Sewage sludge-amended soils may alter their ability to adsorb heavy metals over time, due to the decomposition of sludge-borne organic matter. Thus, we studied Cd, Ni, and Zn adsorption by a sewage sludge-amended soil (Typic Xerofluvent) before and after one-year incubation in both monometal and competitive systems. In the monometal system, the order of decreasing sorption was Zn>Cd>Ni. Competi...

The cell voltage and power performance of a microbial fuel cell utilizing waste carbohydrate as a fuel, that does not use a mediator, catalysts or a proton exchange membrane, is reported. Tests were conducted with the cell operated essentially as a battery using manure sludge as fuel and with oxygen reduction in an aqueous solution. Using carbon cloth as anode and cathode, the cell produced pea...

Abstact: The aim of the research project was to carry out the co-digestion of organic fraction of solid municipal waste in the form of source separated kitchen waste and sewage sludge. The influence of the kitchen waste as a co-substrate on the stability and efficiency of the process was determined. Mesophilic fermentation (36 ̊C) was conducted for sewage sludge as well as mixtures of sewage slu...

Efforts have been made in this study to stabilize the sewage sludge mixed with sugarcane trash in four different proportions: 20% (T(1)); 40% (T(2)); 60% (T(3)) and 80% (T(4)), under laboratory conditions using epigeic earthworm (Oligochaeta) Eisenia fetida. The composting potential of worm was also evaluated in 100% sewage sludge treatment (T(5)). The changes in chemical properties of substrat...

The degradation of sludge solids in an insulated reactor during Autothermal Thermophilic Aerobic Digestion (ATAD) processing results in auto-heating, thermal treatment and total solids reduction, however, the ability to eliminate pathogenic organisms has not been analysed under large scale process conditions. We evaluated the ATAD process over a period of one year in a two stage, full scale Iri...

Using internal carbon source contained in waste activated sludge (WAS) is beneficial for nitrogen removal from wastewater with low carbon/nitrogen ratio, but it is usually limited by sludge disintegration. This study presented a novel strategy based on free nitrous acid (FNA) pretreatment to intensify the release of organic matters from WAS for enhanced denitrification. During FNA pretreatment,...

Additional enzymes pretreatment technology can promote the hydrolysis of excess activated sludge, while increasing gas production. Single enzyme pretreatment of sludge, alkaline protease has a better effect of hydrolysis. The optimum working conditions for alkaline protease: pH value of 8.0, the solid-liquid ratio of 1:4, the enzyme concentration of 2%, the working temperature of 55°C, reaction...

In the temperature range of 10 to 80 oC and in a batch digester, a typical activated sludge was digested aerobically. Reaction rate constants were determined by measuring the amounts of volatiles removed from the suspended solids at different time intervals during the process. The maximum value of the reaction rate constant (0.45 d ) occurred in the temperature range of 55-60 ̊C. Removal of indi...