Global Warming Category Research Articles

Advancing Sustainability in a Residential Building in Europe: A Case Study on LCA and LCC across Different Scenarios

This study evaluates the environmental and economic performance of the "ESTIA of Athens" residential building considering its energy consumption and greenhouse gas (GHG) emissions. It also explores the potential for improvements in these areas. The European Union's strategy to reduce GHG emissions from buildings by 55% compared to 1990 levels by 2030, as part of its broader aim for climate neutrality by 2050 is a background for the study. The methodology involves a Life Cycle Assessment (LCA) using SimaPro software, monitoring energy consumption, temperature and humidity of the building. The thirteen impact categories and damage impact assessment that include human health, ecosystem and resources were examined. The study compares various scenarios, including historical data from 2018 to 2022 and two hypothetical scenarios to assess environmental impacts across different categories. Additionally, Life Cycle Costings (LCC) are performed to evaluate the economic aspects of the building's performance. The results highlight substantial differences in energy consumption, GHG emissions and economic costs among the scenarios. The findings suggest that a hypothetical scenario, referred to as Case 3, demonstrates lower environmental impacts and economic costs compared to other scenarios, indicating its potential as an optimal renovation strategy for the building. This includes reductions of 32%, 40% and 58% in the human health, ecosystems, and resources categories, respectively. A similar trend is observed across the impact categories, with reductions ranging from 4% in the Mineral Resource category to 47% in the Global Warming category. The study underscores the importance of holistic assessments in informing energy policy and renovation strategies for achieving both environmental sustainability and economic viability in buildings.

Life cycle assessment of food consumption in different cities: Analysis of socioeconomic level and environmental hotspots

This study presents a comprehensive life cycle assessment of the environmental impacts of dietary patterns in different cities, focusing on the correlation between food consumption and environmental impact. The functional unit was the food required to meet one person's yearly needs (1 Inh/year). To determine the quantity and type of food consumed, as well as the income level of the residents, 523 surveys were conducted in households in four cities in Chile (Iquique, Santiago, Temuco, and Coyhaique). Survey data were complemented with secondary information from national statistics and the Ecoinvent database. The environmental impact assessment was carried out using SimaPro, selecting the categories of global warming, terrestrial acidification, terrestrial ecotoxicity, freshwater ecotoxicity, freshwater eutrophication, land use, and fossil resource scarcity. The results show that higher-income households generate greater environmental impacts attributed to higher per capita food consumption. In the global warming category, the environmental impact can range from 1.08 kg CO2 eq/inh/year for the first quintile to 2.15 kg CO2 eq/inh/year for the fifth quintile in Santiago. In this category, the impacts in the highest quintiles can be up to 2.2 times greater than those in the lowest quintiles. Similarly, in acidification, this difference can reach 2.3 times. In the freshwater eutrophication category, the highest-income quintiles can double the environmental impacts compared to the lowest (I and II), mainly due to higher consumption of red meat and dairy products. The food production stage was the environmental hotspot across all evaluated impact categories, accounting for 45%–60% of the impacts in global warming, terrestrial ecotoxicity, and fossil resource scarcity; 74%–78% in terrestrial acidification, freshwater eutrophication, and land use; and 68%–71% in freshwater ecotoxicity. Meat was pinpointed as the primary environmental hotspot in global warming (44%), terrestrial acidification (56%), freshwater eutrophication (50%), land use (35%), and fossil resource scarcity (30%). Conversely, cereals are the primary environmental hotspot in terrestrial ecotoxicity (30%) and vegetables in freshwater ecotoxicity (18%). The geographical location of cities also influenced the environmental impacts of food consumption, primarily due to the types of available foods in regions near each city. Food availability conditions, diets, and quantities consumed, thus influencing environmental impacts. Finally, household incomes, the geographical location of cities, and the food production systems in each city determine the environmental impacts of food consumption. Different configurations of these variables create unique environmental impact profiles for each city. Despite this, typical environmental hotspots in food consumption were identified across all cities, enabling the implementation of strategies to minimize environmental impacts on a national scale. Thus, circular economy strategies linked to food production systems, as well as food loss and waste, could significantly reduce environmental impacts, presenting an intriguing opportunity for future research in this field.

Hybrid Life Cycle Assessment (LCA) of prefabrication: A comparison of conventional and mixed reality-based solutions

Conventional prefabrication in construction is causing distinct challenges, including environmental pollution and high energy usage. However, integrating emerging technologies such as Mixed Reality (MR) in prefabrication is expected to mitigate the environmental impacts and improve overall sustainability. This study evaluates and analyses the environmental benefits and burdens associated with implementing MR technologies in prefabrication compared to conventional prefabrication. The production stages in prefabrication, including reinforcement, side formworks, concreting, and human labor, have been identified as primary unit processes, and their respective contributions to the overall environmental impact have been assessed. A comprehensive assessment using a hybrid Input-Output Life Cycle Assessment (IO-LCA) model, while incorporating human labor hours is necessary for a thorough environmental assessment. The cradle-to-gate LCA results of a declared unit of 1 m3 volume of conventional prefabrication are compared with MR-enabled prefabrication. The results show that using MR technology in prefabrication significantly decreases the environmental burdens of the prefabrication in impact categories of Global warming (8%), Terrestrial acidification (8%), Marine eutrophication (10%), and Stratospheric ozone depletion (17%). Furthermore, with the higher levels of MR implementation, there is a significant reduction (around 60%) in the environmental impact associated with prefabrication. Accordingly, the contribution of MR technology in designing, planning, monitoring, assembling, and collaborating in prefabrication leads to effective resource management, minimization of waste, and enhancement of overall efficiency. The reinforcement process has notably elevated environmental impact in prefabrication while recognizing the improvement opportunities through MR implementation. MR-enabled quality inspection is of great importance in significantly reducing environmental burdens.

Livestock waste management for energy recovery in Brazil: a life cycle assessment approach.

Livestock farming has exerted intense environmental pressure on our planet. The high emissions to the environment and the high demands of resources for the production process have encouraged the search for decarbonization and circularity in the livestock sector. In this context, the objective of this study was to evaluate and compare the environmental performance of two different uses for biogas generated in the anaerobic digestion of animal waste, either for electricity generation or biomethane. For this purpose, a life cycle assessment approach was applied to evaluate the potential of anaerobic digestion as a management technology for three different livestock wastes, related to beef cattle, dairy, and sheep in the Brazilian animal production context. The results suggest that the treatment scenarios focusing on biomethane generation were able to mitigate the highest percentage of damages (77 to 108%) in the global warming category when compared to the scenarios without the use of anaerobic digestion (3.00·102 to 3.71·103 kgCO2 eq) or in the perspective of electricity generation (mitigation of 74 to 96%). In terms of freshwater eutrophication, the generation of electricity (- 2.17·10-2 to 2.31·10-3 kg P eq) is more favorable than the purification of biogas to biomethane (- 1.73·10-2 to 2.44·10-3 kg P eq), due to the loss of methane in the upgrading process. In terms of terrestrial ecotoxicity, all scenarios are very similar, with negative values (- 1.19·101 to - 7.17·102 kg 1,4-DCB) due to the benefit of nutrient recovery, especially nitrogen, associated with the use of digestate as fertilizer, which was one of the critical points in all scenarios. Based on these results, it is evident that proper management of all stages of the treatment life cycle is the key to decarbonization and circularity in livestock waste management. The biogas use does not present different effects on the environmental performance of the scenarios studied, demonstrating that the purpose should be chosen according to the needs of each plant or management system.

A comparative life cycle assessment of tyre recycling using pyrolysis compared to conventional end-of-life pathways

End-of-life tyres (ELTs) are difficult to recycle due to their complex composition. Although there are several possible pathways to manage ELTs, in Germany roughly 50 % of the ELTs are still incinerated. One emerging technology that promises recycling of ELTs is the thermochemical processing through pyrolysis. This technology enables to recover carbon black and pyrolysis oil that can be reused for new tyres. Therefore, this study presents a comprehensive life cycle assessment to compare the environmental impacts from pyrolysis of ELTs against current dominant alternative end-of-life treatment pathways. The investigated alternative end-of-life pathways are (i) incineration in a cement plant, (ii) incineration in a dedicated incineration plant, and (iii) production of infills for artificial turfs. The results show that the recycling of ELTs for material recovery has lower environmental impacts in the categories global warming, particulate matter and resource use compared to end-of-life pathways that target energy recovery.

Life Cycle Assessment of Poplar Biomass for High Value Products and Energy

The European Union has embarked on a European Green Deal programme that advocates for a transition from fossil fuels to sustainable production. Attempts are being made to identify biomass sources and bioproducts (pharmaceuticals, cosmetics, or biofuels) that do not compete significantly with food production and have a low environmental impact. Therefore, the aim of this study was to determine the environmental impact of the supercritical CO2 extraction of poplar biomass in a life cycle assessment (LCA). The production system was examined in a cradle-to-gate approach. In the analysed system, poplar biomass was extracted, and residual biomass was converted to pellets which were used to generate process heat. The functional unit was 1 kg of packaged extract. The results showed that the step of biomass extraction using S-CO2 (in subsystem II) made the greatest contribution to all but two impact categories, with contribution from 25.3% to 93.8% for land use and global warming categories, respectively. In contrast, the whole subsystem I (biomass production and logistics) had a low environmental impact. Heat generation from residual biomass led to a minor decrease in the system’s environmental impact. Greenhouse gases emission reached 440 kg of CO2 equivalents per 1 kg of the extract, and they were associated with high electricity consumption and steam production. Despite the application of residual biomass for heat generation, the overall environmental impacts, especially in terms of human health and ecosystem damage, remain significant, indicating the need for further optimisation and mitigation strategies in the production process. Moreover, the share of renewables in the energy mix supplied to biorefineries should mitigate the environmental impact of the extraction process.

Life cycle assessment of food waste energy and resource conversion scheme via the integrated process of anaerobic digestion and hydrothermal carbonization

Anaerobic digestion is the mainstream method for energy conversion of food waste, but dewatering and resource utilization of its digestate is the downstream technical obstacle. In this study, an energy and resource utilization scheme via the integrated process of anaerobic digestion and hydrothermal carbonization of food waste is proposed, among which the hydrothermal carbonization not only is used to remove water from digestate in a non-phase change manner with low energy consumption but also convert digestate into hydrochar. Moreover, the scheme has the least environmental impact compared to the anaerobic digestion and composting treatment by life cycle assessment. In particular, it has a lower impact potential (−141.46 kg CO2 eq) than anaerobic digestion (−38.87 kg CO2 eq) for the global warming category, indicating that the addition of hydrothermal carbonization can bring better environmental benefits. This study provides a reference for the development of disposal technology for food waste.

Attributional and consequential life cycle perspectives of second-generation polylactic acid: The benefits of integrating a recycling strategy

The climate crisis calls for a shift from petrochemicals to bio-based products to reduce environmental consequences. Polylactic acid (PLA) is one of the most widely used biopolymers, due to its mechanical properties and renewable origin, to produce bio-based compostable plastic for food packaging. The objective of this study is to determine the environmental feasibility of a second-generation PLA production based on wheat straw; and the role of a chemical recycling plant on the environmental performance of a bioproduct at an early design stage. A holistic assessment was performed through the Life Cycle Assessment (LCA) methodology considering both attributional and consequential perspectives, through a cradle-to-grave approach. The attributional LCA results show that lactic acid production was the main contributor due to the wheat straw pre-treatment and downstream separation and purification (DSP) processes. The integration of a recycling plant leads to a significant reduction of burdens, ranging from 1.38 to 0.44 kg CO2eq in the Global Warming category. Furthermore, consequential LCA results shows that the increased demand for substitute products for activities such as feeding, fertilisation and energy generation and the indirect emissions from land use change related to the conversion of land for the cultivation of raw materials are relevant factors in the environmental effects associated with the possible implementation of straw-based bioPLA production system.

Life Cycle Assessment of Bioenergy Production Using Wood Pellets: A Case Study of Remote Communities in Canada

In remote communities of Canada, diesel is the primary source of electricity and heat. Promoting sustainable and diverse means of heat and power generation is essential to providing reliable and less carbon-intensive energy supply to remote communities. Among renewable energy sources in Canada, biomass is a major source of energy, with wood pellets being a notable contributor. In this study, using wood pellets in a remote community of Canada is investigated using life cycle analysis (LCA). Furthermore, wood pellet combustion is compared with diesel combustion, the most common fossil fuel in these regions. SimaPro (version 8.4.0.0) was used with Ecoinvent 3 as the primary library because of the nature of the feedstock. Harvesting, transportation, sawmill operation, pelletization, and combustion stages are considered in LCA. In doing so, first, life cycle data related to each of these stages are collected with respect to eight impact categories of global warming, ozone depletion, carcinogenic, non-carcinogenic, smog, respiratory effects, acidification, eutrophication, ecotoxicity, and fossil fuel depletion. The results indicate that pelletization and combustion stages have the greatest environmental impact, specifically in terms of non-carcinogenic effects from pelletization and respiratory effects from pellet combustion. Additionally, when comparing wood pellets to diesel, wood pellet combustion exhibits superior performance across various impact categories, particularly in non-carcinogenic effects.

Sustainable assessment and resource recycling opportunities identification for China's pig industry: Integrating environmental, economic and social perspectives

Livestock plays a vital role in the livelihoods and nutritional security of people worldwide and leads to significant environmental challenges. Manure management is a major hurdle for sustainable livestock development and serves as a critical source of natural fertilizer and green energy. Given that pork accounts for the highest meat production and consumption share, this study systematically evaluates China's pig production and main manure resource utilization scenarios from life-cycle environmental, economic, and social perspectives. Results show that China's pig production poses considerable potential environmental risks, primarily in the categories of fossil depletion, freshwater ecotoxicity, particulates formation, global warming, and water depletion. Feed production coupled with traditional manure treatment scenario contributes to 94.4 %–98.4 % of the key environmental impact categories and socioeconomic impact, with 32.0 % to 38.3 % of the economic costs also stemming from feed costs. In the energy utilization scenario, the potential benefits of fossil depletion and global warming categories resulting from the replacement of synthetic fertilizers with manure-based organic fertilizers in the traditional pig manure treatment scenario could be expanded by 89.6 % and 39.2 %, respectively. China's pig production contributed 0.72 % of the national carbon emissions in 2020. Fully utilizing energy potential and organic fertilizer from pig manure would achieve 0.63 % of national carbon reduction potential, as well as an economic benefit of $1.45 × 1012 and a social benefit of $8.89 × 109. Precision feeding technology, rebuilding the spatial connection between pig farms and arable land, and internalizing external costs were recommended to ensure the sustainable development of China's pig industry.

Environmental life cycle assessment of treatment and management strategies for food waste and sewage sludge

A consequential life cycle assessment (LCA) was utilized to compare the environmental impacts of food waste and sewage sludge management strategies. The strategies included a novel two-phase anaerobic digestion (AD) system and alternatives including landfill, waste-to-energy, composting, anaerobic membrane bioreactor, and conventional AD (wet continuous stirred-tank reactor [CSTR]). The co-management of food waste with sewage sludge was also considered for the two-phase AD system and for a conventional AD reactor. A multidimensional LCA approach was taken, considering the five-midpoint impact categories of global warming, smog, human health particulate, acidification, and eutrophication estimated using the U.S. EPA Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts. Co-management of food waste and sewage sludge using the novel two-phase AD system was shown to maximize energy recovery and had a net global warming benefit while reducing other environmental impacts compared with the alternative management strategies. It had similar relative environmental advantages across all categories as conventional AD, with the advantage of a smaller physical footprint. However, both approaches featured net environmental burdens when the background electric grid intensity fell below 0.25 kg CO2-eq kWh−1, as could be expected in a decarbonized electric future. Upgrading the biogas produced from AD to renewable natural gas can displace the use of fossil natural gas for other non-electricity energy requirements that are difficult to decarbonize and may extend the time period of significant environmental benefits of utilizing AD for organic waste management. Treatment of the nutrient-rich supernatant generated by the novel two-phase AD system could be an obstacle for utilities with stringent nutrient discharge limits. Future research and full-scale implementation are needed to demonstrate the benefits of the two-phase AD system predicted through this analysis.

Environmental impact of the production process of washing, assorting and packaging fresh potatoes and measures to mitigate it

SummaryPotato is a tuber that, due to its great variety, is available in the markets all year round. Moreover, it is a widely consumed product worldwide on the account of its affordability and versatility. Therefore, studying it in depth is significant from not only a nutritional or economic point of view, but also for considering its potential environmental impact. In this paper, a Life Cycle Assessment (LCA) model is developed to assess the environmental impact of a model 5 kg bag of fresh washed potatoes. It considers all phases of potato processing, from the time the potato enters the facility until it leaves the gate (gate‐to‐gate LCA). The phase of the process with the greatest environmental impact is the cleaning and classification phase, mainly due to the significant consumption of water used in the cleaning process. The general consumption and storage phases are also relevant environmental impact phases to consider. In the case of these phases, the electricity consumption resulting from the operation of the facilities and product cooling is particularly noteworthy. After establishing the critical points, based on the environmental impact perspective, this paper proposes three measures to reduce the environmental impact of the process. The application of these three measures would reduce the environmental impact by 40% in environmental impact categories such as acidification or by 32% in the global warming category.

Интеграция оценки жизненного цикла в практику выбора перспективной технологии функциональных пищевых ингредиентов

The research involved environmental assessment of technologies for the production of functional ingredients with oncoprotective functions on the basis of different raw materials: secondary resources – by-products of soybean oil production and plant raw materials (extracts from Filipendula ulmaria) in order to determine the environmental impact in their life cycle and to select the environmentally best of the considered technologies. The following biologically active substances were considered as research objects: microencapsulated phytosterols from by-products of soya oil production and nanoencapsulated extracts from wild and farmer Filipendula ulmaria. Life cycle assessment method was used as a research method as a tool to assess the environmental impact of production. Life cycle inventory analysis of technologies was carried out based on SimaPro 9.1.1.1.1 software using EPD (2018) V1.01, ReCiPe 2016 (Midpoint (H) V1.04/World (2010) H), and IPCC 2013 (GWP 500a V1.01) calculation models. Using the life cycle of functional ingredients for cancer prevention as an example, it is shown that the use soya oil production by-products is more environmentally friendly than the use of plant extracts from wild and farmer's labdanum (Filipendula ulmaria). The environmental impacts of the production technologies in the categories of global warming, eutrophication, acidification, and water consumption were quantified, confirming the superiority of phytostyrene from soya oil waste. The results obtained can be used to create a domestic information database for the selection of the best technologies for the production of biologically active substances and functional food ingredients, taking into account the environmental assessment of the life cycle.

Environmental impact assessment of vegetable production in West Java, Indonesia

Indonesia is one of the world's economies contributing the most to greenhouse gas (GHG) emissions from the global food system. This study aimed to quantify the environmental impacts of Indonesian vegetable production and the relative contribution of different farm inputs. Data were collected from 322 vegetable farms in the Lembang sub-district in West Java. A Life Cycle Assessment (LCA) was carried out to estimate global warming potential (GWP), acidification potential (AP), freshwater eutrophication potential (EP), and abiotic resource depletion. Results of the LCA showed that GHG emissions were 14.1 t CO2eq ha−1 yr−1 (0.5 t CO2eq t−1), AP was 39.3 kg SO2eq ha−1 yr−1 (1.4 kg SO2eq t−1), EP was 45.3 kg PO4eq ha−1 yr−1 (1.7 kg PO4eq,), and depletion of phosphate, potash, and fossil fuel resources were 60.0 kg P2O5, 101 kg K2O, and 6299 MJ ha−1 yr−1, respectively (1.9 kg P2O5, 3.7 kg K2O, and 281 MJ t−1). Organic fertilizer use contributed the most to impact categories of global warming, freshwater eutrophication, and acidification, followed by synthetic fertilizer. The sensitivity analysis showed that yield and organic fertilizer use explained most of the variation in GHG emission per ton product. Therefore, it is recommended to include organic fertilizer use in the fertilizer advisory system for vegetable production in Indonesia.

Environmental assessment of a single-family photocatalytic greywater treatment system based on the design and operating conditions

A life cycle assessment was carried out to compare the environmental impacts of an alternative water supply for toilet flushing in households with those of water currently supplied for this purpose through the municipal potable water network. In the proposed system, greywater from showers, baths and wash-hand basins is collected and treated using heterogeneous TiO2 photocatalysis. Several scenarios comprising different design and operating conditions were studied. Using the ReCiPe (H) 2016 method, the following environmental impact categories were assessed: global warming, stratospheric ozone depletion, terrestrial acidification, freshwater eutrophication, marine eutrophication, human carcinogenic toxicity, human non-carcinogenic toxicity, terrestrial ecotoxicity, freshwater ecotoxicity, marine ecotoxicity, and water consumption. The results show that for the water reuse device to be less impactful than the municipal water system in at least 7 of the selected impact categories by more than 20 %, the product between the number of reactors and the operating time should not exceed 8 reactors·h·day−1, also taking the influence of the UVA-LED's power into account. Of the 18 alternative scenarios analyzed, 14 present a potential for reducing the environmental impacts compared to the municipal water supply system in at least 7 of the 11 evaluated environmental impact categories. For instance, the municipal supply of one cubic meter of water and its subsequent wastewater treatment in the baseline scenario produces 4.21 kg CO2 eq·m−3, whereas only 1.62 kg CO2 eq·m−3 are produced in the optimum scenario of the greywater reuse system. Moreover, the use of solar photovoltaic panels as a source of electricity for the systems is found to be an effective measure to further improve the environmental performance, mainly for the impact categories of global warming, stratospheric ozone depletion, and terrestrial acidification. The study also highlights the benefits of recycling components and materials in the end-of-life stage of the proposed system.

Exploring the potential health and ecological damage of lead–zinc production activities in China: A life cycle assessment perspective

Lead and zinc are indispensable nonferrous metals in the current industrialized society because of their position as raw materials for various industrial products. However, the massive environmental burden imposed by the activities of the lead–zinc industry will trigger potential social impacts. This study systematically evaluated the environmental and social economic burden of lead–zinc production activities at the national level during the entire industrial chain via life cycle assessment coupled with economic assessment method. China, the world's largest lead and zinc metal producer, was used as an example. Results demonstrated that in 2018, the national values of the potential threats to human health, ecosystem quality, and social economy were 3.55 × 105 DALY, 1.27 × 104 species. yr, and 3.90 × 1010 $, respectively. The potential social economic impact of China's lead–zinc production increased by 49% from 2008 to 2018. Direct emission was the primary contributor in most environmental impact categories (i.e., freshwater ecotoxicity, particulates formation, non-carcinogens, and carcinogens), except for global warming, in which electricity generation was the main contributor. Heavy metals emitted during the mining and dressing stage provided the predominant contribution to ecosystem quality degradation. Copper discharged into water was identified as a key substance that accounted for 59% of the overall potential threats. Henan, Hunan, and Yunnan provinces were the dominant provinces contributing to the overall social economic impacts of lead–zinc smelting. Additionally, association analysis indicated a significant correlation between the lead–zinc smelting activities and multiple cancers (e.g., stomach, brain, liver, and colon cancers). Adopting environmentally-friendly and cost-effectiveness wastewater treatment technology (e.g., adsorption) or water reuse is recommended to reduce heavy metal emissions. The development of renewable electricity and implementing cross-regional electricity transmission options have important benefits for reducing the environmental and social economic burden of the lead–zinc production activities. The application of long-term marginal power would alleviate the environmental burden in global warming category by 32.1%. The dust removal technologies of selective catalytic reduction, electrostatic precipitator, and wet flue gas desulfurization are implemented in combination to remove carcinogenic heavy metals from the air to reduce health risks and socio-economic losses.

Life cycle assessment of polycarbonate production: Proposed optimization toward sustainability

The global plastics industry urgently requires a shift to sustainable manufacturing, but only a mere fraction of these plastics have been explored for their life cycle environmental impacts. Polycarbonate (PC), the top consumer of engineering plastics, lacks due attention. This study quantified the industrial-level environmental impacts of two mainstream PC production processes in China, the world's largest PC producer, via an integrated and regionalized life cycle impact assessment model. The fossil depletion category contributed dominant environmental impacts, accounting for approximately 60% in both scenarios. Bisphenol A production and coal mining and combustion were identified as crucial processes, specifying optimal directions toward sustainability. The PC green factories showed eco-effectiveness, with roughly 10% reductions in both non-carcinogens and global warming categories at the leading level. The mechanically recycled PC production could yield 82.3%–99.6% benefits in key categories. Moreover, green mines, ultra-low emission, bio-based plastics, and extended producer responsibility are highly recommended.

Life cycle assessment of sericin recovery from silk degumming wastewaters

Sericin is a silk protein discarded with silk degumming wastewater. Life cycle assessment of sericin recovery from silk degumming wastewater was conducted considering two scenarios; base scenario (no recovery), and sericin recovery with membrane hybrid processes. Base scenario consists of silk degumming and treatment of degumming wastewater. The recovery scenario consists of sericin recovery with the process train; silk degumming, sedimentation, nanofiltration (NF), precipitation and lyophilization. Spray drying was also considered as an alternative to the precipitation and lyophilization. The system boundary was set as cradle to grave and the functional unit was selected as 1 kg of sericin. The recovery scenarios had much higher environmental impacts as compared to the base scenario. In terms of kg CO2 equivalence, the impact of the recovery scenarios on climate change (global warming effect) was found to be approximately 2000–2650 times higher than the base scenario. In recovery scenario, endpoint impact score for climate change was as high as 50%, followed by natural resources (34%) and human health impacts (15%). The use of centrifugation + lyophilization option was found to cause 40%–50% more impacts compared to the spray drying option. The highest impact was for the nonrenewable energy impact category, followed by the global warming category. NF and sericin degumming were the processes with highest environmental impacts.

Introducing lupin in autochthonous wheat rotation systems in Galicia (NW Spain): An environmental and economic assessment.

Crop diversification, as a sustainable land management practice, is a potential strategy to face soil degradation, climate change and food security, being the incorporation of legumes in cereal rotation systems, a strategy that improves soil nutrient levels. In a context of sustainable agriculture, this manuscript aims to evaluate the effect of lupin cultivation from an environmental and economic perspective in Galician winter wheat-based rotation systems. The life cycle analysis (LCA) methodology was applied for three rotation systems over a six-year period: lupin + wheat + oilseed rape (RA1), lupin + potato + wheat (RA2), and lupin + wheat + oilseed rape + maize (RA3). The general approach of this study was to collect primary data associated with the rotation crops to quantify their environmental impacts and economic benefits and to identify their advantages or disadvantages. Comparing and contrasting the environmental profiles based on three functional units: hectare land (ha), financial indicator (gross margin, €) and yield production (kg of wheat grain) allows a robust evaluation of each crop rotation system. Relating to rotations without lupin, the results indicate that for the impact categories evaluated, the introduction of lupin proved to be favourable with notable reductions of 64% and 30% in the environmental categories of Global Warming and Marine Eutrophication, respectively. Moreover, favourable economic consequences were evident in rotations RA1 and RA2 with a 19% and 51% increase in financial indicators, respectively, but with a marginal reduction of 2% in gross margin in RA3. This study motivates stakeholders to understand the environmental impacts of diversification strategies in agricultural systems and serves as a baseline to address the assessment of the social aspects of these systems for a complete sustainability perspective.

A comparative life cycle assessment of biofertilizer production towards sustainable utilization of anaerobic digestate

Direct application of anaerobic digestate to agricultural soil has major environmental threats. Therefore, this study evaluates and compares four scenarios of digestate utilization as the first life cycle assessment (LCA) study conducted on these four scenarios. The four scenarios included (i) biofertilizer pellets (BFPs), (ii) biocompost (BC), (iii) liquid biofertilizer (LBF), and (iv) powder biofertilizer (PBF). The results showed that the LBF scenario was the best treatment choice, achieving environmental benefits in five of the ten impact categories examined; the highest was the marine aquatic ecotoxicity category (−141,304.03 kg 1,4-DB-eq./tonne digestate). Contrarily, the scenario with the least environmental benefits was the BC scenario in which it contributed to emissions in five categories; the most notable was the contribution to the global warming category with 25.68 kg CO2-eq./tonne digestate. However, all the studied scenarios achieved environmental gains compared to the chemical fertilizers, and the top three emission reduction categories were marine aquatic ecotoxicity, global warming, and human toxicity. This study provides a valuable reference and inventory data for digestate treatment options.