The development of a resource-efficient photovoltaic system

This paper presents the measures taken in the demonstration of the photovoltaic case study developed within the European project ‘Towards zero waste in industrial networks’ (Zerowin), integrating the D4R (Design for recycling, repair, refurbishment and reuse) criteria at both system and industrial network level. The demonstration is divided into three phases. The first phase concerns the development of a D4R photovoltaic concept, the second phase focused on the development of a specific component of photovoltaic systems and the third phase was the demonstration of the D4R design in two complete photovoltaic systems (grid-connected and stand-alone). This paper includes a description of the installed photovoltaic systems, including a brief summary at component level of the lithium ion battery system and the D4R power conditioning system developed for the pilot installations. Additionally, industrial symbioses within the network associated with the photovoltaic systems and the production model for the network are described

Implications of Uncertainty and Variability in the Life

In a case study of pig production systems we propose a simple quantification of the uncertainty of LCA results (intra-system variability) and we explored inter-system variability in order to produce more robust LCA outcomes. Our quantification of the uncertainty took into account the variability of technical performance (crop yield, feed efficiency) and of emission factors (for NH 3 , N 2 O and NO 3 ) and the influence of the functional unit (FU) (kg of pig versus hectare used). For farming systems, the inter-system variability was investigated through differentiating by the production mode (conventional, quality label, organic (AB)), and farmer practices (Good Agricultural Practice (GAP) versus Current practice (CP)) while for natural systems, variability due to physical and climatic characteristics of catchments expected to modify nitrate fate was explored. For the eutrophication impact category, the variability of field emissions contributed more to uncertainty than the variability of building emissions, crop yield and feed efficiency. The influence of the FU on eutrophication results was very important when comparing systems with different degrees of intensification such as GAP and AB. Concerning inter-system variability, differences in farmer practices had a larger effect on eutrophication than differences between production modes. Finally, the physical characteristics of the catchment and the climate strongly affected the eutrophication result

Redox-dependent phosphorus burial in modern and ancient marine sediments. Geologica Ultraiectina (334)

Phosphorus (P) is an essential nutrient in Earth’s biosphere that helps regulate marine primary productivity. Burial in sediments is the only pathway for long-term removal of P from the marine reservoir, the efficiency of which depends strongly on the redox state of the bottom waters; oxygen-depleted conditions at the sediment-water interface enhance the recycling of P from the sediment back to the water column. In this thesis, the diagenesis and burial of P in relation to temporally and spatially variable redox conditions are investigated in modern and ancient sediments. The impact of sample treatment and long-term diagenesis on sedimentary P records is of special interest. It is shown that exposure of reducing, carbonate-poor sediments to oxygen can strongly alter the sedimentary P speciation through the effects of pyrite oxidation, rendering the artifact P speciation of little use to reconstruct redox conditions during sediment deposition. In addition, long-term diagenesis may impact P speciation in ancient, 94 Myrs-old sediments. Apart from these limitations, Cretaceous sedimentary records show a strong coupling between the burial efficiency of P and deposition of organic-rich sediments during oceanic anoxic event (OAE) 2, ~ 94 Myrs ago, suggesting that enhanced P availability may have helped to sustain high productivity. In younger, Quaternary sediments in long cores from the Mediterranean Sea, the in situ P speciation and organic carbon to phosphorus ratios have been preserved and can be used to reconstruct paleoceanographic conditions during formation of the investigated sediments. Detailed investigation of both the Cretaceous and Quaternary sediments suggest that fish debris can constitute an important sedimentary P sink during periods of high primary productivity and bottom water oxygen depletion in Earth’s past. Due to rapid deposition and burial, the abundance of fish debris in marine sediments can provide valuable information on surface water productivity. The techniques applied to investigate the chemical forms of P in sediments become ever more advanced. This development is incorporated in this thesis in the form of a study employing both classic sequential P extractions and advanced X-ray P spectroscopy to quantify P speciation in marine sediments. The results underline the reliability of sequential extraction as a fast, economic tool to quantify sedimentary P speciation and highlight the added advantage of X-ray spectroscopy, which enables not only bulk P speciation but also provides information on the mineralogy and crystallinity of the sedimentary P phases. Finally, P cycling in modern sediments from a depth transect across the oxygen minimum zone (OMZ) in the northern Arabian Sea was investigated. The results show that formation of authigenic calcium-phosphate minerals (Ca-P) is largely restricted to sediments in the OMZ, where the increased input of labile P phases compensates for enhanced recycling of P under more oxygen-depleted conditions. Iron redox cycling is important to sedimentary P retention and authigenic Ca-P formation. Furthermore, dust deposition may be an important source of calcium phosphate minerals in the investigated sediments. Accounting for dust-derived, detrital P results in the downward correction of the reactive, non-detrital, P burial efficiency in Arabian Sea sediment

Lifetime robustness of a RC bridge pier under corrosion considering bridge importance

A probabilistic approach to lifetime robustness of deteriorating bridges is presented. The role of the environmental damage on structural robustness is investigated by comparing the performance indicators in the original state, in which the structure is intact, and in a perturbed state, in which a damage scenario is applied. The robustness criterion is formulated by taking the importance of the structure into account. The proposed approach is applied to a reinforced concrete bridge pier with box cross-section exposed to corrosion. The results demonstrate the effectiveness of the proposed approach and show the role of the importance of the structure in the assessment of lifetime robustness