Extracellular polymeric substances (EPS) play important roles in regulating the dewaterability of sludge. This study sought to elucidate the influence of EPS on the dewaterability of sludge during bioleaching process. Results showed that, in bioleaching system with the co-inoculation of Acidithiobacillus thiooxidans TS6 and Acidithiobacillus ferrooxidans LX5 (A. t+A. f system), the capillary su...

A xylanase gene (xynG1-1) from Paenibacillus campinasensis G1-1 was expressed in Bacillus megaterium MS941 and a high level of extracellular xylansae activity (304.26 IU/mL) was achieved after induction with 0.5% xylose. The purified recombinant xylanase (XynG1-1R) revealed optimal activity at 60°C and pH 7.0 and retained 79% and 81% activity after incubation without substrate at 60°C, pH 5.0 a...

Sewage sludge is used as fertiliser and contains nutrients required for plant growth. It also contaminants that can leach into crops. The effects of sewage on kale plants were investigated. Mixture ratios 50:50 20:80 soil prepared. soil-sludge blends analysed selected metal residues. Kale seedlings 10-13 cm planted the different combinations. Leaf lengths measured 21 days post transplanting fou...

An increasing amount of sewage sludge requires reasonable management, whereas its storage might be environmentally hazardous. Due to the organic matter and nutrient presence in sediments, it may be used as organic fertilizer. However, beyond the valuable contests, sewage sludge can also contain toxic or dangerous ingredients like heavy metals. Therefore, there is a need to develop methods for r...

Stem diameter growth of g-year-old sweetgum (Liquidambar styraciflua) trees was measured and related with the activity of sucrose-synthase (SS), an enzyme that has been associated with carbon sink strength in agriculture crops and tree seedlings. In 1984, 1-O sweetgum seedlings were transplanted to control plots and plots amended with sewage sludge or nitrogen and phosphorus fertilizer. After 8...

BACKGROUND Biliary sludge is associated with gallbladder (GB) dysmotility and mucus hypersecretion suggesting a link between biliary sludge and the formation of GB mucoceles (GBM). If biliary sludge progresses to GBM, treatment to reduce the production and progression of sludge is warranted. HYPOTHESIS/OBJECTIVES The objective of this study was to determine the course of biliary sludge in dog...

This study evaluates the application of an anoxic side-stream reactor in the sludge return line of a conventional activated sludge system for the reduction of biomass production. The oxidation-reduction potential was maintained at -150 mV while the applied sludge loading rate was modified by changing the percentage of return sludge treated in this reactor. The observed yield from the convention...

A 2-year sampling campaign was conducted in three wastewater treatment plants of various sizes in the Rome area to assess the occurrence of nutrients and micropollutants among primary, secondary and digested sludge. The primary purpose was to evaluate the quality of different sludge types and their suitability for agricultural use. Primary sludge was consistently more polluted than secondary in...

Activated sludges are an inoculum source commonly used in biodegradation studies, as wastewater treatment facilities constitute an entry point to the environment for many chemicals. In this paper, the main issues relating to the use of activated sludge in biodegradability tests are presented. Special attention is also devoted to discussing the factors affecting both the activity of the microbia...

The effect of raw and anaerobically digested sludge on heat inactivation of poliovirus was investigated. Raw sludge was found to be very protective of poliovirus plaque-forming ability at all temperatures studied, but digested sludge had variable effects that were highly dependent upon the experimental conditions. In low concentrations and at relatively low inactivation temperatures, digested s...