Seeding of nitrifying bacteria into the activated sludge process may decrease the necesary volume needs for a stable nitrification process. Both theoretical and experimental studies were carried out in order to evaluate the effects of seeding. A model was developed for prediction of the effects of seeding of nitrifying bacteria from a separate stage into the activated sludge process. Seeding te...

In Hong Kong, landfill dumping has been a main approach for municipal solid wastes disposal and will be continued in the near future. However, gaseous emission from municipal waste may causes offensive odours and disturbs the neighbours around landfill sites. Usually there are not enough buffer zones between landfill sites and the nearest sensitive receptors due to a land restriction in Hong Ko...

introduction :by ever-increasing of population, shortage of water resources and the necessity of wastewater treatment, huge volumes of sludge that is a byproduct of wastewater treatment, requires to be disposed in environmentally secure ways. the target of specifying strategic preferences of reuse of sludge has been to find the correct way of disposal or beneficial use of sludge. material and m...

background: phytoremediation is one of the methods used to remove contaminants and while being simple, cheap and efficient, does not cause environmental deterioration. the aims of this study were phytoremediation of soil contaminated by cd, the simultaneous survey of the influence of different electrical conductivity values, and comparison of two soil amendments including sludge and municipal c...

Currently, nitritation-anammox (anaerobic ammonium oxidation) bioreactors are designed to treat wastewaters with high ammonium concentrations at mesophilic temperatures (25 to 40°C). The implementation of this technology at ambient temperatures for nitrogen removal from municipal wastewater following carbon removal may lead to more-sustainable technology with energy and cost savings. However, t...

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...

The rheological characteristics of digested sludge are severely temperature dependent. An effect of temperature on rheological properties of digested sludge is partially irreversible. In this paper, the effects of temperature change and thermal history on viscosity of digested sludge were studied using a stress-controlled rheometer which was connected to a temperature controlled water bath. Dig...

16 Municipal sludge from wastewater treatment plants is a promising lipid feedstock for 17 biodiesel production as it contains a significant amount of lipids. However, the energy 18 necessary to remove its high water content is a major inconvenience for scaling up 19 because of the high associated cost. In addition, the expensive conventional sludge 20 drying methods are not effective enough fo...

Abstract—In recent decades with the development of technology and lack of food sources, sewage sludge in production of human foods is inevitable. Various sources of municipal and industrial sewage sludge that is produced can provide the requirement of plant nutrients. Soils in arid, semi-arid climate of central Iran that most affected by water drainage, iron and zinc deficiencies, using of sewa...

Saline soil was amended with 13.3 and 26.6 g kg of Municipal Solid Waste (MSW) compost or sewage sludge, and arylsulphatase (ARY), phosphatase (PHO), dehydrogenase (DEH), β-glucosidase (β-GLU), urease (URE) and catalase (CAT) activities as well as physical-chemical properties were determined after 70 day of incubation under laboratory conditions. MSW compost and sewage sludge significantly impr...