1,721,522 research outputs found
Indoor air quality in waste treatment: Environmental issue and biotechnology application for air pollution containment, a case study
Full text linkA proper integrated management of municipal waste analyzes the entire life cycle of waste, from cradle to grave, i.e. the final stage of disposal or recycling, through which waste come back as a resource, as required by Waste European Directive. In this perspective, every possible impact factor should be taken into account and, therefore, air quality and odor control have to be addressed as crucial elements for sustainable waste management, as directly affecting quality of life of both workers and people living in the surroundings of waste treatment facilities. While the issue is generally regarded as a major concern in presence of incinerators (for air pollution control) and landfill (for odor, mainly), it is usually neglected when segregated dry waste treatment is involved, but it remains an element of concern for population and, therefore, public stakeholders. A modern segregated waste treatment plant, already compliant with regulations requirements regarding indoor air quality and human health, was taken as a case study to prove the effectiveness of a biotechnological treatment for air pollution and odor control. The system applied is based on stand-alone bio-oxidizers that provide internal air-mixing within the facility and capture particulates and gases by attracting them to a clean air zone generated by its action. In this paper, only the preliminary phase of application for the system is presented. It was preceded by a completion of analysis of air quality baseline, collected by a Wireless Sensor Network, which have been compared to the following five months of system activity, showing a consistent effectiveness in air pollutant containment and abatement. These results found confirmation in parallel independent laboratory analysis which showed comparable abatement trends. A comparison with a traditional biofiltration case study marked the great opportunity offered by the bioreactors' system implemented in an overall indoor air quality perspective
Assessing the externalities of a waste management system via life cycle costing: The case study of the Emilia-Romagna Region (Italy)
No full textEffective and efficient urban waste management systems (WMSs) are a cornerstone for a sustainable society. Life cycle costing (LCC) provides a useful framework for the joint analysis of economic and environmental impacts of a WMS, by considering both financial and external costs. The present study applies the methodology of societal LCC to the WMS of the Italian region of Emilia-Romagna to provide a case study on how the available information on waste flows and budget costs of a real WMS can be used to obtain an estimate of the total cost of waste management, including externalities.
The results evidence that the main source of negative externality in the analyzed WMS is the transportation of waste, with only a minor role of external burdens due to incinerators and landfills. However, the positive externality resulting from recycling more than compensates those impacts, leading to a net external benefit associated to the WMS.
The contribution of both uncertain unit external costs and environmental benefits imputable to recycled materials to the overall uncertainty of the result is systematically investigated by parametric uncertainty analysis. The most critical parameters in determining the sensitivity of the result are the monetary values attributed to primary energy consumption and CO2 emissions, together with assumptions on energy savings related to recycling.
Eventually, it is shown how the developed LCC model can be used as decision-support tool to preliminarily investigate the implications of alternative management options on the financial and external costs of the WMS
Municipal solid waste collection systems: An indicator to assess the reusability of products
No full textThe paper illustrates a model to support waste management (WM) operators of municipal solid waste (MSW) services. This study proposes a framework to evaluate the potential of preparation for reuse (PfR) as strategy to jointly decrease social, environmental and economic impacts and meet the legal targets on waste management. As general indicators to evaluate the reusability of products do not exist yet, the aim of this study is the definition of a comprehensive indicator, which may be calculated for each product category by waste collection operators. The proposed reusability indicator includes one coefficient evaluating the potential for reuse, and three impact indicators for the assessment of social, environmental and economic performances. The indicator can be calculated by using real data, gathered by the waste collection operators in collaboration with reuse centres and referred to previous years. Hence, the proposed methodology allows waste collection operators to evaluate the potential consequences of the reuse strategy on their MSW collection system to monitor and disclose to public the impacts related to reuse activities, facilitating the achievement of sustainability in the WM sector
ENVIRONMENTAL FOOTPRINT IN THE PRODUCTION OF RECYCLED WOOL
No full textWe computed the Product Environmental Footprint (PEF) to identify the environmental performance of recycled wool by means of data belonging to a real case study in Italy. First, we analyzed inventory data quality by computing the data quality rating (DQR) index, according to the criteria provided by the PEF protocol. Quality of specific and generic data (selected from the Ecoinvent database) was evaluated as excellent and good, respectively. We then quantified the impacts related to each relevant production process via Life Cycle Assessment (LCA). Specifically, we identified four main processes involved in the production of recycled wool for the selected case study: (i) clippings supply, (ii) clippings preparation, (iii) ragging, and (iv) dyeing. In the production of recycled wool, the rate of incoming materials subject to dyeing decreases to about 40%. Nevertheless, LCA revealed that this process is the most critical due to the high energy consumption and chemical substances employed. This result was confirmed by further analysis based on the Eco-indicator approach and the single point eco-indicator score. In particular, we found that environmental impacts associated with the production of recycled wool are mainly related to the following categories: (i) depletion of abiotic resources, (ii) inorganic particles released into the air, (iii) climate change, and (iv) human toxicity. We quantified that the contribution of the dyeing process to the relevant impact categories is higher than 75%. These results revealed how the use of recycled materials strongly increases the environmental performance associated with wool production, reducing the impact of the most environmental demanding processes
Solids-liquid separation and solar drying of palm oil mill wastewater sludge: Potential for sludge reuse
Full text linkIn this study, empty palm fruit bunchfibre was used for solids-liquid separation of palm oil mill wastewater andthe sludge was sun-dried for potential uses as soil conditioner or solid fuel. Thefibre was manually compressedinto a wooden mould to obtain afibre bulk density of 70 kg/m3. A composite wastewater sample was pouredevenly over the surface of thefibre. The wet solids were sun-dried for 14 days to achieve a moisture content of<10%. The mass of each mould was determined daily after sunset throughout the drying period. The nutrientscontent and calorific value of the dried sludge were determined using standard methods. The solids-liquid sep-aration process was able to achieve>99% solids and up to 65% COD removal. Analysis of the dried sludgeshowed nutrients content (% of dry weight) of 0.84 for total nitrogen, 0.15 for phosphorus and 0.49 for potassium.The mean calorific value of the dried sludge was 17.1 MJ/kg. The results show the potential of sun-dried palm oilmill wastewater sludge for use as sustainable soil conditioner or solid fuel. The effluent from the solids-liquidseparation must be given additional treatment as it may still contain harmful constituents
Door-to-door waste collection: a framework for the socio – Economic evaluation and ergonomics optimisation
No full textWaste collection is the first step of waste management, and its characteristics impact workers’ health and safety. Arising out of the challenge for waste collection operators to design sustainable systems of work, the authors review the literature on ergonomics and socio-economic sustainability and design a theoretical framework for assessing the sustainability of waste collection. The framework quantitatively assess the impact of the door-to-door collection system on the health and safety of the workers to provide indications to waste collection operators on how the load carried by workers can be minimised and the economic and social sustainability can be improved. As a case study, this paper investigates the musculoskeletal disorders derived from the manual material handling of waste containers affecting the workers in charge of door-to-door sorted collection of paper waste with the goal of optimizing the workers well-being and overall waste collection system performance The research study was conducted in collaboration with a company which operates in solid waste collection for Italian municipalities. For this purpose, the ergo-quality level of two paper waste collection systems is evaluated. For each system, ten scenarios of door-to-door paper waste collection are considered. The analysis is complemented by an economic analysis, which estimates the costs associated with the collection system under consideration, and a social life-cycle assessment. Results suggest that using 120-litres capacity bins would effectively improve ergonomics and optimise the costs of the investigated activity. More specifically, due to mechanised collection, the more limited number of lifting and carrying operations would expose the workers to lower ergonomic risk
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