Belmira Neto

Modelling the environmental impact of an aluminium pressure die casting plant and options for control

This study describes a model (MIKADO) to analyse options to reduce the environmental impact of aluminium die casting. This model will take a company perspective, so that it can be used as a decision-support tool for the environmental management of a plant. MIKADO can be used to perform scenario analyses to analyse the impact on the environment of different strategies, while taking into account both economical and ecological consequences of decision-making. The MIKADO approach is based on relevant parts of Life Cycle Assessment, environmental systems management and Multi-criteria Analysis. One of the strengths of MIKADO is the integrated approach that it takes in analysing, simultaneously, a set of eight environmental problems, including: human toxicity, abiotic depletion, global warming, solid waste production, acidification, terrestrial ecotoxicity, photochemical ozone formation and aquatic toxicity, caused by the aluminium die casting plant. The model is developed for and applied to a specific aluminium die casting plant supplying car manufacturers with aluminium die casting products. We present model results for a reference case, indicating that most of the environmental impact of the plant is associated with releases of compounds during the melting and casting of alloy, as well as with the use of natural gas. Finally, we present results of a partial sensitivity analysis, indicating the sensitivity of the model to changes in parameter values.

Strategies to reduce the environmental impact of an aluminium pressure die casting plant: A scenario analysis

This study explores a model (MIKADO) to analyse scenarios for the reduction of the environmental impact of an aluminium die casting plant. Our model calculates the potential to reduce emissions, and the costs associated with implementation of reduction options. In an earlier paper [Neto, B., Kroeze, C., Hordijk, L., Costa, C., 2008. Modelling the environmental impact of an aluminium pressure die casting company and options for control. Environmental Modelling & Software 23 (2) 147-168] we included the model description and explored the model by applying it to a plant in which no reduction options are assumed to be implemented (so-called zero case, reflecting the current practice in the plant). Here, we perform a systematic analysis of reduction options. We analysed seven types of reduction strategies, assuming the simultaneous implementation of different reduction options. These strategies are analysed with respect to their potential to reduce emissions, environmental impact and costs associated with the implementation of options. These strategies were found to differ largely in their potential to reduce the environmental impact of the plant (10-87%), as well as in the costs associated with the implementation of options (-268 to +277keuro/year). We were able to define 11 strategies, reducing the overall environmental impact by more than 50%. Of these, two have net negative costs, indicating that the company may in fact earn money through their implementation.

Life cycle assessment of aquafeed ingredients

PurposeThis study performs an exploratory comparative evaluation of various animal and vegetable protein and lipid sources, used as feed in the aquaculture industry. The ingredients studied include fishmeal (FM) and fish oil (FO) from fisheries by-products, meal and fat by-products from poultry slaughter, FM and FO from Peruvian anchovy capture, and soybean meal and oil. The boundaries studied include the production or capture, the ingredient processing unit and the transport to the unit that processes the ingredients into aquafeeds in Portugal.MethodsThe LCA impact assessment method is the CML-IA baseline V3.04/EU25 and the results were obtained for the characterisation step. Some of the inventory data were collected from a Portuguese company (Savinor) that processes both by-products from local fisheries and by-products from poultry production. Savinor provided data specifically associated with the ingredients’ production. Obtained data were complemented with literature data from: fish capture and poultry production. Inventory data for the production of ingredients from Peruvian anchovy and soybeans were retrieved from literature. It was assumed that the transport of the ingredients produced from Peruvian anchovy, between Lima and Rotterdam, is made in a transoceanic vessel, and it is considered a transport by truck between Rotterdam and Ovar, for soybean ingredients and FM/FO produced from Peruvian anchovy.Results and discussionThis paper shows that poultry meal and poultry fat from poultry slaughter by-products have the larger contribution to all environmental impact categories evaluated, being the production of poultry the life cycle stage that contributes most to the overall categories. On the other hand, FM and FO from Peruvian anchovy were the ingredients with a lower contribution to all impact categories, except for abiotic depletion category, for FM from Peruvian anchovy, and abiotic depletion, abiotic depletion (fossil fuels) and ozone layer depletion for FO from Peruvian anchovy. For these categories, soybean meal and oil had lower impacts, respectively. The ingredients were compared by classes (protein and lipid sources).ConclusionsA general conclusion is that soybean meal and oil and FM/FO from Peruvian anchovy appear to be very interesting options for aquafeeds from an LCA perspective. However, some limitations identified for this study, as, for instance, that it does not account for the environmental benefits associated with the use of the mentioned by-products, that would otherwise be considered wastes (i.e. by-products from the fish canning sector and poultry slaughter) shall be evaluated in future studies.

Life Cycle Assessment of a shale gas exploration and exploitation project in the province of Burgos, Spain

Natural gas (NG) from shale formations (or shale gas) is an unconventional energy resource whose potential environmental impacts are still not adequately assessed. Hence, this study performs a Life Cycle Assessment (LCA) of shale gas considering a gas well under appraisal in Burgos, Spain. An attributional model was developed, considering the NG pre-production and production phases in the system boundaries, considering 1 MJ of processed NG as a functional unit. Results were obtained through the CML-IA baseline method (developed by the Center of Environmental Science of Leiden University) and showed that well design, drilling and casing, hydraulic fracturing, NG production, gathering, and processing are critical processes. To better address the environmental impacts, a comparison with similar studies was carried out, as well as a sensitivity and an uncertainty analysis using Monte Carlo simulation (MCS). The model was found to be particularly sensitive to water usage in hydraulic fracturing and to the number of workovers with hydraulic fracturing. Limited data availability for shale gas exploration still poses a challenge for an accurate LCA. Even though shale gas remains controversial, it still can be considered as a strategic energy resource, requiring a precautionary approach when considering its exploitation and exploration.

The use of green criteria in the public procurement of food products and catering services: a review of EU schemes

Green Public Procurement (GPP) is currently being used to influence the market to shift to a supply of goods and services to the public sector that have a reduced environmental impact. The food service sector plays a major role in the purchases made by the public sector and due to that relevance deserves attention. The GPP schemes reviewed were those that provide details of the specific environmental criteria used (or recommended) for public tendering of food products and catering services provision. The set of GPP schemes apply to distinct geographical zones within the EU, including national level (e.g. Italy), regional level (e.g. Barcelona) and also local level, as in the case of cities (e.g. Copenhagen) or schools (e.g. a school in Pisa, Italy). The criteria set covers services provision to schools, health and social care, higher education, government office canteens, sports and leisure arenas, prisons and defence services (e.g. army). European and worldwide GPP criteria were not covered by the review made. This exploratory study comprehends a total of 23 GPP schemes. This sample includes eight national schemes, three regional schemes and ten local schemes. The review focused on the scope, for the sector of applicability (e.g. education, healthcare) of the GPP set of criteria and for the type of food products covered. Moreover, this paper analyses the type of GPP criteria in use and how the environmental criteria cover the distinct life cycle stages of the whole food supply chain. Findings from the analysis show that for the majority of schemes the scope of criteria is simultaneously the provision of food products and catering services. Moreover, cities, municipalities and counties are the main public authorities reporting procurement activities for the education sector while national GPP activities are applicable for multiple sectors of activity. The main food products covered by the criteria are fruits and vegetables, dairy products, fish and seafood and meat. Finally, the findings show that the set of criteria from the schemes cover widely the life cycle stages of the food supply chain. The results allowed for a first identification of current practices in the use of GPP criteria within public purchasing of food products and catering services in Europe by national, regional or local governments.