A framework for the design of the future energy-efficient, cost-effective, reliable, resilient, and sustainable full-scale wastewater treatment plants

New acts on wastewater disposal demand for higher process stability and effluent quality. The A-B process, a novel two step treatment system, meets these requirements in a cost effective way. Five full-scale plants have been put in operation over the last two years. The objective of this paper is to give an outline of the features of the A-B system in the context of the results of these full-scale plants. In spite of the extreme high load, the A-stage can be operated at a high reduction rate and is stable. Variations in the organic load and pH- and toxic shocks are leveled out and a constant, mainly soluble effluent is supplied. This implicates a low sludge production in the B-stage. As a consequence higher overall reduction rates are obtained as compared to conventional processes at the same sludge load. Very low and stable final effluent concentrations are observed in all full-scale plants. Of special interest are the possibilities of upgrading existing conventional treatment facilities, at minor costs, by incorporating the A-B technology. The A-B process therefore can be considered as a very promising, cost effective alternative for both existing and new wastewater treatment plants in responding to the increasing effluent demands.

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Reconsideration and upgrading of sampling and analysis methods for avoiding measurement-related design and operation failures in wastewater treatment

Water SA ◽

10.17159/wsa/2019.v45.i3.6729 ◽

2019 ◽

Vol 45 (3 July) ◽

Author(s):

V Bakos ◽

A Deák ◽

A Jobbágy

Keyword(s):

Wastewater Treatment ◽

Input Data ◽

Wastewater Treatment Plants ◽

Comparative Method ◽

Cost Effective ◽

Electrochemical Measurement ◽

Full Scale ◽

Floc Structure ◽

Wastewater Quality

Success of design and high operational efficiency may basically stand or fall on the quality of measured (or estimated) input data. Even small mistakes committed in the initial steps of sampling and analysis may become large once scaled up in the design process or during full-scale operation. The paper provides several experiment-based practical recommendations and easily implemented, powerful methods for appropriate sampling and analysis practice in wastewater treatment. Representative wastewater characterization is crucial for satisfactory design and cost-effective operation. The paper highlights hidden problems and challenges of sampling and analysis in activated sludge wastewater treatment which may strongly affect the quality of input data, and thus basically determine the modelling outputs. Full-scale results proved that wastewater quality may change significantly in the sampling tubing and vessels; during the sampling process even nitrification can happen. Regarding sludge settling measurements, effects of dilution, temperature, floc structure, nitrate and dissolved oxygen concentrations as well as current biochemical condition of the sludge sample have been studied and important recommendations provided. A combined comparative method including SVI and DSVI measurements has been elaborated for indication and early warning alert of undesired floc structure transformations. Influent BOD5 concentration is a key factor for describing biodegradability and denitrification capacity of wastewater to be treated. Results of the two most commonly used BOD testing methods were compared for preclarified wastewater. An electrochemical measurement technique provided significantly lower BOD5 concentrations compared to manometric analysis results with a difference of 23% and 15% on average for unfiltered and filtered samples, respectively. Effects of BOD-based fractionation deviations on predictable denitrification efficiency were studied at different inlet C/N ratios by simulating existing full-scale wastewater treatment plants resulting in remarkable differences in effluent nitrate concentrations. Based on the results, application of the manometric BOD measurement method proved to be preferable.

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Estimating costs and benefits of advanced control for wastewater treatment plants – the MAgIC methodology

Water Science & Technology ◽

10.2166/wst.2006.126 ◽

2006 ◽

Vol 53 (4-5) ◽

pp. 215-223 ◽

Cited By ~ 17

Author(s):

M. Devisscher ◽

G. Ciacci ◽

L. Fé ◽

L. Benedetti ◽

D. Bixio ◽

...

Keyword(s):

Wastewater Treatment ◽

Preliminary Analysis ◽

Wastewater Treatment Plants ◽

Cost Effective ◽

Full Scale ◽

Control Algorithms ◽

Costs And Benefits ◽

Advanced Control ◽

On Line

This paper discusses a methodology to estimate the costs and benefits of advanced control for wastewater treatment plants. The methodology has been applied to four wastewater treatment plants, representing four standard types of plants built in Flanders, Belgium. The paper outlines the methodology and illustrated results from one of the four design cases. General results are shown and contrasted with full-scale experience. The methodology appears to give realistic results and will be used for further refinement of default control algorithms for certain types of plants. A preliminary analysis indicates that on-line control can become cost-effective for plant sizes above 50,000 population equivalents.

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Design and construction of aeration systems for optimum operation of large wastewater treatment plants

Water Science & Technology ◽

10.2166/wst.1996.0333 ◽

1996 ◽

Vol 33 (12) ◽

pp. 189-198 ◽

Cited By ~ 4

Author(s):

Franz Bischof ◽

Marcus Höfken ◽

Franz Durst

Keyword(s):

Wastewater Treatment ◽

Energy Efficient ◽

Wastewater Treatment Plants ◽

Sewage Treatment ◽

Treatment Plant ◽

Cost Effective ◽

Optimum Process ◽

Total Energy Consumption ◽

Operational Costs ◽

Proper Design

The construction and operation of large wastewater treatment plants are very important tasks today. Choosing the optimum process design can help to keep initial costs low. Careful operation and modern equipment reduces the operational costs. Taking into account the huge demand (Anonymous EEC-Report 1990) for new wastewater treatment plants or plants which need to be upgraded after the new EEC legislation concerning sewage treatment came into force in May, 1991 (Anonymous EEC-Guideline 1991) it is quite clear that only cost-effective processes supported by energy-efficient equipment are the answer to economical wastewater treatment. Regarding the operational costs for biological treatment, approximately 70% of the total energy consumption is used for the activated sludge part of the treatment plant, i.e. for the stirring and aeration systems (Höfken et al. 1992). That shows how important the proper design of such systems is and implies that only innovative and energy-efficient equipment should be used. This paper presents theoretical considerations for the design of aeration systems for aerobic processes. These considerations lead to recommendations for the construction and the operation of aeration systems.

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Automatic buffer capacity based sensor for effluent quality monitoring

Water Science & Technology ◽

10.2166/wst.1996.0008 ◽

1996 ◽

Vol 33 (1) ◽

pp. 81-87

Author(s):

L. Van Vooren ◽

P. Willems ◽

J. P. Ottoy ◽

G. C. Vansteenkiste ◽

W. Verstraete

Keyword(s):

Wastewater Treatment ◽

Buffer Capacity ◽

Wastewater Treatment Plants ◽

Data Interpretation ◽

Full Scale ◽

Quality Monitoring ◽

Effluent Quality ◽

Capacity Curves ◽

On Line

The use of an automatic on-line titration unit for monitoring the effluent quality of wastewater plants is presented. Buffer capacity curves of different effluent types were studied and validation results are presented for both domestic and industrial full-scale wastewater treatment plants. Ammonium and ortho-phosphate monitoring of the effluent were established by using a simple titration device, connected to a data-interpretation unit. The use of this sensor as the activator of an effluent quality proportional sampler is discussed.

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