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BACKGROUND Spent sulfite liquor is a by‐product obtained in the process of manufacturing dissolving pulp by the acid sulfite method. A full physico‐chemical characterization of this waste has been developed in order to determine if it is susceptible to valorization by means of biorefinery processes. RESULTS The main components present in this spent liquor are sugars from hemicelluloses (25.9%), mainly xylose (18.2%) because hardwood is used as a raw material, and lignosulfonates (50.6%). Taking into account the results obtained, a literature search has been done in order to establish the biorefinery options for this lignocellulosic waste, giving lignosulfonates, xylitol, ethanol, polyhydroxybutyrate or polybutylene‐succinate, hydrogen and furfural as the best options. However, other compounds present in the liquor such as furans, acids and inorganic pollutants can complicate the valorization options. CONCLUSIONS Spent sulfite liquor can be a good feedstock for biomass based processes. This paper will be useful for future work regarding the potential biorefinery opportunities of the sulfite mill. © 2014 Society of Chemical Industry

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Construction and demolition waste (C&DW) constitutes a priority waste stream in the European waste strategy due to its large volume and its high recycling and reuse potential. Directive 2008/98/EC on waste, stresses the need of quantify the waste stream and to improve the material recovery efficiency of C&DW in the European Union. Designing a suitable network of facilities involves an adequate knowledge of the inputs to material recovery facilities. In this work, a two-step methodology for the quantification and waste management analysis of C&DW has been developed and applied to the case study in Cantabria, a northern Spanish region. In the first step, the quantification of C&DW was calculated by means of an equation which combines municipal licenses and ratios of waste per unit area of construction, demolition and renovation. The selected ratios for the study case in Cantabria belong to four northern Spanish regions, and they were developed by two associations of architects, one technological institute and by the regional legislation recently developed in the region. In the second step, the waste management assessment for C&DW was carry out throw the development of a multicriteria-based methodology for decision-making in order to select the most suitable management alternative. The application of the methodology to the case study in Cantabria has been performed using four multicriteria analysis methods: Evamix (EV), Weighted Summation (WS), Electre II (E2) and Regime (REG). Analyses of the sensitivity of the results have been also carried out in order to investigate the robustness of the solutions obtained in the decision making process.

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The treatment of fully and partly weathered olive mill wastewaters by means of ozonation was investigated, with emphasis on the effect of treatment conditions (organic loading, treatment time, ozone concentration) on the extent of chemical oxygen demand (COD) and total phenol degradation, colour removal as well as ecotoxicity to the marine bacterium Vibrio fischeri. In general, ozonation was capable of substantially reducing the concentration of phenols as well as decolourising the effluent after relatively short treatment times, with the extent of phenol and colour removal exceeding 80% in most cases. The fast and selective degradation of phenols was ascribed to the direct electrophilic attack by molecular ozone (ozonolysis). Conversely, complete mineralisation proved difficult; at the conditions employed in this study, COD removal varied from as little as 10% to about 60%. Both effluents were strongly ecotoxic owing to the presence of phenols and other organics in substantial concentrations; toxicity decreased partly following considerable degradation of the organic matter.