Life Cycle Assessment as Support Tool for Development of Novel Polyelectrolyte Materials Used for Wastewater Treatment

This life cycle assessment (LCA) study focused on comparing the environmental performances of two types of synthesis strategies for polyethyleneimine (PEI) coated silica particles (organic/inorganic composites). The classic layer-by-layer and the new approach (one-pot coacervate deposition) were the two synthesis routes that were tested for cadmium ions removal from aqueous solutions by adsorption in equilibrium conditions. Data from the laboratory scale experiments for materials synthesis, testing, and regeneration, were then fed into a life cycle assessment study so that the types and values of environmental impacts associated with these processes could be calculated. Additionally, three eco-design strategies based on material substitution were investigated. The results point out that the one-pot coacervate synthesis route has considerably lower environmental impacts than the layer-by-layer technique. From an LCA methodology point of view, it is important to consider material technical performances when defining the functional unit. From a wider perspective, this research is important as it demonstrates the usefulness of LCA and scenario analysis as environmental support tools for material developers because they highlight environmental hotspots and point out the environmental improvement possibilities from the very early stages of material development

Aging Passenger Car Fleet Structure, Dynamics, and Environmental Performance Evaluation at the Regional Level by Life Cycle Assessment

The need to limit climate change and to improve air quality clearly is a driver for technology and policy changes in the transport sector. This study investigates how this technology shift at the European level ages personal car fleets at the regional level in Romania through second-hand imports. It also asks what how the situation will evolve in terms of environmental impacts. The study presents an in-depth assessment of the environmental performance and evolution of the passenger car fleet in Iasi County (Romania). The analysis is based on the car fleet structure and dynamic statistics, and uses the Copert 5.5 model to estimate the specific use-phase emissions, which subsequently are used as input data into an LCA analysis. The study considers three scenarios regarding fleet evolution and environmental performance, and focuses solely on the use phase of passenger cars. It models exhaust emissions in various driving situations (rural, urban, hot-cold operation, and peak-offpeak traffic values) and considers the current environmental performance classes and age of vehicles in the fleet. The results show that by considering these vehicle performance aspects, impacts are better represented. The no-change scenario would lead to a 2.5 times increase of global warming impacts by 2035 as compared to 2020, while by limiting the import of used cars and increasing the share of electric and hybrid vehicles would lead to mitigating these impacts

Emerging pollutants removal through advanced drinking water treatment: A review on processes and environmental performances assessment

The presence of emerging pollutants in the aquatic environment in relatively small concentrations and the fact that they cannot be removed by conventional water/wastewater treatment processes bring new challenges in terms of adequate selection of technologies from the technical, economical and environmental points of view. Generally, literature discusses emerging pollutants’ removal at significant concentrations (such as those in wastewater), while few studies consider their low concentrations occurring in raw water. This study presents a comprehensive review of the research efforts related to the occurrence, fate, health effects and impacts of emerging pollutants on advanced drinking water treatment and the environmental performance evaluation of different technological options, with a focus on pilot and full-scale installations. All presented case studies consider pollutants removed, process conditions and removal efficiencies, thus making possible comparisons between membrane processes, advanced oxidation processes and adsorption on activated carbon and other materials. The study is completed by an analysis of the environmental assessment instruments (life cycle assessment, carbon, water footprints, other type of assessments) that may be used for selecting sustainable advanced drinking water treatment processes able to remove emerging pollutants. This paper critically reviews the main research topics concerning emerging pollutants: classification, legislative framework, up-to-date removal processes and their environmental performances assessment, to offer a comprehensive analysis of the strategic issues that may constitute future research directions for sustainable water supply

Chicken Manure Valorisation by Forced Aeration In-Vessel Composting at Laboratory Scale

<p>Intensive rearing of different animals has led to significant amounts of farming animal derived wastes, such as chicken manure, an important biodegradable waste that is still frequently applied in direct land fertilization as a method of disposal. Unfortunately, this is not a sustainable treatment option for chicken manure due to its intrinsic properties. In line with the waste management hierarchy options and with circular economy principles, chicken manure valorisation is possible after biological or chemical treatment, the first being even more desirable because it mimics the natural cycles. However, various materials must be added to the chicken manure to make susceptible to biodegradation. This study proposes the experimental laboratory-scale investigation of an in-vessel forced aeration process applied for the treatment and valorisation of chicken manure. The most suitable bulking agent out of 4 materials (sawdust, wheat straw, lignite and charcoal) and the various C:N ratio in waste-bulking agent mixtures were investigated. The results indicated that lignite is the most suitable bulking material, while a C:N ratio of a chicken-manure lignite mix of 10:6 is considered to give the best composting results.</p&gt

Instruments for integrated water resources management: Water quality modeling for sustainable wastewater management

This study presents the development and use of a hydraulic-coupled water quality model for the simulation of Biochemical Oxygen Demand (BOD) concentrations in the Bahlui River, a small river located in northeastern Romania. This river experiences the typical pollution problems for many Romanian water bodies: heavy pollution from both diffuse and point sources, low connectivity to wastewater systems in rural areas and moderate removal of pollutants in municipal wastewater treatment plants. The model was used to generate an image of the BOD regime of the Bahlui River, and to simulate two wastewater infrastructure development scenarios: the first one considered the improvement of the municipal wastewater treatment facilities, and the second scenario considered that all the point sources along the river discharge BOD- containing wastewaters within appropriate limits. Simulation results for the two scenarios indicated that upgrading the wastewater treatment infrastructure does not necessarily lead to major improvements in river quality, and subsequently, other wastewater management options have to be considered to achieve the Water Framework Directive objectives. The study shows how even with limited data a useful model can be developed to assess the contribution of different sources and evaluate strategies for water quality improvement. The application of models is rather new in Romanian water resources management but can help stakeholders to get more insight on the system behavior and find integrated and effective solution

Sustainability assessment of reactive capping alternatives for the remediation of contaminated marine sediments

The article deals with an original approach, based on sustainability, to select the best reactive capping alternatives for the remediation of contaminated sediments from Mar Piccolo (Italy), one of the most polluted marine ecosystems in Europe. Experimental tests were conducted to assess the capping effectiveness in contaminant sequestration and degradation. The environmental impacts were evaluated by using Life Cycle Assessment, while Multi Criteria Decision Analysis was implemented to consider the stakeholders’ view as well as to identify the best capping solution. The results indicated that the pollutants concentrations in the seawater increase in time without capping, involving possible risks to Mar Piccolo environment. Instead, after capping placement, environmental standards for seawater were always respected. Capping with Activated Carbon and Zero Valent Iron is the best solution for both chemical isolation (efficiency: 95%) and degradation aid (efficiency: 40%). Zero Valent Iron has higher environmental impacts, and it is closely followed by activated carbon and organoclay. The sustainability assessment shows how both the Reactive Permeable Mats with 3 kg/m2 Activated Carbon and Reactive Granular Materials with 5% Activated Carbon are the best solutions for Mar Piccolo remediation. The proposed methodology can be a step towards more sustainable decision making for contaminated sediments remediation

Does PET trays sorting affect the sustainability of plastic waste? An LCA and cost-revenue approach

Currently, the management of polyethylene terephthalate (PET) trays waste is still challenging since this packaging affects the consolidate recycling of PET bottles. It is important to separate PET trays from the PET bottle waste stream to avoid its contamination during recycling process and to recover a higher amount of PET. Hence, the present study aims to evaluate the environmental (by means of Life Cycle Assessment, LCA) and economic sustainability of sorting PET trays from the plastic waste streams selected by a Material Recovery Facility (MRF). For this scope, the case of a MRF in Molfetta (Southern Italy) was chosen as reference, and different scenarios have been evaluated by assuming different schemes of manual and/or automated PET trays sorting. The alternative scenarios did not achieve very pronounced environmental benefits over the reference case. Upgraded scenarios resulted in overall environmental impacts approx. 10 % lower as compared to the current scenario, with the exception of the climate and ozone depletion categories where differences in impacts were much higher. From an economic point of view, the upgraded scenarios achieved slightly lower costs (<2 %) than the current one. Electricity or labour costs were necessary in upgraded scenarios, but in this way fines for PET trays contamination in PET streams for recycling were avoided. Implementing any of the technology upgrade scenarios is then environmentally and economically viable, when the PET sorting scheme is performed in appropriate output streams through optical sorting

LIFE CYCLE ASSESSMENT OF A DRINKING WATER PRODUCTION SYSTEM

The main goal of water treatment is to avoid human health risks and to provide sufficient and good quality water for drinking, industrial purposes, and other economic activities by removing chemical and biological contaminants through water treatment processes. However, these processes require increasing efforts in terms of technology, chemicals and energy inputs, which translates to increased secondary environmental impacts and increased water production costs. The objective of the study is to evaluate the drinking water treatment (DWT) system in Iasi City (Romania), by means of life cycle assessment and to identify and characterize the environmental impacts, to determine the weak points of drinking water production processes. Iasi City is the most developed urban centre from Moldova Region in the North Eastern region of Romania and has a DWT system providing water in accordance with European standards. The DWT system process comprises the following stages: coagulation/flocculation with ferric chloride (or polyacrylamide and powdered activated carbon) coupled with pre-oxidation (injection of chlorine dioxide), followed by sedimentation in radial basins, pH correction with calcium hydroxide, rapid filtration on sand filters, slow filtration on granular activated carbon (GAC) filters and followed by final disinfection with chlorine gas. In this study a life cycle analysis has been applied to assess the environmental performance of Iasi DWTP for 1 m3 of potable water produced, considering the impact generated by energy consumption, technologies and reagents used. The electricity required by the different treatment stages has been accounted for the entire DWT plant, each equipment and water treatment parameters being monitored and controlled through a SCADA software. The main contributors to impact in most of the categories are the electricity consumption and the iron chloride production used in coagulation/flocculation step. The most important impact categories are the freshwater eutrophication and the freshwater and marine ecotoxicity, and the most important contributors remain electricity and iron chloride usage. The level of detail obtained for the inventory and the impact assessment steps may be used as reference for future LCA studies, analysing other water treatment plants since the climate, technological, cultural and socio-economical differences clearly define the particularities of a DWT in any context and region

A life cycle assessment study on the stabilization/solidification treatment processes for contaminated marine sediments

Contaminated marine sediment management strategies involves in situ and ex situ options for preventing pollutants from re-entering the water column, thus becoming available to benthic organisms and subsequently entering aquatic food chains. These pollution abatement strategies can cause significant secondary environmental impacts which in some cases have been considered to be even higher than the primary ones. This study aims at identifying and quantifying through life cycle assessment (LCA) the environmental impacts of the application of Stabilization/Solidification (S/S) options for the remediation of contaminated marine sediments from the Mar Piccolo in Taranto (Southern Italy). The analysis considers all the stages involved in marine sediments processing (dredging, transport, storage, treatment, safe disposal of the treated sediments) but focuses on several S/S options (4 S/S mixes with cement and 4 mixes with lime). These S/S options were tested at lab scale with different results in immobilizing heavy metals and organic pollutants. The LCA suggests that the ex-situ treatment could contribute to improving the current situation and that the marine sediments S/S operation generates a complex environmental profile which is dominated by the treatment phase, which in turn shows that optimization of this stage could lower these impacts