in this research the operation of fixed activated sludge system for treatment of wastewater containing heavy metal compounds, by use of fas pilot ,a plaxy glass tank with three section; these section are downward-flow aerated reactor, upward-flow aerated reactor and gravity sediment unit, length and width and height of each part was respectively 15.7cm, 31.5cm , 51.5 cm and feeding with the syn...

Aerated-anoxic processes operate under the principle that small additions of oxygen to an anoxic reactor induce simultaneous nitrification and denitrification. In these systems, ammonia oxidation in the anoxic zone can easily account for 30-50% of the total nitrification in the reactor, even though the dissolve oxygen concentration is usually below detection limit. To investigate whether the ni...

evaluation and modeling of the wastewater treatment plants (wwtp) have to be based on thefact that the pollutant concentrations and flow rates change constantly. in addition, different approaches mustused due to there are different processes in a wwtp. a mexican petrochemical complex has a wwtp thatprocesses wastewaters from several petrochemical plants, where the flow rates and pollutant conce...

A submerged biological filter packed with clayey schists from brick industrial waste as support material was used to treat landfill leachate. The pilot-scale plant consisted of two separated reactors, running in aerated and non-aerated conditions respectively. The leachate was taken from a landfill in Granada (southeast Spain) and was considered as partially stabilized with average chemical oxy...

a down-flow hanging sponge (dhs) reactor has been developed for sewage treatment, mainly in developing countries. this novel reactor employs polyurethane sponge material as a support medium, which promises a proliferation of a large amount of biomass, offering excellent pollutant removal capability. three types of sponge medium were evaluated with respect to water distribution and oxygen mass t...

Acrylonitrile is used as the main raw material for manufacturing acrylonitrile butadiene styrene resin. It is usually found as pollutant in the petrochemical wastewater. In this research an aerated submerged fixed-film reactor was developed to treat a synthetic acrylonitrile butadiene styrene unit wastewater containing acrylonitrile. Laboratory experiments were conducted using a bioreactor with...

Mixing is a widely practiced operation to effect distribution, intermingling and homogeneity of matter. Stirred tanks with different geometries (such as in main container tanks, impellers, baffles, etc.) are also widely used to mix different materials. The forces applied by impellers develop overall circulation or bulk flow. Superimposed on this flow pattern, there are turbulent eddies and also...

Partial nitrification techniques, such as the continuously aerated SHARON process, have been denoted for quite a while as very promising for improved sustainability of wastewater treatment. Combination of such a SHARON process with the Anammox process, where ammonium is oxidised with nitrite to nitrogen gas under anoxic conditions, leads to cost-efficient and sustainable nitrogen removal from c...

In this study, an innovative aerobic/anoxic sludge bed bioreactor with two feeding regimes, continuous-fed (an up-flow sludge bed reactor (USBR)) and batch fed (sequencing batch reactor (SBR)), was evaluated for the treatment of an industrial estate wastewater with low BOD(5)/COD ratio. The process performance in the two regimes was compared. Two numerical independent variables (retention/react...