Usage of textile dyes BB41 and BR46 for microscopic examination of filamentous bacteria in activated sludge reactor: a new staining method

Abstract The existence of certain filamentous organisms may indicate one or more operation and control problems in activated sludge reactors. Microscopic evaluation of these filamentous organisms needs staining methods that can be achieved after some steps. This study is the first to show that textile dyes such as Astrazon Blue FGGL (BB41) and Astrazon Red FBL (BR46) can be used to identify filamentous organisms. Both dyes were used as a new, effective, and easy method for detecting the presence of filamentous bacteria. When contacted with BB41 and BR46, the filamentous bacteria and their characteristics were easily observed under the microscope. According to sources, textile dyes used in this study have not been used to diagnose filamentous bacteria before. According to the findings of this study, important morphological properties of filamentous bacteria were easily observed using BB41 and BR46. “Attached growth, branching, septa, and granules of various nutrients” were clearly seen by the stains (BB41 and BR46) with the help of this method. This method may allow the examiners to examine the specimens of filamentous bacteria in the activated sludge reactors. Detailed information has been presented in this paper.

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Novel feast-fast technique for filamentous foam control in the activated sludge process – introducing a new foam-measurement method

Water Science & Technology ◽

10.2166/wst.2000.0364 ◽

2000 ◽

Vol 42 (3-4) ◽

pp. 95-102 ◽

Cited By ~ 4

Author(s):

H. Chua ◽

W. Lo ◽

P.H. Yu ◽

S.N. Sin ◽

Y.G. Zhao ◽

...

Keyword(s):

Activated Sludge ◽

Measurement Method ◽

Prolonged Exposure ◽

Specific Growth ◽

Foam Stability ◽

Activated Sludge Process ◽

Filamentous Bacteria ◽

Treatment Efficiency ◽

Normal Range ◽

And Control

Overgrowth of filamentous Nocardia spp. in the activated sludge microbial ecosystem was previously identified as the cause of foaming problems in Hong Kong. In this work, the specific growth rate of N. amarae was found to be significantly higher than that of non-filamentous bacteria under food-to-microorganism (F/M) ratios lower than 0.5 mgBOD/mgMLSS-day, and was used as the basis for the development of a novel Feast-Fast Operation (FFO) for the prevention and control of foaming problems. The F/M ratio in the “feasting” aeration unit was 0.8 mgBOD/mgMLSS-day while that in the “fasting” aeration unit was 0.2 mgBOD/mgMLSS-day, resulting in an overall process F/M ratio that remained within the normal range, while avoided prolonged exposure of the sludge ecosystem to an F/M ratio below 0.5 mgBOD/mgMLSS-day. The FFO suppressed filamentous overgrowth and foaming without adversely affecting the organic treatment efficiency of the modified process. A new and convenient measurement method was developed for quantifying the degree of foaming and foam stability in activated sludge.

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System Identification and Control of the Activated Sludge Process by Use of a Statistical Model

Water Science & Technology ◽

10.2166/wst.1989.0316 ◽

1989 ◽

Vol 21 (10-11) ◽

pp. 1161-1172 ◽

Cited By ~ 8

Author(s):

M. Hiraoka ◽

K. Tsumura

Keyword(s):

Control System ◽

System Identification ◽

Statistical Model ◽

Activated Sludge ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Ar Model ◽

Diurnal Changes ◽

Activated Sludge Process ◽

And Control

The authors have been developing a hierarchical control system for the activated sludge process which consists of an upper level system controlling long-term seasonal variations, a control system of intermediate level aiming at optimization of the process and a control system of lower level controlling diurnal changes or hourly fluctuations. The control system using the multi-variable statistical model is one of the most appropriate control systems based on the modern control theory, for applying the lower level control of the activated sludge process. This paper introduces our efforts for developing the reliable data acquisition system, the control experiments applying the AR-model, one of the statistical models which were conducted at a pilot plant and present studies on the system identification and control at a field sewage treatment plant.

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Role of Glycogen as an Intracellular Carbon Reserve of Activated Sludge in the Competitive Growth of Filamentous and Non-Filamentous Bacteria

Water Science & Technology ◽

10.2166/wst.1991.0541 ◽

1991 ◽

Vol 23 (4-6) ◽

pp. 899-905 ◽

Cited By ~ 12

Author(s):

Y. Matsuzawa ◽

T. Mino

Keyword(s):

Activated Sludge ◽

Feeding Pattern ◽

Filamentous Bacteria ◽

Competitive Growth ◽

Maximum Capacity ◽

Intermittent Feeding ◽

Feeding Type ◽

Continuous Feeding ◽

The Relationship

Activated sludge mixed cultures were cultivated with a glucose containing substrate in order to investigate the relationship between the feeding pattern (continuous or intermittent feeding) and the glycogen reservation capacity of activated sludge. An experimental method to measure the maximum capacity of glycogen reservation in the sludge was developed. Sludge with higher glycogen reservation capacity has an ability to synthesize glycogen faster, which ensures the higher glucose uptake. Therefore, sludge which has high glycogen reservation capacity becomes predominant in intermittently fed reactors. When the feeding pattern was changed from continuous feeding to intermittent feeding, a filamentous bacterium, Type 1701, started to decrease and a gram positive tetrad coccus became predominant. When the feeding pattern was returned to continuous feeding, Type 1701 re-appeared. Type 1701 has lower glycogen reservation capacity than the tetrad coccus. Therefore, the former cannot dominate over the latter in intermittently fed reactors.

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Multivariable modeling and control of an activated sludge process

Water Science & Technology ◽

10.2166/wst.1998.0527 ◽

1998 ◽

Vol 37 (12) ◽

pp. 149-156 ◽

Cited By ~ 4

Author(s):

Carl-Fredrik Lindberg

Keyword(s):

Activated Sludge ◽

Nitrate Concentration ◽

State Space Model ◽

Activated Sludge Process ◽

Invariant State ◽

Linear Quadratic ◽

Modeling And Control ◽

Space Model ◽

And Control ◽

Time Invariant

This paper contains two contributions. First it is shown, in a simulation study using the IAWQ model, that a linear multivariable time-invariant state-space model can be used to predict the ammonium and nitrate concentration in the last aerated zone in a pre-denitrifying activated sludge process. Secondly, using the estimated linear model, a multivariable linear quadratic (LQ) controller is designed and used to control the ammonium and nitrate concentration.

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Deep learning-based morphology classification of activated sludge flocs in wastewater treatment plants

Environmental Science Water Research & Technology ◽

10.1039/d0ew00908c ◽

2021 ◽

Author(s):

Hisashi Satoh ◽

Yukari Kashimoto ◽

Naoki Takahashi ◽

Takashi Tsujimura

Keyword(s):

Wastewater Treatment ◽

Deep Learning ◽

Activated Sludge ◽

Morphological Change ◽

Wastewater Treatment Plants ◽

Filamentous Bacteria ◽

Sludge Flocs

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.

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Validation of a new image analysis procedure for quantifying filamentous bacteria in activated sludge

Water Science & Technology ◽

10.2166/wst.2014.296 ◽

2014 ◽

Vol 70 (6) ◽

pp. 955-963 ◽

Cited By ~ 4

Author(s):

Ewa Liwarska-Bizukojc ◽

Marcin Bizukojc ◽

Olga Andrzejczak

Keyword(s):

Image Processing ◽

Image Analysis ◽

Activated Sludge ◽

Analysis Procedure ◽

Automated Image Analysis ◽

Filamentous Bacteria ◽

Image Processing And Analysis ◽

Manual Counting ◽

Analysis Application ◽

Activated Sludge Systems

Quantification of filamentous bacteria in activated sludge systems can be made by manual counting under a microscope or by the application of various automated image analysis procedures. The latter has been significantly developed in the last two decades. In this work a new method based upon automated image analysis techniques was elaborated and presented. It consisted of three stages: (a) Neisser staining, (b) grabbing of microscopic images, and (c) digital image processing and analysis. This automated image analysis procedure possessed the features of novelty. It simultaneously delivered data about aggregates and filaments in an individual calculation routine, which is seldom met in the procedures described in the literature so far. What is more important, the macroprogram performing image processing and calculation of morphological parameters was written in the same software which was used for grabbing of images. Previously published procedures required using two different types of software, one for image grabbing and another one for image processing and analysis. Application of this new procedure for the quantification of filamentous bacteria in the full-scale as well as laboratory activated sludge systems proved that it was simple, fast and delivered reliable results.

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Nitrogen Removal from Wastewater by Activated Sludge Reactor with a Carbon-Felt Medium.

Doboku Gakkai Ronbunshu ◽

10.2208/jscej.2001.685_115 ◽

2001 ◽

pp. 115-122

Author(s):

Tsuneo TANAKA ◽

Masuo OZAKI ◽

Masao KURODA

Keyword(s):

Activated Sludge ◽

Nitrogen Removal ◽

Carbon Felt ◽

Activated Sludge Reactor

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Systematic Multimodeling Methodology Applied to an Activated Sludge Reactor Model

Industrial & Engineering Chemistry Research ◽

10.1021/ie8017687 ◽

2010 ◽

Vol 49 (6) ◽

pp. 2790-2799 ◽

Cited By ~ 40

Author(s):

Anca Maria Nagy ◽

Gilles Mourot ◽

Benoît Marx ◽

José Ragot ◽

Georges Schutz

Keyword(s):

Activated Sludge ◽

Reactor Model ◽

Activated Sludge Reactor

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Biosolids odor reduction by solids inventory management in the secondary activated sludge treatment system

Water Science & Technology ◽

10.2166/wst.2009.852 ◽

2009 ◽

Vol 59 (2) ◽

pp. 241-247 ◽

Cited By ~ 2

Author(s):

K. Sekyiamah ◽

H. Kim

Keyword(s):

Activated Sludge ◽

Inventory Management ◽

Process Parameters ◽

Treatment Plant ◽

Treatment System ◽

Sludge Treatment ◽

System A ◽

Treatment Processes ◽

Dominant Process ◽

And Control

A wastewater treatment plant consists of unit processes designed to achieve specific waste reduction goals. Offensive odors associated with these treatment processes are a constant source of public complaints. The purpose of this study was to statistically determine the process parameters that influence the formation of volatile sulfur compounds (VSCs) in the secondary treatment system. A statistical model was developed to relate the process parameters to the formation of VSCs in this system. The model established that F/M ratio, sludge blanket depth and SSV60 were the dominant process parameters that influenced the formation of VSCs in the secondary sedimentation basin. This model provides a useful tool for plant engineers to predict and control the VSC formation in a secondary activated sludge treatment system.

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