Activated sludge is widely used to treat municipal and industrial wastewater globally and the formation of activated sludge flocculates (flocs) underpins the ability to separate sludge from treated water. Despite the importance of activated sludge flocs to human civilization there have been precious few attempts to rationally design fit for purpose flocs using a bottom-up approach based on a so...

Some characteristics of Upflow Anaerobic Sludge Blanket (UASB), Expended Granule Sludge Blanket (EGSB), and Static Granular Bed Reactor (SGBR) were investigated in order to compare performances of the three and recognize advantages and disadvantages, respectively. The UASB reactor is developed in the late 1970s and became rapidly widespread due to great performances. With granules, this reactor...

EPA recently concluded limited testing of agricultural sites in Alabama where sewage sludge was applied from a local wastewater treatment plant that receives wastewater from numerous industrial sources, including facilities that manufacture and use perfluorooctanoic acid (PFOA) and other perfluorinated chemicals (PFCs). The results from this limited testing indicated elevated levels of PFCs in ...

The temperature effect on denitrification rate of a two-sludge system has been studied. An industrial high-strength wastewater and an industrial by-product containing mainly methanol, as external carbon source, were used in this study. The maximum denitrification rate (MDR) was determined at six different temperatures: 6, 8, 10, 15, 20 and 25oC in batch mode. The temperature coefficient was fou...

The disposal of domestic wastewater without any treatment into the drainage systems is considered a source of pollution threatening the population. Industrial waste water discharge to the environment is one of the environmental problems which must be controlled. Current mainstream technologies for treatment of domestic wastewater such as activated sludge and tertiary nutrient removal are too co...

Amplified ribosomal DNA restriction analysis (ARDRA) is a simple method based on restriction endonuclease digestion of the amplified bacterial 16S rDNA. In this study we have evaluated the suitability of this method to detect differences in activated sludge bacterial communities fed on domestic or industrial wastewater, and subject to different operational conditions. The ability of ARDRA to de...

Phenol and it derivatives are considered as one of the priority pollutants in waste water, because they are harmful to organisms even at very low concentrations. The control as well as removal of these organic compounds has become an important issue due to stringent measures introduced by various countries to enforce regulations concerning wastes originating from various industries. Hence, wast...

Microbial fuel cells (MFCs) are devices that exploit living microbes for electricity generation coupled to organics degradation. MFCs are expected to be applied to energy-saving wastewater treatment (WWT) as alternatives to activated-sludge reactors (ASRs). Although extensive laboratory studies have been performed to develop technologies for WWT-MFCs, limited information is available for compar...

Wastewater treatment plants (WWTPs) are a significant source for poly-/perfluoroalkyl substances (PFASs) entering the environment. The presence of PFASs in twenty-eight municipal WWTPs from eleven cites in economically developed areas of China were screened. Overall, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) were dominant in wastewater and sludge, and were not effec...

This paper reviews the sources, bioavailability and fate of heavy metals and organic contaminants in compost manure and in soils of which the manure is applied. The toxicity of heavy metals and organic compounds in soil of which would have come from applied compost is also discussed. Type of materials, their background and where collected for use in composting contribute to the sources of heavy...