Source: UNIVERSITY OF ARKANSAS submitted to
SUSTAINING AGRICULTURAL PRODUCTION BY PROTECTING WATER AND PRODUCING RENEWABLE ENERGY FROM PRODUCTION WASTES
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
1003122
Grant No.
(N/A)
Project No.
ARK02444
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Jun 10, 2014
Project End Date
Sep 30, 2018
Grant Year
(N/A)
Project Director
Zhu, JU, .
Recipient Organization
UNIVERSITY OF ARKANSAS
(N/A)
FAYETTEVILLE,AR 72703
Performing Department
Biological & Agr Engineering
Non Technical Summary
The long-term viability of agriculture as a source for food, feed fiber and fuels will depend on our ability to reconcile agricultural production with environmental integrity. And research on sustainable production systems is thus crucial to developing the knowledge base to implement required agricultural innovations. This AES project proposal will focus on exploring and developing different, innovative technologies that will lead to a comprehensive utilization of various agricultural production wastes including animal wastes with poultry litter in particular, crop residues such as rice straw, and dairy and swine manure and the production of bioproducts and bioenergy through physic-chemical and biological conversions. Anaerobic digestion will be employed to co-treat poultry litter with other liquid manure streams (such as swine and dairy) to overcome the low moisture content of poultry litter, with all the process parameters such as carbon/nitrogen ratio, pH, organic loading rate, etc., being optimized. Also, solid-state digestion will be investigated as well. Beneficial use of digested solids for mushroom production by fungi will be another part of study to determine its feasibity of applications. In addition, a complete system to treat liquid animal manure to generate biohydrogen, biomethane, and a slow release fertilizer (struvite) will be developed in this project. Using crop residues to produce fumaric acid via a two stage process (acid hydrolysis and fungal fermentation) will also be explored. The information and knowledge obtained from this project will be shared with the public through both refereed and non-refereed journal publications, extension/education events, classroom teaching, and among others. The ultimate goals of this research will be to protect the soil and water and natural resources in Arkansas by reducing the volume of wastes produced and maximizing the value-added products production and environmental benefits so the agricultural production in the State can be sustained in a long run.
Animal Health Component
0%
Research Effort Categories
Basic
30%
Applied
50%
Developmental
20%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
40332992020100%
Knowledge Area
403 - Waste Disposal, Recycling, and Reuse;

Subject Of Investigation
3299 - Poultry, general/other;

Field Of Science
2020 - Engineering;
Goals / Objectives
The goals of this AES project proposal will focus on exploring and developing different, innovative technologies to reduce the impact and footprint of agricultural production on the environment and its demands for natural resources. These technologies will lead to a comprehensive utilization of various agricultural production wastes including animal wastes with poultry litter in particular, crop residues such as rice straw, and dairy and swine manure and the production of bioproducts and bioenergy through physical-chemical and biological conversions. Two broad objectives will be accomplished (or substantially studied) during the period of the project, 1) Poultry litter treatment and reuse technologies development and 2) Developing agricultural wastes based technologies for bioenergy and chemicals production. The ultimate goals of this research will be to protect the soil and water and natural resources in Arkansas, and in the nation as well, by reducing the volume of wastes produced and maximizing the value-added products production and environmental benefits so the agricultural production in the States can be sustained in a long run.
Project Methods
Since there are two major research areas in this project, the methods will be presented based on the specific objectives listed under each major research area.Research area 1: developing applicable anaerobic digestion technologies for poultry litterObjective 1: Co-digesting poultry litter with other animal wastesIn this project, different mixing ratios of poultry litter with either liquid swine or dairy manure will be investigated to determine the feasibility of this technology based on biogas production, methane content in biogas, volatile solids destruction, COD and BOD reduction.Objective 2: The effect of carbon/nitrogen ratio, temperature, and pHIn this study, four C/N ratios will be investigated, i.e., 15/1, 20/1, 25/1, and 30/1 to determine the optimal C/N ratio for biogas production and reduction in COD and BOD. With varying C/N ratios, a range of three pH values (6.5, 7.0, and 7.5) will also be investigated at the same time, which comprises a 3x4 experimental design. Batch tests will be employed using 1 L flasks as digesters and the total volume of biogas produced will be measured using the water displacement method. The methane and CO2 content of the biogas will be determined using a gas chromatograph. All the experiments will be carried out under mesophilic temperature condition (37oC).Objective 3: The effect of hydraulic retention time (HRT) and organic loading rate (OLR)A continuous, lab-scale anaerobic sequencing batch reactor (ASBR) system will be built to investigate the effect of HRT and OLR on the co-digestion performance of poultry litter. Four HRT (3, 6, 9, and 12 days) will be examined with 3-4 OLRs to determine the optimal running parameters in terms of pH, HRT, C/N ratio, and OLR for the methane ASBR to produce methane continuously and efficiently. Information obtained can be used to design a scale-up reactor that can be transferred into a pilot-scale system for farm use.Objective 4: Solid state digestion of poultry litterThe basic idea is to extract the ammonia, which is detrimental to the digestion process, before digestion. There are a number of methods to extract ammonia from poultry litter including using water, chemicals, and even ammonia strippers. However, soaking poultry litter in water to solubilize ammonia initially present is a simple but potentially more applicable method that has not been extensively examined. The solids digestion after ammonia extraction needs more research to determine the maximal solids level that the digestion process can handle. The outcomes from this project may lead to an applicable technology for on-farm treatment of poultry litter cost effectively.Objective 5: Beneficial use of the solid fraction of the digestates Experiments will be designed to examine two fungi species, Pleurotus ostreatus and Agrocybe aegerita, for breaking down lignocellulosic residues in the digestate to produce mushroom. Rice straw (RS) will be chopped to 5 cm pieces and then mixed with the digestate solids (DS) at different levels (RS/DS: 100, 85, 70, 55, 40, 25, 10, 0). A single factor randomized design with eight levels of the factor combinations will be adopted for this study. Each substrate combination will be replicated in four bags and a random sample will be taken from each bag for a total of 32 experimental units. Mushroom yields, lignocellulosic enzyme production and substrate utilization, and mushroom fruit body production in relation to lignocellulosic enzyme activity will be the variables to be investigated.Research area 2: Developing agricultural wastes based technologies for bioenergy and chemicals productionObjective 1: Fumaric acid production from crop residues such as rice straw, corn stover, etc.The overall scientific/technical approach and objectives include developing and evaluating a novel, two-stage strategy to effectively use the sugars contained in rice straw/corn stover to produce fumaric acid by R. oryzae via fermentation by 1) treating rice straw/corn stover with dilute acid at different levels to determine the best dosage to maximize xylose concentration in the treated liquid for fungal growth; 2) treating the solid residues from the acid treatment with enzymatic hydrolysis to produce a glucose rich liquid; and 3) producing fumaric acid from the glucose rich liquid by enriched R. oryzae biomass via fermentation.Objective 2: Co-treatment of animal manure and other wastes to produce valuable products and reduce water pollutionOverall scientific/technical approach and objectiv es include 1) determining the optimal values of operating parameters for a hydrogen fermenter fed on agricultural production waste materials such as animal manure and/or mixture of manure and other crop residues, hydraulic retention time (HRT), and pH) to maximize hydrogen production; 2) determining the optimal values of operating parameters for an anaerobic sequencing batch methane digester (ASBR) (such as organic loading and HRT) receiving the effluent from the hydrogen fermenter to maximize methane generation and COD reduction; 3) developing an absorption reactor to remove CO2 and H2S in biogases from both the hydrogen fermenter and methane digester using NaOH as an absorbent; 4) developing a process to recover nitrogen and phosphorus in the ASBR effluent by forming struvite, a slow release fertilizer; and 5) evaluating a complete lab-scale system consisting of a hydrogen fermenter, an ASBR methane digester, a CO2 removal reactor, and a struvite precipitator to co-treat swine manure and sugar waste molasses. The proposed treatment system is aimed at continuous production of hydrogen, methane, and struvite from one, two, or more waste streams and the information from the lab-scale experiments will provide key information for further scale-up design of the treatment system and its operations.Information delivery and disseminationInformation generated will be presented in both technical and non-technical formats, including refereed journal publications for pundits and other outlets for lay people such as extension publications, aiming at distributing the information across the nation, and the world as well. Under the same token, the obtained outcomes will also be included in the course materials for classroom teaching.

Progress 06/10/14 to 09/30/18

Outputs
Target Audience:The target audiences reached by this researchinclude the scientific community and the concerned industries by threejournal articles and twopapers presented in the Annual Meeting of American Society of Agricultural and Biological Engineers over thisperiod of project. . Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Over the project period, the opportunities provided by this project for training and professional development include providing training to postdocs, MS and PhD students,undergrad honors students, and First-YearEngineering Program undergrad students in conducting research and obtaininghands-on experience in conducting experiments, analyzing and compiling data, and writing scientific publications. How have the results been disseminated to communities of interest?Over the entire project period, there are 8refereed journal articles and 9non-refereedASABEpapersmade available to the public, through which the research information was disseminated to a variety of users and stakeholders. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The objectives of this project havebeen successfullyaccomplished. For Objective 1, poultry litter treatment by anaerobic digestion was extensively studied with key affecting factors identified, such as carbon/nitrogen ratio, co-digestion with wheat straw,and total solids content. The digested water was further treated with technologies such as ammonia stripping to remove nitrogen, and about 80% of ammonia in the liquid could be stripped by placing the water in a sealed vessel under below atmospheric pressure and raised temperature. With the ammonia removed, the water could be recycled back to the digester for further use as a dilution agentfor incoming poultry litter. Objective 2 was accoplished by researching and developing advanced technologies, such as enrichment of volatile fatty acids via anaerobic digestion, which can be used in denitrification to remove nitrogen without needing to add an external carbon source, and microbial fuel cell development using liquid animal manure as substrate to produce electricity. These technologies can effectively reduce the demand on natural resources and sustain the growth of animal industry.

Publications

  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Shen, J., J. Zhu. 2018. Kinetics of poultry litter in a leach bed reactor with agitation based on two mechanisms: enzymatic hydrolysis and direct solubilization. Biochemical Engineering Journal 135 (15): 115-122.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Wu, S., L. Chen, J. Zhu, M. Walquist, D. Christian. 2018. Pre-digestion to enhance volatile fatty acids (VFAs) concentration as a carbon source for denitrification in treatment of liquid swine manure. J. Environ. Sci. Health Part A 53(10): 891-898.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Wu, S., L. Chen, J. Zhu. 2018. Enhancing volatile fatty acids concentration by pre-digestion to be used as a carbon source for denitrification in liquid swine manure treatment. ASABE Annual International Meeting paper#: 1800068, Detroit, MI. July 29-Aug.1, 2018.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Wu, S., S. Deng, H. Hsie, J. Zhu. 2018. Evaluation of a novel liquid plasma reactor to convert soybean oil to biodiesel. ASABE Annual International Meeting paper#: 1800194, Detroit, MI. July 29-Aug.1, 2018.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Lin, H., S. Wu, J. Zhu. 2018. Modeling power generation and energy efficiencies in air-cathode microbial fuel cells based on Freter equations. Applied Science 8(10):1983.


Progress 10/01/16 to 09/30/17

Outputs
Target Audience:The target audiences reached by this research include the scientific community and the concerned industries by three journal articles and two papers presented in the Annual Meeting of American Society of Agricultural and Biological Engineers in Spokane, WA from July 16 to July 20, 2017. Changes/Problems:No changes to the project. What opportunities for training and professional development has the project provided?The opportunities provided by this project for training and professional development include providing training to PhD student, undergrad honors students, and Freshmen Engineering Program undergrad students in conducting research and obtaining hands-on experience in analyzing and compiling data. How have the results been disseminated to communities of interest?Listed in the "Product" section are the results of this research that have been disseminated to users through refereed journal publications and conference papers and presentations. In this period, there are 3 refereed journal articles and two ASABE papers were made available to the public. What do you plan to do during the next reporting period to accomplish the goals?Whether using anaerobic digestion technique to treat dry poultry litter is successful depends on the water treatment technology development, which means that if the nutrients in the digester effluent can be effectively removed, and the water cleaned, the water can be recycled back to the digester for further use without interfering with the normal digester performance. Research in this aspect will continue to search and develop cost effective technologies to clean up the effluentl. The construction of a lab-scale litter digester is close to completion and some preliminary trials were carried out to test the operational feasibility of the device. More work will be done to improve the digestion efficiency and the water cleaning effectiveness. Some advanced water cleaning technologies may also be looked into to determine the feasibility of using these technologies for water treatment. The outcomes of this research will be reported in the next reporting period.

Impacts
What was accomplished under these goals? Modified Gompertz model has been widely used to simulate the kinetics of microbial growth and bio-products production. However, the intrinsic shortcoming of this model rests with its inability of meeting the initial condition of bio-products. A general Gompertz model for microbial growth and its 2-parameter form were developed in this study, both of which can reduce to the original Gompertz model. The developed model for microbial growth was further extended to account for bio-products and substrate consumption by means of the corresponding yield coefficients. All the models developed herein could meet the initial conditions of microbial growth, bio-products, and substrate consumption. Batch experiments of anaerobic co-digestions of poultry litter and wheat straw at 2% total solids level consisting of 100, 75, and 50% VS of poultry litter were conducted to verify the model. The maximum specific methane volumes were obtained to be 207, 134, 5.18 mL (g VS)?1 for 50, 75, and 100% VS co-digestion, respectively. The developed model for bio-products was successfully applied to cumulative methane volumes produced from anaerobic co-digestion. The model parameters obtained from the bio-products model combined with the corresponding yield coefficients were applied to the microbial and substrate models to predict the microbial and substrate changes during co-digestion, with the relative errors being less than 2.21% for the former and 4.46% for the latter, respectively.

Publications

  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Shen, J., J. Zhu. 2017. Development of general Gompertz models and their simplified two-parameter forms based on specific microbial growth rate for microbial growth, bio-products and substrate consumption. Advances in Biotechnology & Microbiology 4(3): 555640. DOI: 10.19080/ AIBM.2017.04.555640.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Shen, J., J. Zhu. 2017. Methane production in an upflow anaerobic biofilm digester from leachates derived from poultry litter at different organic loading rates and hydraulic retention times. Journal of Environmental Chemical Engineering 5:5124-5130.
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Shen, J., J. Zhu. 2017. Modeling kinetics of anaerobic co-digestion of poultry litter and wheat straw mixed with municipal wastewater in a continuously mixed digester with biological solid recycle using batch experimental data. Chemical Engineering Communications 204(4):501-511.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Shen, J., J. Zhu. 2017. Role of Hydrolysis in Two-phase Anaerobic Digestion System for Poultry Litter. ASABE Annual International Meeting paper#: 1700072, Spokane, WA. July 17-20, 2017.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Shen, J., J. Zhu. 2017. Simulation of Unstable Kinetics of Continuously Mixed Anaerobic Digester with Biological Solid Recycle using Parameters Obtained from Batch Experiments. ASABE Annual International Meeting paper#: 1700073, Spokane, WA. July 17-20, 2017.


Progress 10/01/15 to 09/30/16

Outputs
Target Audience:The target audiences reached by this research include the scientific community and the concerned industries by two journal articles and three papers presented in the Annual Meeting of American Society of Agricultural and Biological Engineers in Orlando, FL, from 7/18-7/20/16. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project has provided opportunities for training and professional development for one post-doc, one PhD student, one MS student, one Brazilian Summer Intern, and two Freshmen Engineering Program undergrad students. How have the results been disseminated to communities of interest?As indicated in the "Product" section, The results of this research have been disseminated to users mainly through publications including refereed and non-refereed avenues, totaling 2 refereed journal articles and three ASABE papers presented at the conference. What do you plan to do during the next reporting period to accomplish the goals?The research of using anaerobic digestion technique for treating dry poultry litter has entered a critical stage, i.e., whether the recycled water meets the standard that allows it to be recirculated back to the digester for further use without impairing the digestion performance. The next step will focus on developing and evaluating not only an advanced digester but also techniques to treat the digester effluent to remove ammonia and phosphorus so that it can be recycled back to the digester. Different types of wastewater treatment techniques will be investigated and the outcomes will be reported in the next report.

Impacts
What was accomplished under these goals? In this report period, we have focused on modeling the kinetics of the anaerobic digestion process of poultry litter under differenct ratios of total solids levels composed of a mixture of poultry litter and wheat straw. With the experimental data from batch studies, we developed methods to quantify the half-saturation rate coefficient and maximum rate constant in the Monod model, yield coefficient of microbial mass to substrate mass, and endogenous decay coefficient, which are important kinetic parameters for design of anaerobic digestion process. These kinetic parameters are usually determined from a continuous stable operation of anaerobic digestion, which is more difficult and complex than batch operation in laboratory scale. In this report, a novel method has been developed to determine those parameters from data of batch experiments. To verify this method, the kinetics of batch anaerobic co-digestion of poultry litter and wheat straw mixed with municipal wastewater at three total solid (TS) levels (2, 4, and 8% TS) and 50% volatile solid (VS) of wheat straw (VSWS) was investigated. The experiments showed that the maximum specific methane volume (209 mL (initial g VS)-1)) was reached at 4% TS of 50% VSWS. Using the developed method, the kinetic parameters of endogenous decay coefficient, yield coefficient, maximum rate constant, and half-saturation coefficient in the Monod model were determined to be between 0.57x10-3 and 1.2x10-3 d-1, 0.00938 and 0.0644 g volatile suspended solid (VSS) (VS)-1, 1.394 and 13,797 d?1, and 1.6x10-8 and 99,996 g. The kinetic parameters obtained were used to simulate kinetic behaviors of a continuous mixed digester with biological solid recycle. The simulated results showed that the dilution rate was very significant for methane volume produced and VS and VSS concentrations in digestion operation. The maximum methane volume could be predicted to be 3071 and 4152 mL for 2 and 4% TS, respectively. More inoculum could reduce the digester startup time to achieve the maximum methane yield.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Shen, J., J. Zhu. 2016. Kinetics of biogas production in batch anaerobic co-digestion of poultry litter and wheat straw mixed with municipal wastewater. ASABE Annual International Meeting paper#: 162458093, Orlando, FL. July 17-20, 2016.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Shen, J., J. Zhu. 2016. Biogas production in a biofilm reactor of a two-phase anaerobic digestion system from hydrolysate derived from poultry litter at different organic loadings and retention times. ASABE Annual International Meeting paper#: 162460548, Orlando, FL. July 17-20, 2016.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Shen, J., J. Zhu. 2016. Development of a novel strategy for estimation of endogenous decay and yield coefficients in batch biogas production of anaerobic co-digestion of poultry litter and wheat straw using numerical integration. ASABE Annual International Meeting paper#: 162457488, Orlando, FL. July 17-20, 2016.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Shen, J. and J. Zhu. 2016. Kinetics of batch anaerobic co-digestion of poultry litter and wheat straw including a novel strategy of estimation of endogenous decay and yield coefficients using numerical integration. Bioprocess and Biosystems Engineering 39(10): 1553-1565. DOI 10.1007/s00449-016-1630-9.
  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Shen, J. and J. Zhu. 2016. Optimization of methane production in anaerobic co-digestion of poultry litter and wheat straw at different percentages of total solid and volatile solid using a developed response surface model. J. Environ. Sci. Health Part A 51(4): 325-334. DOI: 10.1080/10934529.2015.1109395.


Progress 10/01/14 to 09/30/15

Outputs
Target Audience:The target audiences reached by this research include the scientific community and the concerned industries by two papers presented in the Annual Meeting of American Society of Agricultural and Biological Engineers in New Orleans, LA, from 7/26-7/30/15. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?To date, this project has provided professional training to one post-doctorate trainee, one MS graduate, and two Freshmen Engineering Program undergrad students. How have the results been disseminated to communities of interest?The results of this research are disseminated to users mainly through publications including refereed and non-refereed avenues. As indicated early, two ASABE papers were presented at the conference, and two refereed articles are under review and will be published next year. What do you plan to do during the next reporting period to accomplish the goals?The work on using liquid digestion technology to treat dry poultry litter will continue with focus on recycling the process water. Currently, a treatment step is added to the digester system, aiming at reducing the ammonia and COD/BOD content of the effluent from the digester. The treated water will then be circulated back to the digester for further use. The water treatment step comprises a biofilm reactor to accomplish ammonia oxidation and organics removal. The results of current work will be reported in the next report.

Impacts
What was accomplished under these goals? Poultry litter is good feedstock for biogas (mainly containing methane) production using anaerobic digestion. In this period of reporting, methane production in batch anaerobic co-digestion of poultry litter and wheat straw was investigated for two factors (total solid percentage, and wheat straw percentage in a mixture of poultry litter and wheat straw) at three levels (2%, 5%, and 10% total solid, and 0, 25, and 50% of wheat straw). The results showed that co-digestion of poultry litter and wheat straw enhanced methane volume, and decreased the inhibition of free ammonia compared to the digestion with poultry litter alone. The maximum specific methane and gas volumes (197 and 314 mL (g initial VS)-1, respectively) were achieved at 50% VS wheat straw of 5% TS. It was estimated that the inhibitory threshold of free ammonia concentration was about 289 mg L?1. After this concentration, a great reduction of methanogenic activity occurred (at least 54%). A novel general Gompertz model for bacterial growth was developed in this study based on a defined specific bacterial growth rate. The developed model for bacterial growth was further extended to account for bio-products and substrate consumption by means of corresponding yield coefficients. All the models developed herein could meet the initial conditions of bacterial growth, bio-products, and substrate consumption. Batch experiments of anaerobic co-digestions of poultry litter and wheat straw at 2% total solids level consisting of 100, 75, and 50%VS of poultry litter were conducted to verify the model. The maximum methane volumes and specific methane yields were obtained (1699 mL and 207 mL (g initial VS)?1 for 50% co-digestion, 1016 mL and 134 mL (g initial VS)-1) for 75%, and 35.8 mL and 5.18 mL (g initial VS)?1) for 100%). The lowest methane volume of 100% VS of poultry litter could be attributed to its lowest C:N ratio (9.63) and highest pH value (7.71). Volatile solid removals by 46.2, 54.4, and 53.3% were achieved by 100, 75, and 50%VS of poultry litter co-digestions, respectively. The developed models for bio-products were successfully applied to cumulative methane volumes produced from anaerobic co-digestion.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: 1. Shen, J., J. Zhu. 2015. Determination of Kinetic Parameters in Methane Production of Anaerobic Co-Digestion from Methane Volume and COD Balance. ASABE Annual International Meeting paper#: 2187873, New Orleans, LA. July 26-29, 2015.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: 2. Shen, J., J. Zhu. 2015. Optimization of Methane Production in Anaerobic Co-Digestion at different Solid Concentrations and ratios of Poultry Litter to Wheat Straw using a Developed Statistical Model. ASABE Annual International Meeting paper#: 2187836, New Orleans, LA. July 26-29, 2015.


Progress 06/10/14 to 09/30/14

Outputs
Target Audience: The target audiences for this project are poultry producers, agricultural consultants, agricultural environmental engineers, renewable energy industries, local and state environmental regulatory agencies, and the general public with interest in protecting the environment from pollution by agricultural productions and promoting "green" energy and operations. Efforts are expended in reaching out to these audiences, which is ongoing. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? This project has provided professional training to a post-doctorate trainee, and will provide training opportunities to graduate students down the road as well. With more research based information to be generated from this project and made available, publications and other training opportunities for poultry producers and agricultural professionals will be developed and made available. It is also expected that the information obtained from this project will be used as course materials in classroom teaching so undergrad students will gain training opportunities as well in preparing them to meet the challenges of future poultry production in a sustainable world. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? We will continue the current overarching project (poultry litter treatment and reuse technologies development) and work on the sub-objectives listed in the project one by one between now and the next reporting period. Hopefully, we will generate substantial results by the time for the next report.

Impacts
What was accomplished under these goals? At this moment, the experimental setup for investigating objectives listed under the first overaching objective, i.e., "Poultry litter treatment and reuse technologies development", was completed, with preliminary experiments to understand the digestibility of poultry litter initiated. Poultry litter was collected from the poultry production farm located in Savoy, Arkansas (the University of Arkansas Poultry Research Facility), and was used as the feedstock for anaerobic digestion. The litter was characterized for its chemical composition including nutrients and biochemical properties. Trials with different content of poultry litter in liquid anaerobic digestion were under way, and still are ongoing. It is hoped that the data from these preliminary trials will provide key information on developing special anaerobic digestion techniques to treat dry poultry litter to produce biogas and reduce the volume of litter needing to be disposed of. Since the project only started in June with a new post doctorate associate hired in August, 2014, it is expected that more information will be generated between now and the next reporting period, and will be presented in the next report.

Publications