scholarly journals Microbial Communities and Nitrogen-Utilizing Bacteria of Rotating Biological Contactors and Activated Sludge Treating Public Sewage and Night Soil/Johkasou Sludge

2021 ◽  
Vol 19 (3) ◽  
pp. 109-119
Author(s):  
Tsukasa Ito ◽  
Yu Yamanashi ◽  
Naoki Noguchi ◽  
Naoki Miyazato ◽  
Toru Aoi
Keyword(s):  
Activated Sludge ◽  
Microbial Communities ◽  
Rotating Biological Contactors

Performance Stability of Small Biological Chemical Treatment Plants

1990 ◽  
Vol 22 (3-4) ◽  
pp. 275-282
Author(s):  
R. Storhaug
Keyword(s):  
Activated Sludge ◽  
Chemical Treatment ◽  
Chemical Precipitation ◽  
Poor Quality ◽  
Precipitation Process ◽  
Chemical Plants ◽  
Effluent Standards ◽  
Main Portion ◽  
Rotating Biological Contactors ◽  
Number Of Treatment

Biological and chemical treatment plants constitute a main portion of the overall number of treatment plants in Norway. The biological and chemical plants are divided into three process groups, simultaneous precipitation and activated sludge, combined precipitation and rotating biological contactors (RBC) and post precipitation and activated sludge. Aluminium sulphate or ferric chloride are the commonly used flocculants in the chemical precipitation process. Effluent data from 174 Norwegian biological chemical treatment plants are evaluated. Compared to the effluent standards for each process group, post precipitation shows the best performance. On an average these plants have the lowest actual utilization of the design capacity. The most important factors that cause the treatment plants not to meet the effluent standards are, poor quality of the sewer system, improper design of the plant and organizational problems. Satisfactory separation of particles, flow equalization and proper operational management, are the basic demands to achieve low effluent concentrations for tot-P and BOD7.

scholarly journals Time-series genome-centric analysis unveils bacterial response to operational disturbance in activated sludge

2019 ◽  
Author(s):  
María Victoria Pérez ◽  
Leandro D. Guerrero ◽  
Esteban Orellana ◽  
Eva L. Figuerola ◽  
Leonardo Erijman
Keyword(s):  
Growth Rate ◽  
Time Series ◽  
Wastewater Treatment ◽  
Activated Sludge ◽  
Microbial Communities ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Operating Conditions ◽  
The Face

ABSTRACTUnderstanding ecosystem response to disturbances and identifying the most critical traits for the maintenance of ecosystem functioning are important goals for microbial community ecology. In this study, we used 16S rRNA amplicon sequencing and metagenomics to investigate the assembly of bacterial populations in a full-scale municipal activated sludge wastewater treatment plant over a period of three years, including a period of nine month of disturbance, characterized by short-term plant shutdowns. Following the reconstruction of 173 metagenome-assembled genomes, we assessed the functional potential, the number of rRNA gene operons and thein situgrowth rate of microorganisms present throughout the time series. Operational disturbances caused a significant decrease in bacteria with a single copy of the ribosomal RNA (rrn) operon. Despite only moderate differences in resource availability, replication rates were distributed uniformly throughout time, with no differences between disturbed and stable periods. We suggest that the length of the growth lag phase, rather than the growth rate, as the primary driver of selection under disturbed conditions. Thus, the system could maintain its function in the face of disturbance by recruiting bacteria with the capacity to rapidly resume growth under unsteady operating conditions.IMPORTANCEIn this work we investigated the response of microbial communities to disturbances in a full-scale activated sludge wastewater treatment plant over a time-scale that included periods of stability and disturbance. We performed a genome-wide analysis, which allowed us the direct estimation of specific cellular traits, including the rRNA operon copy number and the in situ growth rate of bacteria. This work builds upon recent efforts to incorporate growth efficiency for the understanding of the physiological and ecological processes shaping microbial communities in nature. We found evidence that would suggest that activated sludge could maintain its function in the face of disturbance by recruiting bacteria with the capacity to rapidly resume growth under unsteady operating conditions. This paper provides relevant insights into wastewater treatment process, and may also reveal a key role for growth traits in the adaptive response of bacteria to unsteady environmental conditions.

Diversity and assembly patterns of activated sludge microbial communities: A review

2018 ◽  
Vol 36 (4) ◽  
pp. 1038-1047 ◽  
Author(s):  
Yu Xia ◽  
Xianghua Wen ◽  
Bing Zhang ◽  
Yunfeng Yang
Keyword(s):  
Activated Sludge ◽  
Microbial Communities

scholarly journals High temperature utilization of PAM and HPAM by microbial communities enriched from oilfield produced water and activated sludge

AMB Express ◽  
2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Carolina Berdugo-Clavijo ◽  
Arindom Sen ◽  
Mojtaba Seyyedi ◽  
Harvey Quintero ◽  
Bill O’Neil ◽  
...  
Keyword(s):  
High Temperature ◽  
Activated Sludge ◽  
Microbial Communities ◽  
Produced Water ◽  
Oilfield Produced Water

Evolution of microbial communities in the activated sludge process

1983 ◽  
Vol 17 (10) ◽  
pp. 1275-1279 ◽  
Author(s):  
Felix Kucnerowicz ◽  
Willy Verstraete
Keyword(s):  
Activated Sludge ◽  
Microbial Communities ◽  
Activated Sludge Process

Microbial population dynamics in laboratory-scale activated sludge reactors

2002 ◽  
Vol 46 (1-2) ◽  
pp. 19-27 ◽  
Author(s):  
K. Kaewpipat ◽  
C.P.L. Grady
Keyword(s):  
Activated Sludge ◽  
Microbial Communities ◽  
System Performance ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Treatment Plant ◽  
Laboratory Scale ◽  
Rrna Gene ◽  
Significant Finding ◽  
Prokaryotic Community ◽  
Activated Sludge Systems

As a first step in understanding nonlinear dynamics in activated sludge systems, two laboratory-scale sequencing batch reactors were operated under identical conditions and changes in their microbial communities were followed through microscopic examination, macroscopic observation, and denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rRNA gene segments from the prokaryotic community. Two experiments were performed. The first used activated sludge from a local wastewater treatment plant to start the replicate reactors. The second used the biomass from the first experiment as a source by intermixing the two and equally redistributing the biomass into the two replicate reactors. For both experiments, the two reactors behaved fairly similarly and had similar microbial communities for a period of 60 days following start-up. Beyond that, the microbial communities in the two reactors in the first experiment diverged in composition, while those in the second experiment remained fairly similar. This suggests that the degree of change occurring in replicate reactors depends upon the severity of perturbation to which they are exposed. The DGGE data showed that the bacterial communities in both experiments were highly dynamic, even though the system performance of the replicate reactors were very similar, suggesting that dynamics within the prokaryotic community is not necessarily reflected in system performance. Moreover, a significant finding from this study is that replicate activated sludge systems are not identical, although they can be very similar if started appropriately.

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