Ro, K.S., Hunt, P.G. 2007. Characteristic wind speed distributions and reliability of the logarithmic wind profile. Journal of Environmental Engineering. 133(3):313-318.
Ro, K.S., Hunt, P.G., Poach, M.E. 2006. Wind-driven surficial oxygen transfer and dinitrogen gas emission from treatment lagoons. Journal of Environmental Science and Health. 41:1627-1638.
Poach, M.E., Hunt, P.G., Reddy, G.B., Stone, K.C., Johnson, M.H., Grubbs, A. 2007. Effect of intermittent drainage on swine wastewater treatment by marsh-pond-marsh constructed wetlands. Ecological Engineering 30:43-50.
Shappell, N.W., Billey, L.O., Forbes, D., Poach, M.E., Matheny, T.A., Reddy, G.B., Hunt, P.G. 2007. Estrogenic activity and steroid hormones in swine wastewater processed through a lagoon constructed-wetland system.. Environmental Science and Technology 41(2):444-450.
Vanotti, M.B., Szogi, A.A., Hunt, P.G., Millner, P.D., Humenik, F.J. 2007. Development of environmentally superior treatment system to replace anaerobic swine lagoons in the usa. Bioresource Technology 98:3184-3194.