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This study analyzes the feasibility of using algae cultivated from wastewater effluent to produce a biodiesel feedstock. The goal was to determine if the energy produced was greater than the operational energy consumed without consideration to constructing the system as well as the emissions and economic value associated with the

This study analyzes the feasibility of using algae cultivated from wastewater effluent to produce a biodiesel feedstock. The goal was to determine if the energy produced was greater than the operational energy consumed without consideration to constructing the system as well as the emissions and economic value associated with the process.

Four scenarios were created:
       1) high-lipid, dry extraction.
       2) high-lipid, wet extraction.
       3) low-lipid, dry extraction.
       4) low-lipid, wet extraction.
In all cases, the system required more energy than it produced. In high lipid scenarios, the energy produced is close to the energy consumed, and a positive net energy balance may be achieved with minor improvements in technology or accounting for coproducts. In the low lipid scenarios, the energy balance is too negative to be considered feasible. Therefore the lipid content affects the decision to implement algae cultivation.

The dry extraction and the wet extraction both require some level of mechanical drying and this makes the two methods yield similar results in terms of the energy analysis. Therefore, the extraction method does not dramatically affect the decision for implementing algae-based oil production from an energetic standpoint. The economic value of the oil in both high lipid scenarios results in a net profit despite the negative net energy. Emission calculations resulted in avoiding a significant amount of CO2 for high lipid scenarios but not for the low lipid scenarios. The CO2 avoided does not account for non-lipid biomass, so this number is an underestimation of the final CO2 avoided from the end products.

While the term "CO2 avoided" has been used for this study, it should be noted that this CO2 would be emitted upon use as a fuel source. These emissions, however, are not “new” CO2 because it has already been emitted and is being captured and recycled. Currently, literature is very divisive on the lipid content present in algae and this study shows that lipid content has a tremendous affect on energy and emissions impacts. The type of algae that can grow in wastewater effluent also should be investigated as well as the conditions that promote high lipid accumulation. The dewatering phase must be improved as it is extremely energy intensive and dominates the operational energy balance.

In order to compete, wet extraction must have a much more significant effect on the drying phase and must avoid the use of the human toxicants methanol and chloroform. Additionally, while the construction phase was beyond the scope of this project it may be a critical aspect in determining the feasibility these systems. Future research in this field should focus on lipid production, optimizing the belt dryer or finding a different method of dewatering, and allocating the coproducts.

Created2012-05
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Description
Rapid urbanization in Phoenix, Arizona has increased the nighttime temperature by 5°C (9 °F), and the average daily temperatures by 3.1°C (5.6 °F) (Baker et al 2002). On the macro scale, the energy balance of urban surface paving materials is the main contributor to the phenomenon of the Urban Heat

Rapid urbanization in Phoenix, Arizona has increased the nighttime temperature by 5°C (9 °F), and the average daily temperatures by 3.1°C (5.6 °F) (Baker et al 2002). On the macro scale, the energy balance of urban surface paving materials is the main contributor to the phenomenon of the Urban Heat Island effect (UHI). On the micro scale, it results in a negative effect on the pedestrian thermal comfort environment. In their efforts to revitalize Downtown Phoenix, pedestrian thermal comfort improvements became one of the main aims for City planners. There has been an effort in reformulating City zoning standards and building codes with the goal of developing a pedestrian friendly civic environment. Much of the literature dealing with mitigating UHI effects recommends extensive tree planting as the chief strategy for reducing the UHI and improving outdoor human thermal comfort. On the pedestrian scale, vegetation plays a significant role in modifying the microclimate by providing shade and aiding the human thermal comfort via evapotranspiration. However, while the extensive tree canopy is beneficial in providing daytime shade for pedestrians, it may reduce the pavement surfaces' sky-view factor during the night, thereby reducing the rate of nighttime radiation to the sky and trapping the heat gained within the urban materials. This study strives to extend the understanding, and optimize the recommendations for the use of landscape in the urban context of Phoenix, Arizona for effectiveness in both improving the human thermal comfort and in mitigating the urban heat island effect.
ContributorsRosheidat, Akram (Author) / Bryan, Harvey (Thesis advisor) / Lee, Taewoo (Committee member) / Chalfoun, Nader (Committee member) / Arizona State University (Publisher)
Created2014
Description

The research topic for this assignment is shrimp farming in Thailand located throughout the coastal areas of the southern, eastern, and central regions of the country. Thailand’s huge shrimp export driven industry represents one of the largest in the world accounting for over twenty-five percent of food exports out of

The research topic for this assignment is shrimp farming in Thailand located throughout the coastal areas of the southern, eastern, and central regions of the country. Thailand’s huge shrimp export driven industry represents one of the largest in the world accounting for over twenty-five percent of food exports out of the country (Sriboonchitta & Wiboonpongse, n.d.).

Specific research questions include:
       1. What are the current unsustainable practices in shrimp farm production?
       2. In what part of the life cycle should intervention take place?
       3. What does a sustainable shrimp farming practice look like in the future?

Created2012-05
Description

Anticipatory LCA seeks to overcome the paucity of data through scenario development and thermodynamic bounding analyses. Critical components of anticipatory LCA include:
       1) Laboratory-scale inventory data collection for nano-manufacturing processes and
           preliminary performance evaluation.
       2) Thermodynamic modeling of manufacturing processes and developing scenarios

Anticipatory LCA seeks to overcome the paucity of data through scenario development and thermodynamic bounding analyses. Critical components of anticipatory LCA include:
       1) Laboratory-scale inventory data collection for nano-manufacturing processes and
           preliminary performance evaluation.
       2) Thermodynamic modeling of manufacturing processes and developing scenarios of     
           efficiency gains informed by analogous material processing industries.
       3) Use-phase bounding to report inventory data in a functional unit descriptive of
           performance.

Together, these analyses may call attention to environmentally problematic processes or nanotechnologies before significant investments in R&D and infrastructure contribute to technology lock in. The following case study applies these components of anticipatory LCA to single wall carbon nanotube (SWCNT) manufacturing processes, compares the rapid improvements in SWCNT manufacturing to historic reductions in the embodied energy of aluminum, and discusses the use of SWCNTs as free-standing anodes in advanced lithium ion batteries.

Created2012-05
Description

Our objectives are to:
       1. Review the LCA literature to determine the dominant environmental impact categories in
           wild-caught fisheries in order to evaluate which phases are causing the greatest impacts.
       2. Determine how these impacts can best be mitigated and develop a

Our objectives are to:
       1. Review the LCA literature to determine the dominant environmental impact categories in
           wild-caught fisheries in order to evaluate which phases are causing the greatest impacts.
       2. Determine how these impacts can best be mitigated and develop a framework that seeks
           to incorporates LCA into sustainable seafood guides so that consumers can make better-
           informed decisions.

This framework will include developing meaningful LCA impact categories for sustainable seafood guides. Despite their importance, we considered social factors beyond the scope of this paper.

Created2012-05
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Description
Learning from the anatomy of leaves, a new approach to bio-inspired passive evaporative cooling is presented that utilizes the temperature-responsive properties of PNIPAm hydrogels. Specifically, an experimental evaporation rate from the polymer, PNIPAm, is determined within an environmental chamber, which is programmed to simulate temperature and humidity conditions common in

Learning from the anatomy of leaves, a new approach to bio-inspired passive evaporative cooling is presented that utilizes the temperature-responsive properties of PNIPAm hydrogels. Specifically, an experimental evaporation rate from the polymer, PNIPAm, is determined within an environmental chamber, which is programmed to simulate temperature and humidity conditions common in Phoenix, Arizona in the summer. This evaporation rate is then used to determine the theoretical heat transfer through a layer of PNIPAm that is attached to an exterior wall of a building within a ventilated cavity in Phoenix. The evaporation of water to the air gap from the polymer layer absorbs heat that could otherwise be conducted to the interior space of the building and then dispels it as a vapor away from the building. The results indicate that the addition of the PNIPAm layer removes all heat radiated from the exterior cladding, indicating that it could significantly reduce the demand for air conditioning at the interior side of the wall to which it is attached.
ContributorsBradford, Katherine (Author) / Reddy, T A (Thesis advisor) / Bryan, Harvey (Thesis advisor) / Ramalingam, Muthu (Committee member) / Arizona State University (Publisher)
Created2018
Description

Meaningful sustainable consumption patterns require informed consumers who understand the actual impact of their actions on a quantitative and tangible basis. Life cycle assessment (LCA) is a tool well suited to achieving this goal, but has only been superficially applied to the analysis of plant-based diets. This analysis looks at

Meaningful sustainable consumption patterns require informed consumers who understand the actual impact of their actions on a quantitative and tangible basis. Life cycle assessment (LCA) is a tool well suited to achieving this goal, but has only been superficially applied to the analysis of plant-based diets. This analysis looks at a common component of plant-based meat alternatives: a wheat-based protein known as seitan, which is a common substitute for beef. A comparative consequential analysis shows the overall change in environmental impact when 1000 servings of seitan displace 1000 servings of beef. The functional unit for comparison is one serving of seitan or one serving of beef and the system boundaries include production but not distribution, consumption or disposal. Life cycles are created for seitan and beef in the LCA modeling software SimaPro and an analysis is run using the Eco-indicator 99 methodology. The beef life cycle is created using complete existing LCA data, while the seitan life cycle is created using LCA data for constituent materials and processes.

Findings indicate that beef is much more environmentally impactful than seitan, but the largest difference is found in land use change. Significant data quality and uncertainty issues exist due to the data being incomplete or not representative for US processes and the use of proxy processes to estimate industrial processing. This analysis is still useful as a screening tool to show rough differences in impact. It is noted that despite seitan having a lower environmental impact than beef, increasing seitan production will probably have the effect of increasing overall environmental impacts, as beef production is not likely to decrease as a result. Massive changes in consumer purchase patterns are required before reductions in impact can be expected. Recommendations for future work include expanding system boundaries and obtaining industry specific data for seitan production.

Created2012-05
Description

Urban landscaping palm tree waste in the form of palm frond trimmings and bark shavings that is currently handled as municipal solid waste by the City of Phoenix and other major municipalities can be handled in more cost effective ways and lead to reductions in emissions and greenhouse gases. While many cities have

Urban landscaping palm tree waste in the form of palm frond trimmings and bark shavings that is currently handled as municipal solid waste by the City of Phoenix and other major municipalities can be handled in more cost effective ways and lead to reductions in emissions and greenhouse gases. While many cities have green organics collection and diversion programs, they always exclude palm tree waste due to its unique properties. As a result, an unknown tonnage of palm tree waste is annually landfilled as municipal solid waste. Additionally, as the tonnage is unknown, so are the associated emissions, greenhouse gases, and costs. An attributional lifecycle assessment was conducted in the City of Phoenix from the perspective responsibility of the City of Phoenix’s Public Works Department.

Created2013-05
Description

Many relationships exist between humans and their animal companions. Regardless of the relationship, the costs of pet ownership are more than just veterinary bills and the purchase of pet food. The purpose of this study is to examine the environmental impacts associated with ownership of canus lupus familiaris, more commonly

Many relationships exist between humans and their animal companions. Regardless of the relationship, the costs of pet ownership are more than just veterinary bills and the purchase of pet food. The purpose of this study is to examine the environmental impacts associated with ownership of canus lupus familiaris, more commonly known as the domesticated dog. Since dogs are carnivorous by nature, there has already been significant interest in the ecological ‘pawprint’ of pet food, or the pressure that dog food production exerts on the environment.

This study utilizes Life Cycle Assessment (LCA) to determine the environmental impacts of industrial pet food production and furthermore, pet ownership through nutritional requirements. Additionally, this study aims to examine how pet food type—beef or lamb—can influence greenhouse gas (GHG) emissions. The approach taken by this study is that of a hybrid input-output LCA, combining Economic Input Output (EIO-LCA) data and process-level data to examine how supply chain decisions made by pet food manufactures can affect the ecological ‘pawprint’ of the domestic dog. The EIO-LCA provides an economy-wide lens, whereas, process-based LCAs provide data relevant to specific materials and processes. This approach was used to compare the environmental impacts associated with environmentally friendly supply chain decisions compared to the typical environmental impact of dog food.

Created2013-05
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Description

An increase in population and need to protect the planet has created many initiatives and research goals in developing alternatives methods of fueling. Federal and state policies have provided a push for industries to find ways to of reducing their impact on the environment while maintaining competitiveness. In the sector

An increase in population and need to protect the planet has created many initiatives and research goals in developing alternatives methods of fueling. Federal and state policies have provided a push for industries to find ways to of reducing their impact on the environment while maintaining competitiveness. In the sector of alternative fuels, large policies such as the Renewable Fuel Standards (RFS) in the United States are making goals to reduce vehicular fuel from coal and oil, and focus on alternative fuels such as ethanol and biodiesel. Along with the RFS and other federal policies, states are introducing independent initiatives to promote the use of alternative fuels.

Research has shown that other crops besides corn can feasibly be used to produce ethanol for fuel use. One of the major crops of interest currently is switchgrass (Panicum Virgatum L.) because of its ability to grow under a variety of weather conditions and soil types. Switchgrass does not require as much maintenance as corn and is a perennial grass that can have high yielding fields for up to 9 years.

This report focuses on the impacts from using switchgrass-derived ethanol to meet the state of Arizona’s policy to have government fleet vehicles operating on alternative fuels. The study uses a life cycle assessment (LCA) approach to evaluate 22 million gallons of ethanol produced in Arizona and stored at fueling stations for use. Impacts in land use, global warming, and water quality are evaluated using software tools and databases in Ecoinvent and Simapro.

The results of the study indicate that the cultivation and harvest phase of the process will contribute the most to negative environmental impacts. According to the study, application of heavy nutrient fertilizer and the machinery needed for the additional agriculture have the potential to contribute over 36 million moles of hydrogen and 89 million CTU eq. to the air, soil, and water.

Created2013-05