A biological nutrient removal (BNR) activated sludge (AS) scheme incorporating external nitrification in a fixed media system is evaluated. A laboratory scale investigation of the scheme indicates that it holds considerable potential for BNRAS system intensification through major reduction in sludge age and oxygen demand and significant improvement in sludge settleability. Because the BNRAS sys...

The present research aimed to characterize the potential efficiency of deferasirox in removing thallium after its administration for 30 days following two dose levels of 20 and 160 μm of thallium (III) chloride to male Wistar rats every day. After thallium administration some abnormal clinical signs such as red staining around the eyes, greenish mottling on the liver, weakness, loss of hair and...

The objective of this research was to advance a fundamental understanding of a unique post-anoxic denitrification process for achieving biological nutrient removal (BNR), with an emphasis on elucidating the impacts of surface oxygen transfer (SOT), variable process loadings, and bioreactor operational conditions on nitrogen and phosphorus removal. Two sequencing batch reactors (SBRs) were opera...

This work studies the use of biological and combined biological/enzymatic treatments in phenol degradation. The systems studied were conventional batch aerobic biological followed or preceded by enzymatic treatment. Tyrosinase extracted from the mushroom Agaricus bispora was employed. Biological treatment efficiently degraded effluents containing up to 420 mg.L of phenol, removing 97% of the CO...

The present study was conducted on removal of zinc in a continuous flow system by Aspergillus sp. during its growth. The fungal strain was isolated from industrial wastewater. The experiments under continuous culture conditions were performed in two reactors of working volume 650ml and 3 litres respectively. The experiments were conducted using sugar concentrations of 10, 15 and 20g/l and at di...

Whenever the carbon/nitrogen ratio of a domestic wastewater is too low, full denitrification is difficult to obtain and an additional source of organic carbon has to be provided. Since loading conditions may vary appreciably over the diurnal cycle, depending on the weather and sewage conditions, dosing should be controlled by an adaptive regulator to keep into account the time-varying process d...

A novel biological nitrogen removal system based on nitritation coupled with thiosulfate-driven denitritation (Nitritation-TDD) was developed to achieve a high nitrogen removal rate and low sludge production. A nitritation sequential batch reactor (nitritation SBR) and an anoxic up-flow sludge bed (AnUSB) reactor were applied for effective nitritation and denitritation, respectively. Above 75% ...

This paper presents a very useful software tool to design, simulate and optimise wastewater treatment plants. The program is called DESASS (DEsign and Simulation of Activated Sludge Systems) and has been developed by CALAGUA research group. The mathematical model implemented is the Biological Nutrient Removal Model No.1 (BNRM1) which allows simulating the most important physical, chemical and b...

ÐThe need for readily biodegradable organic matter to support denitri®cation and enhanced biological phosphorus removal (EBPR) can be satis®ed using external or internal carbon sources. This paper examines the production and removal of volatile fatty acids (VFAs), mainly acetic acid, and other hydrolyzed products from sludge using hydrothermal treatment at subcritical (<3748C) and supercritical...

Iodinated contrast media (ICM), which are used for radiological visualization of human tissue and cardiovascular system, are poorly biodegradable; hence, new methods of their removal are sought. In this study, the effectiveness of selected X-ray ICM removal by means of UV and UV/TiO2 pretreatment processes from synthetic hospital wastewater was demonstrated. The following compounds were investi...