This study was conducted to evaluate the effect of commercially available engineered iron oxide nanoparticles coated with a surfactant (ENPFₑ₋ₛᵤᵣf) on effluent water quality from a lab-scale sequencing batch reactor as a model secondary biological wastewater treatment. Results showed that ∼8.7% of ENPFₑ₋ₛᵤᵣf applied were present in the effluent stream. The stable presence of ENPFₑ₋ₛᵤᵣf was confirmed by analyzing the mean particle diameter and iron concentration in the effluent. Consequently, aqueous ENPFₑ₋ₛᵤᵣf deteriorated the effluent water quality at a statistically significant level (p < 0.05) with respect to soluble chemical oxygen demand, turbidity, and apparent color. This implied that ENPFₑ₋ₛᵤᵣf would be introduced into environmental receptors through the treated effluent and could potentially impact them.

MOON (Mediterranean Operational Oceanography Network http://www.moon-oceanforecasting.eu) provides near-real-time information on oil-spill detection (ocean color and SAR) and predictions [ocean forecasts (MFS and CYCOFOS) and oil-spill predictions (MEDSLIK)]. We employ this system to study the Lebanese oil-pollution crisis in summer 2006 and thus to assist regional and local decision makers in Europe, regionally and locally. The MEDSLIK oil-spill predictions obtained using CYCOFOS high-resolution ocean fields are compared with those obtained using lower-resolution MFS hydrodynamics, and both are validated against satellite observations. The predicted beached oil distributions along the Lebanese and Syrian coasts are compared with in situ observations. The oil-spill predictions are able to simulate the northward movement of the oil spill, with the CYCOFOS predictions being in better agreement with satellite observations. Among the free MEDSLIK parameters tested in the sensitivity experiments, the drift factor appears to be the most relevant to improve the quality of the results.

Mature landfill leachate contains some macromolecular organic substances that are resistant to biodegradation. The photocatalytic process helps to enhance biodegradability of landfill leachate. Batch experiments were employed to determine the optimum conditions for removal of organic matter by UV-TiO2 photocatalysis. Under optimum conditions, the removal of chemical oxygen demand (COD), dissolved organic carbon (DOC), biological oxygen demand (BOD), and color was determined. Moreover, gas chromatography coupled with mass spectrometry (GC/MS) was used to analyze the organic matter in the treated leachate before and after treatment by the photocatalysis. The experimental results indicated that the removal of COD, DOC, and color by UV-TiO2 photocatalysis could reach above 60%, 70% and 97%, respectively. Under optimal conditions, the ratio of biological oxygen demand (BOD)/chemical oxygen demand (COD) was elevated from 0.09 to 0.39, representing substantial improvement in biodegradability. GC/MS analysis revealed that 37 out of 72 kinds of organic pollutants in the leachate remained after 72 h treatment. Esters were produced during photocatalytic process and ketones, hydrocarbons, aromatic hydrocarbons, hydroxybenzenes, and acids were easier to be degraded during photocatalytic oxidation processes. The UV-TiO2 photocatalysis systems proposed may be a cost-effective approach for pre-treatment of landfill leachate.

Sulphuric acid-modified bagasse has been used as low-cost adsorbent for the removal of methylene blue (MB) dye from aqueous solution. In order to remove organic compounds that contribute to chemical oxygen demand (COD), pretreatment with thorough washing of adsorbent using boiling distilled water was performed instead of conventional washing using distilled water at room temperature only. This has resulted in the highest efficiency of color removal of 99.45% and COD reduction of 99.36% for MB dye solution at pH 9. Effects of initial pH, dye concentration, adsorbent dosage, temperature, and contact time have been studied. The adsorption of MB dye was pH dependent. Langmuir and Freundlich isotherm models were tested on the adsorption data. The kinetic experimental data were analyzed using pseudo-first order, pseudo-second order, and the intraparticle diffusion model in order to examine the adsorption mechanisms. The adsorption process followed the Langmuir isotherm as well as the Freundlich isotherm and pseudo-second-order kinetic model. The process was found to be endothermic in nature.

Wastewaters from pulp and paper mills are highly toxic and around 250 xenobiotic compounds have been reported in the effluents. Tannic acid degrading bacterium, Enterobacter sp. was isolated from soil by tannic acid enrichment. This isolate was used for bioremediation of pulp and paper mill effluents. Parameters like temperature, agitation, inoculum size and treatment duration were optimized by using Qualiteck-4 software. Reduction in lignin 73% and colour up to 82% was also observed. Encouraging results were observed is reduction of COD, BOD with 16-h retention time in batch culture.

We have examined populations of brown trout in low-conductivity mountain lakes (5.0–13.7 μS/cm and 0.14–0.41 mg/l Ca) in southwestern Norway during the period 2000–2010. Inlets to the lakes were occasionally even more dilute (2007; conductivity = 2.9–4.8 μS/cm and Ca = 0.06–0.17 mg/l). The combination of pH and conductivity was the best predictor to fish status (CPUE), indicating that availability of essential ions was the primary restricting factor to fish populations in these extremely diluted water qualities. We suggest that conductivity <5 μS/cm is detrimental to early life stages of brown trout, and subsequently that there are lakes in these mountains having too low conductivity to support self-reproducing trout populations. Limited significance of alkalinity, Ca, Al, and color suggests that effects of ion deficit apparently overruled the effects of other parameters.

Biosorption has potential to be an economical colour removal technology. As such, the colour removal potential of inactivated Aspergillus niger biomass was investigated for the treatment of activated sludge-treated pulp mill effluent from a northern bleached softwood kraft mill. Biomass pretreatment methods, effects of initial pH of the effluent and preparative biomass washing methods were examined. The most effective pretreatment method was found to be simple autoclaving of the biomass and this approach was applied in subsequent kinetic and isotherm batch studies. It was also found that the pH of the wastewater prior to addition of the biomass affected the biosorption rate and the solubility of chromophores in pulp mill effluent. The results also indicated that biomass washing methods reduced the quantity of organic matter leached from the fungal biomass during application. The kinetic study revealed that colour removal by biosorption occurred most readily in the first 8 h and could be described adequately by both the Lagergren and Ho et al. models. The maximum colour removal was over 900 TCU, with a biomass dose of about 20 g/L. The isotherm study data were fitted with the BET isotherm model. The results indicated that adsorption occurred in a multi-layer fashion and that physical adsorption was the main mechanism contributing to the biosorption. Therefore, dead A. niger biomass was concluded to be a promising alternative for colour removal from pulp mill effluent.