Search

Industrial activities generate different types of waste, with varying chemical properties. An investigation of the detailed chemical and mineralogical characteristics of these materials may serve as a first step for selecting an appropriate treatment or safe disposal method. This study focuses on arsenic (As) and heavy metals (i.e., Cd, Co, Cu, Cr, Mo, Ni, Pb, and Zn) in three sludge samples derived from industrial wastewater treatment plants in Southern Vietnam. The emphasis is on determining the influence of changing environmental conditions on element mobilization based on a multidisciplinary approach using sample micro analysis (Field Emission Gun Electron Probe Micro Analysis (FEG-EPMA)) in combination with different types of leaching/extraction tests. ispartof: pages:107-108 ispartof: Interfaces Against Pollution -Environmental Challenges & Opportunities- Book of abstracts pages:107-108 ispartof: Interfaces Against Pollution (IAP 2016) location:Lleida (Spain) date:4 Sep - 7 Sep 2016 status: published

On December 2nd, 2015 the European Commission published a new Circular Economy Package to stimulate Europe's transition towards a circular economy, aimed at boosting global competitiveness, fostering sustainable economic growth, decreasing carbon emissions, and generating 580,000 new jobs. The engineers educated today will be key role players in this ambitious plan. An important focus in circular economy education lies in aspects of resource efficiency, using less raw materials and energy, and innovative processes and products. Whereas this is a certainly challenging to stimulate the creativity, innovation, and entrepreneurial spirit of engineering students, social aspects of the circular economy perspective cannot be neglected and definitely deserve more attention. Both producers and consumers play a role in the transition towards a circular economy. Although general public awareness about the circular economy will likely increase in the coming years, usability, acceptability, and user incentives are essential to design successful circular systems. It is here that engineers can play an important role, in engineering and designing their products so that they are accepted by the consumers. Besides the environmental impact of materials and products over their entire life cycle, social impacts (such as the social well-being of different actors and stakeholders in the value chain of a product), are receiving more and more attention. Social wellbeing is not only enhanced through resource efficiency improvements, but also by issues of societal concern, for example: job creation, labor conditions, transparent communication about a product (over its entire life cycle), etc. In the present paper, we discuss some examples of how the societal impact of the circular economy concept can be addressed in courses and curricula in engineering education and beyond. Attention is paid to the role of life cycling thinking in adopting the circular economy concept, thus addressing environmental, economic, and social aspects. Examples also show the importance of taking into account consumer behaviour to analyse problems associated with human use of goods and services, within a circular economy framework Finally, we illustrate some interesting examples on truly interdisciplinary (student) projects. No ISSN ispartof: pages:212-218 ispartof: Proceedings of the 8th International conference on Engineering Education for Sustainable Development pages:212-218 ispartof: International conference on Engineering Education for Sustainable Development location:Bruges date:4 Sep - 7 Sep 2016 status: published

Although Ba is a non-regulated element in soil in most European countries, some countries, such as Canada, are adopting quality guidelines because this element can be toxic at high concentrations. The aim of the present study was to assess Ba concentrations and availability in Flemish floodplain soils. For a rapid screening of availability, single extractions recommended by BCR (with CaCl2 0.01 mol/L, acetic acid 0.43 mol/L and ammonium-EDTA 0.05 mol/L) were performed. Additionally, a 0.1 mol/L CaCl2 extraction was used, to determine ‘soluble barium' as stipulated in the Canadian guidelines established by Alberta Environment. A comparison was also made to concentrations reported in literature, and with Ba concentrations in subsoils, topsoils and floodplain soils included in the FOREGS database. Single extractions indicate that only a very small proportion of Ba is readily available for uptake by living organisms or for leaching. Elevated total Ba concentrations are not indicative of a higher risk of mobilization, even when other parameters such as matrix composition and pH are taken into account. The use of single extractions should be considered when environmental quality guidelines are set up for Ba, as they can be useful for a fast screening of potential Ba contamination with an unacceptable risk for the environment. Moreover, regression equations with major elements as independent variables allow to predict Ba concentrations in soils, and also enable to detect potential anomalies. No ISBN/ISSN ispartof: pages:188-188 ispartof: Proceedings of the 32nd conference on Environmental Geochemistry and Health pages:188-188 ispartof: International conference on Environmental Geochemistry and Health location:Brussels (Belgium) date:4 Jul - 8 Jul 2016 status: published

Despite the fact that red mud is often contaminated with heavy metals and metalloids, its use in environmental remediation has widely been investigated and applied from laboratory to field scale. Red mud is efficient for the removal of various aquatic pollutants, especially arsenic and phosphate, from waste waters, but the practical utility of these adsorbents on a commercial scale still needs more investigation. Another application of red mud that receives less attention, is its use in soil remediation. In the present paper, the application potential of red mud as a soil amendment for contaminant immobilisation was critically reviewed. no issn ispartof: pages:81-87 ispartof: Proceedings of the Bauxite Residue Valorisation and Best Practices conference vol:1 issue:1 pages:81-87 ispartof: Bauxite Residue Valorisation and Best Practices location:Leuven date:5 Oct - 7 Oct 2015 status: published

After being used as an abrasive agent, copper slag is considered a solid waste in Vietnam because appropriate waste treatment techniques and effective management options are not available. This classification as solid waste is mainly due to the fact that the blasted copper slag (BCS) contain impurities of potentially toxic elements (PTEs), such as As, Cd, Co, Cr, Cu, Mo, Ni, Pb, and Zn that can be released into environment. The present study was conducted with the aim to characterize the solid phase composition of blasted copper slag (BCS) and to investigate the leaching of PTEs from BCS under influence of pH. A wide pH range (1-10) was investigated in order to assess the environmental implications of different management scenarios. Besides amorphous phases, fayalite, magnetite, maghemite, quartz and elemental copper were the main minerals identified by X-ray diffraction (XRD). Field Emission Gun Electron Probe Micro Analysis (FEG-EPMA) results indicated that BCS mainly consisted of Fe, O and Si with minor amounts of S whereas the copper bearing phase was composed of Cu, Pb, and S with small amounts of Si. This indicates that copper in BCS was present not only in metallic phases but also in association with S in the form of sulphides (sulphides of Cu, Cu-Pb, Cu-Pb-Zn). Mapping of selected areas in thin sections with wavelength dispersive spectrometry also confirmed the presence of these sulphide phases which were not detected by XRD. Among the examined PTEs, Cr was found in Fe-O rich phases, while Mo was observed in a glass inclusion. These This might explain the low leachability of these elements in neutral pH conditions. Leaching tests indicated that most of the PTEs showed a low environmental concern in the neutral-alkaline pH range due to the low concentrations in the leachate compared to EU leaching limit value for non-hazardous waste, except As which exceeded this threshold at pH 10. Moreover, in the case of acidification (e.g. as a results of co-disposal with acid waste or as a result of acid rain), special attention should be paid to Cu and Zn which exhibit an important release at pH 3-5. On the other hand, recovery of Cu by acid treatment of the slag could be considered since an extraction with HNO3 1 M during 24 h showed that 39 % of the total Cu content (or 3369 mg/kg) was released from the slag. The feasibility of Cu recovery from the slag should be further investigated. no issn ispartof: pages:155-159 ispartof: Proceedings of the fourth International Slag Valorization Symposium vol:4 pages:155-159 ispartof: Slag Valorization Symposium location:Leuven date:15 Apr - 17 Apr 2015 status: published

In Flanders (Belgium), approximately 12 000 kton of dredged sediments has to find a destination every year. A possible application is the use of dredged sediments as a raw material in brick production. Despite the fact that several examples in neighboring countries show that this is application is feasible, some socio-economic and technical limitations interfere with the use of dredged materials in brick production in Flanders. In the present study, the limitations and barriers, from the consumers’ point of view were analyzed, based on a survey held in Flanders. The survey dealt with the risk perception of citizens with respect to environmental problems in general and (contaminated) sediments in particular and with their the willingness to pay for bricks produced from traditional raw materials (clay) and from dredged sediments. The Decree on Materials management considers dredged sediments as a secondary resource, that can be used as a resource for building materials as long as they comply with certain criteria. Technical problems, such as the dewatering of sediments, have been solved during the last few years, but the real valorization of dredged sediments in high-grade applications is still very limited. The survey indicated that consumers in Flanders are rather suspicious with respect to bricks produced from dredged sediments and their risk perception is mainly determined by the possibility of a bad bargain, the social acceptance of the product, the connotation with contaminated river sediments and personal characteristics such as flexibility and independence. The willingness to pay for bricks made from dredged sediments is mainly influenced by the age of the respondents, as well environmental awareness, and the respondents’ belief in their ability to influence environmental problems. More than 50% of the respondents indicated that they had insufficient knowledge on this topic, despite the fact that 60% of the respondents had a higher education degree. Sensitization and information of customers is of primary importance to make dredged-sediment-derived bricks a successful product ispartof: Abstracts of the 4th International Symposium on Sediment Management ispartof: International Symposium on Sediment Management (I2SM) location:Ferrara (Italy) date:17 Sep - 19 Sep 2014 status: published