Environmental impact assessment of a WtE plant after structural upgrade measures

The study focuses on analysing the evolution of environmental impacts caused by a medium–large Italian WtE plant before and after revamping and maintenance operations, with the aim of providing an evaluation of how much these structural upgrade measures may affect the total environmental performance.LCA methodology was applied for the modelling and comparison of six WtE scenarios, each describing the main structural upgrades carried out in the plant over the years 1996–2011. The comparison was conducted by adopting 1 ton of MSW as the functional unit, and the net contribution from energy recovery to power generation was distinguished by defining consistent national grid electricity mixes for every year considered. The Ecoindicator99 2.09 impact assessment method was used to evaluate the contribution to midpoint and endpoint categories (e.g. carcinogens, respiratory inorganics and organics, climate change, damage to human health). Lastly, the “Pedigree quality matrix” was applied to verify the reliability and robustness of the model created.As expected, the results showed better environmental scores after both the implementation of new procedures and the integration of operations. However, while a net reduction of air emissions seems to be achievable through dedicated flue gas treatment technologies, outcomes underscored potentials for improving the management of bottom ash through the adoption of alternative options aimed to use that solid residue mainly as filler, and to decrease risks from its current disposal in landfill. If the same effort that is put into flue gas treatment were devoted to energy recovery, the targets for the WtE plant could be easily met, achieving a higher sustainability. This aspect is even more complex: national policies for implementing greener and renewable energy sources would result in a lower impact of the national energy mix and, hence, in a lower net avoided burden from energy recovery.The study confirmed the expected improvements, indicating quantitatively the lower environmental impact resulting from structural upgrade operations in a WtE plant. Furthermore, the work highlights the importance of considering the evolution of the national energy mix in LCA studies, especially during the present years of transition from fossil fuels to renewable sources.     

Constellations and careers: toward understanding the effects of multiple developmental relationships

This paper examines the effects of individuals' primary and multiple developmental relationships in a longitudinal study of the careers of lawyers. By juxtaposing the effects of the primary developmental relationship with those of individuals' sets or ‘constellations’ of developmental relationships, the present study lends insight into if and when these two perspectives on mentoring yield different results regarding the effects of mentoring on protégé career outcomes. The findings from the present study show that while the quality of one's primary developer affects short‐term career outcomes such as work satisfaction and intentions to remain with one's firm, it is the composition and quality of an individual's entire constellation of developmental relationships that account for long‐run protégé career outcomes such as organizational retention and promotion. Further, results from the present study provide evidence that the constellation perspective explains greater variance with respect to protégé career outcomes than does the primary or more traditional perspective on mentoring. Implications for research on mentoring, developmental relationships, and careers are discussed. Copyright © 2001 John Wiley & Sons, Ltd.     

Safety management systems: Performance differences between adopters and non-adopters

The aim of this paper is to assess, through an empirical investigation, whether the performance of safety management systems (SMSs) adopting and non-adopting companies statistically differ. To achieve such aim, empirical data were collected on a sample of 116 companies, encompassing both SMSs adopters and non-adopters. Hypotheses testing was performed to assess whether SMSs adopters experience significantly higher performance against (i) definition of safety and security goals and their communication to employees; (ii) risk data updating and risk analysis; (iii) identification of risks and definition of corrective actions; (iv) employees training. Results show that companies adopting SMSs exhibit higher performance against all the topics identified. These outcomes could be the starting point for providing empirical evidence of benefits achievable thanks to SMSs implementation.     

The Value-Action Gap in Waste Recycling: The Case of Undergraduates in Hong Kong

The discrepancy between verbal and actual commitment in waste recycling and environmental behavior is thought to have attenuated the effectiveness of many environmental policy and measures. Studies purport to show the existence of such a value-action gap in environmental issues has been largely based on matching the verbal commitment to environmental value through self-reported environmental behavioral data. Therefore, there is a lack of direct evidence to prove that such a discrepancy exists. This study demonstrates a methodology (contrasting on-site observation with self-reported results) to measure the gap between verbal commitment and actual recycling behavior and provides an explanation on the recycling behavior of students at Hong Kong Baptist University in the hope that the lessons learnt can be generalized to a wider context. Our findings indicate that a gap between verbal recycling commitment and corresponding action does exist in waste recycling on this university campus. By using multiple linear regression analysis, we found that the self-reported recycling behavior of undergraduates cannot be meaningfully explained by most variables previously suggested in the general value-action model.     

Sediment phosphorus extractants for phosphorus-31 nuclear magnetic resonance analysis: a quantitative evaluation

The influence of pre-extractant, extractant, and post-extractant on total extracted amounts of P and organic P compound groups measured with 31P nuclear magnetic resonance (31P-NMR) in lacustrine sediment was examined. The main extractants investigated were sodium hydroxide (NaOH) and sodium hydroxide ethylenediaminetetraacetic acid (NaOH-EDTA) with bicarbonate buffered dithionite (BD) or EDTA as pre-extractants. Post extractions were conducted using either NaOH or NaOH-EDTA, depending on the main extractant. Results showed that the most efficient combination of extractants for total P yield was NaOH with EDTA as pre-extractant, yielding almost 50% more than the second best procedure. The P compound groups varying the most between the different extraction procedures were polyphosphates and pyrophosphates. NaOH with BD as pre-extractant was the most efficient combination for these compound groups.