Wastewater

About: Wastewater is a research topic. Over the lifetime, 92512 publications have been published within this topic receiving 1256590 citations. The topic is also known as: waste water.

Antifouling membranes for oily wastewater treatment: Interplay between wetting and membrane fouling

Abstract: Oily wastewater is an extensive source of pollution to soil and water, and its harmless treatment is of great importance for the protection of our aquatic ecosystems. Membrane filtration is highly desirable for removing oil from oily water because it has the advantages of energy efficiency, easy processing and low maintenance cost. However, membrane fouling during filtration leads to severe flux decline and impedes long-term operation of membranes in practical wastewater treatment. Membrane fouling includes reversible fouling and irreversible fouling. The fouling mechanisms have been explored based on classical fouling models, and on oil droplet behaviors (such as droplet deposition, accumulation, coalescence and wetting) on the membranes. Membrane fouling is dominated by droplet-membrane interaction, which is influenced by the properties of the membrane (e.g., surface chemistry, structure and charge) and the wastewater (e.g., compositions and concentrations) as well as the operation conditions. Typical membrane antifouling strategies, such as surface hydrophilization, zwitterionic polymer coating, photocatalytic decomposition and electrically enhanced antifouling are reviewed, and their cons and pros for practical applications are discussed.

Anammox growth on pretreated municipal wastewater.

Abstract: Autotrophic nitrogen removal from municipal wastewater enables development of energy autarkic wastewater treatment plants. In this study we report the evaluation of the anammox process in a granular sludge fluidized bed lab-scale reactor continuously fed with the actual effluent of the A-stage of the WWTP of Dokhaven, Rotterdam. The reactor was anoxic, and nitrite was dosed continuously to support anammox activity only. The system was operated for more than ten months at temperatures between 20 and 10 °C. COD was also consumed during the process, but heterotrophs could not outcompete anammox bacteria. Volumetric N-removal rates obtained were comparable or higher than those of conventional N-removal systems, with values higher than 0.4 g-N L(-1) d(-1) when operated at 10 °C. The biomass specific N-removal rate at 10 °C was on average 50±7 mg-N g-VSS(-1) d(-1) during the last month of operations, almost two times higher than previously reported activities at this temperature. FISH analysis revealed that the dominant anammox species was Candidatus Brocadia Fulgida throughout the experimentation. Evidence for growth of anammox bacteria at mainstream conditions was demonstrated for the entire temperature range tested (10-20 °C), and new granules were shown to be actively formed and efficiently retained in the system.