Comparative Environmental Assessment of Three Urine Recycling Scenarios: Influence of Treatment Configurations and Life Cycle Modeling Approaches.

Comparative life cycle assessment of standard, cellulose-reinforced and end of life tires fiber-reinforced hot mix asphalt mixtures

Background, aim and scope Regional specificities are a key factor when analyzing the environmental impact of a biofuel pathway through a life cycle assessment (LCA). Due to different energy mixes, transport distances, agricultural practices and land use changes, results can significantly vary from one country to another. The Republic of Argentina is the first exporter of soybean oil and meal and the third largest soybean producer in the world, and therefore, soybean-based biodiesel production is expected to significantly increase in the near future, mostly for exportation. Moreover, Argentinean biodiesel producers will need to evaluate the environmental performances of their product in order to comply with sustainability criteria being developed. However, because of regional specificities, the environmental performances of this biofuel pathway can be expected to be different from those obtained for other countries and feedstocks previously studied. This work aims at analyzing the environmental impact of soybean-based biodiesel production in Argentina for export. The relevant impact categories account for the primary non-renewable energy consumption (CED), the global warming potential (GWP), the eutrophication potential (EP), the acidification potential (AP), the terrestrial ecotoxicity (TE), the aquatic ecotoxicity (AE), the human toxicity (HT) and land use competition (LU). The paper tackles the feedstock and country specificities in biodiesel production by comparing the results of soybean-based biodiesel in Argentina with other reference cases. Emphasis is put on explaining the factors that contribute most to the final results and the regional specificities that lead to different results for each biodiesel pathway.

Life-cycle analysis of flow-assisted nickel zinc-, manganese dioxide-, and valve-regulated lead-acid batteries designed for demand-charge reduction

ENVIRONMENTAL SYSTEM ANALYSIS FOR HORTICULTURAL CROP PRODUCTION

In order to meet the upscaling demand of food products worldwide, the aquaculture industry has been expanding within the last few years in developed countries. Major expansions of aquaculture farming occurred in many developed countries such as Bangladesh, Indonesia, and Egypt. Egypt ranks ninth in fish farming production worldwide and first on Africa. Egypt has the largest aquaculture industry in Africa which represents two-thirds of African aquaculture production. Tilapia production accounts for 75.5 % of aquaculture production in Egypt. Tilapia aquaculture production has grown exponentially in recent decades until it reached 4.5 million tonnes in 2012 placing Egypt as the second worldwide producer of tilapia after China. The production of tilapia is practiced in different production systems including intensive and semi-intensive systems. These production systems require different resources and impact differently on the environment. The aim of the current study was to model the environmental performance of tilapia production and compare semi-intensive and intensive production systems. The main questions were the following: What are the different impacts of tilapia production on the environment? Which production system is more environmentally friendly? What are the preferable practices for better environmental performance and sustainable ecofriendly industry of Tilapia production? Life cycle assessment (LCA) was employed to determine the environmental impacts of tilapia production and compare semi-intensive and intensive production systems. Data for life cycle inventory were collected from two case study farms for tilapia production in Egypt. Four impact categories were taken into consideration: Global Warming Potential (GWP), Acidification Potential (AP), Eutrophication Potential (EP), and Cumulative Energy Demand (CED). LCA revealed that production of tilapia in intensive farming has less impact on GWP, AP, and CED, while its impact on EP is higher than in semi-intensive farming. The identified impacts from 1-tonne live weight production of tilapia were the following: GWP 960.7 and 6126.1 kg CO2 eq; AP 9.8 and 24.4 kg SO2 eq; EP 14.1 and 6.3 kg PO2 eq; and CED 52.8 GJ and 238.3 GJ eq in intensive and semi-intensive systems, respectively. Fish meal production and energy consumption were the major contributors to different impact indicators in both systems. An overall improvement in environmental performance for tilapia production can be achieved by novel feed formulations that have better environmental performance. Energy consumption is a major area for improvement as well, as proper energy management practices will reduce the overall impact on the environment.

Dual upflow reactive filtration by a slowly moving sand bed with continuously renewed, hydrous ferric oxide‐coated sand is used for removing polluting substances and for meeting the ultralow 0.05 mg/l total phosphorus discharge permit limits at a 1.2 million liters per day (0.32 million gallons per day) water resource recovery facility in Plummer, Idaho, in the United States. A life cycle assessment (LCA) of this reactive filtration installation was carried out to assess the environmental hotspots in the system and analyze alternative system configurations with a focus on CO2 equivalent (CO2e) global warming potential, freshwater and marine eutrophication, and mineral resource scarcity. “What if” scenarios with alternative inputs for the energy, metal salts, and air compressor optimization show trade‐offs between the impact categories. Key results that show a comparative reduction of global warming potential include the use of Fe versus Al metal salts, the use of renewable energy, and the energy efficiency benefit of optimizing process inputs, such as compressor air pressure, to match operational demand. The LCA shows a 2 × 10−2 kg CO2e footprint per cubic meter of water, with 47% from housing concrete, and an overall freshwater eutrophication impact reduced by 99% versus no treatment. The use of renewable hydropower energy at this site isolates construction concrete as a target for lowering the CO2e footprint.Practitioner PointsThe main LCA eco‐impact hotspots in this dual reactive filtration tertiary treatment are construction concrete and the ferric sulfate used.Iron salts show smaller impact in global warming, freshwater eutrophication, and mineral resource scarcity than “what if scenario” aluminum salts.The energy mix for this site is predominantly hydropower; other energy mix “what if” scenarios show larger impacts.Operational energy efficiency and thermodynamic analysis show that fine tuning the air compressor helps reduce carbon footprint and energy use.LCA shows a favorable 2 x 10‐2 kg CO2e/m3 water impact with 99% reduction of freshwater eutrophication potential versus no treatment.

Life cycle assessment (LCA) had proven to be an appropriate assessment tool for analysis of agro-ecosystems by identifying, quantifying, and evaluating the resources consumed and released into the environment. In order to assess the relevant environmental impacts of rice agro-ecosystems due to a specific process, using LCA method, two factors concerned with resource utilization and contaminant emissions were calculated in north of Iran during 2016 and 2017. All the management practices/inputs were monitored and recorded with the help of local experts without interference in farmer's practices. After preliminary evaluation, 100 paddy fields were selected in three planting systems (low input, conventional, and high input) which were predicted in two planting methods (semi-mechanized and traditional) in small, medium, and large farm size levels. Functional unit was considered as one ton paddy yield. The finding revealed that in both regions, all the impact categories and environmental pollutant were almost same and farmer's management practices are close to each other. Also, climate change (CC) in Amol and Rasht regions was 277.21 and 275.79kgCO2eq., respectively. The most CC, global warming potential (GWP 100a), and cumulative energy demand (CED) in both regions were observed in high-input system for semi-mechanized method. Furthermore, the result for the impact categories of terrestrial acidification (TA), freshwater eutrophication (FE), marine eutrophication (ME), agricultural land occupation (ALO), water depletion (WD), metal depletion (MD), and fossil depletion (FD) was similar to the CC, GWP, and CED where the highest amounts in both regions statistically went to high-input system, traditional planting method, and small farms. Moreover, in both regions, high-input and conventional systems emitted higher heavy metals than low-input system. Furthermore, the most heavy metal emission in the air was achieved in small farm, and medium farm got the next rank. Additionally, the high consumption of chemical inputs, such as fossil fuels and fertilizers, in the high-input and conventional systems led to an increase of environmental pollutant in comparison with low-input systems. Therefore, to increase the sustainability of agro-ecosystems, as well as to reduce the environmental impacts of pollutant, reforming the pattern of chemical input consumption and reducing the use of non-renewable energy sources are essential.

PurposeCultured meat is produced by cultivating animal cells in a bioreactor in a culture medium that provides nutrients and growth factors. Among other animal sera, fetal bovine serum (FBS) has traditionally been the most common used in the culture medium of mammalian cell cultures, i.e., 10% FBS medium that contains 10% FBS and 90% DMEM/F12 (v/v). As the aim of cultured meat is to replace livestock production, animal component-free culture media needs to be developed. MethodsWe analyzed the environmental impact of replacing the 10% FBS culture medium with serum substitutes, i.e., growth factors, Essential 8™, protein hydrolysates from egg-white, eggshell membrane, poultry residues, pork plasma, and pea concentrate, and Tri-basal 2.0 + ITS medium that contains fibroblast growth factor (FGF-2), fetuin, bovine serum albumin (BSA), and insulin transferrin selenium (ITS). Life cycle assessment with a cradle-to-gate approach was used to quantify global warming potential, freshwater and marine eutrophication, terrestrial acidification, land use, water consumption, fossil resource scarcity, particulate matter formation, cumulative energy demand, and ozone formation of preparing 1-L culture medium. Sensitivity analysis was conducted to examine the impact changes under various production conditions including variations in the impact allocation strategy, production location, and energy sourcing.Results and discussionThe 2% FBS medium (2% FBS, 96% DMEM/F12, and 2% growth factors (v/v)) reduced all environmental impacts where marine eutrophication had the highest reduction (77%), while land use was the least affected with a reduction of 6%. The Tri-basal 2.0 + ITS and protein hydrolysates media reduced most of the analyzed environmental impacts. Protein hydrolysates from egg-white had the lowest environmental impacts reducing 81% global warming potential, 28% water consumption, 59% fossil scarcity, 87% eutrophying emissions, 91% terrestrial acidification, 82% particulate matter, and 70% ozone formation, compared to FBS-containing medium. Land use and energy demand were reduced the most by 17 and 37%, respectively, when the 10% FBS medium was replaced with the Tri-basal 2.0 + ITS medium.ConclusionsChanging the input of FBS in culture media from 10 to 2% (v/v) reduced all studied environmental impacts. Further reductions were achieved when FBS was totally replaced by basal media DMEM/F12, Essential 8™, protein hydrolysates, and recombinant growth factors. Land use was the least reduced, as it was driven by starch extraction to produce glucose for the DMEM/F12 basal medium. Culture medium with protein hydrolysates from egg-white achieved the highest impact reductions compared with the FBS-containing medium.

Life cycle assessment (LCA) has been widely applied to improve the environmental performance of the building sector. However, due to the complexity of LCA results including the multitude of impact categories, decision makers of the building materials manufacturing industry are grappling with allocating their limited resources to the most influential impact categories. The aim of this article, therefore, is to propose an impact category selection tool that enables performance improvement of building materials without sacrificing the validity of LCA results. The developed method selects common building materials, and defines foreground processes that can be influenced by manufacturers of building materials and background processes that can hardly be impacted using the US Input-Output database. Following the life cycle impact assessment (LCIA) analysis with the ReCiPe2016 Midpoint method, our results indicate that, among the 18 impact categories of the ReCiPe2016 Midpoint method, Global Warming Potential, Ozone Formation and Human Health, Fine Particulate Matter Formation, Ozone Formation and Terrestrial Ecosystems, Terrestrial Acidification, and Terrestrial Ecotoxicity should be considered the first priority group while Ionizing Radiation, Freshwater Eutrophication, Marine Eutrophication, Freshwater Ecotoxicity, Water Consumption should be placed in the last priority group. It further suggests that by shifting the limited available resources to the first priority group, decision makers can readily improve the environmental performance of building materials during the manufacturing process. The contribution of the proposed selection tool lies in that it can be adapted by decision makers to different geographical contexts, LCIA methods, and building materials to efficiently ameliorate the environmental performance of the building sector.

Can thermal intensification be considered a sustainable way for greening Fenton processes?

Biodiesel fuel has received considerable attention as a more sustainable alternative to traditional fuel. This paper presents a life cycle assessment (LCA) for producing biodiesel fuel from waste vegetable oil (WVO). Comparisons are made for different methods of dealing with additional products. The LCA is a cradle to fuel model that includes the following unit processes: soybean farming, soy meal and soy oil extraction, processing of soy oil, cleaning/drying waste oil, transesterification to produce useful biodiesel and transportation to various sites. Metrics evaluated to determine sustainability include global warming potential (GWP) and cumulative energy demand (CED). Values are obtained using GREET1. Credits for additional products must be applied in the LCA. WVO is a byproduct of oil produced for cooking fried products. We account for oil consumed in the cooking process using two approaches. In the first approach, the amount of oil consumed in the cooking process is credited to the WVO. All the cooking oil is considered WVO. In the second approach, the WVO is considered a “free” product. This means only the CED and GWP associated with WVO transportation, processing and transesterification are included in the LCA. Other co-products are considered applying two traditional methods used in LCA: mass-based allocation and displacement. In mass-based allocation, CED and GWP are adjusted considering the mass fraction of soy oil produced from soybeans and the mass fraction of biodiesel produced from WVO in the transesterification process. In the displacement method, soymeal is considered to displace soybeans as animal feed and glycerin displaces synthetic glycerin. The CED and GWP of the displaced products are subtracted as credits. LCA results for the various approaches to additional products are compared. We demonstrate a wide range of results are possible. These results should provide useful information for dealing with additional products in determining the sustainability of producing biodiesel fuel from waste vegetable oil.

An environmental impact assessment of quantum dot photovoltaics (QDPV) from raw material acquisition through use

Novel food production technologies are being developed to address the challenges of securing sustainable and healthy nutrition for the growing global population. This study assessed the environmental impacts of microbial protein (MP) produced by autotrophic hydrogen-oxidizing bacteria (HOB). Data was collected from a company currently producing MP using HOB (hereafter simply referred to as MP) on a small-scale. Earlier studies have performed an environmental assessment of MP on a theoretical basis but no study yet has used empirical data. An attributional life cycle assessment (LCA) with a cradle-to-gate approach was used to quantify global warming potential (GWP), land use, freshwater and marine eutrophication potential, water scarcity, human (non-)carcinogenic toxicity, and the cumulative energy demand (CED) of MP production in Finland. A Monte Carlo analysis was performed to assess uncertainties while a sensitivity analysis was used to explore the impacts of alternative production options and locations. The results were compared with animal- and plant-based protein sources for human consumption as well as protein sources for feed. Electricity consumption had the highest contribution to environmental impacts. Therefore, the source of energy had a substantial impact on the results. MP production using hydropower as an energy source yielded 87.5% lower GWP compared to using the average Finnish electricity mix. In comparison with animal-based protein sources for food production, MP had 53–100% lower environmental impacts depending on the reference product and the source of energy assumed for MP production. When compared with plant-based protein sources for food production, MP had lower land and water use requirements, and eutrophication potential but GWP was reduced only if low-emission energy sources were used. Compared to protein sources for feed production, MP production often resulted in lower environmental impact for GWP (FHE), land use, and eutrophication and acidification potential, but generally caused high water scarcity and required more energy.

Life cycle and economic assessment of corn production practices in the western US Corn Belt

Life cycle assessments of municipal solid waste management systems: A comparative analysis of selected peer-reviewed literature