Search results for "disposal"
showing 10 items of 1300 documents
Anaerobic degradation of glycol ether-ethanol mixtures using EGSB and hybrid reactors: Performance comparison and ether cleavage pathway.
2017
Abstract The anaerobic biodegradation of ethanol-glycol ether mixtures as 1-ethoxy-2-propanol (E2P) and 1-methoxy-2-propanol (M2P), widely used in printing facilities, was investigated by means of two laboratory-scale anaerobic bioreactors at 25oC: an expanded granular sludge bed (EGSB) reactor and an anaerobic hybrid reactor (AHR), which incorporated a packed bed to improve biomass retention. Despite AHR showed almost half of solid leakages compared to EGSB, both reactors obtained practically the same performance for the operating conditions studied with global removal efficiencies (REs) higher than 92% for organic loading rates (OLRs) as high as 54 kg of chemical oxygen demand (COD) m−3 d…
Effect of long residence time and high temperature over anaerobic biodegradation of Scenedesmus microalgae grown in wastewater
2018
[EN] Anaerobic digestion of indigenous Scenedesmus spp. microalgae was studied in continuous lab-scale anaerobic reactors at different temperatures (35 degrees C and 55 degrees C), and sludge retention time - SRT (50 and 70 days). Mesophilic digestion was performed in a continuous stirred-tank reactor (CSTR) and in an anaerobic membrane bioreactor (AnMBR). Mesophilic CSTR operated at 50 days SRT only achieved 11.9% of anaerobic biodegradability whereas in the AnMBR at 70 days SRT and 50 days HRT reached 39.5%, which is even higher than the biodegradability achieved in the thermophilic CSTR at 50 days SRT (30.4%). Microbial analysis revealed a high abundance of cellulose-degraders in both re…
Bacterial diversity associated with poplar trees grown on a Hg-contaminated site: Community characterization and isolation of Hg-resistant plant grow…
2018
International audience; Industrial waste dumps are rarely colonized by vegetation after they have been abandoned, indicating biological infertility. Revegetation of industrial tailings dumps is thus necessary to prevent wind erosion, metal leaching and has been shown to restore soil functions and ecosystem services. However, little is known about the microbial colonization and community structure of vegetated tailings following the application of restoration technologies. In this study, we investigated the rhizosphere and phyllosphere bacterial communities of a poplar tree plantation within a phytomanagement-based restoration program of a Hg-contaminated site. We used Illumina-based sequenc…
Bacterial community structure and removal performances in IFAS-MBRs: A pilot plant case study
2017
Abstract The paper reports the results of an experimental campaign carried out on a University of Cape Town (UCT) integrated fixed-film activated sludge (IFAS) membrane bioreactor (MBR) pilot plant. The pilot plant was analysed in terms of chemical oxygen demand (COD) and nutrients removal, kinetic/stoichiometric parameters, membrane fouling and sludge dewaterability. Moreover, the cultivable bacterial community structure was also analysed. The pilot plant showed excellent COD removal efficiency throughout experiments, with average value higher than 98%, despite the slight variations of the influent wastewater. The achieved nitrification efficiency was close to 98% for most of the experimen…
Influence of food waste addition over microbial communities in an Anaerobic Membrane Bioreactor plant treating urban wastewater
2018
[EN] Notorious changes in microbial communities were observed during and after the joint treatment of wastewater with Food Waste (FW) in an Anaerobic Membrane Bioreactor (AnMBR) plant. The microbial population was analysed by high-throughput sequencing of the 16S rRNA gene and dominance of Chloroflexi, Firmicutes, Synergistetes and Proteobacteria phyla was found. The relative abundance of these potential hydrolytic phyla increased as a higher fraction of FW was jointly treated. Moreover, whereas Specific Methanogenic Activity (SMA) rose from 10 to 51 mL CH4 g(-1) VS, Methanosarcinales order increased from 34.0% over 80.0% of total Archaea, being Methanosaeta the dominant genus. The effect o…
Environmental metabarcoding reveals contrasting microbial communities at two poplar phytomanagement sites
2016
The aim of the present study is to deepen the current understanding of the microbial communities at two poplar phytomanagement sites to reveal the environmental factors that drive the abundance, diversity and composition of microbial communities. A soil analysis revealed that the two soils displayed contrasting physico-chemical characteristics, with significant lower pH and higher Cd, Zn and Mn CaCl2-extractable fractions at Leforest site, compared with Pierrelaye site. The fungal and bacterial community profiles in the poplar roots and soils were assessed through Illumina MiSeq sequencing. Diversity indices and β-diversity measures illustrated that the root microbial communities were well …
Effects of UV filter 4-methylbenzylidene camphor during early development of Solea senegalensis Kaup, 1858
2018
Abstract The inclusion of organic UV filters in personal care products (PCPs) has increased in recent years. 4-Methylbenzylidene camphor (4MBC) is one of the most used UV filters, and thus it is commonly found in aquatic ecosystems, with proved negative effects on aquatic organisms. Effects on early life stages of marine vertebrates are largely unknown. Therefore, the main goal of this work was to evaluate 4MBC effects on Senegalese sole (Solea Senegalensis Kaup, 1858) larvae at different levels of biological organization. S. senegalensis were exposed to increasing concentrations of 4MBC from egg stage until 96 h. Mortality, growth, malformations, behaviour and biochemical responses, includ…
Chemometric Study on Alkaline Pre-treatments of Wood Chips Prior to Pulping
2016
Alkaline pre-treatments were performed for the production of organics-containing effluents from silver/white birch (Betula pendula/pubescens) and Scots pine (Pinus sylvestris) chips prior to chemical pulping. Pre-treatment conditions were varied with respect to time (from 30 min to 120 min), temperature (130 °C and 150 °C), and alkali charge (1, 2, 3, 4, 6, and 8% of NaOH on oven-dried wood). The analytical data (total content, weight average molar mass, and molar mass distribution) on dissolved lignin were subjected to principal component analysis to examine the relationship between molar mass and molar mass distributions in lignin removed from different wood species under varying alkaline…
Predictors of Hepatitis B Surface Antigen Titers two decades after vaccination in a cohort of students and post-graduates of the Medical School at th…
2017
Introduction and objective. The introduction of a vaccine against hepatitis B virus (HBV) for newborn babies in Italy in 1991, extended to 12-year-old children for the first 12 years of application, has been a major achievement in terms of the prevention of HBV infection. The objective of this study was to analyse the long-term immunogenicity and effectiveness of HBV vaccination among healthcare students with different working seniorities. Materials and method. A cross-sectional observational study of undergraduate and postgraduate students attending the Medical School of the University of Palermo was conducted from January 2014 – July 2016. HBV serum markers were performed with commercial …
Investigating the emerging role of comparative proteomics in the search for new biomarkers of metal contamination under varying abiotic conditions
2016
13 pages; International audience; This study aims at investigating the potential use of comparative proteomics as a multi-marker approach of metal contamination, taking into account the potential confounding effect of water temperature. The major objective was to identify combinations of proteins specifically responding to a given metal, even if included in a metal mixture. The diagnostic approach was performed via the comparative analysis of protein expression on spot mapping provided by adult males of Gammarus pulex (Amphipoda, Crustacea) respectively exposed to arsenate (As), cadmium (Cd) or a binary mixture of these metals (AsCd) at three realistic temperatures (5, 10 and 15 °C). Proteo…