Quantification Of Environmental Impact Research Articles

Life cycle assessment of electric kick scooters: consolidating environmental impact quantification and concluding climate-friendly use options

BackgroundThe environmental impact of electric scooters has been the subject of critical debate in the scientific community for the past 5 years. The data published so far are very inhomogeneous and partly methodologically incomplete. Most of the data available in the literature suffer from an average bias of 34%, because end-of-life (EOL) impacts have not been modelled, reported or specified. In addition, the average lifetime mileage of shared fleets of e-scooters, as they are operated in cities around the world, has recently turned out to be much lower than expected. This casts the scooters in an unfavourable light for the necessary mobility transition. Data on impact categories other than the global warming potential (GWP) are scarce. This paper aims to quantify the strengths and weaknesses of e-scooters in terms of their contribution to sustainable transport by more specifically defining and extending the life cycle assessment (LCA) modelling conditions: the modelling is based on two genuine material inventories obtained by dismantling two different e-scooters, one based on a traditional aluminium frame and another, for the first time, based on plastic material.ResultsThis study provides complete inventory data to facilitate further LCA modelling of electric kick scooters. The plastic scooter had a 26% lower lifetime GWP than the aluminium vehicle. A favourable choice of electric motor promises a further reduction in GWP. In addition to GWP, the scooter's life cycles were assessed across seven other impact categories and showed no critical environmental or health impacts compared to a passenger car. On the other hand, only the resource extraction impact revealed clear advantages for electric scooters compared to passenger cars.ConclusionsUnder certain conditions, scooters can still be an important element of the desired mobility transition. To assure a lifetime long enough is the crucial factor to make the electric scooter a favourable or even competitive vehicle in a future sustainable mobility system. A scooter mileage of more than 5400 km is required to achieve lower CO2eq/pkm emissions compared to passenger cars, which seems unlikely in today's standard use case of shared scooter fleets. In contrast, a widespread use of e-scooters as a commuting tool is modelled to be able to save 4% of greenhouse gas (GHG) emissions across the German mobility sector.

Guidelines for disassembly and adaptation in architectural design compared to circular economy goals - A literature review

The application of Circular Economy (CE) in architectural practice is limited, despite the urgent need to reduce environmental burdens of the construction sector that CE offers. Design for Disassembly and Design for Adaptability (DfD/A) are recognised as key design strategies supporting CE. However, with further development of life-cycle assessment (LCA) or circularity factors (CF) that enable more life-cycle evaluations, the rationale for applying specific DfD/A guidelines needs to be revised. This paper aims to establish which DfD/A guidelines foster environmental benefits expected of the implementation of CE in architectural practice and under which conditions. Also, it is of interest whether quantification of environmental impact is consistent in guiding designers in CE compliant material choices and detailing. This literature review covers papers published before August 2022, with analysis of 2652 titles, 2031 abstracts and 70 full-texts, focusing on material choice, construction strategies, circular options and the related assessment methods (LCA, circularity assessment). The results indicate that only a few DfD/A guidelines unconditionally support CE goals in architectural design. The rationale for the application of most of the DfD/A guidelines requires a case-by-case analysis, both in terms of broader context assumptions and the related environmental impact. Furthermore, a multitude of scoring schemes and focus areas hinders practical comparison of materials and leads to divergent conclusions. Based on the findings, a design process framework is proposed, linking general CE and specific DfD/A guidance. In conclusion, policy and design community recommendations and further research needs are identified. A systematisation of LCA-methods and impact categories associated with specific industrial and business models is needed to avoid contradictory design recommendations.

An Index for Assessing the Environmental Impact of Pavement Maintenance Operations on the Motorway Network: The Environmental Asphalt Rating

In recent years, attention on pavement management is increasing and the research is focused on the development of innovative protocols and comparative evaluation of maintenance alternatives. Among these, the concept of sustainability related to the management of pavements is gaining ground and, more generally, infrastructure and the quantification of environmental impact as a combination of emissions and energy consumption. To properly estimate the environmental impact of different pavement interventions, a calculation methodology is presented in this paper that can summarize all the different aspects of environmental impact for both the production and paving phases of asphalt mixtures. The innovative approach takes into account also the need to evaluate new methodologies and new production processes in order to compare these new technologies with already used materials and processes. The result of this paper is a dimensionless index based on Environmental Product Declaration (EPD) certification which has been named Environmental Asphalt Rating (EAR) with weighting factors and performance coefficients fine-tuned on the European scenario. The EAR computation wants to be a certified procedure ensuring the repeatability and the quality of the environmental evaluation but also able to include in the evaluation noise and mechanical characteristics of the pavement. Several applications are expected such as the design stage of maintenance operations, and awarding criteria in tenders of monitoring phases of the pavement maintenance interventions.

OpenConcrete: a tool for estimating the environmental impacts from concrete production

As the increasing global consumption of concrete drives notable environmental burdens from its production, particularly greenhouse gas (GHG) emissions, interest in mitigation efforts is increasing. Yet current environmental impact quantification tools rely on user decision-making to select data for each concrete constituent, have inconsistent scopes and system boundaries, and often utilize third-party life cycle inventories. These factors limit customization or tracking of data and hinder the ability to draw robust comparisons among concrete mixtures to mitigate its environmental burdens. To address these issues, we introduce a cohesive, unified dataset of material, energy, and emission inventories to quantify the environmental impacts of concrete. In this work, we detail the synthesis of this open dataset and create an environmental impact assessment tool using this data. Models can be customized to be region specific, expanded to varying concrete mixtures, and support data visualization throughout each production stage. We perform a scenario analysis of impacts to produce a representative concrete mixture across the United States, with results ranging from 189 kg CO2-eq/m3 of concrete (California) to 266 kg CO2-eq/m3 of concrete (West Virginia). The largest driver of GHG, nitrogen oxide, sulfur oxide, and volatile organic compound emissions as well as energy demand is cement production, but aggregate production is the largest driver of water consumption and particulate matter smaller than 2.5 microns (PM2.5) emissions.

Integrated Sustainability Assessment: Exergy, Emergy, Life Cycle Assessment

Methodological tools such as Life Cycle Assessment (LCA), Exergy Analysis (ExA), and Emergy Analysis (EmA) that account for sustainability indicators in environmental, economic, and/or social dimensions, cannot provide an assessment under these three dimensions in a robust way by themselves. This research is proposing a sustainability assessment framework to obtain a unified performance metric (Integrated Sustainability Index, ISI) to assess the Triple Bottom Line – TBL. LCA, ExA, and EmA indicators are implemented in a complementary but not interchangeable manner, providing additional information for sustainability decision-making. The systematic approach is on a conceptual definition and calculation of sustainable environmental, social, and economic disaggregated indicators. These are then systematically combined into an Integrated Sustainability Index (ISI). EmA evaluates sustainability from a “donor-side” perspective, by assigning values to the environmental efforts and investment of nature to make and support flows, materials, and services; the system boundary is the geosphere. ExA evaluates sustainability through exergy efficiency under a “user-side” evaluation process (system boundary is the technosphere). LCA evaluates it based on the quantification of environmental impact by water, soil, and air emissions, caused by the use and processing of resources to provide products or services as a “user-side” method. The proposed sustainability index presents a comprehensible hierarchic structure supported by LCA, ExA, and EmA methodologies. The integration of social, environmental, and economic components into an index that also allows for the adjustment of externalities reducing the risk of subjectivity is a new approach to assessing sustainability.

A fully-printed electrochemical platform for assisted colorimetric detection of phosphate in saliva: Greenness and whiteness quantification by the AGREE and RGB tools

Herein, we report the environmental impact quantification of a newly developed fully printed electrochemical device to assist a colorimetric detection of phosphate in saliva. The evaluation of the analytical procedure was performed according to the principles of Green Analytical Chemistry and White Analytical Chemistry. The standard method for phosphate detection relies on a reaction between phosphate and molybdate in presence of antimony potassium tartrate and ascorbic acid, using strong acid conditions and high volumes of reagents (100–500 mL). To deliver an eco-friendly method, we have combined a screen-printed electrode with a liquid electrolyte battery and inkjet-printed conductive paths to develop a fully printed device on a flexible polymer substrate avoiding the use of ascorbic acid and using a small amount of reagents. The printed sensor was first developed and optimized for phosphate detection in saliva, allowing for a detection limit equal to 26 µM and satisfactory repeatability (relative standard deviation value of 7.5%). Finally, the AGREE and the RGB assessment tools were applied for a quantitative evaluation of the proposed sensor and reference method, in agreement with the Green Analytical and White Analytical principles. The results demonstrated the lower environmental impact of the proposed sensor, as well as the suitability of this novel approach for phosphate detection in saliva.

Quantification of environmental impact of water pollutants using fuzzy comprehensive model

Quantification of environmental impact of water pollutants using fuzzy comprehensive model

Auditing carbon reduction potential of green concrete using life cycle assessment methodology

The production of concrete in its traditional form have reported a notable impact on the environment in terms of resource depletion and the carbon footprint it generates in the entire life cycle. To reduce these impacts, the ‘Green Concrete’ concept is at focal point of research in the construction industry. The advantage of resource conservation of ‘Green concrete’s is evident from usage of industrial by-products like fly ash, blast furnace slag, silica fume etc. as alternative binder materials and recycled wastes like construction and demolished waste and other industrial wastes as aggregate fillers. However, the quantification of environmental impact of such concretes in terms of most crucial emissions, like CO2 emissions in an objective way would confirm the eco-friendly face of ‘Green concrete’. Life cycle assessment (LCA) is one of the most trusted tools to arrive at carbon score of such green concrete. This paper presents a step-by-step procedure of estimation of carbon footprint of a green concrete considering all possible phases of the life cycle of concrete including the post use phase. The conclusive findings from available literature for different types of ‘Green concrete’ are also presented to reflect the environmental advantage/disadvantage. The effect of system boundary, carbon uptake and allocation of impact are also discussed with reference to the results available in the literature.

The role of data variability and uncertainty in the probability of mitigating environmental impacts from cement and concrete

Concrete is the most produced manmade material globally. This widespread production results in significant anthropogenic environmental impacts, the awareness of which has spurred advances in material development to lower these burdens. However, proposed changes are often not assessed in the context of the data variability and uncertainty inherent in the environmental impact quantification methods employed. As such, the probability that any suggested strategy will result in a desired effect is not addressed. This work aims to quantitatively examine data variability, an inherent characteristic of elements in supply chains, and data uncertainty, a function of data quality for the system being modeled, in assessments of greenhouse gas (GHG) and air pollutant emissions from concrete production. Data variability is determined through ranges in requisite input values from the literature; data uncertainty is assessed through application of an established pedigree matrix method. Statistical analysis of the emissions from concrete production incorporating sources of variability and uncertainty are examined through Monte Carlo simulations. Concrete mixtures, representing a feasible structural concrete for use in California infrastructure and three alternative mixtures are assessed, as are three GHG emissions mitigation strategies, namely, a change in thermal energy fuel mix, a change in electricity grid, and use of carbon capture and storage. The distributions of emissions derived through statistical analyses are used to examine the probability of efficacy of these strategies, as well as potential co-benefits on air emissions. Results show each constituent change and each mitigation strategy considered would lead to a reduction in GHG emissions if only mean values are compared; however, the probability of these reductions varies. These findings suggest mitigation efforts may not be as definitive as current assessments suggest. Results indicate the importance of using statistical methods to target desirable mitigation efforts in the environmental impacts from concrete production.

BIM-DLCA: An integrated dynamic environmental impact assessment model for buildings

Life cycle assessment (LCA) is an important and widely used environmental impact quantification methodology. Recently, temporal variations have generated renewed interests in LCA, with dynamic LCA (DLCA) becoming a new research trend. Traditional data collection approaches are considerably time and effort intensive, with major challenges associated with the acquisition of high quality data that are available. This study integrates building information modeling (BIM) with DLCA to develop a new assessment model for buildings. It follows the basic LCA paradigm and includes five parts: goal and scope definition, BIM module, dynamic database, dynamic assessment, and interpretation. In the BIM-DLCA model, BIM was used to extract material information and the construction schedule. A number of analysis software and simulation tools were used to quantify the temporal elementary flows throughout the lifecycle of the building. Various forms of dynamic data were aggregated to create a database that supports dynamic assessment. A case study was used to testify the BIM-DLCA model and the case study's outcomes indicate that BIM has the potential to simplify data collection process and support DLCA. The proposed BIM-DLCA model is operable in practice. With the rapid development of digitalization and intelligence, the proposed BIM-DLCA model lays an important foundation for future assessment studies and promotes smart LCA.

Sustainability assessment of levulinic acid and succinic acid production from empty fruit bunch

Empty fruit bunch (EFB) generated as waste in plantation mill activities in Malaysia is a potential biomass feedstock of biorefinery for fuels and chemicals production. Levulinic acid and succinic acid, two out of 12 chemical building blocks identified by Department of Energy (DOE) to be used in synthesis of high-value materials, can be produced from biochemical conversion of the EFB. This paper evaluates sustainability assessment of EFB to levulinic acid and succinic acid. The assessments include net present value (NPV), global warming potential (GWP), and Hazard identification and ranking (HIRA) to cater for economic, environment, and safety performances, respectively. The results show that the levulinic acid production is more economically attractive than succinic acid production. The environmental impact quantification reveals that the levulinic acid has lower GWP score of 6.3 kgCO2-eq/kg levulinic acid than succinic acid with 11.2 kgCO2-eq/kg succinic acid. Meanwhile, the succinic acid production is inherently safer than levulinic acid production due to its less severe operating conditions.

Environmental benefits of construction and demolition debris recycling: Evidence from an Indian case study using life cycle assessment

The adversarial effects of construction and demolition (C&D) waste on the environment are on the increase. While materials such as metals, wood, glass and plastics are segregated and diverted for reuse/recycling, C&D debris consisting of concrete, bricks and tiles are landfilled in most of the countries. LCA studies have indicated a clear preference for recycling. However, it has been inferred that the environmental credits obtained in these studies were mainly from recycling of metals and wood and studies focusing on environmental impacts/benefits evaluation of C&D debris recycling is limited. This is particularly relevant in the cases of developing countries like India, where C&D debris forms a bulk of C&D waste generation. Therefore, this paper evaluates the environmental impacts of four different scenarios for managing C&D debris comprising the present (S1) and future (S2) landfilling options and recycling options without transfer stations (S3) and with transfer stations (S4). LCA according to ISO methodology is performed based on locally sourced data supplemented with Ecoinvent database. IMPACT 2002+ impact assessment method has been applied for environmental impact quantification using SimaPro software. Landfilling of C&D debris generates environmental impacts, and recycling scenarios generate environmental benefits in all 15 impact categories. Single score values of landfilling scenarios are 1.83 mPt (S1) and 2.78 mpt (S2) and that of C&D debris recycling are −2.56 mPt (S3) and −1.91 mPt (S4). The robustness of the results was shown through sensitivity analysis. Recycling remains beneficial compared to landfilling as long as the diesel and electricity consumption of C&D debris recycling facility remains less than 475% of the current consumption. Furthermore, even if the transportation distance from quarry to crushing unit is reduced to zero, recycling still remains a better alternative. The merit of considering the future landfilling scenario in the decision making has been discussed since the challenges that might be encountered in setting up new landfills are underestimated. The implications of the findings and their relevance to urban local bodies have also been discussed to help policymakers take informed decisions while facing challenges of managing C&D debris.

The functional and environmental performance of mixed cathode ray tubes and recycled glass as partial replacement for cement in concrete

Concrete is one of the most abundantly produced and commonly used construction materials in the world. The production of cement—the main binder in concrete—is energy-intensive, using roughly ten times the national average ratio for energy to gross output of goods and services. Given the high demand for concrete globally and the amount of energy used to produce cement, it is worthwhile to find lower embodied-energy materials to partially replace cement to improve the environmental impacts of concrete without decreasing the concrete performance. One such potential cement replacement is the panel glass found in discarded cathode-ray tubes (CRTs). It is against this backdrop that this study aimed to investigate the technical feasibility and the environmental impacts of using a novel blend of recycled glass and CRT panel glass as pozzolanic material for replacing a portion of ordinary portland cement (OPC) in concrete. Additionally, this study simultaneously looked at the concrete functional performance and environmental impact, and the study was performed at an industrial scale using existing production infrastructure, production volumes, standardized testing, and a life-cycle assessment (LCA) to support the functional testing and environmental impact quantification. Results show that the novel blend of glass met the required performance standards, and when it was blended with cement, the mixture produced concrete with similar or improved functional performance and significantly reduced environmental impacts across all examined impact categories. Future work is needed to examine the additional benefits of diverting CRTs from their current end-of-life pathways and de-risking CRT storage.

Environmental Sustainability of Niobium Recycling: The Case of the Automotive Industry

The recycling of scrap is one of the common approaches aiming at reduction of mining-based production of critical metals and mitigation of their supply risk as well as processing-related environmental impact. The number of currently available end-of-life vehicles (ELVs) indicates—significant potential for critical metals recycling, especially niobium (Nb). Therefore, the quantification of environmental impact of niobium recovery starts to be an important issue in assessment of sustainability of large-scale recycling processes. In this paper, we assess energy consumption and greenhouse gas (GHG) emissions in individual stages of niobium supply chain in the automotive industry over the period 2010–2050. The different stages including mining, production and recycling are analyzed using dynamic simulation. The results show the majority of the consumed energy (45% of energy demand in niobium supply chain) is used in the primary production stage. This stage also contributes to 72% of total gas emissions of supply chain over the period 2010–2050. Mining of niobium consumes up to 36% of energy and generates ca. 21% of GHG emissions. While, in recycling stage, the secondary production of niobium requires 19% of supply chain energy and generates 7% of gas emissions. The detailed calculations show that recycling of niobium could save around 133–161 m GJ energy between 2010 and 2050. The recycling would also contribute to the reduction of 44–53 mt CO2-eq in the same period. It shows around 18% reduction of annual emissions between 2010 and 2050 thanks to reuse of niobium in secondary production rather than primary production.

Application of Eco-Design and Life Cycle Assessment Standards for Environmental Impact Reduction of an Industrial Product

Eco-design is included within the framework of the standard for “Environmental management systems—Guidelines for incorporating Eco-design” (ISO 14006:2011). Eco-design process, as defined in standard, has six steps: (i) Specify product functions; (ii) Environmental assessment of products; (iii) Strategies of improvement; (iv) Environmental objectives; (v) Product specification; and (vi) Technical solutions. Step (ii), determination of the stage or process of the product life cycle that has the highest environmental impact; this is perhaps the most controversial step because the standard does not specify which tool should be used. This lack of specification has generated some distrust with regard to eco-design, hindering its development. In order to make a trustworthy eco-design, Life Cycle Assessment (LCA) should be applied as a tool for environmental impact quantification. The main objective of this work is to apply standardised eco-design methodology for the reduction of the environmental impact of an industrial product in Spain using LCA as a tool for the environmental product assessment. LCA standardised process (ISO 14040,14044:2006) is included in the eco-design process. A glass container intended for cough syrup delivery has been selected as an industrial product to be eco-designed. Following the methodology described, the overall normalised impact decreased 35.1% when a PET container substituted a glass container. Environmental impacts have been reduced following standardised eco-design and LCA methodologies, serving as an example to industry and administration regarding how to eco-design with the confidence of obtaining reliable results.

Techno-economic analysis and environmental impact assessment of lignocellulosic lactic acid production

Lignocellulosic Lactic acid (LA) production is considered for the diversification and value addition to an existing sugar industry by annexing a biorefinery using lignocellulosic residues, sugarcane bagasse and leaves (SCBL). In biorefinery, the hemicellulose (C5 sugars) and cellulose (C6 sugars), resulting from lignocellulosic matrix fractionation, can be converted into building block chemicals and fuels by biotechnological or chemical pathways. To co-produce LA with other fuels and chemicals from SCBL, it is important to determine whether LA production from C5 or C6 sugars should be preferred, based on economic viability and environmental impacts. In this paper we developed six process scenarios for LA production from either the hemicellulose liquid fraction and cellu-lignin solid fractions of SCBL after steam explosion pretreatment, based on 200tonne/day of SCBL feed. The lignocellulose fraction not used for LA production will be used for integrated production of other marketable products in a biorefinery. Scenarios S1, S3, & S5 use the hemicellulose liquid fraction as feed for LA production, while scenarios S2, S4, & S6 use the cellu-lignin solid fraction. Two scenarios, S1 & S2, use Ca(OH)2 as neutralizer in fermentation, resulting in co-production of gypsum as solid waste, scenarios S3 and S4 use an isolated acid-tolerant thermophilic bacteria, Bacillus coagulans isolates for fermentation, thus avoiding the need for neutralization, while Scenarios S5 and S6 use Mg(OH)2 as neutralizer in fermentation, with recycling of Mg(OH)2. LA was separated and purified from the fermentation broth by reactive distillation. The six process scenarios were modeled and simulated by Aspen Plus® with the resulting mass & energy balance and equipment-sizing used as inputs to economic analysis and environmental impact assessment. Standard life cycle assessment (LCA) method is used in SimaPro® for environmental impact quantification. Cellulose based processes have larger LA production rates than the hemicellulose based processes, for the same flow rate of SCBL, which impacts on their total capital investment (TCI), operating cost (OPEX) and revenues for the same process technology. Increases of 7.08%, 58.13%, 12.04% and 60% in TCI, revenue, OPEX and LA production rates, respectively were observed in moving from S1 to S2. Similar increases of 10.88%, 86.52%, 18.52% and 91.07% in TCI, revenue, OPEX and LA production respectively in moving from S3 to S4. An increment of 10.08%, 61.57%, 18.32% and 63.90% in TCI, revenue, OPEX and LA production respectively was also found in moving from S5 to S6. Scenarios S3 and S4 are found to have lower TCI and OPEX but their production rate is low as well making them economically less attractive with internal rate of return (IRR) of 9.13% and 15.23% respectively. While S1 and S2 have IRR of 13.11% and 19.4% respectively and yet higher TCI and OPEX. S5 and S6 have the highest IRR, 14.72% and 21.28% respectively with TCI and OPEX of way below their equivalent scenarios S1 and S2 respectively. From the environmental point of view S1 and S2 are found to be environmentally less friendly with higher environmental burdens in almost all impact categories considered. Gypsum free scenarios, S5 and S6, are found to be the most attractive processes from both economic and environmental points of view, with S6 being superior than S5.

Methods for global sensitivity analysis in life cycle assessment

PurposeInput parameters required to quantify environmental impact in life cycle assessment (LCA) can be uncertain due to e.g. temporal variability or unknowns about the true value of emission factors. Uncertainty of environmental impact can be analysed by means of a global sensitivity analysis to gain more insight into output variance. This study aimed to (1) give insight into and (2) compare methods for global sensitivity analysis in life cycle assessment, with a focus on the inventory stage.MethodsFive methods that quantify the contribution to output variance were evaluated: squared standardized regression coefficient, squared Spearman correlation coefficient, key issue analysis, Sobol’ indices and random balance design. To be able to compare the performance of global sensitivity methods, two case studies were constructed: one small hypothetical case study describing electricity production that is sensitive to a small change in the input parameters and a large case study describing a production system of a northeast Atlantic fishery. Input parameters with relative small and large input uncertainties were constructed. The comparison of the sensitivity methods was based on four aspects: (I) sampling design, (II) output variance, (III) explained variance and (IV) contribution to output variance of individual input parameters.Results and discussionThe evaluation of the sampling design (I) relates to the computational effort of a sensitivity method. Key issue analysis does not make use of sampling and was fastest, whereas the Sobol’ method had to generate two sampling matrices and, therefore, was slowest. The total output variance (II) resulted in approximately the same output variance for each method, except for key issue analysis, which underestimated the variance especially for high input uncertainties. The explained variance (III) and contribution to variance (IV) for small input uncertainties were optimally quantified by the squared standardized regression coefficients and the main Sobol’ index. For large input uncertainties, Spearman correlation coefficients and the Sobol’ indices performed best. The comparison, however, was based on two case studies only.ConclusionsMost methods for global sensitivity analysis performed equally well, especially for relatively small input uncertainties. When restricted to the assumptions that quantification of environmental impact in LCAs behaves linearly, squared standardized regression coefficients, squared Spearman correlation coefficients, Sobol’ indices or key issue analysis can be used for global sensitivity analysis. The choice for one of the methods depends on the available data, the magnitude of the uncertainties of data and the aim of the study.

Environmental assessment of municipal wastewater discharges: a comparative study of evaluation methods

Wastewater treatment plants produce high environmental impacts on receiving water bodies and pose economic burdens on municipalities or industrial facilities. Their overall operational costs and achieved effluent quality depend very much on the influent type, presence of priority pollutants, treatment technology and required effluent quality (for discharge or for recycle/reuse). Life cycle assessment (LCA), environmental impact quantification (EIQ) and water footprint (WF) are important instruments for sustainability assessments applied for products, production and consumption evaluations in connection with natural resources depletion and pollution threats. This study focuses on the environmental assessment of a municipal wastewater treatment plant (MWWTP) discharges by means of these three evaluation methods with the purpose to understand their (methodological) weak and strong points in capturing the impacts. Such a comparative analysis is necessary to understand how the (individual) advantages provided by each of these instruments can be complimentarily used to improve an assessment framework for various stakeholders concerned with water use cycle management (regional water operators, water management authority, public authorities, research entities, societal organizations, etc.). The three assessment methodologies (LCA, EIQ, WF) are presented, implemented and critically analysed based on a unitary set of data concerning the MWWTP of Iasi city (a municipality of approx. 300,000 inhabitants situated in the North Eastern region of Romania), the wastewater and river water quality indicators as well as all the other relevant data being collected for the year 2012. Although the three methodologies have different principles for environmental impact quantification, the results have shown that most impacts induced to surface waters due to Iasi MWWTP effluents are given by the nutrients (nitrogen and phosphorous compounds), which could induce an eutrophication impact, and to a lesser extent by pollutants responsible for toxicity impacts (such as heavy metals). Based on the results of this comparative study, a critical analysis of these three methods was realized by considering the data requirements, their development and integration status. Furthermore, the strong and weak points that are relevant for each method implementation and their subsequent use by decision-makers and Water Authorities are discussed, in the context of legislative requirements (including the Water Framework Directive), actual development of regional water operators and stakeholders' interests.

CASCADE CROPS: AN ALTERNATIVE SOLUTION FOR INCREASING SUSTAINABILITY OF GREENHOUSE TOMATO CROPS IN MEDITERRANEAN ZONE

Nitrate pollution due to excessive N fertirrigation in greenhouse tomato production is a persisting environmental concern in the Mediterranean region. Closed or re-circulating hydroponic systems can significantly reduce fertilizer run-off but not eliminate it, and the spent nutrient solution has to be ultimately collected and treated at the end of the crop cycle. Also, closed systems involve greater installation and running costs, need a high degree of automation and technical skill, and their economic viability is a question of debate in southern Europe horticulture. As a consequence, the majority of the high-value horticultural production in Mediterranean countries is done using 'open' systems. The aim of this paper is to present an alternative way to reduce fertilizer use and, hence, reduce the pollution potential of leachate in soilless crops by collecting and re-using it for a second greenhouse crop. Avoided environmental impact quantification was performed by using LCA tool. Results showed a slight decrease in yield for the soil crop, in comparison with the soilless system, but marketable production (15 kg m-2) for this treatment was higher than the average production of soil grown tomatoes (12 kg m-2). Nitrogen balance for the two combined systems showed an important decrease in N leachate (more than 60% referred to the soilless system). The adoption of the cascade crop system reduced environmental impact for climate change category by 21%, but increased eutrophication category by 10% because of the yield reduction. Further research will be oriented to look for the optimum management of lixiviates combined with organic and/or mineral fertilizers for these cascade crops.

Quantification of environmental impact and ecological sustainability for textile fibres

This paper reports the development of a unique model to quantify the environmental impact made by various textile fibres and also to position them in terms of ecological sustainability. A wide range of textile fibres and the major contributing factors in terms of environmental impact during manufacturing phase (starting from growth/extraction stage to production of a useful fibre which can be spun) have been selected. Amount of oxygen produced/carbon-di-oxide absorbed consequently contributing to off-set global warming during the production phase of a fibre, utilisation of renewable resources, land use, usage of fertilisers and pesticides, fibre recyclability and biodegradability of chosen fibres have been considered. Amount of energy consumed, quantity of water utilised and amount of green house gases emitted have been considered for life cycle inventory (LCI) and a life cycle impact assessment (LCIA) study has been accomplished to derive certain impact categories pertaining to the damage created to human health, ecosystem quality and resources, which will elucidate the characteristics of ecological sustainability. A scoring system based on the above mentioned factors which predominantly determine ecological sustainability has been framed, from which an Environmental Impact index (EI) has been developed. Further, an Ecological Sustainability Index (ESI) has been derived from EI values for the chosen fibres. According to this system, organic cotton is the most and acrylic is the least preferred fibre. A sensitivity study has been done to check the robustness of the developed model and the results of the same have been reported.