A sequencing batch reactor (SBR) seeded with flocculated sludge and fed with synthetic wastewater was operated for an enhanced biological phosphorus removal (EBPR) process. Eight weeks after reactor startup, sludge granules were observed. The granules had a diameter of 0.5 to 3.0 mm and were brownish in color and spherical or ellipsoidal in shape. No significant change was observed in sludge gr...

When primary domestic sewage sludge was combined with settled sewage or secondary-treatment plant effluent, synergism resulted. The activity (measured by oxygen uptake, and the removal of Kjeldahl nitrogen and orthophosphate from solution) which resulted from incubating sludge together with settled sewage exceeded the sum of the activities when these components were incubated separately. A simi...

Despite the obvious advantages of anaerobic sludge digestion viz. sludge reduction and sustainable management, it has some drawbacks. In particular, anaerobic digestion produces a complex and unknown residue sludge which is difficult to treat and to dewater. Because dewatering mainly involves rheological solid characteristics, this paper focuses on the similarities between these residues with o...

The fate and behaviour of two groups of endocrine disrupting chemicals, steroid estrogens and nonylphenol ethoxylates, have been evaluated during the anaerobic digestion of primary and mixed sewage sludge under mesophilic and thermophilic conditions. Digestion occurred over six retention times, in laboratory scale reactors, treating sludges collected from a sewage treatment works in the United ...

Three sludge types from the same treatment stream (undigested liquid, anaerobically digested liquid and dewatered, anaerobically digested cake) were used in a field based tub study. Amendments (4, 8, and 16 Mg dry solid (ds)ha(-1)) were incorporated into the upper 15 cm of a sandy loam soil prior to sowing with rye-grass (Lolium perenne L.). Nitrogen transformations in the soil were determined ...

According to the IPCC (Intergovernmental Panel on Climate Change) guidelines, when calculating CO2 emissions, CO2 emissions from biomass should be excluded from the total amount of CO2 emissions and should be separately reported due to their “carbon neutrality”. Sewage sludge is one of the representative biomass fuels. It is mixed with fossil fuels to achieve greenhouse gas reduction or is used...

The laboratory scale studies had been carried out regarding the possibility of electron beam application for sludge hygienization. Experimental system with nozzle type sludge feeder and stainless steel belt conveyor was constructed for irradiation under continuous feeding conditions of sludge cakes with electron beam of dose rate of 40kGy/s. Survival curves of microbial population for total col...

In this paper, sliding mode control (SMC) for a bidirectional buck/boost DC-DC converter (BDC) with constant frequency in continuous conduction mode (CCM) is discussed. Since the converter is a high-order converter, the reduced-order sliding manifold is exploited. Because of right-half-plan zero (RHPZ) in the converter’s duty ratio to output voltage transfer function, sliding mode current...

A laboratory-scale microwave (MW) unit was applied to treat fresh blackwater sludge that represented fecal sludge (FS) produced at heavily used toilet facilities. The sludge was exposed to MW irradiation at different power levels and for various durations. Variables such as sludge volume and pathogen reduction were observed. The results demonstrated that the MW is a rapid and efficient technolo...