Reengineering Biological Treatment of Manure for Mitigating Ammonia Emissions from Livestock Operations

REENGINEERING BIOLOGICAL TREATMENT OF MANURE FOR MITIGATING AMMONIA EMISSIONS FROM LIVESTOCK OPERATIONS

Sponsoring Institution

National Institute of Food and Agriculture

Project Status

COMPLETE

Funding Source

HATCH

Reporting Frequency

Annual

Accession No.

1005754

Grant No.

(N/A)

Cumulative Award Amt.

(N/A)

Proposal No.

(N/A)

Multistate No.

(N/A)

Project Start Date

Jan 21, 2015

Project End Date

Mar 31, 2019

Grant Year

(N/A)

Program Code

[(N/A)]- (N/A)

Project Director
Ndegwa, P.

Recipient Organization
WASHINGTON STATE UNIVERSITY
240 FRENCH ADMINISTRATION BLDG
PULLMAN,WA 99164-0001

Performing Department
Biological Systems Engineering

Non Technical Summary
Besides recovery of nitrogen (N) from livestock manure for fertilizer, nitrification-denitrification bioprocess offers the most environmentally-friendly approach of disposing of N via benign nitrogen gas (N2). This process, however, faces multiple drawbacks, including: (i) extremely slow nitrification step, (ii) vulnerability of nitrifying organisms to high N loads (high-strength wastewaters), and (iii) requirement for separate aerobic and anaerobic regimes either in space or time. Consequently, this process demands large reactors and thus more capital and operation costs, is unsuitable for treatment of high-strength livestock wastewaters, and multiple reactors or complicated control systems are required to provide aerobic and anaerobic regimes. In this project, we propose a novel bioprocess that overcomes these well-known challenges, using a heterotrophic micro-organism (Alcaligenes faecalis No. 4) with the unique ability toremove N in wastewaters via N2 and microbial uptake in one fast aerobic process. The central hypothesize of our research proposal is that "the conventional pathway of ammonium N removal via N2 in two steps: (i) aerobic autotrophic nitrification, and (ii) anaerobic heterotrophic denitrification can be significantly simplified and shortened using this unique strain of aerobic heterotroph. To test our central hypothesis, our research plan will address four specific objectives. The first objective will evaluate treatment efficacy of our previously isolated Alcaligenes faecalis No. 4 on dairy wastewater in batch-fed reactors. The second objective will determine optimum environmental parameters and wastewater characteristics for this process. The third objective will optimize the process in continuous flow bioreactors, while the fourth objective will assess achievable mitigations of ammonia, greenhouse gases, and odor emissions during post-treatment storage of treated effluents. Besides mitigation of ammonia emissions, the treatment system proposed in this project also offers several other benefits, including: (i) significant mitigation of odor and gaseous emissions, (ii) savings of initial capital and operational investments, and (iii) significant reduction in livestock operations footprints.

Animal Health Component

30%

Research Effort Categories

Basic

70%

Applied

30%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
133	0410	2020	25%
141	0410	2020	20%
302	0199	2020	20%
307	0410	2020	20%
402	0199	2020	15%

Knowledge Area
302 - Nutrient Utilization in Animals; 133 - Pollution Prevention and Mitigation; 141 - Air Resource Protection and Management; 307 - Animal Management Systems; 402 - Engineering Systems and Equipment;

Subject Of Investigation
0199 - Soil and land, general; 0410 - Air;

Field Of Science
2020 - Engineering;

Keywords

Goals / Objectives
Thelong-term goal of our researchis to develop technologies to control odor, gaseous, and particulate matter emissions from livestock wastewaters. In this project, we propose a novel biological treatment process for mitigation of primarily ammonia discharge and also (secondary) release of odor and greenhouse gases from livestock waste. We hypothesize that the conventional pathway of ammonium N removal via N2 in two steps: (i) aerobic autotrophic nitrification (NH4 + →NH2OH→NO2-→NO3-), and (ii) anaerobic heterotrophic denitrification (NO3 - →NO2 - →NO→N2O→N2) can be significantly simplified and shortened using unique strains of aerobic heterotrophs through the pathway: NH4+ → NH2OH →N2. Wehave identified such a heterotrophic micro-organism (Alcaligenes faecalis No. 4) with this remarkable ability to consume carbon and remove ammoniacal nitrogen from swine wastewater mainly via N2 gas and microbial assimilation in a single aerobic process.This innovative bioprocess, in a single-stroke, overcomes most of the drawbacks of the conventional nitrification-denitrification process noted in the previous paragraph. To test our central hypothesis, our research plan will address four specific objectives. The first objective is to evaluate treatment efficacy of our previously isolated Alcaligenes faecalis No. 4 on dairy wastewater in batch reactors. The second objective is to determine optimum environmental parameters (temperature, oxygen level or aerobiosis) and wastewater characteristics (ammoniacal N and organic C loads) for this process. The third objective is to optimize the process in continuous flow bioreactors, while the fourth objective will evaluate potential mitigation of ammonia, odor, and greenhouse gases emissions during post-treatment storage.

Project Methods
To achieve the overall goal of this project, our experimental plan consists of four specific objectives. The first objective is to evaluate treatment efficacy of Alcaligenes faecalis No. 4 on dairy wastewater in batch reactors. The second objective is to determine optimum environmental parameters and wastewater characteristics for this process. The third objective is to optimize the process in continuous flow bioreactors, while the fourth objective will evaluate potential mitigation of ammonia, odor, and greenhouse gases emissions during post-treatment storage.Objective #1: Evaluate treatment efficacy of Alcaligenes faecalis No. 4 on dairy wastewater: To determine the efficacy of strain No. 4 intwo dairy wastewater streams, aerated batch experiments will be conducted. In these experiments, 18 mL of the pre-culture (5% inoculum) will be ejected into 360 mL of either MS or RM in 500-mL conical flasks and stirred with magnetic stirrers at 200 rpm. First, this organism's cultivation will be performed under sterilized conditions to evaluate its viability without interference from indigenous microorganisms. Second, the organism will then be cultivated in non-sterilized conditions to evaluate its efficacy under field conditions. Data obtained in these series of batch experiments will be used to assess changes in concentration of TAN over time, nitrification and denitrification characteristics of A. faecalis No. 4 in dairy wastewater, and intracellular accumulation of nitrogen in this organism. The nitrogen mass balance will be used to corroborate the TAN removal mechanism.Objective #2: To determine optimum environmental parameters (temperature, aeration level, and pH) and wastewater characteristics (TAN and C/N ratio) for this treatment process: Two sets of batch-fed mode experiments will be performed to achieve this objective. First, the effect of environmental conditions (pH: 6-9; temperatures: 10-40°C; and aeration levels: 0.5-6.0 mg L-1), on treatment, will be evaluated for raw dairy manure with an adjusted TAN of 2,000 mg L-1. Second, the effect of wastewater characteristics (TAN: 400-2,000 mg L-1; and C/N ratio: 5-10) will be determined in subsequent series of batch-fed mode experiments, at best or optimum environmental conditions established in the first set of batch-fed experiments. Liquid samples will be taken periodically for chemical analysis (TAN, NH2OH, NO2-, NO3-, COD, MLVSS, VS, pH, etc.) and microbial growth. Data from these tests will also be used to determine biokinetic parameters (e.g., specific TAN removal rate, growth yields, etc.) for: running the continuously-fed studies, sizing of reactors, and to appraise the effectiveness of treatments.Objective #3: Determine pertinent engineering parameters and optimize the process in continuous flow reactors: These continuously-fed treatment studies will be conducted in 4 L continuous flow reactors equipped with pH, aeration, and temperature controls. The treatment will be initiated in batch-fed mode for 3 d prior to thestart of continuous-fed mode runs. To obtain preliminary baseline data for our system, the continuous reactors will initially be run using the optimum environmental conditions and wastewater characteristics established in the previous objective 4.2 to evaluate pertinent engineering parameters (HRT: 4-48 h; SRT: 2-8 d; and TAN loading rate: 10-100 mg L-1 h-1). The kinetics of ammonia removal for optimized continuous flow will be determined, at steady state operating conditions, to provide basic information required for sizing and operating full-scale reactors for this bioprocess.Objective #4: Evaluate emissions gaseous (NH3, CO2, CH4, and N2O) before and after the bio-treatment in simulated storages of treated and untreated dairy manure: The potential mitigation of gaseous emissions will be evaluated from storages of treated and non-treated dairy manure using methods and protocols previously developed in our laboratory (Vaddella et al., 2011; Vaddella et al., 2010; Ndegwa et al., 2009). Briefly, storages of treated and non-treated dairy wastewater will be simulated under laboratory conditions for a period ranging from 21-42 d. Concentrations of NH3 and greenhouse gases (CO2, CH4, and N2O), in the vent air from the headspace of storages, will be measured continuously using a photoacoustic IR multigas analyzer (Model 1412, Innova AirTech Instruments, Ballerup, Denmark). Emissions will be determined from the respective gas concentrations and constant vent airflow rate. Samples of stored effluent will be taken periodically for determination of volatile fatty acids, which are indicators of potential odor generation. Data collected will reveal the potential levels of mitigations of gaseous and odor emissions during storage of process effluents.Analytical Methods and Data AnalysesTotal solids, COD, VS, MLVSS, and TN will be determined from raw samples using standard methods (APHA, 2005). Samples will, however be, centrifuged at 10,000 rpm and the supernatants passed through 0.2 mm membrane filters to measure the concentration of TAN, NO2-, and NO3- using standard methods (APHA, 2005) while NH2OH concentrations will be analyzed spectrophotometerically (Joo et al, 2005; Frear and Burrell, 1955). The volatile fatty acids (VFAs) will be determined using Hach Method 8196 (Hach Company Inc., 1993).Total viable cell numbers in RM or MS expressed as colony-forming units (cfu) will be conducted on LB agar plates to detect common heterotrophic bacteria. The LB agar (pH 7.0) medium consists of 1% peptone, 0.5% NaCl, 0.5% yeast extract and 1.5% agar. The viable cell numbers of strain No. 4 will also be estimated using LB agar plating because, compared to other bacteria, the colonies of strain No. 4 appear much sooner and has significantly different appearance.Intracellular nitrogen in dry biomass will be determined with an elemental analyzer (LECO TrueSpec Macro CHNS Elemental Analyzer, St. Joseph, MI). Intracellular nitrogen content (mg-N/L) will be calculated from the viable cell number and the nitrogen content (%) obtained from the elemental analysis of dry cells. Dry cells will be obtained by centrifugation of culture broth at 10,000 rpm, followed by washing with sterilized water and drying at 105°C for 24 h.The content of NH3 and NO in the exhaust gases, during continuously-fed experiments, will be determined using a chemiluminescence nitrogen oxides-ammonia analyzer (Model 17C, Thermo Environmental Instruments, Inc., Mountain View, CA). A gas-tight syringe will be used to periodically collect gas samples (50 μL), from exhaust air, for determination of N2O, N2, and O2 using a Varian CP-3800 GC (Varian, Walton-on Thames, UK) equipped with ECD.The process kinetics, in batch-fed experiments, will be analyzed using Monod type equation described in equation 4 for nitrification process.QN = qN,max × STAN/(KN + STAN) [4]where: qN = specific nitrification rate (g[TAN] g-1[MLVSS] d-1); qN, max is the maximum nitrification rate (g[TAN] g-1[MLVSS] d-1); STAN concentration of TAN (mg L-1); KN is half saturation constant for TAN (mg L-1); and MLVSS is the measure of the nitrifying biomass.For continuously fed treatment operating at steady state conditions, the specific substrate rate is proportional to substrate concentration (first-order kinetics). Substrate removal rate constant k is obtained from a plot of specific substrate removal rate versus the concentration of substrate in the effluent.The impact of temperature on nitrification will be modeled using the traditional van't Hoff-Arrhenius described in equation 5 below (Tchobanoglous and Burton, 1991).qN = qN,20 × ?(T-20) [5]where: qN,20 is specific nitrification rate (g[TAN] g-1[MLVSS] d-1) at 20°C; T is temperature (°C); and ? is a dimensionless temperature coefficient.

Progress 01/21/15 to 03/31/19

Outputs
Target Audience:Dairy producers, scientific community, environmental regulators and activists, staff of NRCS and Conservation Districts, State and Country extension personnel, andcitizens. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Graduate students, postdoctoral fellows, and visiting scholars were either involved and/or trained in this project during this reporting period. How have the results been disseminated to communities of interest?The results have been disseminated to communities of interest accordingly viapublished factsheets, bulletins, field demonstrations, field days, and producer meetings. This final report presents some of these dissemination tools in the products section as in other products section. Extensive report of dissemination activities and products have also been presented inrespectiveprogress reports in 2016, 2017, and 2018, which should be read together with this final report. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Accomplishments areall captured in the products and also inour submittedprogress reports of2016, 2017, and 2018.

Publications

Type: Journal Articles Status: Other Year Published: 2019 Citation: Zeb, I., G.K. Kafle, X. Xue, P.M. Ndegwa. 2019. Enhanced biogas yield in anaerobic sequencing batch reactors using a cationic polymer.
Type: Journal Articles Status: Submitted Year Published: 2019 Citation: 1. S.S. Coulibaly, P.M. Ndegwa, S.Y. Soro, S. Kon�, A.E. Kouam�, I. A. Bi Zoro. 2019. Vermicompost application rate and timing for optimum productivity of onion (Allium cepa). Journal of Soil Science and Plant Nutrition.
Type: Journal Articles Status: Published Year Published: 2019 Citation: D Wang, Y Xin, H Shi, P Ai, L Yu, X Li, S Chen, Closing ammonia loop in efficient biogas production: Recycling ammonia pretreatment of wheat straw, Biosystems Engineering 180, 182-190
Type: Journal Articles Status: Awaiting Publication Year Published: 2019 Citation: Yao, Y. S. Chen, in press. Enhanced performance of anaerobic digestion with metal ions contained in soil. Journal of Cleaner Production.
Type: Journal Articles Status: Accepted Year Published: 2019 Citation: J Ma, S Xie, L Yu, Y Zhen, Q Zhao, C Frear, S Chen, Z Wang, Z Shi. In press. pH Shaped Kinetic Characteristics and Microbial Community of Food Waste Hydrolysis and Acidification. Biochemical Engineering Journal. Accepted 3/3/2019
Type: Book Chapters Status: Published Year Published: 2019 Citation: Michaels, E., Yorgey, G.G., C.E. Kruger, and Thiers, P. Resubmitted after revision. Legislative, socio-economic and technical constraints to the use of recovered mineral nutrients: US Livestock Nutrient Management Policy Framework. In Meers and Velthof, eds. Nutricover: The Recovery and Use of Mineral Nutrients from Organic Residues. Wiley.
Type: Other Status: Published Year Published: 2019 Citation: Yorgey, G., C. Frear, N. Kennedy, and C. Kruger. 2019. The dairy manure biorefinery. Washington State University Extension Publication FS316E (peer reviewed), Pullman, WA.

Progress 10/01/17 to 09/30/18

Outputs
Target Audience:Dairy producers, scientific community, environmental regulators and activists, staff of NRCS and Conservation Districts, State and Country extension personnel, and the wide public/citizens. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Graduate students,postdoctoral fellows, andvisiting scholars were either involved and/or trained in this project during this reporting period. How have the results been disseminated to communities of interest?Held five field demonstrations and trainingsto disseminate results andfindings from thisproject's work. What do you plan to do during the next reporting period to accomplish the goals?Research will continue along the same themes. We will thus pursue extramural funding and recruit additional graduate students and other type of scholars /researchers in order to continue advancing the objectives outlined in our project.

Impacts
What was accomplished under these goals? Alcaligenes faecalis strain No. 4 is a heterotrophic aerobic microorganism with the ability of converting ammonium nitrogen to both dinitrogen gas (N2) and microbial biomass, indicating the strain's high potential in the bio-removal of ammonia from wastewater. The efficacy of ammonia removal, from dairy wastewater, using a heterotrophic bacteria A. faecalis strain No. 4 was investigated in one of the studies of this project. Preliminary optimization data with respect to four pertinent parameters (temperature, carbon-to-nitrogen ratio, initial TAN concentration, and oxygenation level) governing this bacteria performance at removing ammonia are summarized here. The optimal conditions were as follows: temperature of 30°C; carbon to nitrogen ratio of 5; initial total ammonia concentration of 1200 mg/L; and oxygen supply for 20 min at a constant rate of 0.2 L min-1 every 4 h. Under these laboratory conditions, nearly total ammonia nitrogen removal from dairy wastewater (i.e. approximately 100%) was achieved in 20 h. Similar operational conditions with air supplying the oxygen, however, achieved ammonia degradation of only approximately 80%. This study moves this technology closer to industrial application. Future research is will focus on verifying these performances at pilot and subsequently at full-scale dairy operations. The dynamics of microbial communities during anaerobic digestion for different states of acclimation and inhibitions is key to improving methane production. We conducted a study to investigate the dynamics of methane producing communities subjected to ammonia and salinity stresses during batch anaerobic digestion, of dairy wastewater, in both acclimated and unacclimated conditions. Previous studies mostly focused on concentrations thresholds for inhibition and adaptation. Experimental data was fitted into the 'Modified Gompertz Model' and resulting lag phase values were related to stress conditions. Irrespective of acclimation conditions, digesters subjected to ammonia stresses produced less methane compared to those subjected to salinity stresses. Petrimonas and Clostridium XI were the most dominant bacterial genera in salinity-acclimated digesters, whereas, Petrimonas, Clostridium XI, Alkaliflexus, sedimentibacter, and Clostridium III were the most abundant bacterial genera in salinity-unacclimated digesters. In ammonia-acclimated digesters, Petrimonas, Clostridium XI, and Alkaliflexus were the most dominant genera. Whereas, Petrimonas, Clostridium XI, Alkaliflexus, sedimentibacter, Clostridium III, Clostridium XIVa, were the most abundant bacterial genera in TAN-unacclimated digesters. Methanosarcina, Methanobrevibacter and Methanobacterium were most abundant archaea in both salinity and ammonia stressed digesters. The principal component analysis showed clustering of bacteria between the acclimated and the unacclimated digesters; such clustering of archaea was not evident. This information is pertinent in the operation and reclamation of sour anaerobic digesters.

Publications

Type: Journal Articles Status: Submitted Year Published: 2018 Citation: Iftikhar, Z, J. Ma, Q. Zhao, F. Mehboob, G.K. Kafle, A. Yaqub, R. Nazir, P. Ndegwa, C. Frear. 2018. Kinetic and microbial analysis of methane production from dairy wastewater anaerobic digester under ammonia and salinity stresses. Submitted to Journal of Cleaner Production.
Type: Journal Articles Status: Submitted Year Published: 2018 Citation: Coulibaly, S.S., P.M. Ndegwa, M. Ayiania, B.I.A. Zoro. 2018. Growth, reproduction, and life cycle of Eudrilus eugeniae in cocoa and cashew wastes. Submitted to Bioresource Technology.
Type: Journal Articles Status: Published Year Published: 2017 Citation: Yao, Yiqing, Liang Yu, Rishikesh Ghogare, Alexander Dunsmoor, Maryam Davaritouchaee, Shulin Chen, 2017. Simultaneous ammonia stripping and anaerobic digestion for efficient thermophilic conversion of dairy manure at high solids concentration, Energy, 141:179-188.
Type: Journal Articles Status: Published Year Published: 2018 Citation: Yao, Y., L. An, G. K. Kafle, S. Chen., 2018. Role of soil in improving process performance and methane yield of anaerobic digestion with corn straw as substrate. Energy,151:998-1006.
Type: Journal Articles Status: Published Year Published: 2018 Citation: Woodbury, B.L., R.A. Eigenberg, H.G. Minns, P.M. Ndegwa. 2017. Data Analysis Protocol for Using Resistivity Array as an Early-Warning Wastewater Pond Leak Detector. Journal of Environmental and Engineering Geophysics 23(2), 251-260.
Type: Journal Articles Status: Published Year Published: 2018 Citation: Kafle, G.K, H.S. Joo, P.M. Ndegwa. 2017. Sampling duration and frequency for determining emission rates for naturally ventilated dairy barns. Trans. of ASABE 61(2), 681-691.
Type: Other Status: Published Year Published: 2018 Citation: Hall, S., Benedict, C., Harrison, J., and Yorgey, G.G. 2018. Nutrient Recovery Products from Dairy Manure. Washington State University Extension Publication, Pullman, WA.
Type: Other Status: Published Year Published: 2018 Citation: Frear, C.S., Ma, J., and G.G. Yorgey. 2018. Approaches to nutrient recovery from dairy manure. Washington State University Extension Publication EM112E, Pullman, WA.
Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Jensen, J., C.S. Frear, C.E. Kruger, and G.G. Yorgey. 2018. Completing a successful feasibility study for an anaerobic digestion project. Washington State University Extension Publication FS292E, Pullman, WA.
Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Yorgey, G.G., Ewing, T., Frear, C., Saleh, A., Kannan, N., and Yu, L. 2018. Technologies for Dairy Nutrient Recovery: Evaluation of Low-impact Ammonia Stripping with Bio-Fertilizer Recovery and Support for Technology Decision Making. Water Environment Research Foundation National research Center for Resource Recovery and Nutrient Management. Alexandria, VA. August 7, 2018.
Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Yorgey, G.G. 2018. Resource Recovery from Dairies. Presentation to Au Sable Institute. Mount Vernon, WA, July 25, 2018.
Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Yorgey, G.G. 2018. Climate and Resource Recovery Update. Presentation to CSANR internal and external advisory committees. Ellensburg, WA, February 27, 2018.

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

Outputs
Target Audience:Dairy producers, scientific community, environmental regulators and activists, staff of NRCS and Conservation Districts, State and Country extension personnel, and the wide public/citizens. Changes/Problems:Two Hatch projects (#0630 and #0554) were consolidated during this reporting period. This annual report represents consolidated reports of three faculty members (Pius Ndegwa, Shulin Chen, & Chad Kruger) following termination of a previous Hatch project (#0554 - Advancing Anaerobic Digestion Technology for New Applications involving Shulin Chen and Chad Kruger) in 2016. What opportunities for training and professional development has the project provided?Two PhD students, one MS student, and two postdoctoral fellows were either involved and/or trained in this project during this reporting period. How have the results been disseminated to communities of interest?Outreach Activities: Adult Contacts (in-person, video or webinar viewers): 5629 Continued work on a USDA NRCS project on manure-derived product use in berry production systems, a USDA Northwest Climate Hub project to estimate the GHG impacts of AD systems in Washington, and a WERF project to evaluate the performance and impacts of ammonia stripping for N recovery from dairy manure. Continued progress towards completion of the AD Systems Series. The series is available at: http://csanr.wsu.edu/anaerobic-digestion-systems/series/ Served on the WSDA Dairy Nutrient Advisory Committee. Organized 2 tours to help WSU researchers improve understanding of issues related to nutrient management and AD systems. Developed a roadmap to prioritize areas of future research. What do you plan to do during the next reporting period to accomplish the goals?Research will continue along the same themes. We will thus pursue extramural funding and recruit additional graduate students and scholars in order to continue advancing the objectives outlined in our consolidated project.

Impacts
What was accomplished under these goals? The research activities during the report period included several major efforts including: Developing an in-situ process for ammonia removal by stripping with biogas.This motivation of the work was to improve the efficiency of energy recovery in digesters for small- and medium-sized dairies in order to make adoption of this technology economically feasible. Inhibition of thermophilic AD due to ammonia accumulation is a major challenge in these systems. Our study showed that inhibition of AD occurred at a threshold level of 10% TS. The results show that simultaneous ammonia stripping helped to overcome ammonia inhibition that occurred in thermophilic AD at the threshold TS. The optimum stripping rate was identified as 1 min L-1 and a maximum methane production of 192.3 L kg-1 VS was achieved. Overall, this approach had the potential to improve the efficiency of dairy manure utilization for methane production. The proposed approach simplifies the system by combining ammonia stripping and thermophilic AD within the same digester, making this process simpler and more cost effective than other reported options. Therefore, for small- and medium-scale dairy digesters that are not economically sustainable, this approach makes it possible to digest manure with a high TS content, improve methane production, and reduce wastewater discharge while recovering nutrients. Because this approach demonstrated satisfactory efficiency in this study, the simultaneous ammonium stripping technique coupled with small- and medium-scale thermophilic AD and high TS can be applied to other nitrogen-rich materials like food scraps, though the technique needs to be optimized for those specific conditions. The results of the research work was summarized in a refereed publication. Developing ammonia recycling-based technology for pretreatment of lignocellulose to enhance biogas production. The goal of this effort is to develop an integrated process for pretreating lignocellulosic biomass to be more easily digested anaerobically, thereby increasing biogas productivity. The novel feature of the process is the use of a recycling strategy for ammonia that is produced on-site by the AD process. In this process, (1) ammonia will be stripped out from the AD effluent of digested dairy manure, (2) the ammonia stream will be used to capture carbon dioxide (CO2) from biogas, and (3) the ammonia will be used to pretreat lignocellulosic material in feedstock (such as manure fibers and crop residues) to enhance their performance during AD. This study demonstrated that most cellulose and hemicellulose in wheat straw can be retained for biogas production after ammonia pretreatment. Low concentration ammonia pretreatment was an effective way to enhance lignin removal and surface area of pretreated wheat straw for improving biogas production and methane yield. Moreover, the increased accessibility of cellulose was more important than lignin removal during pretreatment. Anaerobic digestion of wheat straw pretreated by 0.70% ammonia concentration at 105 degrees C resulted in the highest methane yield (353.8 mL g-1 VS). This study also showed that low concentration ammonia pretreatment and TAD are promising processes for the conversion of biomass to bioenergy, achieving effective utilization of the organic carbon in biomass. Identifying optical sensing based spectral bands for rapid determination of manure nutrient to drive precise manure utilization on agricultural land. Excess manure application can adversely affect water quality, while under-application lowers crop yield potential. Precision application of manure requires information on its nutrients but the existing reliable nutrient determination methods are unsuitable for real-time applications. This project is evaluating the potential of near infrared spectroscopy (NIRS) for determination of nutrients composition of dairy manure, as a first step towards development of a precision manure application system. Manure was collected from different dairy farms to determine effective spectral bands for predicting available nutrients (N and P) in the manure with reference to typical lab methods. Spectral data were processed using multivariate statistical methods to identify nutrient specific key spectral bands necessary to develop a low-cost portable nutrients sensing device. This technology will enable farmers to precisely apply manure in the field at desired agronomic rates. The long-term impacts from commercialization and adoption of NIR sensor based precision manure application will be the improved protection of water quality and crop yield, both of which promote sustainable organic farming. A manuscript has been prepared and submitted for peer review and publication consideration based on this research effort. Developing a practical protocol (with respect to reduced sampling 'time and frequency') of determining ammonia and other emissions from dairy housing without compromising integrity of the measurements. We examined five reduced sampling protocols for determining emission factors from naturally ventilated dairy barns: (1) six sampling events, during even months, each event running continuously for 24 h (144 hourly data points), (2) six sampling events, during odd months, each event running continuously for 24 h (144 hourly data points), (3) six sampling events, during even months, each event running continuously for 7 d (1,008 hourly data points), (4) six sampling events, during odd months, each event running continuously for 7 d (1,008 hourly data points), and (5) 12 sampling events, one event every month, each event running continuously for 24 h (288 hourly data points). These five reduced protocols were evaluated against baseline emission factors obtained from a protocol consisting of 12 sampling events, one event every month, each event running continuously for 7 d (2,016 hourly data points). Emission factors for CO2 and NH3 obtained from all the five reduced sampling schedules had relative biases of less than 20% from respective base emission factors; implying that even the most reduced sampling protocol "the six sampling events per year, each event running continuously for 24 h," would be adequate for determining CO2 and NH3 emission factors. However, for H2S, relative biases of the reduced sampling protocols ranged from 2 to 45% with a 50% chance of emission factors falling outside ±20% of baseline emission factors. This research shows the potential of significantly reducing the cost of conducting such measurement campaigns allowing for inclusion of more facilities, which is critical to accurate estimation of respective emission factors. Similarly, a manuscript has also been prepared and submitted for publication in a peer refereed journal.

Publications

Type: Journal Articles Status: Published Year Published: 2017 Citation: Zeb, I., J. Ma, C. Frear, Q. Zhao, P. Ndegwa, Y. Yao, G.K. Kafle. 2017. Recycling separated liquid-effluent to dilute feedstock in anaerobic digestion of dairy manure. Energy 119, 1144-1151.
Type: Journal Articles Status: Published Year Published: 2017 Citation: Neerackal, G.M., P. M. Ndegwa, H. S. Joo, J. H. Harrison. 2017. Manure-pH management for mitigating ammonia emissions from dairy barns and liquid manure storages. Applied Engineering in Agriculture 33(2), 235-242.
Type: Journal Articles Status: Published Year Published: 2016 Citation: Yao, Y., Liang Yu, Rishikesh Ghogare, Alexander Dunsmoor, Maryam Davaritouchaee, Shulin Chen, Simultaneous ammonia stripping and anaerobic digestion for efficient thermophilic conversion of dairy manure at high solids concentration, Energy. 141, 179-188.
Type: Journal Articles Status: Published Year Published: 2017 Citation: Yorgey, G., S.A. Hall, E. Allen, E.M. Whitefield, N. Embertson, V.P. Jones, B.R. Saari, K. Rajagopalan, G. Roesch-McNally, B. Van Horne, J. Abatzoglou, H.P. Collins, L. Houston, C. Seavert, T. Ewing, and C. Kruger. 2017. Northwest U.S. Agriculture in a Changing Climate: Collaboratively Defined Research and Extension Priorities. Front. Environ. Sci., 31 August 2017 | https://doi.org/10.3389/fenvs.2017.00052.
Type: Other Status: Published Year Published: 2017 Citation: Yorgey, G.G., W.L. Pan, R. Awale, S. Machado, and A. Bary. 2017. Soil Amendments. In Yorgey, G. and C. Kruger, eds. Advances in Dryland Farming in the Inland Pacific Northwest, Washington State University Extension Publication EM108, Pullman, WA.
Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Kafle G., L. Khot, P. Ndegwa, I. Zeb. Near infrared spectroscopy based sensing of dairy manure nutrients under dynamic flow conditions. 2017. ASABE Annual International Conference. ASABE Annual International Conference; Jul 16-19, 2017; Spokane, Washington.
Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Kafle, G., P. Ndegwa, H. Joo. Sampling duration and frequency to obtain credible emission factors for naturally ventilated dairy barns. 2017. American Society of Biological and Agricultural Engineers Annual Conference. ASABE Annual International Conference; Jul 16-19, 2017; Spokane, Washington.
Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Xue, X., G.K. Kafle, P. Ndegwa. 2017. Balancing C/N ratio for mitigating ammonia emissions from dairy manure with A. faecalis strain No. 4. American Society of Biological and Agricultural Engineers Annual Conference. ASABE Annual International Conference; Jul 16-19, 2017; Spokane, Washington.

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

Outputs
Target Audience:Dairy producers, scientific community, environmental regulators and activists, staff of NRCS and Conservation Districts, extension personnel, and wider public. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?One PhD student, one MS student, and one postdoctoral student, who forms the pool for the next generation of livestock waste Researchers and Environmental Managers, were either involved or trained in this project in 2016. How have the results been disseminated to communities of interest?Results disseminated via publications in referred journals and presentations in national and/or international conferences. What do you plan to do during the next reporting period to accomplish the goals?We will pursue extramural funding and recruit additional graduate students in order to continue advancing the objectives outlined in our project.

Impacts
What was accomplished under these goals? The products, outlined above, which emanated from this project indicate the project's accomplishments, in 2016, with respect to mitigation of ammonia and other emissions from livestock operations. First, our research demonstrated innovative approaches to reducing cost of treating manure to curb ammonia emissions from dairy operations using a biological method, a chemical method, and a diet formulation approach. Second, our research developed a fairly low-cost method of determining ammonia concentrations in confined dairy operations.

Publications

Type: Journal Articles Status: Published Year Published: 2016 Citation: Neerackal G., P. Ndegwa, H. S Joo, X. Wang, C. Frear, J. Harrison, M. Beutel. 2016. Potential application of Alcaligenes faecalis strain No. 4 in mitigating ammonia emissions from dairy wastewater. Bioresource Technology.206:36-42.
Type: Journal Articles Status: Published Year Published: 2016 Citation: Chen Y., J. Harrison, P. Ndegwa, D. Wilks, L. Vanwieringen, B. Chalupa, F. Sun. 2016. Case Study: Effect of strategic ration balancing on the efficiency of milk protein production and environmental impact of dairy cows in a commercial herd. Professional Animal Scientist.32:115-133.
Type: Journal Articles Status: Published Year Published: 2016 Citation: Wang, X., P.M. Ndegwa, H.S. Joo, G.M. Neerackal, J.H. Harrison, C.O. St�ckle, H. Liu. 2016. Reliable Low-cost devices for monitoring ammonia concentrations and emissions in naturally ventilated dairy barns. Environmental Pollution 208(B): 571-579.
Type: Journal Articles Status: Published Year Published: 2016 Citation: Khalil, T.M., S.S. Higgins, P.M. Ndegwa, C.S. Frear, C.O. St�ckle. 2016. Assessing the effect of different treatments on decomposition rate of dairy manure. Journal of Environmental Management. 182:230-237.
Type: Journal Articles Status: Accepted Year Published: 2016 Citation: Neerackal G., P. Ndegwa, H. S Joo, J. Harrison. (Accepted). Manure-pH management for mitigating ammonia emissions from dairy barns and liquid manure storages. Applied Engineering in Agriculture.
Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Kafle G., P. Ndegwa, L. Khot. Evaluation of near infrared spectroscopy for rapid sensing of dairy manure nutrients. 2016. ASABE Annual International Conference. ASABE Annual International Confeence; Jul 17-20, 2016; Orlando, Florida.
Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Zeb I., G. Kafle, X. Xue, P. Ndegwa. Modelling ammonia inhibition for anaerobic digestion of dairy manure with acclimated and un-acclimated seed. 2016. 2016 Americal Society of Biological and Agricultural Engineers Annual Conference. ASABE Annual International Conference; Jul 17-20, 2016; Orlando, Florida.
Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Zeb I., J. Ma, C. Frear, P. Ndegwa. Separated-effluent recycling in the anaerobic digestion process: effects of ammonia and salinity. 2016. 2016 American Society of Biological and Agricultural Engineers Annual Conference. ASABE 2016 Annual Conference; Jul 17-20, 2016; Orlando, Florida.

Progress 01/21/15 to 09/30/15

Outputs
Target Audience:Dairy producers, environmental regulators, scientific community, graduate student, and citizens Changes/Problems:We have expanded the scope of the project to include other potential technologies for mitigating all air emissions from dairy operations and land application of animal manure. What opportunities for training and professional development has the project provided?Provided training for one PhD students, one MS student, and one postdoctoral fellow in 2015. How have the results been disseminated to communities of interest?Results were published in peer refereed journals and also presented at regional and national commodity and professionals meetings and conferences. What do you plan to do during the next reporting period to accomplish the goals?Will continue with research to accomplish other goals and in the dissemination of new results.

Impacts
What was accomplished under these goals? Research results have been published in peer refereed journals, presented in professional conferences (for scientific community), and also in other non-professional meetings (for other stakeholders including: dairy producers, regulators, citizens, etc.).

Publications

Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Neerackal,G.M., H.S. Joo, X. Wang, P.M. Ndegwa. 2015. Enhanced Biological Treatment for Mitigating Ammonia and Odor Emissions from Dairy Wastewaters. ASABE Annual International Conference. Paper number 152186218; New Orleans, Louisiana, July 26 - July 29.
Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Neerackal, G.M., H.S. Joo, P.M. Ndegwa, J.H. Harrison. 2015. Mitigating Ammonia Emissions from Dairy Barns through Manure-pH Management. Proceedings for Waste to Worth 2015 "Advancing Sustainability in Animal Agriculture," March 30 April 3.
Type: Journal Articles Status: Published Year Published: 2015 Citation: Joo, H.S., P.M. Ndegwa, G.M. Neerackal, X. Wang, J.H. Harrison. 2015. Manure Management Practices for Mitigation of Gaseous Emissions from Naturally Ventilated Dairy barns. Proceedings for Waste to Worth 2015 "Advancing Sustainability in Animal Agriculture," March 30 April 3.
Type: Journal Articles Status: Published Year Published: 2015 Citation: Neerackal, G.M., P.M. Ndegwa, H.S. Joo, X. Wang, J.H. Harrison, A.J. Heber, J.-Q. Ni, C. Frear. 2015. Effects of anaerobic digestion and solids separation on ammonia emissions from stored and land applied dairy manure. Water, Air, & Soil Pollution 226(9):301.
Type: Journal Articles Status: Published Year Published: 2015 Citation: Chen, Y., J.H. Harrison, P. Ndegwa, D. Wilks, L. VanWieringen, W. Chalupa, F. Sun. 2015. Case Study: Effect of strategic ration balancing on the efficiency of milk protein production and environmental impact of dairy cows in a commercial herd. The Professional Animal Scientist 32: 1-19.