The tube flocculator is used to study how fluid shear levels affect the settling properties of a flocculated alum-kaolin suspension. FReTA is employed to quantitatively compare the effects of varying fluid shear and hydraulic residence time on the sedimentation velocity distributions and the post-sedimentation residual turbidities of flocculated suspensions formed in the tube flocculator. Resul...

For one space dimension, the phenomenological theory of sedimentation of flocculated suspensions yields a model that consists of an initial-boundary value problem for a second order partial differential equation of mixed hyperbolic–parabolic type. Due to the mixed hyperbolic-parabolic nature of the model, its solutions may be discontinuous and difficulties arise if one tries to construct these ...

the present work has been performed to eliminate sewage dry sludge of alborze city wastewater treatment plant by using them as fine aggregate in concrete. on this basis, at first the selected dry sludge was analyzed for xrd and xrf for crystalline phases and chemical composition, respectively. the results showed that more than 50% of the sludge is formed of sio2 and it had more than 20% organic...

Different methods of urban sewage sludge energy recovery such as burning, gasification, pyrolysis and digestion based on the net energy production efficiency, advantages and disadvantages and complexity of these processes have been investigated in this article. The best method for energy production from sludge was selected among different methods according to energy and the amount of the greenh...

One of the potential options for sewage sludge as an alternative organic material is fertilization energy crops. To evaluate effect granulated and mineral N60P60K60 on common osier’s (Salix viminalis L.) biomass productivity soil parameters, field trials were held in Western Lithuania’s naturally acidic Retisol (WB 2014; pHKCl 4.35–4.58). After four years cultivation dependent type, osier dry m...

background: the biological solids produced during wastewater treatment processes are called sludge. as sludge contains various sickening microorganisms such as pathogens, organic and inorganic substances and has adverse effects on human and environment, therefore it should be treated and processed entirely prior to disposal and then disposed in line to the environmental regulations. thermal tre...

In the present study, sludge from a steel wastewater treatment plant (SWWTP) was analyzed regarding its physicochemical characteristics and metal contents, and disposal options. For these purposes, grab sampling was used to collect 18 slurry and 18 cake sludge samples in 6 mouth (May-October 2012). Mann-Whitney U test, one sample T-test and Wilcoxon signed rank test were applied to analyze the ...

The present disposal routes of sewage sludge represent a critical environmental issue in Egypt. Recently, there has been an increasing concern about sewage sludge management due to the environmental risks, which resulted from the fast expansion of wastewater treatment plants without equal attention in dealing with the produced sludge. This paper discusses the current situation of sewage sludge ...