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The United Arab Emirates (UAE) is one of the leading countries in the per capita bottled water consumption. This seems to be in controversy with adherences of local water authorities to stringent municipal water standards. A public survey (n= 891) was conducted to ascertain the perception of people in the country regarding bottled and tap water quality. The survey form was formulated based on the stated preference approach and was furnished in both Arabic and English languages. Some questions in the survey form require rating the quality of tap water and identifying the type of water the respondent drinks. For respondents who usually drink bottled water, they were asked to choose the reason(s) why they usually drink bottled water. Those who drink tap water more often were similarly asked to choose the reason(s) why they prefer tap water to bottled water. The study revealed that a large fraction of the UAE residents classify the quality of tap water as either good or excellent, yet many of them drink bottled water. This could be attributed in part to the high standard of living where the cost of bottled water is considered by the majority of the respondents as affordable. Other influential factors include the belief that bottled water has a better taste and concerns about tap water contamination. The latter may stem from the perception that water is not sufficiently treated or contamination is induced into the water from the distribution system or the in-house storage tanks. The study shows that more people in the UAE will drink tap water if relevant authorities provide information about tap water quality and if regular inspections and cleaning of the in-house storage tanks is conducted.

Sequencing batch reactor (SBR) is a time-oriented wastewater treatment (WWT) system in a single reactor with flow and energy input according to the predetermined operational cycle time. The treatment efficiency of SBR varies with the duration of the cycle time, which affects the reactor size and hence the cost of WWT plant. This paper presents an experimental study in a bench scale SBR model with a working volume of 15 L with an onjective to determine  the optimum cycle time for simultaneous removal of carbon and nutrient from the dairy wastewater. Using the equalized dairy wastewater experiments with four cycle times of 8 h, 6 h, 4 h and 2 h were conducted and the effluent concentrations were compared to the effluent standards. In conclusion, the data suggest the SBR process with 6 h cycle time as the optimum cycle time for treating dairy wastewater for simultaneous carbon and nutrient removal.

In this study, the photocatalytic degradation of two biologically treated textile finishing wastewater was investigated using powdered TiO₂ and ZnO catalysts with UV-A lamp irradiation. Photodegradation and photodecolorization of the samples real textile industrial wastewater is observed directly proportional to pH and catalyst concentrations. Optimum catalyst concentration was found as 2 g l^-1 in both catalysts. COD removal in TiO₂ assisted system was obtained two fold higher than ZnO assisted system depending characteristics of the wastewater samples. Optimum pH values were determined to be 5 and 9 for TiO₂ and ZnO assisted systems respectively. A COD removal of 45% and 23% were obtained using and ZnO catalysts respectively during 3 h irradiation. The effluents of photocatalytic treated samples using both catalysts displayed no acute toxicity at the end of 3 h irradiation time at optimum experimental conditions.  Results, in conclusion, revealed that both TiO₂ and ZnO catalysts were found to be very effective in color removal and provided safe and proper effluents to meet discharge limits, even reuse guideline values. 

ISC-Aermod view dispersion model has been used to study the ground level concentration of hydrocarbon (HC). The purpose was to predict the air quality effects from off-grid diesel power generators operated by a textile factory in Lagos, Nigeria on its host airshed. Emissions from 22 point sources in 5 sections of the factory were considered with 6 different scenarios. 4 years of hourly meteorological observations were used for the investigation of dispersion. The model output showed the highest value of maximum ground level concentration at 90 m south east of the factory. The predicted impact using the worst case scenario showed that the ambient HC of the host air shed will change by 0.01-0.05% of Nigeria’s Federal Ministry of Environment (FMENV) standard. HC emissions from factory will not significantly affect the host air shed as the maximum concentrations from the worst case scenario were still lower than the national standard. However, since emissions from other factories will also be released into the same host environment, an integrated approach factoring the contributions from other factories should be employed in host air quality management.