Source: TEXAS A&M UNIVERSITY submitted to
A CLOSED-LOOP DAIRY SYSTEM BY AN INTEGRATED ANAEROBIC DIGESTION AND PYROLYSIS PROCESS FOR FOOD-ENERGY-WATER NEXUS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
NEW
Funding Source
Reporting Frequency
Annual
Accession No.
1018814
Grant No.
(N/A)
Project No.
TEX09764
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Apr 5, 2019
Project End Date
Apr 5, 2024
Grant Year
(N/A)
Project Director
Kan, EU.
Recipient Organization
TEXAS A&M UNIVERSITY
750 AGRONOMY RD STE 2701
COLLEGE STATION,TX 77843-0001
Performing Department
Stephenville-TAMU Agr Res Cntr
Non Technical Summary
Dairy farms, like other animal farms, have multiple threats against sustainable operation such as significant pollution in water, air and soil, food safety, water shortage and energy supply. Current management of dairy manure such as land application often causes significant water, air and soil pollution. High levels of nutrients and various antibiotics released into environment lead to algal blooms, eutrophication, nitrate accumulation and increase of antibiotic resistant bacteria. Land application of manure also drastically contributes to emission of odor and greenhouse gases from manure while causing soil acidity/infertility, which would decrease agricultural productivity. Composting can produce biofertilizers via microbial actions using dairy manure; however, it also causes drastic loss of ammonia and development of odors during the composting process. Anaerobic digestion has been suggested to resolve manure disposal, energy recovery and greenhouse gas control. Despite several advantages, it was found that anaerobic digestion suffered fluctuating performance, difficult operation, low yield of biogas, and the need to dispose of undigested sludge after digestion. Recently thermal disposal of manure such as pyrolysis and gasification has been studied to convert manure to bio-oil, syngas and biochar. However, thermal disposal of manure has revealed high energy consumption with high moisture of wet manure and low yields of energy (bio-oil and syngas).Proposed concept: A closed-loop dairy system by an integrated anaerobic digestion and pyrolysis processTo improve current anaerobic digestion and pyrolysis, an integrated pyrolysis and biochar process has been suggested to be a highly promising option for manure and wastewater treatment at dairy farms. However, so far there have been few systematic approaches to develop the pyrolysis-biochar process for dairy manure disposal, wastewater treatment, nutrient recovery and soil amendment. In this project I will address these critical issues with systematic investigation of an integrated anaerobic digestion and pyrolysis to overcome dairy farm-associated sustainable problems. The proposed dairy system combines anaerobic digestion (AD) and pyrolysis (PY) for intensifying food-energy-water at dairies. Flushed manure goes to an anaerobic digester as a bioreactor, where manure is converted to biogas, liquid and solid digestates. A PY unit integrated with AD convert mixture of AD digestate and waste hays to biochar and syngas. Syngas from PY and biogas from AD are fed to a combined heat and power generator (CHP) to make energy for supporting AD and PY. The total amount of electricity and heat generation from CHP is used to support energy consumption of pyrolysis and anaerobic digestion. The excessive electricity can be sold to bring an extra revenue. Biochars are added to AD for enhancing biogas production, process stability and manure disposal. Biochar are also amended with soil for increasing productivity of crops, vegetables, and forage grasses as well as soil fertility. The crops and forage grasses are recycled to feeding cows, while organic vegetables are sold for additional profits. Some biochar is made into activated carbon via steam activation process, which removes emerging contaminants such as antibiotics from AD liquid digestate. Some proportion of treated liquid digestate is irrigated to crops, vegetables and forage grasses while the rest is recycled for flushing manure. Excessive activated carbon can be also sold as water filtering media for additional profits. Therefore, the integrated AD and PY can overcome current limitations of AD and PY including treatment of enormous amounts of AD digestate, high energy consumption and decontamination of AD liquid digestate.
Animal Health Component
0%
Research Effort Categories
Basic
40%
Applied
60%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
40334992020100%
Goals / Objectives
The overall goal of this project is to enhance agricultural and environmental sustainability at dairy systems by an integrated anaerobic digestion and pyrolysis process.The specific objectives to achieve the goal of this project include:Objective 1: Develop a novel pyrolysis for production of energy, biochar, and activated biochar from anaerobic solid digestate of dairy manure mixed with waste hays at dairy systems.Objective 2: Develop an enhanced anaerobic digestion of dairy wastes with addition of biochar for increasing energy-water-food production.Objective 3: Develop treatment and reuse of anaerobic liquid digestate by biochar-derived activated carbon.
Project Methods
Task 1. Novel pyrolysis for production of energy, biochar, and activated carbon: The Biochars will be made from mixture of anaerobic solid digestate of dairy manure (AD) and waste hay (WH) at different ratios under various pyrolysis conditions (i.e., temperature, heating time and heating rate). Air dried AD and WH mixture will be pyrolyzed by using a quartz tube furnace. 100 g of AD and WH mixture will be loaded on a meshed container inside the reactor. Nitrogen will be used for purge gas with 1L/min flow rate. Based on our preliminary data and experience, the slow pyrolysis will be performed at three different temperatures (600, 700, and 800°C). The activated carbons will be also produced from the biochars via steam and chemical activation processes. For steam activation, 100 g of biochar with different AD/WH mixing ratios and operation conditions will be converted to activated carbon by purging steam from the bottom of the reactor at two different steam flow rates (60 and 120 ml/h) to investigate the influence of steam flow rate on surface structure development of activated carbon. During the steam activation, the reactor will be quickly heated to three different activation temperatures (600, 700, and 800°C) to determine the optimum activation temperature. For chemical activation, 100 g of biochar with different AD/WH mixing ratios and operation conditions will be mixed with NaOH at various ratios. The mixture of biochar and NaOH will be heated at 800-900 oC for 1-4 h under oxygen-limited condition for production of activated carbons. Physical and chemical properties of the biochars and activated carbons will be analyzed by various techniques. Carbon, hydrogen, and nitrogen content of the samples will be analyzed by using a PerkinElmer 2400 Series II elemental analyzer (PerkinElmer, Waltham, MA). Proximate analysis will determine volatile matter, fixed carbon, and ash contents using TA Q500 thermogravimetric analyzer (TA Instruments, New Castle, DE). The specific measurement condition followed modified ASTM D7582-15. BET surface area and micro pore volume of samples will be analyzed with a Gemini VII 2390 surface area analyzer (Micromeritics, Norcross, GA, USA). Specific functional groups associated with effective adsorption of nutrients and antibiotics will be analyzed by a FT-IR, Boehm titration and pH at point of zero charge measurement.Task 2. Enhanced anaerobic digestion (AD) with addition of biochar: Batch-mode anaerobic digestion experiments will be conducted in glass AD reactors based on well-known biochemical methane potential test. The experiments will be initiated by adding the anaerobic digestate-waste hay blended biochars to the AD reactors at various ratio. As the AD reactors will be incubated under mesophilic conditions for about 30 d, the biogas, biomethane and metabolites in the reactors will be monitored at regular intervals. The batch-mode AD experiments results will be fitted using kinetic models such as Modified Gompertz'd model to obtain the more detailed insight regarding the effects of addition of biochar in AD. Using the optimal conditions derived from the batch-mode AD experiments results, lab-scale continuous AD will be tested. Prior to continuous operation, all reactors (working volume of 3L) will be operated in batch mode for two weeks. Biochar (based on batch test) added and non-added reactors will be operated at same hydraulic retention time (HRT). All reactors will be operated as a continuous stirred-tank reactor with complete mixing. All experiments will be conducted in duplicated at the same experimental conditions. Samples were obtained from all reactors at intervals of about three days. The composition of biogas will be quantified using a gas chromatograph equipped with a thermal conductivity detector and a flame ionization detector. The water quality in the AD such as total solids, volatile solids, total/soluble COD, total nitrogen, ammonium, nitrate, total phosphate, antibiotics and hormones will be analyzed by standard methods, Hach kits and HPLC.Task 3. Activated biochar for AD liquid digestate treatment: I will investigate the adsorption capacities of selected activated carbon made from biochar in Task 1 for antibiotics (i.e., tetracycline (TC), sulfamethoxazole (SMX)) and hormones (i.e., 17 alpha-estradiol (EE)) over a range of concentrations detected in the AD liquid digestate in Task 2. In addition to measurement of the antibiotics and hormone, microbial pathogens will be also monitored in a sand column and an activated biochar-filled column due to possible adsorption of these contaminants on biochar as others reported. Microbial communities and pathogens in the AD liquid digestate (liquid effluents from AD) before and after treatment with activated carbon made in this project will be analyzed. First, adsorption isotherms for each antibiotics and hormone (TC, SMX, EE) onto the selected activated carbon will be investigated in flaks. The adsorption experiments will be conducted by vigorously stirring 0.1 g of activated carbon and 20 mL of synthetic wastewater (DI water + each contaminant) at various inlet concentrations for 2-3 d until it reaches equilibrium. Adsorption isotherm models including the Langmuir and Freundlich models will be fitted with experimental data to understand the major mechanism of adsorption and maximum adsorption capacity. The adsorption kinetics for each contaminant will also be developed to fit to pseudo-first-order, pseudo-second-order, or intraparticle diffusion equations for helping us to design and model the adsorption process. A HPLC with a fluorescence detector and pre-condensation using C18 SPE cartridges will be employed for analysis of TC, SMX and EE at low concentration. Unlike a synthetic wastewater (contaminants in a DI water), the AD liquid digestate contains multiple organic and inorganic contaminants which may interfere with adsorption of antibiotics and hormone onto the selected activated carbon. The actual AD liquid digestate obtained from Task 2 will be treated with the selected activated carbon to clearly evaluate removal efficiency and any interference of other compounds on the adsorption capacities. The operating conditions such as solution pH, dose of activated carbon (0 - 10 g activated carbon per L of liquid effluent), and contact time will be optimized via a serious of adsorption tests as described for the adsorption in the synthetic wastewater.

Progress 10/01/19 to 09/30/20

Outputs
Target Audience:1) Dairy producers in Texas and Texas Dairymen Association 2) North Texas Biochar Initiative 3) Federal agencies such as US EPA, USDA, USDA National Resources Conservation Service 4) Scientific Groups including the faculty at Texas A&M University and Tarleton State University, and American Institute of Chemical Engineers Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project provided various training and professional development opportuinities to the postdoc researcher, graduate and undergraduate students. Through the laboratory experiments, they learned various principles including biology, chemistry, environmental science and agricultural technology. They also learned various skills such as statistial analysis, engineering calculation, material characterization (for biochar) and thermal process (pyrolysis). The postdoc, graduate and undergraduate students published several journal articles and presented at the National Conferences. How have the results been disseminated to communities of interest?1) The major results were published in the top peer-reviewed journals, and presented at the National Conferences. 2) Some of results were shared with North Texas Biochar Initiative whcih has beeen supported from the Rural Economic Development Program at USDA. 3) The major outcomes were used for new grant proposals submitted to USDA. What do you plan to do during the next reporting period to accomplish the goals?1. I will produce varous types of raw and functionalzied biochar from agriculutral waste. The biochars will be applied to removal antibiotics and nutrients from soil and wastewater. Possible interactions among biochar-soil-bacteria-plant will be also investigated for developing biochar-enhanced environmental remediation. 2. I will enhance anaerobic digestion of dairy manure and solid waste using biochar addition, chemical/physical pretreatment and process optimization. The enhanced AD process will be fully understood in terms of biogas production, metabolites production, contaminants and fertilizer values. 3. The manure and hay biochars will be used for recovery of nutrients from dairy lagoon effluents while the nutrient-saturated biochar will be evaluated for its fertilizer value. In addition, the dairy effluent- and manure-saturated biochar will be tested to plant growth in the greenhouse.

Impacts
What was accomplished under these goals? 1. The multifunctional biochar from dairy manure and waste hays were developed for removal of antibiotics, BPA and algal toxins in wastewater. The multifunctional biochar was prepared via a novel pyrolysis and surface modification. The multifunctional biochar showed high adsorption of antibiotics, algal toxins and BPA. 2. The mixture of dairy manure and waste hay at various ratios (100/0, 75/25,50/50, 25/75, 0/100) were converted to biochar via pyrolysis at 350,550 and 750 oC. All of the biochar products were tested with the dairy wastewater in terms of nutrient recovery and antibiotics removal. A couple of biochar products showed highest removal of antibiotics and recovery of N and P. Their adsorption capacities will be investigated through isotherm and kinetic analysis. 3. Further development of biochar-enhanced anaerobic digestion of dairy manure: The addition of biochar to anaerobic digestion of dairy manure showed enhancement in biogas production. Besides, further analysis of this process was made to understand chemical compositions of solid and liquid AD digestate and fertilizer value of liquid AD digestate from the biochar-enhanced AD of dairy manure. As a result of further anlaysis, the biochar-enhanced AD provided higher fertilizer value with lower contaminants and metabolites. 4. Treatment of dairy effluent by biochar-derived activated carbon: The chemically activated biochar and metal-activated biochar were produced under the optimum pyrolysis conditions (800 oC, 2h). Both activated biochars showed high removal of antibiotics in dairy effluent and effective regeneration capacity using physical and chemical regeneration methods.

Publications

  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Choi YK, Choi TR, Gurav R, Bhatia SK, Park YL, Kim HJ, Kan E, Yang YH. 2020. Adsorption behavior of tetracycline onto Spirulina sp. (microalgae)-derived biochars produced at different temperatures. Science of The Total Environment, 710: 1-13.
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Jang HM, Brady J, Kan E*. 2021. Succession of microbial community in anaerobic digestion of dairy manure induced by manure-derived biochar. Environmental Engineering Research. 26(1): 1-10.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Choi YK, Srisvan R, Kan E*. 2020. A novel hay biochar functionalized with dairy effluent for removal of tetracycline in water. ACS Omega, 5(27), 16521-16529.
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Zeng S, Choi YK, Kan E*. 2021. Iron-activated bermudagrass-derived biochar for adsorption of aqueous sulfamethoxazole: Effects of iron impregnation ratio on biochar properties, adsorption, and regeneration. Science of The Total Environment, 750: 141691.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Wallace AR, Su C, Choi YK, Kan E, Sun W. 2020. Removal of Fluoride from Water Using a Calcium Modified Dairy Manure Derived Biochar. Journal of Environmental Engineering, 146(12), December 2020.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Zeng S, Kan E*. 2020. Chemically activated Bermudagrass-derived biochar for effective removal of sulfamethoxazole in water. ACS Omega, 5(23), 1379313801.
  • Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Pinkerton TC, Assi AT, Pappa VA, Kan E, Mohtar RH. 2020. Impact of Dairy Wastewater Irrigation and Manure Application on Soil Structural and Water Holding Properties. submitted to ASABE.
  • Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Zeng S, Kan E. 2020. Adsorption and Regeneration on Iron-Activated Biochar for Removal of Microcystin-LR. submitted to Chemosphere.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Zeng S, Kan E. 2020. FeCl3 Activated Bermudagrass-Derived Biochar for Removal of Cyanotoxins in Water: Characterization, Adsorption and Regeneration. 2020 AIChE (American Institute of Chemical Engineers) Annual Meeting, November 16-20, 2020.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Gibbs T, Kan E. 2020. A Novel Functionalized Hay-Derived Biochar for Recovery of Phosphorus Fertilizer from Dairy Wastewater. 2020 AIChE (American Institute of Chemical Engineers) Annual Meeting, November 16-20, 2020.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Harris R, Zeng S, Kan E. 2020. Enhanced Anaerobic Digestion of Dairy Manure with Addition of Hay-Derived Biochar. 2020 AIChE (American Institute of Chemical Engineers) Annual Meeting, November 16-20, 2020.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Zeng S, Kan E. 2020. Iron-Activated Waste Hay-Derived Biocarbon for Removal of Antibiotic Sulfamethoxazole in Water. 2020 AIChE (American Institute of Chemical Engineers) Annual Meeting, November 16-20, 2020.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Zeng S, Kan E. 2020. Heterogeneous Fenton-like Oxidation Using a Novel Iron-Activated Bermudagrass-Derived Biochar for Removal of Aqueous Antibiotic Sulfamethoxazole. 2020 AIChE (American Institute of Chemical Engineers) Annual Meeting, November 16-20, 2020.


Progress 04/05/19 to 09/30/19

Outputs
Target Audience:1) Dairy producers in Texas and Texas Dairymen Association 2) North Texas Biochar Initiative 3) Federal agencies such as US EPA, USDA, USDA National Resources Conservation Service 4) Scientific Groups including the faculty at Texas A&M University and Tarleton State University, and American Institute of Chemical Engineers Changes/Problems:Up to date, there have been no major problems and challenges in this project. Some minor problems and challenges include fluctuating manure quality, heterogeneous properties of biochar and multiple impurities in manure inferering analysis of antibiotics in dairy effluents. For overcoming these challenges, frequent sampling and analysis of dairy manure and careful evaluation of biochar properties were conducted. In addition, the solvent extraction and solid phase extraction before the analysis of antibiotics by HPLC and LC/MS were developed for minimizing inferering analysis of antibiotics. What opportunities for training and professional development has the project provided?The project provided various training and professional development opportuinities to the postdoc researcher, graduate and undergraduate students. They learned the principles of biology, chemistry, environmental science and agricultural technology from this project which could apply for various processes in environmental and agricultural applications. They also learned various skills such as statistial analysis, engineering calculation, material characterization (for biochar) and thermal process (pyrolysis). The postdoc (Dr. Hyunmin Jang) got an assistant professor position from one of Korean Universities (Jeonbuk University) right after conducting this project. The graduate and undergraduate students published the journal articles and presented at the National and International Conferences. How have the results been disseminated to communities of interest?1) The major results were published in the top peer-reviewed journals, and presented at the National and International Conferences. 2) The major results were also presented to the dairy producers and the state agencies during "Dairy day" at Southwest Regional Dairy Center at Tarleton State University. 3) Some of results were shared with North Texas Biochar Initiative whcih has beeen supported from the Rural Economic Development Program at USDA. What do you plan to do during the next reporting period to accomplish the goals?1. I will develop multifunctional biochar from dairy manure and waste hays for removal of antibiotics andmicrobial pathogens including antibiotic resistant bacteria which are currently released from dairy effluents. The multifunctional biochar will be prepared by novel pyrolysis and surface modification processes. The multifunctional biochar will be also applied to other contaminants such as cyanotoxin (from algal bloom) and PFAS (Per- and polyfluoroalkyl substances) in water and wastewater. 2. Novel anaerobic digestion of dairy manure will be developed for enhancing biogas/biometahne production, recovering nutrients and valuable metabolites from anaerobic digestate, and eliminating antibiotics, microbial pathogens and antibiotic resistant bacteria from liquid anaerobic digestate. 3. The biochar or activated biochar-driven processes will be developed for recovery of nutrients and valuable chemicals eliminationg microbial pathogens from dairy effluent and liquid anaerobic digestate. The nutrient-saturated biochar will be applied for enhancing plant growth and soil fertility. The dairy effleunt treated by the biochar will be reused for agricultural irrigation and dairy production facilities.

Impacts
What was accomplished under these goals? 1. Production of biochar and activated biochar from dairy manure and waste hays via novel pyrolysis processes: The metal (iron)-catalyzed pyrolysis and alkaline-deriven activation processes were developed for production of cost effective biochar and activated biochar (activated carbon) from dairy manure, waste hays (Bermudagrass, alfalfa), sewage sludge and wood. 2. Enhanced anaerobic digestion of dairy manure with addition of biochar: The addition of dairy manure and hay-derived biochars to the anaerobic digestion of dairy manure enhanced the biogas/biomethane production by a factor of 1.2-1.5 while minimizing the process time by 35% and reducing the microbial pathogens and antibiotic resistant bacteria in the manure effluent. 3. Treatment of dairy effluent and anaerobic liquid digestate by biochar-derived activated carbon: The antibiotics and antibiotic resistant bacteria in the dairy effluent and anaerobic liquid digestate were significatly elimiated by the activated biochar made from the dairy manure and waste hays. The activated biochar possessed high surface area (1000-2000 m2/g) and various functional groups including metals resulting in effective removal of antibiotics and antibiotic resistant bacteria. 4. Recovery of nutrients in dairy effleunt using the biochar: The biochars were also used for recovery of nutrients, particularly phosphorus, from the dariy effluent.

Publications

  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Choi YK, Jang HM, Kan E*, Rose AR, Sun W. 2019. Adsorption of phosphate in water on a novel calcium hydroxide-coated dairy manure-derived biochar. Environmental Engineering Research, 24(3): 434-442.
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Jang HM, Yoo SH, Park SK, Kan E*. 2019. Engineered biochar from pine wood: Characterization and potential application for removal of sulfamethoxazole in water. Environmental Engineering Research, 24: 608-617
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Jang HM, Choi SK, Shin JY, Kan E, Kim YM. 2019. Additional reduction of antibiotic resistance genes and human bacterial pathogens via thermophilic aerobic digestion of anaerobically digested sludge. Bioresource Technology, 273: 259-268.
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Jang HM, Kan E*. 2019. A novel hay-derived biochar for removal of tetracyclines in water. Bioresource Technology, 274: 162-172.
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Cho YK, Kan E*. 2019. Effects of pyrolysis temperature on the physicochemical properties of alfalfa-derived biochar for the adsorption of bisphenol A and sulfamethoxazole in water. Chemosphere, 218: 741-748.
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Jang HM, Kan E*. 2019. Engineered biochar from agricultural waste for removal of tetracycline in water. Bioresource Technology, 284: 437-447
  • Type: Journal Articles Status: Accepted Year Published: 2019 Citation: YK Choi, TR Choi, R Gurav, SK Bhatia, YL Park, HJ Kim, E Kan, YH Yang 2019. Adsorption behavior of tetracycline onto Spirulina sp. (microalgae)-derived biochars produced at different temperatures
  • Type: Journal Articles Status: Under Review Year Published: 2019 Citation: Jang HM, Brady J, Kan E*. 2019. Microbial community changes in anaerobic digestion of dairy manure with addition of manure-derived biochar.
  • Type: Journal Articles Status: Under Review Year Published: 2019 Citation: YK Choi, R. Srinivasan, Kan E. 2019. A novel hay biochar functionalized with dairy effluent for removal of tetracycline in water.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Zeng S, Park SH, Yoo SH, Park SK, Kan E. 2019. Effects of mechanical refining on anaerobic digestion of dairy manure. International Environmental Engineering Conference, December 10-13, 2019, Pusan, Korea.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Choi YK, Kan E. 2019. Effective removal of inorganic and organic contaminants in wastewater using a waste hay-derived biochar. International Environmental Engineering Conference, December 10-13, 2019, Pusan, Korea.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Choi YK, Zeng S, Kan E. 2019. A waste hay-derived biochar for removal of cyanotoxins in water. International Biochar World Congress 2019, November 10-13, 2019, Seoul, Korea.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Jones BW, Smith WB, Lambert BD, Muir JP, Kan E. 2019. Effects of garlic extract and citrus flavonoid feed additive on dairy cow performance. American Dairy Science Association, Cincinnati, OH, June 23-26, 2019.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Selph LE, McGahan, DG, Kan E, Muir JP. 2019. Effects of Pre-Enriched Manure and Cellulosic Biochars on Soil Physiochemical Properties and Forage Growth. San Antonio, TX. 2019 ASA-CSSA-SSSA International Annual Meeting, November 10-13, 2019, San Antonio, Texas.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Selph, LE, McGahan DG, Muir JP, Kan, E. 2019. Feeding better biochar to Bermuda grass: Investigation of physiochemical impact. Soil Survey and Land Resources Workshop. College Station, Texas.