scholarly journals Use of DAIME for characterisation of activated sludge flocs

2017 ◽  
Vol 43 (4) ◽  
pp. 66-71 ◽  
Author(s):  
Anna Gnida

AbstractMonitoring of activated sludge flocs may provide important information for effective operation and control of wastewater treatment. The research objective is to demonstrate methodology for activated sludge image processing aimed to describe morphological characteristics of activated sludge flocs. The proposed software- -based method was presented and verified by analysis of several activated sludge samples. The results show high efficiency of image segmentation and floc recognition of more than 94% floc components. The analysis of a series of 50 pictures gives rapid and reliable results and can be performed in an automatic or semiautomatic mode. Given inherent heterogeneity of activated sludge flocs, multiple and repeated sample images capture (processing of 50 pictures at a time, repeated at least 4 times ) is recommended.

Author(s):  
Hisashi Satoh ◽  
Yukari Kashimoto ◽  
Naoki Takahashi ◽  
Takashi Tsujimura

A deep learning-based two-label classifier 1 recognized a 20% morphological change in the activated flocs. Classifier-2 quantitatively recognized an abundance of filamentous bacteria in activated flocs.


Membranes ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 231
Author(s):  
Yi Ding ◽  
Zhansheng Guo ◽  
Zhenlin Liang ◽  
Xuguang Hou ◽  
Zhipeng Li ◽  
...  

In this study, the characteristics of activated sludge flocs were investigated and their effects on the evolution of membrane fouling were considered in the anaerobic membrane bioreactors (AnMBR), which were operated at 25 and 35 °C for municipal wastewater treatment. It was found that the membrane fouling rate of the AnMBR at 25 °C was more severe than that at 35 °C. The membrane fouling trends were not consistent with the change in the concentration of soluble microbial product (SMP). The larger amount of SMP in the AnMBR at 35 °C did not induce more severe membrane fouling than that in the AnMBR at 25 °C. However, the polysaccharide and protein concentration of extracellular polymeric substance (EPS) was higher in the AnMBR at 25 °C in comparison with that in the AnMBR at 35 °C, and the protein/polysaccharide ratio of the EPS in the AnMBR at 25 °C was higher in contrast to that in the AnMBR at 35 °C. Meanwhile, the fouling tendencies measured for the AnMBRs could be related to the characteristics of loosely bound EPS and tightly bound EPS. The analysis of the activated sludge flocs characteristics indicated that a smaller sludge particle size and more fine flocs were observed at the AnMBR with 25 °C. Therefore, the membrane fouling potential in the AnMBR could be explained by the characteristics of activated sludge flocs.


Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2958
Author(s):  
Yi Ding ◽  
Zhansheng Guo ◽  
Xuguang Hou ◽  
Junxue Mei ◽  
Zhenlin Liang ◽  
...  

The anaerobic membrane bioreactors (AnMBR) were operated at 35 °C (H-AnMBR) and 25 °C (L-AnMBR) for long-term wastewater treatment. Two aerobic forward osmosis membrane bioreactors (FOMBRs) were utilized to treat the effluents of H-AnMBR and L-AnMBR, respectively. During the 180 days of operation, it is worth noting that the combined system was feasible, and the pollutant removal efficiency was higher. Though the permeate chemical oxygen demand (COD) of H-AnMBR (18.94 mg/L) was obviously lower than that of L-AnMBR (51.09 mg/L), the permeate CODs of the FOMBRs were almost the same with the average concentrations of 7.57 and 7.58 mg/L for the H-FOMBR and L-FOMBR, respectively. It was interesting that for both the AnMBRs, the permeate total nitrogen (TN) concentration was higher than that in bulk phase. However, the TN concentrations in the effluent remained stable with the values of 20.12 and 15.22 mg/L in the H-FOMBR and L-FOMBR effluents, respectively. For the two systems, the characteristics of activated sludge flocs were different for H-AnMBR-FOMBR sludge and L-AnMBR-FOMBR sludge. The viscosity of L-AnMBR-activated sludge (2.09 Pa·s) was higher compared to that of H-AnMBR (1.31 Pa·s), while the viscosity of activated sludge in L-FOMBR (1.44 Pa·s) was a little lower than that in H-FOMBR (1.48 Pa·s). The capillary water absorption time of L-AnMBR-activated sludge (69.6 s) was higher compared to that of H-AnMBR (49.5 s), while the capillary water absorption time of activated sludge in L-FOMBR (14.6 s) was little lower than that in H-FOMBR (15.6 s). The particle size of H-AnMBR-activated sludge (119.62 nm) was larger than that of L-AnMBR-activated sludge (84.92 nm), but the particle size of H-FOMBR-activated sludge (143.81 nm) was significantly smaller than that of L-FOMBR-activated sludge (293.38 nm). The observations of flocs indicated that the flocs of activated sludge in H-AnMBR were relatively loose, while the flocs of L-AnMBR were relatively tight. The fine sludge floc was less present in the L-FOMBR than in the H-FOMBR. Therefore, in the process of sewage treatment, the influent of each unit in the AnMBR-FOMBR system should have suitable organic content to maintain the particle sizes of sludge flocs.


Processes ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 2054
Author(s):  
Dan Selișteanu ◽  
Ion-Marian Popescu ◽  
Monica Roman ◽  
Constantin Șulea-Iorgulescu ◽  
Sorin Mehedințeanu

The design and implementation of a simulator, as a real-time application, for a complex process from the biological treatment stage of a wastewater treatment plant (WWTP), is addressed. More precisely, this emulator was achieved as a software tool that can be later integrated into a more complex SCADA (supervisory control and data acquisition) system of the WWTP Făcăi, Romania. The basic idea is to implement and validate a reduced-order model of the activated sludge process (ASP), initially simulated in the Matlab/Simulink environment (The MathWorks, Inc., Natick, MA, USA). Moreover, an advanced multivariable adaptive control scheme of the ASP is addressed. This software tool can be made to work in parallel with the evolution of the process and can have as input signals measured directly at the process level, possibly following parametric or model adaptations. The software emulator is developed in the LabWindows/CVI programming environment (National Instruments), which offers low-level access to hardware or software systems that have minimal open-architecture facilities. This environment provides versatile drivers and software packages that can facilitate the interaction with software tools developed within some earlier SCADA systems. The structure and the graphical interface of the emulator, some functionalities, experiments, and evolution of main variables are presented.


AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jing Lu ◽  
Yiguo Hong ◽  
Ying Wei ◽  
Ji-Dong Gu ◽  
Jiapeng Wu ◽  
...  

AbstractAnaerobic ammonium oxidation (anammox) process has been acknowledged as an environmentally friendly and time-saving technique capable of achieving efficient nitrogen removal. However, the community of nitrification process in anammox-inoculated wastewater treatment plants (WWTPs) has not been elucidated. In this study, ammonia oxidation (AO) and nitrite oxidation (NO) rates were analyzed with the incubation of activated sludge from Xinfeng WWTPs (Taiwan, China), and the community composition of nitrification communities were investigated by high-throughput sequencing. Results showed that both AO and NO had strong activity in the activated sludge. The average rates of AO and NO in sample A were 6.51 µmol L−1 h−1 and 6.52 µmol L−1 h−1, respectively, while the rates in sample B were 14.48 µmol L−1 h−1 and 14.59 µmol L−1 h−1, respectively. The abundance of the nitrite-oxidizing bacteria (NOB) Nitrospira was 0.89–4.95 × 1011 copies/g in both samples A and B, the abundance of ammonia-oxidizing bacteria (AOB) was 1.01–9.74 × 109 copies/g. In contrast, the abundance of ammonia-oxidizing archaea (AOA) was much lower than AOB, only with 1.28–1.53 × 105 copies/g in samples A and B. The AOA community was dominated by Nitrosotenuis, Nitrosocosmicus, and Nitrososphaera, while the AOB community mainly consisted of Nitrosomonas and Nitrosococcus. The dominant species of Nitrospira were Candidatus Nitrospira defluvii, Candidatus Nitrospira Ecomare2 and Nitrospira inopinata. In summary, the strong nitrification activity was mainly catalyzed by AOB and Nitrospira, maintaining high efficiency in nitrogen removal in the anammox-inoculated WWTPs by providing the substrates required for denitrification and anammox processes.


2020 ◽  
Vol 12 (9) ◽  
pp. 1461
Author(s):  
Jorge Sancho Martínez ◽  
Yadira Bajón Fernández ◽  
Paul Leinster ◽  
Mónica Rivas Casado

Wastewater treatment plants are essential for preserving the water quality of freshwater and marine ecosystems. It is estimated that, in the UK, as much as 11 billion liters of wastewater are treated on a daily basis. Effective and efficient treatment of wastewater requires treatment plants to be maintained in good condition. Recent studies have highlighted the potential of unmanned aircraft systems (UASs) and image processing to be used in autonomous and automated monitoring systems. However, the combined use of UASs and image processing for wastewater treatment plant inspections has not yet been tested. This paper presents a novel image processing-UAS framework for the identification of failures in trickling filters and activated sludge facilities. The results show that the proposed framework has an accuracy of 95% in the detection of failures in activated sludge assets, with the accuracy ranging between 55% and 81% for trickling filters. These results are promising and they highlight the potential use of the technology for the inspection of wastewater treatment plants.


1997 ◽  
Vol 36 (1) ◽  
pp. 21-30 ◽  
Author(s):  
Tanja Gschlößl ◽  
Ingrid Michel ◽  
Marion Heiter ◽  
Christian Nerger ◽  
Verena Rehbein

In biological wastewater treatment inorganic and organic substances are fixed and metabolized by mixed populations of microorganisms forming either activated sludge flocs or biofilms. Not only the type of wastewater but also the operational conditions promote the development of an adapted biocenosis of microorganisms with specialized enzymatic functions. Understanding the biological properties of the microorganisms, it is possible to assess the prevailing conditions in their natural environment. Regular microscopic and enzymatic investigations of activated sludge and biofilms thus improve the assessment of the stability of the processes and support troubleshooting in wastewater treatment plants. While the role of bacteria is often discussed, the importance of ciliated protozoes and metazoes for the maintenance of the stability of biofilm systems is rarely mentioned. In this paper we intend to show some new results of direct microscopic observations in different sorts of biofilm systems focussing upon ciliated protozoes and metazoes. Practical results will demonstrate the relation between enzymatic analysis, microscopic investigations and performance of biofilm systems.


2006 ◽  
Vol 5 (6) ◽  
pp. 1407-1413
Author(s):  
Ileana Ghita ◽  
Elisabeta Pena-Leonte ◽  
Aurelia Ballo ◽  
Cristiana Cosma ◽  
Ciprian Dumitrescu ◽  
...  

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