1a. Objectives (from AD-416):
1. Develop improved treatment technologies to better manage manure from swine, poultry and dairy operations to reduce releases to the environment of odors, pathogens, ammonia, and greenhouse gases as well as to maximize nutrient recovery. 2. Develop renewable energy via thermochemical technologies and practices for improved conversion of manure into heat, power, biofuels, and biochars. 3. Develop guidelines to minimize nitrous oxide emissions from poultry and swine manure-impacted riparian buffers and treatment wetlands. 4. Develop beneficial uses of manure treatment technology byproducts.
1b. Approach (from AD-416):
This research will take a synergistic approach towards developing innovative and effective animal manure treatment practices and holistic systems. This research will pursue four complementary bioresource management approaches. First, improved treatment technologies to better manage manure from swine, poultry, and dairy operations will be developed to reduce releases into the environment of odors, pathogens, ammonia, and greenhouse gases as well as to maximize nutrient recovery. These technologies include improved solid liquid separation, enhanced biological nitrogen treatment by anaerobic ammonia oxidation, recovery of ammonia from manure using gas permeable membranes, recovery of phosphorus from solid manure, wastewater treatment using constructed wetlands, in-house composting of poultry litter, and their integration into systems of treatment technologies. Second, investigations will be conducted to develop thermochemical technologies and practices for improved conversion of manure into heat, power, biofuels, and biochars. Manure based feedstocks for thermochemical conversion will be evaluated. Improved methods to condition manures for biochar and combustible gas production using pyrolysis will be determined. An efficient carbonization process for production of manure biochars with specific composition and properties for beneficial use will be developed. Third, research will be conducted to develop guidelines to more effectively manage and minimize nitrous oxide emissions from poultry and swine manure impacted riparian buffer zones and treatment wetlands. Fourth, we will develop beneficial uses for manure byproducts. These include the use of manure biochars as adsorbants for gaseous and aqueous contaminants, as soil amendments to improve physical and chemical properties, and as fertilizer source for crop production. Results from this project will advance the state of the science for more effective animal waste treatment and implementation of environmentally safe alternatives to traditional land application.
3. Progress Report:
Laboratory tests were carried out to recover phosphorus from sludge using the quick wash process developed by ARS-Florence scientists (objective 1e). Results indicate that the quick wash process can selectively extract more than 80% of the phosphorus content from sludge. The process can produce biosolids low in phosphorus while it recovers the extracted phosphorus as a concentrated calcium phosphate salt. Conducted study on microbial community composition in four anaerobic lagoons using next generation DNA sequencing through deep 16S rDNA analysis of water columns (objective 1f). Preliminary results revealed distinct microbial communities for each lagoon that remained consistent throughout the depth of each water column. Three of the four lagoons were dominated by anaerobic bacteria, mostly Peptostreptococcus, Clostridium, and sulfur reducing bacteria. One lagoon had a large number of aerobic Mycobacteria indicating slightly oxidative conditions of the water column. Completed study to identify microbial markers in the water column of a swine lagoon fed with treated water from a second generation wastewater treatment system. The study included two adjacent lagoons, one fed with treated aerated water and the other one maintained anaerobic. Monthly samples were collected, and DNA extracted for downstream molecular analysis to identify organisms contained within each lagoon. This study assesses whether liquid from reclaimed lagoons can be safely used for irrigation free of pathogens (objective 1h). Completed study on effects of blending and pelletizing poultry litter with plant material feedstocks on biochar production by pyrolysis and chemical characteristics (objective 2a). Biochars were analyzed for their structural qualities, individual pellet strength, energy content and chemical composition. Results from this study show marked improvements on the energetic and chemical composition of biochars from poultry litter blended with switchgrass or pine chips. Field sampling was performed in transects across edge of the field and riparian buffer manure-impacted soils on five farm sites in North and South Carolina. This study is assessing nitrous oxide emissions and denitrification enzyme activity to provide guidelines to minimize nitrous oxide emissions from manure-influenced Coastal Plain soils (objective 3a). A laboratory microcosm experiment was conducted using manure-based designed biochars to test the effect of feedstock blend and particle size on both water storage and phosphorus movement through well- and poorly-drained sandy Coastal Plain soils (objective 4b). Poultry litter and swine solids were blended with plant materials, pelleted, and pyrolyzed to generate biochar. Data revealed that after three leaching events over 90 days, feedstock blend and biochar particle size of designed biochars can control the availability of phosphorus. Greenhouse experiments were conducted to test agronomic value of manure biochar (objective 4c). Two trials were completed using biochars made from manures that were added as phosphorus fertilizer sources to pots planted to cotton and soybean. The biochars performed as well as chemical fertilizer.
Cantrell, K.B., Martin, J.H. 2012. Stochastic state-space temperature regulation of biochar production Part I: Theoretical development. Journal of the Science of Food and Agriculture. 92:481-489.