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Fly ash (FA) from biomass combustion and biological sludge (S), both wastes from the pulp and paper industry, were granulated in different proportions (90% FA + 10% S, and 70% FA + 30% S w/w, dry weight basis, dw) and used to recover the functionality of soils affected by mining activities (Aljustrel, Iberian Pyrite Belt), with and without the application of municipal solid waste compost (MSWC). Application doses of both mixtures were 2.5, 5.0 and 10% (w/w, dw). These materials corrected soil acidity to circumneutral values and increased extractable P and K concentrations. A significant increase in soil organic matter (from 0.6 to 0.8–1.5% w/w, dw) and N content (from 0.04 to 0.09–0.12% w/w, dw) was also observed, but only when MSWC was applied. The soil was already heavily contaminated with Cu, Pb and Zn and the application of amendments did not increase their pseudo-total concentrations. The CaCl2 extractable fractions of both Cu and Zn decreased to very low values. The improvement in soil quality, compared to fertilizer only treatment, was further evidenced by the increase in some soil enzymatic activities (dehydrogenase, β-glucosidase and cellulase), with a better response for the granules with the higher proportion of biological sludge, as well as by the decrease in the soil-water extract toxicity towards different organisms (Daphnia magna, Thamnocephalus platyurus, and Pseudokirchneriella subcapitata). Agrostis tenuis germinated and grew during the first month only in the amended pots, but, after that, a considerable phytotoxic effect was evident. This was mainly attributed to salt stress or to some specific ionic toxicity. In conclusion, to establish a long-term plant cover in mining soils amended with biomass ash-based materials, the selection of plants with higher resistance to salinity and/or the stabilization of the amendments, to reduce their soluble salt content, is recommended.

The wide occurrence of pharmaceuticals in aquatic environments urges the development of cost-effective solutions for their removal from water. In a circular economy context, primary paper mill sludge (PS) was used to produce activated carbon (AC) aiming the adsorptive removal of these contaminants. The use of low-cost precursors for the preparation of ACs capable of competing with commercial ACs continues to be a challenge. A full factorial design of four factors (pyrolysis temperature, residence time, precursor/activating agent ratio, and type of activating agent) at two levels was applied to the production of AC using PS as precursor. The responses analysed were the yield of production, percentage of adsorption for three pharmaceuticals (sulfamethoxazole, carbamazepine, and paroxetine), specific surface area (S ), and total organic carbon (TOC). Statistical analysis was performed to evaluate influencing factors in the responses and to determine the most favourable production conditions. Four ACs presented very good responses, namely on the adsorption of the pharmaceuticals under study (average adsorption percentage around 78%, which is above that of commercial AC), and S between 1389 and 1627 m g . A desirability analysis pointed out 800 °C for 60 min and a precursor/KOH ratio of 1:1 (w/w) as the optimal production conditions., This work was funded by FEDER through COMPETE 2020 and by national funds through FCT by the research project PTDC/AAG-TEC/ 1762/2014. Thanks are also due for the financial support to CESAM (UID/AMB/50017-POCI-01-0145-FEDER-007638), to FCT/MCTES through national funds (PIDDAC), and the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020. The work was also developed within the scope of the project CICECO - Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (UID/ CTM/50011/2013), financed by national funds through the FCT/MEC. Vânia Calisto also thanks FCT for her postdoctoral grant (SFRH/BPD/ 78645/2011). Marta Otero and Sérgio Santos thank support by the FCT Investigator Program (IF/00314/2015 and IF/00973/2014, respectively).

Advanced Oxidation Processes (AOPs) are called to fill the gap between the treatability attained by conventional physico-chemical and biological treatments and the day-to-day more exigent limits fixed by environmental regulations. They are particularly important for the removal of anthropogenic pollutants and for this reason, they have been widely investigated in the last decades and even applied in the treatment of many industrial wastewater flows. However, despite the great development reached, AOPs cannot be considered mature yet and there are many new fields worthy of research. Some of them are going to be briefly introduced in this paper, including hybrid processes, heterogeneous semiconductor photocatalysis, sulphate-radical oxidation and electrochemical advanced oxidation for water/wastewater treatment. Moreover, the use of photoelectrochemical processes for energy production is discussed. The work ends with some perspectives that can be of interest for the ongoing and future research., Los Procesos de Oxidación Avanzada (POAs) están llamados a llenar el vacío entre la tratabilidad alcanzada por los tratamientos físico-químicos y biológicos convencionales y los límites cada día más exigentes fijados por la normativa medioambiental. Son particularmente importantes para la remoción de contaminantes antropogénicos y por esta razón han sido ampliamente investigados en las últimas décadas e incluso aplicados en el tratamiento de muchos flujos de aguas residuales industriales. Sin embargo, a pesar del gran desarrollo alcanzado, los POA aún no pueden considerarse maduros y existen muchos campos nuevos dignos de investigación. Algunos de ellos se presentarán brevemente en este artículo, incluidos los procesos híbridos, la fotocatálisis de semiconductores heterogéneos, la oxidación por radicales de sulfato y la oxidación electroquímica avanzada para el tratamiento de agua/aguas residuales. Además, se discute el uso de procesos fotoelectroquímicos para la producción de energía. El trabajo finaliza con algunas perspectivas que pueden ser de interés para las investigaciones en curso y futuras.

Pulp and paper industry produces massive amounts of sludge from wastewater treatment, which constitute an enormous environmental challenge. A possible management option is the conversion of sludge into carbon-based adsorbents to be applied in water remediation. For such utilization it is important to investigate if sludge is a consistent raw material originating reproducible final materials (either over time or from different manufacturing processes), which is the main goal of this work. For that purpose, different primary (PS) and biological sludge (BS) batches from two factories with different operation modes were sampled and subjected to pyrolysis (P materials) and to pyrolysis followed by acid washing (PW materials). All the materials were characterized by proximate analysis, total organic carbon (TOC) and inorganic carbon (IC), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and N2 adsorption isotherms (specific surface area (SBET)and porosity determination). Sludge from the two factories proved to have distinct physicochemical properties, mainly in what concerns IC. After pyrolysis, the washing step was essential to reduce IC and to considerably increase SBET, yet with high impact in the final production yield. Among the materials here produced, PW materials from PS were those having the highest SBET values (387-488 m2 g-1). Overall, it was found that precursors from different factories might originate final materials with distinct characteristics, being essential to take into account this source of variability when considering paper mill sludge as a raw material. Nevertheless, for PS, low variability was found between batches, which points out to the reliability of such residues to be used as precursors of carbon adsorbents. L'Oreal Portugal published

Fibres fractionated from solid recovered fuel (SRF), a standardised market combustion fuel produced from sorted waste, were considered as a source of lignocellulosic fermentable sugars. The fibre yield from four samples of SRF was 25-45%, and the separated material consisted of 52-54% carbohydrates, mainly glucan, with a high content of ash (12-17%). The enzymatic digestibility of recovered fibres was studied at low and high solids loading and compared with model substrates containing only chemical and mechanical pulps. Above 80% hydrolysis yield was reached at 20% solids loading in 48. h, but variation was observed between different samples of recovered fibres. Surfactants were found to improve the hydrolysis yield of recovered fibres especially in tumbling-type of mixing at low solids loading, where hydrolysis was found to stagnate without surfactants. The results suggest that SRF is a potential source of easily digestible lignocellulosic carbohydrates for use in biorefineries.

Some Chilean copper slag dumps from the nineteenth century still remain, without a proposed use that encourages recycling and reduces environmental impact. In this paper, the copper slag abandoned in landfills is proposed as a new building material. The slags studied were taken from Playa Negra and Puquios dumps, both located in the region of Atacama in northern Chile. Pozzolanic activity in lime and Portland cement systems, as well as the alkali activation in pastes with copper slag cured at different temperatures, was studied. The reactivity of the slag was measured using thermogravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD), electrical conductivity and pH in aqueous suspension and Fourier Transform Infrared Spectroscopy (FTIR). Furthermore, copper slag-Portland cement mortars with the substitution of 25% (by weight) of cement by copper slag and alkali-activated slag mortars cured at 20 and 65 °C were made, to determine the compressive strength. The results indicate that the ancient copper slags studied have interesting binding properties for the construction sector.

International audience; Microbial bioanodes were formed in pulp and paper effluent on graphite plate electrodes under constant polarization at -0.3 V/SCE, without any addition of nutriment or substrate. The bioanodes were characterized in 3-electrode set-ups, in continuous mode, with hydraulic retention times from 6 to 48 h and inlet COD from 500 to 5200 mg/L. Current densities around 4 A/m2 were obtained and voltammetry curves indicated that 6 A/m2 could be reached at +0.1 V/SCE. A theoretical model was designed, which allowed the effects of HRT and COD to be distinguished in the complex experimental data obtained with concomitant variations of the two parameters. COD removal due to the electrochemical process was proportional to the hydraulic retention time and obeyed a Michaelis-Menten law with respect to the COD of the outlet flow, with a Michaelis constant KCOD of 400 mg/L. An inhibition effect occurred above inlet COD of around 3000 mg/L.

The use of waste wood as an energy carrier has increased during the last decade. However, elevated levels of alkali metals and chlorine in waste wood compared to virgin biomass can cause increased deposit formation and higher concentrations of organic pollutants. In this study, we investigated the effect of the ChlorOut technique on concentrations of organic pollutants. Ammonium sulfate was injected into the combustion system to inhibit formation of KCl (which causes deposits) and persistent organic pollutants, namely polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs). The results showed that concentrations of the toxic congeners of PCDD, PCDF and PCB decreased in the presence of ammonium sulfate.

[EN] The control of soluble metal species in the sub-product leachate generated in electricity production processes is of great concern from an environmental and health point of view. Unlike fly ash, the leaching behaviour of char materials has received little attention. Yet, these solids are captured together with fly ashes in the particle control devices of power plants and are emitted in the same way as by-products. The present study was carried out using two char samples: (i) a raw char and (ii) the same type of char employed in a previous study so that it could serve as a sorbent for mercury species in gas phase. The char samples were by-products (residues) that had been generated during the gasification of plastic and paper waste. The leachates were analyzed for the following elements: Al, Ca, Si, Mg, Ba, Cu, Ni, Pb, Zn, Mo and Hg. In addition, geochemical modelling of the leaching test results was employed to identify the underlying chemical processes that led to the release of toxic elements. The results showed that at alkaline pH values, sorption on the solid surfaces of the char was negligible due to the inorganic complexation of cations in the solution. When the char was used as mercury sorbent slight changes occurred on the reactive surface resulting in the modification of the binding of some elements. As the pH increased, complexation with dissolved organic matter played a more important role in the case of some elements such as Cu because of the greater concentration of dissolved organic matter in solution., The financial support for this work was provided by the project MERCURYCAP (RFCR-CT-2007-00007). The authors thank the Energy Research Centre of the Netherlands for supplying the chars employed in this study and the Spanish Research Council (CSIC) for awarding Ms. Aida Fuente-Cuesta a pre-doctoral fellowship and Mª Antonia Lopez-Anton with a JAE-Doc contract (European Social Fund).

The closure of water circuits within pulp and paper mills has resulted in a higher contamination load of the final mill effluent, which must consequently be further treated in many cases to meet the standards imposed by the legislation in force. Different treatment strategies based on advanced oxidation processes (ozonation and TiO2-photocatalysis), and their combination with biological treatment (MBR), are herein assessed for effluents of a recycled paper mill and a kraft pulp mill. Ozone treatment achieved the highest efficiency of all. The consumption of 2.4 g O3 L−1 resulted in about a 60% COD reduction treating the effluent from the kraft pulp mill at an initial pH = 7; although it only reached about a 35% COD removal for the effluent of the recycled paper mill. Otherwise, photocatalysis achieved about a 20–30% reduction of the COD for both type of effluents. In addition, the effluent from the recycled paper mill showed a higher biodegradability, so combinations of these AOPs with biological treatment were tested. As a result, photocatalysis did not report any significant COD reduction improvement whether being performed as pre- or post-treatment of the biological process; whereas the use of ozonation as post-biological treatment enhanced COD removal a further 10%, summing up a total 90% reduction of the COD for the combined treatment, as well as it also supposed an increase of the presence of volatile fatty acids, which might ultimately enable the resultant wastewater to be recirculated back to further biological treatment.

Cellulosic wastes, from sources such as low-quality cardboard and paper, are regarded as potential feedstocks for bioethanol production. One pathway from these cellulosic materials to ethanol is saccharification (hydrolysis) followed by fermentation. Saccharification is commonly performed using enzymes that are able to cleave the cellulosic structure to smaller units, preferably to glucose monomers. During the hydrolysis, mixing conditions have a considerable impact on the performance of the enzymes. Thus mixing conditions in the hydrolysis tank can also influence the downstream operations and, consequently, the overall economy of the bioethanol process. In this experimental study, four types of impeller, at different hydrolysis conditions were used. The effect of mixing on the glucose yield and on the filtration characteristics of the hydrolysate was evaluated. It was shown that not only the sugar yield depended on the mixing conditions: the effect on the solid–liquid separation step was even more significant. Post-print / Final draft

The potential of the lipoxygenase from Gaeumannomyces graminis to remove lipophilic extractives from eucalypt and flax pulps was investigated. Pulp treatments were performed with the lipoxygenase both in the presence and absence of linoleic acid, and were followed by a peroxide bleaching stage. The main lipophilic extractives from eucalypt pulp such as conjugated and free sterols decreased up to 40% and 7%, respectively, by the lipoxygenase treatment in the presence of linoleic acid. Different degradation patterns were observed among the lipophilic compounds present in flax pulp, although a high removal of all the extractives classes, including alkanes (21-55%), fatty alcohols (42-61%), and free (16-55%) and glycosylated (45-71%) sterols, was attained in all the lipoxygenase treatments. Reactions of the lipoxygenase with model lipid mixtures were carried out to better understand the degradation patterns observed in pulps. Finally, pulp delignification by the lipoxygenase treatments was also evaluated., This study has been supported by the Spanish projects BIO2007-28719-E and AGL2008-00709 and the EU project BIORE- NEW (NMP2-CT-2006-026456).

Instituto de Recursos Naturales y Agrobiología, CSIC, P.O. Box 1052, E-41080, Seville, Spain E-mail address: delrio@irnase.csic.es, The composition of pitch deposits occurring in pulp sheets and mill circuits during soda/anthraquinone pulping and elemental chlorine-free pulp bleaching of bast fibers of industrial hemp (Cannabis sativa) has been studied. Pitch deposits were extracted with acetone, and the extracts analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). Acetone extracts (15-25% of pitch deposits) were constituted by the defoamers used at the mill and by lipophilic extractives from hemp fibers. Acetone-insoluble residues (75-85% of pitch deposits) were analyzed by pyrolysis-GC/MS in the presence and absence of tetramethylammonium hydroxide. These residues were constituted by salts of fatty acids (arising from hemp fibers) with calcium, magnesium, aluminum and other cations that were identified in the deposits. It was concluded that inappropriate use of defoamer together with the presence of multivalent ions seemed to be among the causes of hemp extractives deposition in the pitch problems reported here., This study has been supported by the Spanish Ministerio de Ciencia y Tecnología (MCYT) and FEDER funds (projects 2FD97-0896-C02-02 and AGL2002-00393). A.G. acknowledges a "Ramón y Cajal" contract of the Spanish MCYT. We also thank CELESA (Tortosa, Spain) for providing the samples.