Nested control loop configuration for a three stage biological wastewater treatment process

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Pothuraju Maheswari ◽  
Abdul Gaffar Sheik ◽  
E. S. S. Tejaswini ◽  
Seshagiri Rao Ambati
Keyword(s):  
Wastewater Treatment ◽  
Control Strategies ◽  
Treatment Plant ◽  
Ammonia Concentration ◽  
Wastewater Treatment Process ◽  
Loop Control ◽  
Effluent Quality ◽  
Nitrogen Concentrations ◽  
Control Loop Configuration ◽  
Anoxic Zones

AbstractIn every urban infrastructure, Wastewater Treatment Plant (WWTP) requires special attention because of its adverse effects on the environment and also for resource recovery. Therefore, there arises a need to treat the wastewater in order to meet the effluent norms prior to discharge. Different control strategies and various scenarios of plant layout can be tested and evaluated through modelling and simulation studies on the benchmark layouts. In this paper, a feedforward nested loop control structure based on ammonia concentration is implemented on Benchmark Simulation Model (BSM1-P) developed based on Activated Sludge Model No. 3 bioP (ASM3bioP) for controlling the dissolved oxygen in aerobic zones and nitrate level in anoxic zones and nutrient removal by adding two anaerobic zones. By using this control strategy, pumping energy, percentage violations of ammonia and nitrogen concentrations in the effluent, and effluent quality are reduced effectively.

scholarly journals Design of Feedback Control Strategies in a Plant-Wide Wastewater Treatment Plant for Simultaneous Evaluation of Economics, Energy Usage, and Removal of Nutrients

Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6386
Author(s):  
Abdul Gaffar Sheik ◽  
Eagalapati Tejaswini ◽  
Murali Mohan Seepana ◽  
Seshagiri Rao Ambati ◽  
Montse Meneses ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plant ◽  
Removal Rate ◽  
Control Strategies ◽  
Treatment Plant ◽  
Feedback Signal ◽  
Operational Cost ◽  
Effluent Quality ◽  
Control Framework ◽  
Pi Controllers

Simultaneous removal of nitrogen and phosphorous is a recommended practice while treating wastewater. In the present study, control strategies based on proportional-integral (PI), model predictive control (MPC), and fuzzy logic are developed and implemented on a plant-wide wastewater treatment plant. Four combinations of control frameworks are developed in order to reduce the operational cost and improve the effluent quality. As a working platform, a Benchmark simulation model (BSM2-P) is used. A default control framework with PI controllers is used to control nitrate and dissolved oxygen (DO) by manipulating the internal recycle and oxygen mass transfer coefficient (KLa). Hierarchical control topology is proposed in which a lower-level control framework with PI controllers is implemented to DO in the sixth reactor by regulating the KLa of the fifth, sixth, and seventh reactors, and fuzzy and MPC are used at the supervisory level. This supervisory level considers the ammonia in the last aerobic reactor as a feedback signal to alter the DO set-points. PI-fuzzy showed improved effluent quality by 21.1%, total phosphorus removal rate by 33.3% with an increase of operational cost, and a slight increase in the production rates of greenhouse gases. In all the control design frameworks, a trade-off is observed between operational cost and effluent quality.

scholarly journals PI and Fuzzy Control for P-removal in Wastewater Treatment Plant

2015 ◽  
Vol 10 (6) ◽  
pp. 176 ◽  
Author(s):  
Hongyang Xu ◽  
Ramon Vilanova
Keyword(s):  
Wastewater Treatment ◽  
Control Strategy ◽  
Wastewater Treatment Plant ◽  
Control Strategies ◽  
Treatment Plant ◽  
Wastewater Treatment Process ◽  
Fuzzy Controllers ◽  
Linear Character ◽  
N Removal ◽  
Pi Controllers

Due to the complex and non linear character, wastewater treatment process is difficult to be controlled. The demand for removing the pollutant, especially for nitrogen (N) and phosphorus (P), as well as reducing the cost of wastewater treatment plant is an important research theme recently. Thus, in this paper, the benchmark proposed default control strategy and 10 additional control strategies are applied on the combined biological P and N removal Benchmark Simulation Model No.1 (BSM1-P). In addition, according to the results of applying PI controllers, as usual, we also chose the group with the better performance, as well as the default control strategy, to replace the PI controllers with fuzzy controllers. In this way, it can be seen that in all cases the quality of effluent of the controlled process could be improved in some degree; and the fuzzy controllers get a better phosphorus removal.

scholarly journals A supervisory fuzzy logic control scheme to improve effluent quality of a wastewater treatment plant

2021 ◽  
Author(s):  
S. Saravana Kumar ◽  
K. Latha
Keyword(s):  
Fuzzy Logic ◽  
Wastewater Treatment ◽  
Fuzzy Logic Controller ◽  
Wastewater Treatment Plants ◽  
Control Strategies ◽  
Treatment Plant ◽  
Vital Role ◽  
Effluent Quality ◽  
Control Scheme ◽  
Control Schemes

Abstract The application of control strategies in wastewater treatment plants has increased to improve its performance of treating the influent. Fuzzy Logic controller plays a vital role in this work and the simulation work is being carried out in Benchmark simulation model no.1 (BSM1) framework. The attempted work proposes two control schemes with the objectives of improving the effluent quality and minimizing the number of measurements taken from the plant. The design of fuzzy control schemes is based on 5 inputs and 6 outputs in order to accomplish the objectives. Experimental results show improvement in the effluent quality and increase in the efficacy of the control system. The proposed design is implemented using MATLAB with the adaptation of 2014a.

scholarly journals Disturbance rejection control for the dissolved oxygen in a wastewater treatment process

2020 ◽  
Vol 53 (5-6) ◽  
pp. 899-907 ◽  
Author(s):  
Wei Wei ◽  
Nan Chen ◽  
Min Zuo ◽  
Zai-Wen Liu
Keyword(s):  
Wastewater Treatment ◽  
Dissolved Oxygen ◽  
Canonical Form ◽  
Disturbance Rejection ◽  
Wastewater Treatment Plants ◽  
High Energy ◽  
Wastewater Treatment Process ◽  
Loop Control ◽  
Effluent Quality ◽  
Disturbance Rejection Control

In wastewater treatment processes, the concentration of dissolved oxygen affects the performance of wastewater treatment directly. It is one of the key factors that determines effluent quality of the wastewater treatment. However, a simple closed-loop control has a high-energy consumption, and it cannot guarantee the effluent quality due to large perturbations in wastewater treatment plants, such as the influent rate, the temperature, and the complex biochemical reactions. In this paper, a new disturbance rejection controller is designed to address those perturbations. Dynamics of dissolved oxygen is transformed into a controllable canonical form. Discrepancy between the dissolved oxygen dynamics and the controllable canonical form is estimated by a disturbance observer and compensated by a control law. Stability and the bound of tracking errors are obtained. Finally, numerical results on the benchmark simulation model number 1 are presented to confirm the proposed method.

FAST-MODE REAL-TIME SIMULATOR FOR THE WASTEWATER TREATMENT PROCESS

1994 ◽  
Vol 30 (4) ◽  
pp. 191-197 ◽  
Author(s):  
Mieczyslaw Metzger
Keyword(s):  
Wastewater Treatment ◽  
Industrial Wastewater ◽  
Treatment Process ◽  
Control Strategies ◽  
Treatment Plant ◽  
Optimal Decision ◽  
Simulation Experiments ◽  
Wastewater Treatment Process ◽  
Cyanide Concentration ◽  
Optimal Decision Making

Process connected simulation of a process is very useful for optimal decision making. The problem of computer aided operator support in the case of a sudden augmentation of cyanide concentration in the inlet flow of a big industrial wastewater treatment plant is presented in the work. By using simulation experiments the operator of the process may check the consequences of the operating control strategies before the emergency in the real-world process occurs.

scholarly journals Applying performance indices in plantwide modelling for a comparative study of wastewater treatment plant operational strategies

Water SA ◽  
2018 ◽  
Vol 44 (4 October) ◽  
Author(s):  
Justine De Ketele ◽  
Dries Davister ◽  
David S Ikumi
Keyword(s):  
Wastewater Treatment ◽  
Mathematical Models ◽  
Wastewater Treatment Plant ◽  
Waste Treatment ◽  
Control Strategies ◽  
Treatment Plant ◽  
Expert Advice ◽  
Energy Costs ◽  
Performance Indices ◽  
Effluent Quality

Achievement of good effluent quality is always the main goal for wastewater treatment plant (WWTP) systems. However, these WWTPs have developed further objectives that include efficient design and strategic control options, with the prospect of their conversion into waste resource recovery facilities (WRRFs) that operate on reduced energy costs. With all these aspects becoming an intrinsic part of waste treatment, mathematical models that simulate WWTP unit processes are becoming of increasing relevance for the achievement of WRRF goals (including good effluent quality, low energy costs and nutrient recovery). It is expected that these mathematical models will benefit potential future applications of automation process control, which have also been developing rapidly with the availability of more reliable and affordable sensors. However, simulated automation control strategies require a thorough evaluation protocol to ensure their viability prior to being adopted as efficient operation control measures. This study considers the comparison of different control strategies implemented on a standard WWTP layout, for plant optimization. The initial task was to define performance indices, effluent quality index (EQI) and operation cost index (OCI), based on a previous investigation by the International Water Association (IWA) benchmark simulation modelling (BSM) task group. These performance indices were then used to evaluate the following strategies: (i) adding a fermentation tank, (ii) dosing flocculant and (iii) implementing a balancing tank. A control strategy was only assumed to be effective with improvement or maintenance of effluent quality. Overall, the evaluation exercise proved to be useful for providing expert advice on efficiency of proposed waste treatment system layouts, towards determination of the best configuration of future WRRFs. For instance, it was notable that significant organic strength is needed for removal of nutrients recycled back from the anaerobic digestion (AD) system into the activated sludge (AS) – hence alternate methods to put the nutrient-rich outflow from the AD system to good use are required.

Implementation of storage tanks on the COST 624 benchmark

2002 ◽  
Vol 45 (4-5) ◽  
pp. 159-166 ◽  
Author(s):  
M.N. Pons ◽  
J.P. Corriou
Keyword(s):  
Wastewater Treatment ◽  
Control Strategies ◽  
Treatment Plant ◽  
Weather Condition ◽  
Weather Conditions ◽  
Storage Tanks ◽  
Effluent Quality ◽  
The Cost ◽  
Operation Cost

To test the improvement that can be expected in terms of effluent quality of an wastewater treatment plant by activated sludge, an equalisation tank and a storm tank, designed to damp the influent variations under different weather conditions, have been implemented in front of a benchmark plant used to evaluate control strategies. The equalisation tank improves significantly the effluent quality in any weather condition but at a high operation cost due to extra pumping, while the storm tank without by-pass improves the effluent quality in rainy periods with a small increase in cost operation over the no tank case.

scholarly journals Persulfate mediated solar photo-Fenton aiming at wastewater treatment plant effluent improvement at neutral PH: emerging contaminant removal, disinfection, and elimination of antibiotic-resistant bacteria

2021 ◽  
Author(s):  
Maria Clara V. M. Starling ◽  
Elizângela P. Costa ◽  
Felipe A. Souza ◽  
Elayne C. Machado ◽  
Juliana Calábria de Araujo ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Resistant Bacteria ◽  
Antibiotic Resistant Bacteria ◽  
Antibiotic Resistant ◽  
E Coli ◽  
Effluent Quality ◽  
Neutral Ph ◽  
Wastewater Treatment Plant Effluent

AbstractThis work investigated an innovative alternative to improve municipal wastewater treatment plant effluent (MWWTP effluent) quality aiming at the removal of contaminants of emerging concern (caffeine, carbendazim, and losartan potassium), and antibiotic-resistant bacteria (ARB), as well as disinfection (E. coli). Persulfate was used as an alternative oxidant in the solar photo-Fenton process (solar/Fe/S2O82−) due to its greater stability in the presence of matrix components. The efficiency of solar/Fe/S2O82− at neutral pH using intermittent iron additions is unprecedented in the literature. At first, solar/Fe/S2O82− was performed in a solar simulator (30 W m−2) leading to more than 60% removal of CECs, and the intermittent iron addition strategy was proved effective. Then, solar/Fe/S2O82− and solar/Fe/H2O2 were compared in semi-pilot scale in a raceway pond reactor (RPR) and a cost analysis was performed. Solar/Fe/S2O82− showed higher efficiencies of removal of target CECs (55%), E. coli (3 log units), and ARB (3 to 4 log units) within 1.9 kJ L−1 of accumulated irradiation compared to solar/Fe/H2O2 (CECs, 49%; E. coli, 2 log units; ARB, 1 to 3 log units in 2.5 kJ L−1). None of the treatments generated acute toxicity upon Allivibrio fischeri. Lower total cost was obtained using S2O82− (0.6 € m−3) compared to H2O2 (1.2 € m−3). Therefore, the iron intermittent addition aligned to the use of persulfate is suitable for MWWTP effluent quality improvement at neutral pH.

Integrated modelling: comparison of state variables, processes and parameters in sewer and wastewater treatment plant models

1997 ◽  
Vol 36 (5) ◽  
pp. 373-380 ◽  
Author(s):  
C. Fronteau ◽  
W. Bauwens ◽  
P.A. Vanrolleghem
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Drainage System ◽  
Integrated Modelling ◽  
Urban Drainage ◽  
State Variables ◽  
Sewer System ◽  
Wastewater Treatment Process ◽  
Urban Drainage System

All the parts of an urban drainage system, i.e. the sewer system, the wastewater treatment plant (WWTP) and the river, should be integrated into one single model to assess the performance of the overall system and for the development of design and control strategies assisting in its sustainable and cost effective management. Existing models for the individual components of the system have to be merged in order to develop the integrated tool. One of the problems arising from this methodology is the incompatibility of state variables, processes and parameters used in the different modelling approaches. Optimisation of an urban drainage system, and of the wastewater treatment process in particular, requires a good knowledge of the wastewater composition. As important transformations take place between the emission from the household and the arrival at the treatment facility, sewer models should include these transformations in the sewer system. At present, however, research is still needed in order to increase our knowledge of these in-sewer processes. A comparison of the state variables, processes and parameters has been carried out in both sewer models (SMs) and activated sludge models (ASMs). An ASM approach is used for the description of reactions in sewer models. However, a difference is found in the expression for organic material (expressed in terms of BOD) and heterotrophic biomass is absent as a state variable, resulting in differences in processes and parameters. Reconciliation of both the models seems worthwhile and a preliminary solution is suggested in this paper.

Sign in / Sign up

Export Citation Format

Share Document