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Purpose Cradle-to-gate life cycle inventories (LCIs) for the production of a series of common surfactants used in European detergents and personal care products have been voluntarily compiled by 14 major companies collaborating within ERASM (www.erasm.org). The study builds on a similar project executed by CEFIC-Franklin (1994) and summarised by Stalmans et al. (Tenside Surf Det 32:84-109, 1995). The data are targeted as an industry-agreed and representative market average for surfactants in Europe for the reference year 2011. The purpose of this paper is to describe how these dataset were generated, to provide some summary results and interpretation, and to indicate where the full datasets and additional technical documentation can be found. Methods The methodology followed was an attributional life cycle assessment (LCA) approach, compliant with LCA standards ISO 14040 (2006), ISO 14044 (2006), and ILCD entry level (2010). For each major unit process in the production of surfactants and precursors, a minimum of three companies (a 'trio') was identified. When no industry-specific data were available, either literature or recent and reliable process data were used. For worldwide traded precursor materials like palm oil, palm kernel oil, and coconut oil, an extensive literaturebased LCI study was performed. Two independent external reviewers supported the project from the beginning through completion. In addition, the oil palm and coconut-and tallowbased renewable precursors were reviewed by a third independent expert.Results and discussion In the study, a good level of representativeness was achieved with 70 primary data collections in 12 companies. To illustrate the outcome of the work, two indicators/impacts were calculated and reported, i.e. primary energy demand (PED) and global warming potential (GWP). The LCIs allow the calculation of additional impact categories, but these were not analysed within the scope of this project.The PED for most of the surfactants and their precursors is in the range of 52 to 77 GJ/tonne. Exceptions are the production of cocamide diethanolamine (CDEA) and C16-C18 triethanolamine esterquat (TEA-quat) with a PED of around 40 GJ/tonne, and 3-dimethylaminopropylamine (DMAPA) around 108 GJ/tonne. Petrochemical precursors show an intensive but established and optimised supply chain. Where comparison is possible, their PED does not differ much from the earlier CEFIC-Franklin (1994) data. There are indications that PED for surfactant production has decreased slightly over the last 20 years due to energy efficiency measures.The GWP for the reportable precursors ranges from − 1989 kg CO 2 e/tonne for Coconut Oil Methyl Ester to 4894 kg CO 2 e/tonne for DMAPA. For the final surfactants, the range is from − 887 kg CO 2 e/tonne for CDEA to 2674 kg CO 2 e/tonne for C12-C15 AE3. There is a significant difference between the cradle-to-gate GWP of the renewable precursors palm oil/palm kernel oil (PO/PKO) and coconut oil (CNO). The CNO products have a calculated net negative cradle-to-g...

Abstract.The model presented here is based on fuzzy arithmetic techniques and the MIVES method, which is based, in turn, on requirement trees, value analysis and the Analytic Hierarchy Process. Even though it encompasses the approach for assessing sustainability adopted by the Spanish Structural Concrete Code (EHE), the model can also be applied to concrete structures designed according to other structural codes. The EHE model serves to estimate the Structure's Contribution to Sustainability Index (ICES) and constitutes the first sustainability model included in a structural code. The ICES crisp model is inadequate in terms of managing the structural sustainability objective of medium and high uncertainty projects. In such cases, a method not only has to assess the potential sustainability index at the end of the project, but also the degree of uncertainty affecting compliance with the sustainability objective laid down by the client or promoter. The paper compares this model with a Monte Carlo simulation method conceived for the same purpose. The fuzzy method could be a better solution in specific cases of limited time or budget for creating the model.

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This paper reports on an investigation into the effects of the shape of concrete paving blocks used in permeable pavements. It describes a series of hydraulic performance tests on blocks with different drainage slot geometries, in order to determine their influence on infiltration capacity. Paving samples were tested in a purpose-designed laboratory rig consisting of a variable-gradient testing frame, rain simulator and water-collecting chambers. The apparatus allowed for slope variations and two inputs of water: input runoff and direct rainfall over the surface. Four differently shaped slotted concrete blocks were tested under three different clogging states and four gradients. The results obtained lead to initial conclusions about the influence of block geometry on the hydraulic performance of paving which have implications for pavement design.