A neural network approach for on-line fault detection of nitrogen sensors in alternated active sludge treatment plants

2010 ◽  
Vol 62 (12) ◽  
pp. 2760-2768 ◽  
Author(s):  
F. Caccavale ◽  
P. Digiulio ◽  
M. Iamarino ◽  
S. Masi ◽  
F. Pierri
Keyword(s):  
Neural Networks ◽  
Fault Detection ◽  
Treatment Plant ◽  
Weather Conditions ◽  
Active Sludge ◽  
Measured Concentration ◽  
Neural Network Approach ◽  
Sludge Treatment ◽  
The Difference ◽  
Set Up

In this paper, an effective strategy for fault detection of nitrogen sensors in alternated active sludge treatment plants is proposed and tested on a simulated set-up. It is based on two predictive neural networks, which are trained using a historical set of data collected during fault-free operation of a wastewater treatment plant and their ability to predict reduced (ammonium) and oxidized (nitrates and nitrites) nitrogen is tested. The neural networks are also characterized by good generalization ability and robustness with respect to the influent variability with time and weather conditions. Then, simulations have been carried out imposing different kinds of fault on both sensors, as isolated spikes, abrupt bias and increased noise. Processing of residuals, based on the difference between measured concentration values and neural networks predictions, allows a quick revealing of the fault as well as the isolation of the corrupted sensor.

Hurdles in the investigation of influent fractionation for measurement campaigns under diluted wastewater conditions

2016 ◽  
Vol 74 (12) ◽  
pp. 2958-2969
Author(s):  
Youri Amerlinck ◽  
Ellen Vanassche ◽  
Hélène Versluys ◽  
Ingmar Nopens
Keyword(s):  
Treatment Plant ◽  
Weather Conditions ◽  
Low Load ◽  
Good Characterization ◽  
Set Up ◽  
The Impact ◽  
Measurement Campaigns ◽  
Load Conditions ◽  
Insufficient Sensitivity

Evaluating the performance of a wastewater treatment plant (WWTP) requires a good characterization of the biodegradable substrate entering the plant. As is generally acknowledged, the wastewater characteristics under rain or storm weather conditions vary significantly from dry weather conditions but this is rarely accounted for in modelling exercises. In order to address this defect, a measurement campaign was set up and samples were analysed using respirometric assays. In this paper, some hurdles regarding measurement campaigns under dilute wastewater conditions and a better exploration of the impact of using respirometric assays are described and discussed. The dependence of the heterotrophic yield on different substrates severely hampers the evaluation of the respirograms under dilute wastewater conditions. In addition, the low load conditions limit the application of the assays due to insufficient sensitivity of the experiment and uncontrolled oxygen inputs. The results clearly demonstrate the need for further research in order to allow for a proper evaluation of WWTP performance under rain and storm weather conditions.

Modeling activated sludge mass transfer in a treatment plant

1999 ◽  
Vol 39 (4) ◽  
pp. 29-36 ◽  
Author(s):  
C. Joannis ◽  
M. Aumond ◽  
S. Dauphin ◽  
G. Ruban ◽  
A. Deguin ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Treatment Plant ◽  
Weather Conditions ◽  
Measured Data ◽  
Dimensional Model ◽  
Sludge Treatment ◽  
One Dimensional ◽  
Times Series ◽  
Secondary Clarifier ◽  
Sludge Settleability

To keep overflows of raw effluent to a minimum during wet weather conditions, we investigated the ability of a secondary clarifier of an activated sludge treatment plant to accept hydraulic overloads without being washed out. The experiments, which were conducted on a full scale 8000 p.e. treatment plant, showed the feasibility of the project, and suggested some features, which were included in a one-dimensional model designed to study the behavior of the sludge blanket in the clarifier. This model takes into account the effect of convection currents, suspected to play an important part in the rising of sludge blankets. The sensitivity of the model to sludge settleability prevented its use with long times-series, unless a continuous recalibration was performed. Nevertheless, this model appears very interesting for a better understanding of the dynamics of the clarifier, as described by measured data. It could be used in relation with sensors to improve the operation of the treatment plant.

Fault Diagnosis of Gas Turbine Engines by Using Dynamic Neural Networks

2010 ◽  
Author(s):  
Rasul Mohammadi ◽  
Esmaeil Naderi ◽  
Khashayar Khorasani ◽  
Shahin Hashtrudi-Zad
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Fault Detection ◽  
Gas Turbine ◽  
Network Architecture ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Dynamic Neural Networks ◽  
Feed Forward ◽  
The Difference

This paper presents a novel methodology for fault detection in gas turbine engines based on the concept of dynamic neural networks. The neural network structure belongs to the class of locally recurrent globally feed-forward networks. The architecture of the network is similar to the feed-forward multi-layer perceptron with the difference that the processing units include dynamic characteristics. The dynamics present in these networks make them a powerful tool useful for identification of nonlinear systems. The dynamic neural network architecture that is described in this paper is used for fault detection in a dual-spool turbo fan engine. A number of simulation studies are conducted to demonstrate and verify the advantages of our proposed neural network diagnosis methodology.

Production of fuels on the basis of sewage sludge through conditioning using high calorific value fractions

2008 ◽  
Vol 3 (1) ◽  
Author(s):  
Karl-Georg Schmelz ◽  
Anja Reipa ◽  
Hartmut Meyer
Keyword(s):  
Sewage Sludge ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Calorific Value ◽  
Fluidised Bed ◽  
Sludge Treatment ◽  
Heating Value ◽  
Fine Coal ◽  
Used Cars ◽  
Plastic Components

Emschergenossenschaft and Lippeverband operate 59 wastewater treatment plants which produce approx. 100,000 Mg TS of sewage sludge each year. Using sludge pressure pipelines, about 60 % of this sludge are transported to the central sludge treatment plant in Bottrop. The digested sludges are conditioned using fine coal and polymers and are dewatered using membrane filters. By adding coal, the heating value of the sludge is raised which enables autothermal combustion of the dewatered sludges in fluidised bed furnaces at the central sludge treatment plant. In order to replace coal, a fossil fuel, as conditioning agent, experiments were conducted using alternative materials with high heating values. The addition of shredder fluff agglomerates proved to be particularly successful. Shredder fluff agglomerates are a residue from the recycling of used cars and are generated in a multistage process (e.g. Volkswagen-SiCon Process) by separating the light shredder fraction (plastic components etc.) from the total shredder fluff. The fibrous material is outstandingly suitable for improving the dewaterability and for sufficiently raising the heating value of the dewatered sludge in order to enable autothermal combustion. Since first experiments showed very positive results, a full-scale long-term test-run will take place in 2007.

Behaviour of Mechanically Blended Return-Sludge in Absence of Substrate

1970 ◽  
Vol 5 (1) ◽  
pp. 34-54
Author(s):  
Shyam D. Bokil ◽  
Jatinder K. Bewtra
Keyword(s):  
Activated Sludge ◽  
Suspended Solids ◽  
Treatment Plant ◽  
Aeration Rate ◽  
Batch Experiments ◽  
Sludge Treatment ◽  
Waring Blender ◽  
Settling Characteristics

Abstract Nine sets of batch experiments, each of ten to twelve days duration, were conducted in the laboratory on return-sludge samples collected from activated sludge treatment plant at Windsor. The thickened sludge samples were blended daily in a waring blender and were continuously aerated in twelve-litres capacity jars. Parallel runs were made on control sludge samples which were not blended. Amongst the parameters varied were the speed and frequency of blending and the aeration rate. The effects of these variables on progressive bio-degradation of volatile suspended solids and the settling characteristics of the sludge were determined. Blended sludge showed significant improvement in the rate of bio-degradation and its settling characteristics as compared to the control unblended sludge

Deemulsification of Water-in-Oil Emulsion with Sludges

1987 ◽  
Vol 22 (3) ◽  
pp. 437-443 ◽  
Author(s):  
N. Kosaric ◽  
Z. Duvnjak
Keyword(s):  
Activated Sludge ◽  
Room Temperature ◽  
Petroleum Refinery ◽  
Treatment Plant ◽  
Granular Sludge ◽  
Activated Sludge Process ◽  
Sludge Treatment ◽  
Oil Emulsion ◽  
Water In Oil Emulsion ◽  
Aerobic Sludge

Abstract Aerobic sludge from a municipal activated sludge treatment plant, sludge from a conventional municipal anaerobic digester, aerobic sludge from an activated sludge process of a petroleum refinery, and granular sludge from an upflow sludge blanket reactor (USBR) were tested in the deemulsification of a water-in-oil emulsion. All sludges except the last one, showed a good deemulsification capability and could he used for a partial deemulsification of such emulsions. The rate and degree of the deemulsifications increased with an increase in sludge concentrations. The deemulsifications were faster at 85°C and required smaller amounts of sludge than in the case of the deemulsifications at room temperature. An extended stirring (up to a certain limit) in the course of the dispersion of sludge emulsion helped the deemulsification. Too vigorous agitation had an adverse effect. The deemulsification effect of sludge became less visible with an increase in the dilution of emulsion which caused an increase in its spontaneous deemulsification.

Solids Concentrations in a Treatment Plant Effluent

1992 ◽  
Vol 26 (9-11) ◽  
pp. 2543-2546
Author(s):  
M. Defrain ◽  
F. Schmidt
Keyword(s):  
Waste Water ◽  
Activated Sludge ◽  
Federal Republic ◽  
Treatment Plant ◽  
Analysis Procedure ◽  
Process Water ◽  
Federal Republic Of Germany ◽  
Output Variable ◽  
Sludge Treatment ◽  
Sewerage Network

In the calculations customarily used to dimension nitrification and denitrification plants in the Federal Republic of Germany, solids in the influent of the biological stage represent a significant output variable. Numerous modified methods based on nationally and internationally standardized analysis procedures are available to determine solids concentrations in waste-water. Tests showed that different values are measured depending on the method of analysis employed. Harmonization of the analysis procedure is advisable to ensure comparable conditions for the calculation of activated sludge tank volumes. The solids reaching a treatment plant originate from two main sources. Filterable materials are passed to the treatment plant via the preceding sewerage network with its industrial and commercial users, but are also carried by process water from sludge treatment. The influence of process water on wastewater composition is illustrated by reference to the Wuppertal-Buchenhofen treatment plant.

Evaluation of the alternative treatment processes to upgrade an Opium alkaloid wastewater treatment plant

2000 ◽  
Vol 41 (1) ◽  
pp. 223-230 ◽  
Author(s):  
M.F. Sevimli ◽  
A.F. Aydin ◽  
Ì. Öztürk ◽  
H.Z. Sarikaya
Keyword(s):  
Activated Sludge ◽  
Alternative Treatment ◽  
Treatment Plant ◽  
Post Treatment ◽  
Anaerobic Sludge ◽  
Processing Plant ◽  
Two Stage ◽  
Sludge Treatment ◽  
Treatment Processes ◽  
Opium Alkaloid

The aim of this study is to characterize the wastewater from an opium alkaloid processing plant and to evaluate alternative treatment techniques to upgrade an existing full-scale biological activated sludge treatment plant having problems of high residual COD and unacceptable dark brown color. In this content firstly, long term operational records of the two stage aerobic activated sludge treatment plant of the opium alkaloid factory located in Afyon province of Turkiye were evaluated. The operating results for the last three years were statistically analyzed and median and 95-percentile values were determined for the parameters including chemical and biological oxygen demand (COD and BOD5) and treatment efficiencies. Specific wastewater generation was found as 6.7 m3 per ton of the opium capsule processed. In the following stage of the study, three additional treatment processes were experimentally tested: anaerobic pretreatment, post treatment of aerobically treated effluents with lime and ozone. Pilot scale upflow anaerobic sludge blanket reactor (UASBR) experiments have demonstrated that about 70 percent of the incoming COD can be removed anaerobically. Chemical treatability studies with lime for the aerobically treated effluent have shown that about 78 percent color and 46 percent COD removals can be obtained with lime dosage of 25 gl−1. Post treatment of the effluents of the existing two stage aerobic treatment with ozone also resulted in significant color and COD reduction.

Heating up trickling filters to tackle cold weather conditions

2000 ◽  
Vol 41 (1) ◽  
pp. 163-166 ◽  
Author(s):  
W. Gebert ◽  
P.A. Wilderer
Keyword(s):  
Waste Heat ◽  
Treatment Plant ◽  
Weather Conditions ◽  
Pilot Scale ◽  
Cold Weather ◽  
Filling Material ◽  
Trickling Filter ◽  
Biofilm Thickness ◽  
Trickling Filters ◽  
Biofilm Support

The investigated effects of heating the filling material in trickling filters were carried out at the Ingolstadt wastewater treatment plant, Germany. Two pilot scale trickling filters were set up. Heat exchanger pipings were embedded in the filter media of one of these trickling filters, and the temperature in the trickling filter was raised. The other trickling filter was operated under normal temperature conditions, and was used as a control. The results clearly demonstrate that the performance of trickling filters cannot be constantly improved by heating the biofilm support media. A sustained increase of the metabolic rates did not occur. The decrease of the solubility of oxgen in water and mass transfer limitations caused by an increase of the biofilm thickness are the main reasons for that. Thus, the heating of trickling filters (e.g. by waste heat utilization) in order to increase the capacity of trickling filters under cold weather conditions cannot be recommended.

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