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1. Quantifying the Potential of Renewable Natural Gas to Support a Reformed Energy Landscape: Estimates for New York State

   https://doi.org/10.3390/en14133834  

   Taboada, Stephanie; Clark, Lori; Lindberg, Jake; Tonjes, David J; Mahajan, Devinder (July 2021, Energies)

   null (Ed.)

   Public attention to climate change challenges our locked-in fossil fuel-dependent energy sector. Natural gas is replacing other fossil fuels in our energy mix. One way to reduce the greenhouse gas (GHG) impact of fossil natural gas is to replace it with renewable natural gas (RNG). The benefits of utilizing RNG are that it has no climate change impact when combusted and utilized in the same applications as fossil natural gas. RNG can be injected into the gas grid, used as a transportation fuel, or used for heating and electricity generation. Less common applications include utilizing RNG to produce chemicals, such as methanol, dimethyl ether, and ammonia. The GHG impact should be quantified before committing to RNG. This study quantifies the potential production of biogas (i.e., the precursor to RNG) and RNG from agricultural and waste sources in New York State (NYS). It is unique because it is the first study to provide this analysis. The results showed that only about 10% of the state’s resources are used to generate biogas, of which a small fraction is processed to RNG on the only two operational RNG facilities in the state. The impact of incorporating a second renewable substitute for fossil natural gas, “green” hydrogen, is also analyzed. It revealed that injecting RNG and “green” hydrogen gas into the pipeline system can reduce up to 20% of the state’s carbon emissions resulting from fossil natural gas usage, which is a significant GHG reduction. Policy analysis for NYS shows that several state and federal policies support RNG production. However, the value of RNG can be increased 10-fold by applying a similar incentive policy to California’s Low Carbon Fuel Standard (LCFS). 

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2. Integrating dairy manure for enhanced resource recovery at a WRRF: Environmental life cycle and pilot‐scale analyses

   https://doi.org/10.1002/wer.1574  

   Bryant, Casey; Coats, Erik R. (April 2021, Water Environment Research)

   Abstract The Twin Falls, Idaho wastewater treatment plant (WWTP), currently operates solely to achieve regulatory permit compliance. Research was conducted to evaluate conversion of the WWTP to a water resource recovery facility (WRRF) and to assess the WRRF environmental sustainability; process configurations were evaluated to produce five resources—reclaimed water, biosolids, struvite, biogas, and bioplastics (polyhydroxyalkanoates, PHA). PHA production occurred using fermented dairy manure. State‐of‐the‐art biokinetic modeling, performed using Dynamita's SUMO process model, was coupled with environmental life cycle assessment to quantify environmental sustainability. Results indicate that electricity production via combined heat and power (CHP) was most important in achieving environmental sustainability; energy offset ranged from 43% to 60%, thereby reducing demand for external fossil fuel‐based energy. While struvite production helps maintain a resilient enhanced biological phosphorus removal (EBPR) process, MgO₂production exhibits negative environmental impacts; integration with CHP negates the adverse consequences. Integrating dairy manure to produce bioplastics diversifies the resource recovery portfolio while maintaining WRRF environmental sustainability; pilot‐scale evaluations demonstrated that WRRF effluent quality was not affected by the addition of effluent from PHA production. Collectively, results show that a WRRF integrating dairy manure can yield a diverse portfolio of products while operating in an environmentally sustainable manner. Practitioner pointsWastewater carbon recovery via anaerobic digestion with combined heat/power production significantly reduces water resource recovery facility (WRRF) environmental emissions.Wastewater phosphorus recovery is of value; however, struvite production exhibits negative environmental impacts due to MgO₂production emissions.Bioplastics production on imported organic‐rich agri‐food waste can diversify the WRRF portfolio.Dairy manure can be successfully integrated into a WRRF for bioplastics production without compromising WRRF performance.Diversifying the WRRF products portfolio is a strategy to maximize resource recovery from wastewater while concurrently achieving environmental sustainability. 

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3. Creating a Circular Nitrogen Bioeconomy in Agricultural Systems through Nutrient Recovery and Upcycling by Microalgae and Duckweed: Past Efforts and Future Trends

   https://doi.org/10.13031/ja.14891  

   Femeena, Pandara Valappil; House, Gregory R.; Brennan, Rachel A. (January 2022, Journal of the ASABE)

   Highlights Aquatic vegetation-based nutrient recovery offers an alternate approach for treating agricultural wastewater. Microalgae and duckweed can upcycle waste nutrients into valuable bio-based products. Producing feed, fertilizer, and fuel from manure-grown aquatic vegetation promotes a circular N-bioeconomy. Abstract . The massive amounts of nutrients that are currently released into the environment as waste have the potential to be recovered and transformed from a liability into an asset through photosynthesis, industry insight, and ecologically informed engineering design aimed at circularity. Fast-growing aquatic plant-like vegetation such as microalgae and duckweed have the capacity to enable local communities to simultaneously treat their own polluted water and retain nutrients that underlie the productivity of modern agriculture. Not only are they highly effective at upcycling waste nutrients into protein-rich biomass, microalgae and duckweed also offer excellent opportunities to substitute or complement conventional synthetic fertilizers, feedstocks in biorefineries, and livestock feed while simultaneously reducing the energy consumption and greenhouse gas emissions that would otherwise be required for their production and transport to farms. Integrated systems growing microalgae or duckweed on manure or agricultural runoff, and subsequent reuse of the harvested biomass to produce animal feed, soil amendments, and biofuels, present a sustainable approach to advancing circularity in agricultural systems. This article provides a review of past efforts toward advancing the circular nitrogen bioeconomy using microalgae- and duckweed-based technologies to treat, recover, and upcycle nutrients from agricultural waste. The majority of the work with microalgae- and duckweed-based wastewater treatment has been concentrated on municipal and industrial effluents, with <50% of studies focusing on agricultural wastewater. In terms of scale, more than 91% of the microalgae-based studies and 58% of the duckweed-based studies were conducted at laboratory-scale. While the range of nutrient removals achieved using these technologies depends on various factors such as species, light, and media concentrations, 65% to 100% of total N, 82% to 100% of total P, 98% to 100% of NO3-, and 96% to 100% of NH3/NH4+ can be removed by treating wastewater with microalgae. For duckweed, removals of 75% to 98% total N, 81% to 93% total P, 72% to 98% NH3/NH4+, and 57% to 92% NO3- have been reported. Operating conditions such as hydraulic retention time, pH, temperature, and the presence of toxic nutrient levels and competing species in the media should be given due consideration when designing these systems to yield optimum benefits. In addition to in-depth studies and scientific advancements, policies encouraging supply chain development, market penetration, and consumer acceptance of these technologies are vitally needed to overcome challenges and to yield substantial socio-economic and environmental benefits from microalgae- and duckweed-based agricultural wastewater treatment. Keywords: Circular bioeconomy, Duckweed, Manure treatment, Microalgae, Nitrogen, Nutrient recycling, Wastewater treatment. 

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4. Cycling Phosphorus and Nitrogen through Cropping Systems in an Intensive Dairy Production Region

   https://doi.org/10.3390/agronomy11051005  

   Leytem, April B.; Williams, Paula; Zuidema, Shan; Martinez, Audrey; Chong, Yen Leng; Vincent, Alyssa; Vincent, Aaron; Cronan, Daniel; Kliskey, Andrew; Wulfhorst, J. D.; et al (May 2021, Agronomy)

   null (Ed.)

   As pressure on the dairy industry to reduce its environmental impact increases, efficient recycling of manure nutrients through local cropping systems becomes crucial. The aim of this study was to calculate annual nitrogen (N) and phosphorus (P) budgets in six counties located in the Magic Valley, Idaho and estimate what distance manure would need to be transported to be in balance with crop nutrient demand given current dairy cattle populations and cropping systems. Our analysis suggests that crop N needs will not be met solely by manure, and synthetic fertilizer will need to be applied. However, to balance P with crop production, manure would need to be transported a minimum of 12.9 km from dairies and would have to replace synthetic fertilizer P on 91% of regional cropland. Education of producers and technical specialists would be necessary to improve the management of manure use in regional cropping systems. Technical solutions such as alternative diets for cattle and nutrient capture from manure streams will also likely be necessary to bring regional P into balance to protect environmental quality and improve the sustainability of the regional dairy industry. 

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5. Board 330: Iron Range Engineering Academic Scholarships for Co-Op Based Engineering Education

   Spence, Catherine M. Siverling (June 2023, Review directory American Society for Engineering Education)

   This project will contribute to the national need for well-educated scientists, mathematicians, engineers, and technicians by supporting the retention and graduation of high-achieving, low-income students with demonstrated financial need at Minnesota State University, Mankato. Over its six year duration, this project will fund scholarships to 120 unique full-time students who are pursuing Bachelor of Science degrees in engineering. First semester junior, primarily transfer, students at Iron Range Engineering will receive scholarships for one semester. The Iron Range Engineering (IRE) STEM Scholars Program provides a financially sustainable pathway for students across the nation to graduate with an engineering degree and up to two years of industry experience. Students typically complete their first two years of engineering coursework at community colleges across the country. Students then join IRE and spend one transitional semester gaining training and experience to equip them with the technical, design, and professional skills needed to succeed in the engineering workforce. During the last two years of their education, IRE students work in industry, earning an engineering intern salary, while being supported in their technical and professional development by professors, learning facilitators, and their own peers. The IRE STEM Scholars project will provide access to a financially responsible engineering degree for low-income students by financially supporting them during the transitional semester, which has two financial challenges: university tuition costs are higher than their previous community college costs, and the semester occurs before they are able to earn an engineering co-op income. In addition, the project will provide personalized mentorship throughout students’ pathway to graduation, such as weekly conversations with a mentor. By providing these supports, the IRE STEM Scholars project aims to prepare students to be competitive applicants for the engineering workforce with career development and engineering co-op experience. Because community colleges draw relatively representative proportions of students from a variety of backgrounds, this project has the potential to learn how transfer pathways and co-op education can support financially sustainable pathways to engineering degrees for a more diverse group of students and contribute to the development of a diverse, competitive engineering workforce. The overall goal of this project is to increase STEM degree completion of low-income, high-achieving undergraduates with demonstrated financial need. As part of the scope of this project, a concurrent mixed-methods research study will be done on engineering students’ thriving, specifically their identity, belonging, motivation, and overall wellbeing (or mental and physical health). Student outcomes have previously been measured primarily through academic markers such as graduation rates and GPA. In addition to these outcomes, this project explores ways to better support overall student thriving. This study will address the following research questions: How do undergraduate students’ engineering identity and belongingness develop over time in a co-op-based engineering program? How do undergraduate students’ motivation and identity connect to overall wellbeing in a co-op-based engineering program? In the first year of the IRE STEM Scholars Project, initial interview data describe scholars’ sense of belonging in engineering, prior to their first co-op experiences and survey data describe IRE students’ experiences in co-op and overall sense of belonging. Future work will utilize these values to identify ways to better support the IRE STEM scholars’ identity development as they move into their first co-op experiences. This project is funded by NSF’s Scholarships in Science, Technology, Engineering, and Mathematics program, which seeks to increase the number of low-income academically talented students with demonstrated financial need who earn degrees in STEM fields. It also aims to improve the education of future STEM workers, and to generate knowledge about academic success, retention, transfer, graduation, and academic/career pathways of low-income students. 

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