Search results for "Effluent"
showing 10 items of 235 documents
Do historical sediments of pulp and paper industry contribute to the exposure of fish caged in receiving waters?
2011
Field experiments were conducted in early summer 2004 by caging brown trout (Salmo trutta m. lacustris) in Southern Lake Saimaa (SE Finland) for 10 days. Cages were positioned into two depths at four distances (5 to 17 km) from the pulp and paper mill; one set with direct contact to the sediment and other locating at the three meters' depth from the water surface. Resin acids were measured from sediment, water, and fish bile. Possible toxicities were investigated by measuring liver EROD-activity, HSP70-protein, and gene expression profiles by microarray. The concentration of resin acids in the sediment showed clear gradient along the distance from the mill, and their concentrations in water…
Expression of the Vitellogenin Gene in the Liver of Juvenile Whitefish (Coregonus lavaretus L. s.l.) Exposed to Effluents from Pulp and Paper Mills
1999
Juvenile whitefish (Coregonus lavaretus L. s.l.) were exposed by caging in the field to diluted effluents from three operating pulp, paper, and paperboard mills in Southern Lake Saimaa, Finland. The expression of the vitellogenin gene, used as a biomarker of estrogenic contamination of effluents, was measured using a Northern blotting method. Increased mRNA levels, the most specific and reliable evidence for estrogen receptor-mediated actions in vivo, were found in fish caged in the vicinity of one of three mills studied. This mill was found to discharge wood-derived compounds, such as sterols and resin acids, into Lake Saimaa in amounts considerably exceeding those from the other two mills…
Altered Challenge Response in Whitefish Subchronically Exposed in Areas Polluted by Bleached Kraft Mill Effluents
1999
Exposure to impaired water quality, as in bleached kraft mill effluents (BKMEs), has recently been demonstrated to impair the ability of fish to elicit an acute stress response. Acute stress caused by catching is, in most field studies, an unavoidable incident that may markedly affect physiological functions. Consistently, dissimilar stress responses to catching procedures in exposed and reference animals may lead to altered results. In this study, juvenile whitefish (Coregonus levaretus) were caged for 30 days in two reference areas and three areas affected by different BKMEs, and the immediate effects of low-level handling on physiological functions in four periods within an hour of the s…
Effect of pulp and paper mill effluent (BKME) on physiological parameters of roach (Rutilus rutilus) infected by the digenean Rhipidocotyle fennica.
2002
Physiological parameters were measured after experimental infection of roach (Rutilus rutilus L.) with Rhipidocotyle fennica Gibson, Valtonen et Taskinen, 1992 (Digenea) cercariae. The fish were caught from two lakes: a eutrophic bleached kraft mill effluent (BKME)-contaminated lake and an oligotrophic unpolluted lake. The intensity of infection was followed up to 10 days post infection (p.i.) and physiological parameters indicating non-specific stress responses and the condition of fish were examined simultaneously. The mean abundance, the number of parasites per fish, of R. fennica was significantly higher in the fish from the contaminated water during the first two days p.i., probably re…
PDMS membranes for feasible recovery of dissolved methane from AnMBR effluents
2020
[EN] This study aimed to evaluate the feasibility of degassing membrane (DM) technology for recovering dissolved methane from AnMBR effluents. For that purpose, a PDMS membrane module was operated for treating the effluent from an AnMBR prototype-plant, which treated urban wastewater (UWW) at ambient temperature. Different transmembrane pressures and liquid flow rates were applied for evaluating methane recovery efficiency. Maximum methane recoveries were achieved when increasing the vacuum pressure and reducing the liquid flow rate, reaching a maximum methane recovery efficiency of around 80% at a transmembrane pressure (TMP) of 0.8 bars and a treatment flow rate (Q(L)) of 50 L h(-1). The …
A multicommutated flow system for determination of bismuth in milk shakes by hydride generation atomic fluorescence spectrometry incorporating on-lin…
2004
Abstract A highly sensitive method was developed for determination of bismuth in milk shakes by multicommutation hydride generation atomic fluorescence spectrometry (HG-AFS) based on off-line sonication for 10 min with aqua regia 8% (v/v) and on-line waste treatment. The instrumentation and chemistry variables were studied in order to provide the best performance. The limit of detection in the original samples, established for a probability level of 99.6% (k = 3), was 1.67 ng/g Bi. The method provides a fast alternative in control analysis with a sampling throughput of 72 h as compared with 31 h obtained by the classical continuous measurement. Additionally, multicommutation reduces waste g…
Dense jet modelling applied to the design of dense effluent diffusers
2004
A model aimed at predicting the behavior of inclined dense jets in a stagnant environment was proposed. The model takes into account four jet parameters (flow rate, density, inclination and diameter) and results in a set of algebraic and ordinary differential equations, which are easily solved by simple (standard) numerical methods. Model results include information on the trajectory, spreading and dilution of the inclined dense jets. Model predictions were compared with experimental data obtained with different nozzle diameters, jet flow rates, jet densities and nozzle inclinations. Despite the wide range encompassed by the experimental data analyzed, model predictions were always found to…
Greenhouse gases from membrane bioreactors: New perspectives on monitoring and mathematical modeling
2020
Abstract The awareness that the wastewater sector represents a significant source of greenhouse gas emission has increased, and is the awareness is evident based on the numerous research papers published in technical literature in the last 10 years. This chapter is aimed at providing a timely overview on greenhouse gas production and emission from membrane bioreactors. Specifically, this chapter dedicates particular attention to nitrous oxide (N2O), considering both experimental and mathematical modeling approaches. Referring to the experimental data, the observed results highlighted the significant contribution of the aerated compartments toward nitrous oxide emission as well as the import…
Monitoring and Origin of Polycyclic Aromatic Hydrocarbons (PAHs) in Effluents from a Surface Treatment Industry
2017
In Europe, polycyclic aromatic hydrocarbons (PAHs) are a source of concern due to their toxic effects and are considered as priority pollutants by water authorities. In this study, we reported the ...
Removal of toxic pollutants from pulp mill effluents by electrocoagulation
2011
This study investigated the effect of electrocoagulation treatment on toxic pollutant removal from pulp mill effluents. Synthetic wastewaters containing wood rosin and copper or pure resin acids were used to investigate the removal of resin acids and copper by electrocoagulation. Removal of pollutants by electrocoagulation was also tested with real debarking effluent. In this study, statistical experimental design and partial least squares modeling were used to investigate the effect of initial pH, current (current density) and treatment time. Electrocoagulation and subsequent filtration removed resin acids and copper from the synthetic wastewaters with high efficiency. Toxicity to algae (P…