Case studies in dynamic modelling of large-scale wastewater treatment plants

Dynamic mathematical modelling of full-scale wastewater treatment plants requires an optimal level of detail to be accurate, effective, but still manageable. Single process models tend to oversimplify the complexities of a large-scale plant and result in erroneous calibrated parameter values or limited predictive power for the model – on the other hand, modelling of every process and process unit is usually impractical, since it cannot be supported by reliable plant data, and requires prohibitive sampling costs and effort. Level of aggregation, settler dimensionality and reactivity, and plug-flow hydraulics were investigated with the help of a sophisticated dynamic modelling package. The results show that there is no general rule or global ‘optimal level’ of modelling – the required modelling detail is a function of influent flow and loading levels, and processes to be simulated (BOD removal, nitrification-denitrification, biological phosphorus removal, settling). In the case of real-life plants, supportable modelling level is often constrained by data availability and reliability.

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Bottlenecks in the Implementation of On-Site Wastewater Treatment Plants on a Large Scale in The Netherlands

Water Science & Technology ◽

10.2166/wst.1990.0214 ◽

1990 ◽

Vol 22 (3-4) ◽

pp. 291-298

Author(s):

Frits A. Fastenau ◽

Jaap H. J. M. van der Graaf ◽

Gerard Martijnse

Keyword(s):

Wastewater Treatment ◽

The Netherlands ◽

Large Scale ◽

Wastewater Treatment Plants ◽

Housing Stock ◽

Research Work ◽

Field Research ◽

Domestic Wastewater ◽

Research Programme ◽

Definition Of

More than 95 % of the total housing stock in the Netherlands is connected to central sewerage systems and in most cases the wastewater is treated biologically. As connection to central sewerage systems has reached its economic limits, interest in on-site treatment of the domestic wastewater of the remaining premises is increasing. A large scale research programme into on-site wastewater treatment up to population equivalents of 200 persons has therefore been initiated by the Dutch Ministry of Housing, Physical Planning and Environment. Intensive field-research work did establish that the technological features of most on-site biological treatment systems were satisfactory. A large scale implementation of these systems is however obstructed in different extents by problems of an organisational, financial and/or juridical nature and management difficulties. At present research is carried out to identify these bottlenecks and to analyse possible solutions. Some preliminary results are given which involve the following ‘bottlenecks':-legislation: absence of co-ordination and absence of a definition of ‘surface water';-absence of subsidies;-ownership: divisions in task-setting of Municipalities and Waterboards; divisions involved with cost-sharing;-inspection; operational control and maintenance; organisation of management;-discharge permits;-pollution levy;-sludge disposal. Final decisions and practical elaboration of policies towards on-site treatment will have to be formulated in a broad discussion with all the authorities and interest groups involved.

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The control of small and medium sized public wastewater treatment plants in the Veneto region (North Italy): general situation, critical issues and case studies

Water Practice & Technology ◽

10.2166/wpt.2017.082 ◽

2017 ◽

Vol 12 (4) ◽

pp. 761-779

Author(s):

M. Ostoich ◽

F. Serena ◽

A. Pozzobon ◽

L. Tomiato

Keyword(s):

Wastewater Treatment ◽

Case Studies ◽

Wastewater Treatment Plants ◽

Waste Water Treatment ◽

River Basin Management ◽

Critical Parameters ◽

Organic Load ◽

General Situation ◽

Veneto Region ◽

Critical Issues

Abstract Water bodies' quality objectives are defined in accordance with the Urban Wastewater Treatment Directive 91/271/EEC and the Water Framework Directive 2000/60/EC. For regulation and control of small-sized waste-water treatment plants (WWTPs), responsibility is delegated in Italy to Regional Authorities that fix specific regulations (Water Protection Plan WPP included in the River Basin Management Plan RBMP) in collaboration with the District Authorities. Small (<2,000 population equivalent – PE) and medium sized (2,000–10,000 PE) WWTPs in the Veneto Region (North Italy) represent about 10% of the total organic load (Imhoff systems included). This also comprises some industrial discharges. Due to the urban sprawl, plants are spread over the regional territory. In the Veneto Region, data from the official census reveals there are n. 248 plants under 2,000 PE and 135 plants in 2,000–10,000 range while the total number of authorized plants is 488 for a total potentiality of 9,141,572 PE. Data from institutional controls performed by the Veneto Regional Environmental Agency (ARPAV) on WWTPs has been recovered for all the WWTPs with up to 10,000 PE in the provinces of Venice, Treviso and Vicenza (for a total of 306,118 PE and for a total of 164 plants) in the period 2008–2015 and elaborated to assess critical parameters and plants. The general situation, critical issues and case studies have been presented and discussed. Organic load, nutrients and Escherichia coli are the most critical parameters considering the regional WPP.

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Choice of the efficient flow diagram of biological wastewater treatment at municipal wastewater treatment plants

Environmental Problems ◽

10.23939/ep2021.04.244 ◽

2021 ◽

Vol 6 (4) ◽

pp. 244-250

Author(s):

Serhii Protsenko ◽

◽

Mykola Kizyeyev ◽

Olha Novytska ◽

◽

...

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

High Efficiency ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Dynamic Modelling ◽

Flow Diagram ◽

Biological Wastewater Treatment ◽

Municipal Wastewater Treatment ◽

Residual Content

The possibility of increasing the efficiency of municipal wastewater treatment plant (WWTP) operation by changing the flow diagram of biological wastewater treatment in aeration tanks at minimum expenses for their reconstruction is shown in the paper on the example of one of the regional centres of Ukraine. The technology of nitri-denitrification of wastewater according to the flow diagram of the two-stage modified Ludzak-Ettinger process is offered for the considered conditions. The distribution of wastewater flows and internal nitrate recycling between the individual stages of this flow diagram has been optimized in order to minimize the residual content of total nitrogen in the treated effluents. Computer dynamic modelling of biochemical processes has proved the high efficiency and reliability of the flow diagram proposed by the authors.

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Odour emission capacity of wastewaters - standardization of measurement method and application

Water Science & Technology ◽

10.2166/wst.1998.0176 ◽

1998 ◽

Vol 38 (3) ◽

pp. 61-69 ◽

Cited By ~ 2

Author(s):

Franz-Bernd Frechen ◽

Wulf Köster

Keyword(s):

Wastewater Treatment ◽

Liquid Phase ◽

Case Studies ◽

Mass Flow ◽

Measurement Method ◽

Wastewater Treatment Plants ◽

Ambient Air ◽

New Method ◽

Sewer Systems ◽

Emission Capacity

Odorous emissions from sewer systems and wastewater treatment plants can cause serious annoyance in the vicinity. Odorants which are present in a liquid phase are emitted into ambient air at the liquid-gaseous interface. The amount and the variation of emitted mass flow of odorants is significantly influenced by the amount of odorants which are present in the liquid. Up to now, however, no measurement method was available to describe this parameter, which can be called “Odorants Emission Capacity”. The paper describes a standardized method of determining the “Odorants Emission Capacity” and shows results and consequences from several case studies where this new method was applied.

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Variations in dissolved inorganic carbon species in effluents from large-scale municipal wastewater treatment plants (Qingdao, China) and their potential impacts on coastal acidification

Environmental Science and Pollution Research ◽

10.1007/s11356-019-04871-2 ◽

2019 ◽

Vol 26 (15) ◽

pp. 15019-15027 ◽

Cited By ~ 2

Author(s):

Xiang-Yu Liu ◽

Xu-Feng Yang ◽

Yun-Xiao Li ◽

Han Zang ◽

Long-Jun Zhang

Keyword(s):

Wastewater Treatment ◽

Large Scale ◽

Municipal Wastewater ◽

Inorganic Carbon ◽

Wastewater Treatment Plants ◽

Dissolved Inorganic Carbon ◽

Municipal Wastewater Treatment ◽

Carbon Species ◽

Municipal Wastewater Treatment Plants ◽

Coastal Acidification

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Status and future trends of ICA in wastewater treatment – a European perspective

Water Science & Technology ◽

10.2166/wst.2002.0653 ◽

2002 ◽

Vol 45 (4-5) ◽

pp. 485-494 ◽

Cited By ~ 25

Author(s):

U. Jeppsson ◽

J. Alex ◽

M.N. Pons ◽

H. Spanjers ◽

P.A. Vanrolleghem

Keyword(s):

Wastewater Treatment ◽

Large Scale ◽

Driving Forces ◽

Wastewater Treatment Plants ◽

Future Trends ◽

Real Time Control ◽

Individual Country ◽

Time Control ◽

The Status ◽

On Line

The status of instrumentation, control and automation (ICA) within the European wastewater community is reviewed and some major incentives and bottlenecks are defined. Future trends of ICA are also discussed. The information is based on a COST 624 workshop and a non-exhaustive survey with regard to ICA carried out in 13 European countries during March 2001. The level of instrumentation (type of sensors, usage frequency, etc.) and how these instruments are used for on-line control purposes are presented for each individual country (Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Netherlands, Romania, Slovenia, Spain, Sweden and Switzerland). The most common types of applied real-time control in wastewater treatment plants are given. One conclusion of the paper is that sensors no longer represent the main bottleneck for on-line control, rather the lack of plant flexibility is more troublesome. Moreover, the current transitional phase of the wastewater industry in Europe represents a unique opportunity to apply ICA on a large scale. The driving forces are simply too strong to ignore.

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Modelling of full-scale wastewater treatment plants with different treatment processes using the Activated Sludge Model no. 3

Water Science & Technology ◽

10.2166/wst.2001.0012 ◽

2001 ◽

Vol 44 (1) ◽

pp. 49-56 ◽

Cited By ~ 7

Author(s):

M. Wichern ◽

F. Obenaus ◽

P. Wulf ◽

K.-H. Rosenwinkel

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Phosphorus Removal ◽

Large Scale ◽

Wastewater Treatment Plants ◽

Biological Phosphorus Removal ◽

Activated Sludge Model ◽

Treatment Processes ◽

Biological Phosphorus ◽

P Removal

In 1999 the Activated Sludge Model no. 3 (ASM 3) by the IWA task Group on Mathematical Modeling for Design and Operation of Biological Wastewater Treatment was presented. The model is used for simulation of nitrogen removal. On the basis of a new calibration of the ASM 3 with the easy degradable COD measured by respiration simulation runs of this paper have been done. In 2000 a biological phosphorus removal module by the EAWAG was added to the calibrated version of ASM 3 and is now serving the current requirements for modelling the enhanced biological P-removal. Only little experiences with different load situations of large-scale wastewater treatment plants were made with both new models so far. This article reports the experiences with the simulation and calibration of the biological parameters using ASM 3 and the EAWAG BioP Module. Three different large-scale wastewater treatment plants in Germany with different treatment systems will be discussed (Koblenz: pre-denitrification; Hildesheim: simultaneous denitrification with EBPR; Duderstadt: intermediate denitrification with EBPR). Informations regarding the choice of kinetic and stoichiometric parameters will be given.

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Mathematical modelling of small wastewater treatment plants: power and limitations

Water Science & Technology ◽

10.2166/wst.2005.0350 ◽

2005 ◽

Vol 51 (10) ◽

pp. 47-54

Author(s):

N. Philips ◽

S. Heyvaerts ◽

K. Lammens ◽

J.F. Van Impe

Keyword(s):

Wastewater Treatment ◽

Mathematical Modelling ◽

Large Scale ◽

Wastewater Treatment Plants ◽

Tracer Tests ◽

Model Structure ◽

Internal Flows ◽

Small Systems ◽

Treatment Processes ◽

Frequent Sampling

Although mathematical modelling of biological wastewater treatment processes has proved to be valuable for large-scale WWTPs (wastewater treatment plants) little experience has been acquired in the mathematical modelling of small wastewater treatment plants. This paper seeks to evaluate the applicability of mathematical modelling on small systems, which are characterized by high fluctuations in organic and hydraulic loads and little possibility for control. In order to achieve this, the paper examines the different steps in a general modelling protocol. One important bottleneck for the general use of mathematical modelling of small systems that emerges is the frequent sampling and many analyses needed for characterization of the flows while its applicability is limited. On the other hand, the determination of the model structure of a small WWTP can be quite valuable. Experiments show that tracer tests should include tests with a highly varying influent flow rate to spot independent small internal flows as these can have a significant impact on the behaviour of peak concentrations throughout the system. In addition, the model structure determination can provide useful information on dead zones, short-circuiting and mixing behaviour in the plant.

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