The influence of sludge age on granular sludge formation and microbial population dynamics in a methanol- and acetate-fed aerobic granular sludge system operated at 35°C was investigated. During anaerobic feeding of the reactor, methanol was initially converted to methane by methylotrophic methanogens. These methanogens were able to withstand the relatively long aeration periods. Lowering the a...

In this paper a new model, tailor-made for nutrient deficient aerobic COD removal, is presented. The Activated Sludge Model No. 1 is chosen as a basis for model development. The original model is extended to include (1) phosphorus state variables; (2) phosphorus and nitrogen limited heterotrophic growth and (3) an additional active biomass component to model predation by higher-order organisms,...

Simulation-based design and analysis of biotreatment systems depends to a great extent on the accuracy of the model parameters used. In many cases, site-specific parameter estimates are not available and parameter values recommended in the literature are adopted along with a measure of judgment to account for bioprocess uncertainty. To better quantify process certitude associated with this appr...

In this study biomass acclimation in a side stream partial nitrification sequencing batch reactor (SBR) was performed under optimum conditions (T 30ºC, SRT 9± 1 days and hydraulic retention time (HRT) 1.2 day). Excess sludge for solids retention time (SRT) regulation was added to another batch reactor (main stream) which performed under different conditions for partial nitrification evaluation ...

Anaerobic digestion of sludge not only decreases the mass/volume of sludge, but also increases the production of energy-rich biogas. The effects of a thermal hydrolysis process (THP) on the solubilization of main organics of sludge, as well as the performance of the followed biochemical methane potential (BMP) tests under mesophilic condition (35 C), were systematically evaluated. Organic compo...

Removal efficiency of COD, NH4-N and PO4-P and NO3-N in five step SBR processes is widely influenced by hydraulic retention time of Anaerobic/Anoxic/Aerobic/Anoxic/Aerobic step of this system where the hydraulic retention time in each step is influence directly on removal efficiency of this system therefore the operator of this system cannot control on this system without experience or a contro...

Pharmaceuticals and personal care products (PPCPs) represent pollutants of emerging concern, originating in surface and drinking waters largely from their persistence in wastewater effluent. Accordingly, a wealth of recent investigations has examined PPCP fate during wastewater treatment, focusing on their removal during conventional (e.g., activated sludge) and advanced (e.g., ozonation and me...

Electrochemically generated iron can remove most contaminants present in water and wast water, by precipitation, adsorption, electrostatic interaction, and complex formation (generally called electrocoagulation-EC). In the present paper, pretreatment of brackish water having high total hardness (TH), alkalinity (A),  and Cl¯ ions, is studied by application of a DC-electrical current ot the ...