The aim of this paper was to determine the effect of two different membrane bioreactor (MBR) configurations (external/immersed) on sludge structure and microbial activity. Sludge structure was deduced from rheological measurements. The high shear stress induced by the recirculation pump in the external MBR was shown to result in decreasing viscosity due to activated sludge (AS) deflocculation. Besides, soluble microbial products (SMP) release was higher in the external MBR (5 mgCOD gMLVSS(-1)) than in the immersed configuration (2 mgCOD gMLVSS(-1)). Microbial activity was followed from respirometry tests by focusing on the distinction between heterotrophs and autotrophs. An easier autotrophic microbe development was then observed in the immersed MBR compared to the external one. However, the external MBR was shown to allow better heterotrophic microbe development.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.biortech.2010.09.058 | DOI Listing |
Water Sci Technol
January 2025
China Construction Fifth Engineering Division Co., Ltd, Changsha, Hunan 410004, China.
Road runoff underwent treatment using a filter filled with sludge from drinking water treatment plants to assess its capacity for removing dissolved organic matter (DOM). This evaluation utilized resin fractionation, gel permeation chromatography, three-dimensional excitation-emission matrix fluorescence spectroscopy, and UV-Visible spectroscopy. The filter demonstrated enhanced efficiency in removing dissolved organic carbon, achieving removal rates between 70 and 80%.
View Article and Find Full Text PDFJ Water Health
January 2025
Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto University Katsura, Nishikyo, Kyoto 615-8540, Japan.
The discharge of sewage effluent is a major source of microbial contamination in drinking water sources, necessitating a comprehensive investigation of its impact on pathogenic bacterial communities. This study utilized full-length 16S rRNA gene amplicon sequencing to identify putative pathogenic bacteria and analyze their community structures in drinking water sources subjected to different levels of fecal pollution: urban rivers with low, moderate, and high sewage effluent mixing ratios, and mountain streams with minimal human impact. The sewage effluent itself was also analyzed.
View Article and Find Full Text PDFBioresour Technol
January 2025
College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China. Electronic address:
Thermophilic bacteria (TB) pretreatment is an efficient and environmentally friendly way for accelerating sludge hydrolysis. In this study, a complete comparison of the hydrolysis performance of Bacillus sp. AT07-1 (X1), Parageobacillus toebii X2 (X2), Geobacillus kaustophilus X3 (X3) and Parageobacillus toebii R-35642 (X4) was performed.
View Article and Find Full Text PDFEnviron Res
January 2025
School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha 410114, China; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha, 410004, China. Electronic address:
In the single-stage partial nitritation-anammox process for high-ammonium wastewater treatment, the presence of sufficient biomass with high activity is essential. This study developed an innovative airlift inner-circulation partition bioreactor (AIPBR) with a dual-cylinder structure. During the 362 days' operation, the AIPBR exhibited robust and stable nitrogen removal performance under diverse influent ammonium spanning from 300 to 1800 mg N/L.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Engineering Department, University of Palermo, Viale delle Scienze, Ed. 8, 90128, Palermo, Italy.
The products of an advanced sewage sludge fermentation process can be used to generate polyhydroxyalkanoates (PHAs), precursors of bioplastics considered excellent candidates for replacing petroleum-derived plastics. The aerobic feast-anoxic famine cycling strategy has proven to be an efficient method for enriching sewage sludge microbiota with PHA-producing microorganisms. This work evaluated the effect of different carbon to nitrogen ratios (C/N) of 3.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!