Stormnet: a connectionist model for dynamic management of wastewater treatment plants during storm events

1996 ◽  
Vol 33 (1) ◽  
pp. 247-256
Author(s):  
N. Gong ◽  
X. Ding ◽  
T. Denoeux ◽  
J.-L. Bertrand-Krajewski ◽  
M. Clément
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Real Data ◽  
Accurate Information ◽  
Connectionist Model ◽  
Storm Events ◽  
Deterministic Models ◽  
Receiving Waters ◽  
Solid Transport

Models for solid transport in sewers during storm events are increasingly used. An important application of these models is the management of treatment plants during storm events so as to improve the quality of receiving waters. However, a major difficulty that prevents more general use of these tools is their calibration, which requires field data, accurate information about catchments and sewers, and a specific methodology. For that reason, a connectionist model called STORMNET has been designed to reproduce and replace usual conceptual and deterministic models. This model requires fewer data, can be automatically calibrated, and is comparatively simple. It is composed of two recurrent neural networks for the simulation of hydrographs and pollutographs of suspended solids, respectively. In this paper, we present an updated version of STORMNET designed for optimal management of wastewater treatment plants during storm events. This model has been validated using both model and real data. The results show the efficiency of STORMNET as a computational tool for simulating stormwater pollution.

Neural networks for solid transport modelling in sewer systems during storm events

1996 ◽  
Vol 33 (9) ◽  
pp. 85-92 ◽  
Author(s):  
Ning Gong ◽  
Thierry Denoeux ◽  
Jean-Luc Bertrand-Krajewski
Keyword(s):  
Neural Networks ◽  
Learning Algorithm ◽  
Real Data ◽  
General Purpose ◽  
Performance Criterion ◽  
Accurate Information ◽  
Storm Events ◽  
Transport Modelling ◽  
Receiving Waters ◽  
Solid Transport

Models for solid transport in sewers during storm events are increasingly used by engineers and operators to improve their systems and the quality of receiving waters. However, a major difficulty that prevents more general use of these models is their calibration, which requires field data, accurate information about catchments and sewers, and a specific methodology. Therefore, research has been carried out to assess the ability of connectionist models to reproduce and replace usual models for use by an operator. Such models require fewer data, are self-calibrated, and very easy to use. The first stage presented in this paper consists in a comparison between neural networks and the HYPOCRAS model, using simulations of real pollutographs for single storm events. Two specific recurrent neural networks based on the HYPOCRAS model and a general-purpose recurrent multilayer network are used to simulate hydrographs and pollutographs of TSS. The learning algorithm and the performance criterion used for optimization of these networks are described in detail. Experimental results with simulated and real data are then presented.

Automatic buffer capacity based sensor for effluent quality monitoring

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.

Experience with the Relay Procedure for Tuning Controllers in Automatic Control of Chlorination

1993 ◽  
Vol 28 (11-12) ◽  
pp. 257-261
Author(s):  
M. Truett Garrett ◽  
Zaki Ahmad ◽  
Shelly Young
Keyword(s):  
Wastewater Treatment ◽  
Automatic Control ◽  
Time Constant ◽  
Wastewater Treatment Plants ◽  
Relay Feedback ◽  
Quality Of Control ◽  
Incomplete Mixing ◽  
Long Time ◽  
Chlorine Demand

The recent requirements by U.S.E.P.A. for dechlorination and biomonitoring have increased the importance of automatic control of effluent chlorination in wastewater treatment plants. Difficulties with the Ziegler-Nichols controller tuning procedure were reported at the Kyoto Workshop, 1990. Problems are caused by the noise of incomplete mixing, a long time constant, and the disturbances of changing flow and chlorine demand. The Astrom-Hagglund relay feedback procedure provides acceptable control while data is logged to determine the controller constants. Experiences in using the procedure in existing facilities (not redesigning the mixing point) and the quality of control are presented.

scholarly journals Biological Activity of Wastewater Assessed Using in Vitro Cell-Based Assays

2021 ◽  
Author(s):  
Adamo R. Petosa ◽  
Monica Nowierski ◽  
Viviane Yargeau
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Estrogenic Activity ◽  
Solid Phase ◽  
Treated Wastewater ◽  
Chemical Analyses ◽  
Untreated Wastewater ◽  
17Β Estradiol ◽  
Receiving Waters

Abstract Bioanalytical tools, namely in vitro bioassays, can be employed in tandem with chemical analyses to assess the efficacy of wastewater treatment and the potential for adverse effects from the discharges of wastewater into receiving waters. In the present study, samples of untreated wastewater (i.e. influent) and treated wastewater (i.e. effluent) were collected from two wastewater treatment plants and a wastewater treatment lagoon serving municipalities in southern Ontario, Canada. In addition, grab samples of surface water were collected downstream of the lagoon discharge. After solid phase extraction (SPE) using ion-exchange columns for basic/neutral and acidic compounds, respectively, the extracts were analyzed for a suite of 16 indicator compounds. The two SPE extracts were combined for analysis of biological responses in four in vitro cell-based bioassays. The concentrations of several indicator compounds, including the estrogens, 17β-estradiol and 17α-ethinylestradiol, were below the limits of detection. However, androstenedione and estrone were detected in several influent samples. The concentrations of these steroid hormones and some of the other indicator compounds declined during treatment but acesulfame K, carbamazepine, trimethoprim and DEET persisted in the effluent. The MTS- CellTiter 96® AQueous One Solution Cell Proliferation Assay (MTS) indicated that cell viability was not affected by exposure to the extracts. The Qiagen Nuclear Receptors 10-Pathway Reporter Array indicated that several cellular pathways were upregulated, with the greatest upregulation observed with the estrogen receptor (i.e. induction ratios 12 to 47) and the liver X receptor (i.e. induction ratios 10 to 45). The ERα CALUX assay indicated that estrogenic activity was lower in effluents compared to influents, with the greatest estrogenic activity observed for grab samples of influent from the lagoon (i.e. 56-215 ng L-1 17β-estradiol equivalents). Finally, the results of the Nrf2 Luciferase Luminescence Assay indicated a lower oxidative stress in the effluent samples. Overall, the present study demonstrates that chemical analyses are limited in their ability to predict or explain reductions in the toxicity of treated wastewater. There are thus advantages to using a combination of chemical analyses and in vitro bioassays to monitor the treatment efficiency of wastewater treatment plants and to predict the potential impacts of wastewater discharges into receiving waters.

scholarly journals Methods of reconstruction and modification of the sequencing batch reactor at municipal wastewater treatment plants in Vietnam

Vestnik MGSU ◽  
2019 ◽  
pp. 589-602 ◽  
Author(s):  
Tran Ha Quan ◽  
Elena S. Gogina
Keyword(s):  
Wastewater Treatment ◽  
Sequencing Batch Reactor ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Batch Reactor ◽  
Municipal Wastewater Treatment ◽  
Wastewater Purification ◽  
Municipal Wastewater Treatment Plants ◽  
Operation Cycle

Introduction. Vietnamese urban municipal wastewater treatment plants are mainly of aeration-type facilities. Nowadays, an aeration-type plant, the Sequencing Batch Reactor (SBR), is widely applied and possesses a number of advantages over traditional systems with suspended activated sludge. Advantages of the SBR are mainly concluded in simplicity of operation, occupied area and cost. There is a number of problems at the wastewater treatment plants; they are connected with supplying only a half of wastewater design amount for the treatment as well as with quality of the purified water that must satisfy requirements of the Vietnamese discharge standard, the Standard A. Therefore, reconstruction and modification of the SBR is the major challenger to ensure the sustained development of large Vietnamese cities and maintenance of ecological balance. Materials and methods. To enhance the efficiency of wastewater purification in the SBR, the experiments were set on reactor reconstruction and modification by two directions: (1) Technological method, i.e. applying the Biochip 25 biocarrier, and (2) Operation method, i.e. adding the anoxic phase in reactor operation cycle. Laboratory tests were conducted for each of the directions, including comparison of a typical reactor with the modified one. Results. The study resulted in obtaining an optimal amount of the BioChip biocarrier material (10 to 20 %) that increased efficiency of wastewater purification by 10 to 20 %. In addition to this, when creating an anoxic phase of the operation cycle, efficiency of nitrogen removal increased by 20 %. When the denitrification occurs under the anoxic conditions, it contributes to stabilization of ammonium nitrogen removal for daily nitrogen loading in reactor of 0.3 to 0.8 TKN kg/sludge kg. Conclusions. The suggested technology provides the quality of treated water corresponding with the Vietnamese Standard A requirements. At the present, it is planned to proceed with the experiment on the base of Vietnamese semi-industrial plant for research and appraisal of the SBR reconstruction and modification method. Acknowledgements. The authors are grateful to AKVA Control company in Samara for granted biocarrier Mutag BioChip 25 and to Associate Professor Tran Van Quang and his students, Nguyen Ngoc Phuong and Truong Quoc Dai, of Environment Protect Research Center, Danang University for support of the experiment.

scholarly journals A simple model of wastewater treatment plants for managing the quality of the Seine River

2018 ◽  
Vol 51 (18) ◽  
pp. 880-885 ◽  
Author(s):  
C.E. Robles-Rodriguez ◽  
J. Bernier ◽  
V. Rocher ◽  
D. Dochain
Keyword(s):  
Wastewater Treatment ◽  
Simple Model ◽  
Wastewater Treatment Plants ◽  
Seine River

Improving the effluent of small wastewater treatment plants by bacteria reduction and nutrient removal with an algal biofilm

2003 ◽  
Vol 48 (2) ◽  
pp. 373-380 ◽  
Author(s):  
G. Schumacher ◽  
I. Sekoulov
Keyword(s):  
Wastewater Treatment ◽  
Nutrient Removal ◽  
Wastewater Treatment Plants ◽  
High Potential ◽  
High Quality ◽  
Secondary Pollution ◽  
Algal Biofilm ◽  
Biofilm Process ◽  
Suspended Algae

In wastewater ponds, bacteria numbers decrease considerably in the case of raised algae concentrations in the effluent. This shows that algae have a high potential for bacteria reduction in wastewater. Simultaneously, algae remove nutrients from the water for the formation of biomass. However, suspended algae also cause a high secondary pollution in the effluent of wastewater treatment plants. By using attached algae, as they are frequently observed as an algal biofilm in the effluent of wastewater treatment plants, the problem of separation of algae and water can be avoided. Furthermore, the algae can be removed simply from the water. In this study the possibilities for bacteria reduction and nutrient removal were examined with the aid of an algal biofilm. The results show that an algal biofilm process can be used for cases where small amounts of wastewater should be treated and a high quality of the effluent should be attained.

scholarly journals LCA of a Membrane Bioreactor Compared to Activated Sludge System for Municipal Wastewater Treatment

Membranes ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 421
Author(s):  
Dimitra C. Banti ◽  
Michail Tsangas ◽  
Petros Samaras ◽  
Antonis Zorpas
Keyword(s):  
Wastewater Treatment ◽  
Life Cycle ◽  
Activated Sludge ◽  
Membrane Bioreactor ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Real Data ◽  
Municipal Wastewater Treatment ◽  
Conventional Activated Sludge

Membrane bioreactor (MBR) systems are connected to several advantages compared to the conventional activated sludge (CAS) units. This work aims to the examination of the life cycle environmental impact of an MBR against a CAS unit when treating municipal wastewater with similar influent loading (BOD = 400 mg/L) and giving similar high-quality effluent (BOD < 5 mg/L). The MBR unit contained a denitrification, an aeration and a membrane tank, whereas the CAS unit included an equalization, a denitrification, a nitrification, a sedimentation, a mixing, a flocculation tank and a drum filter. Several impact categories factors were calculated by implementing the Life Cycle Assessment (LCA) methodology, including acidification potential, eutrophication potential, global warming potential (GWP), ozone depletion potential and photochemical ozone creation potential of the plants throughout their life cycle. Real data from two wastewater treatment plants were used. The research focused on two parameters which constitute the main differences between the two treatment plants: The excess sludge removal life cycle contribution—where GWPMBR = 0.50 kg CO2-eq*FU−1 and GWPCAS = 2.67 kg CO2-eq*FU−1 without sludge removal—and the wastewater treatment plant life cycle contribution—where GWPMBR = 0.002 kg CO2-eq*FU−1 and GWPCAS = 0.14 kg CO2-eq*FU−1 without land area contribution. Finally, in all the examined cases the environmental superiority of the MBR process was found.

Lessons learnt from the application of a multi-variable controller for nitrogen removal in the Mekolalde wastewater treatment plant: good simulation practices in control

2014 ◽  
Vol 69 (6) ◽  
pp. 1289-1297 ◽  
Author(s):  
I. Irizar ◽  
S. Beltrán ◽  
G. Urchegui ◽  
G. Izko ◽  
O. Fernández ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Nitrogen Removal ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Real Life ◽  
Control Product ◽  
Quality Of Water ◽  
Short Period ◽  
Mathematical Modelling And Simulation

Although often perceived as tools for use by scientists, mathematical modelling and simulation become indispensable when control engineers have to design controllers for real-life wastewater treatment plants (WWTPs). Nonetheless, the design of effective controllers in the wastewater domain using simulations requires effects, such as the nonlinearity of actuators, the time response of sensors, plant model uncertainties, etc. to have been reproduced beforehand. Otherwise, control solutions verified by simulation can completely underperform under real conditions. This study demonstrates that, when all the above effects are included at the outset, a systematic use of simulations guarantees high quality controllers in a relatively short period of time. The above is exemplified through the Mekolalde WWTP, where a comprehensive simulation study was conducted in order to develop a control product for nitrogen removal. Since its activation in May 2011, the designed controller has been permanently working in the plant which, from this time onwards, has experienced significant improvements in the quality of water discharges combined with a lower utilization of electricity for wastewater treatment.

Sign in / Sign up

Export Citation Format

Share Document