Using sequencing batch biofilm reactor (SBBR) to treat ABS wastewater

2000 ◽  
Vol 41 (4-5) ◽  
pp. 433-440 ◽  
Author(s):  
C.-N. Chang ◽  
H.R. Chen ◽  
C.H. Huang ◽  
A. Chao
Keyword(s):  
Real Time ◽  
Cost Effective ◽  
Optimal Growth ◽  
Fixed Time ◽  
Biofilm Reactor ◽  
Real Time Control ◽  
Time Control ◽  
Sequencing Batch Biofilm Reactor ◽  
Time Operation ◽  
Real Time Operation

Ratio of total Kjeldahl Nitrogen to COD for ABS (acrylnitrile, butadiene and styrene) wastewater is in a range of 0.12–0.17, which is significantly higher than that needed for optimal growth of an activated sludge. In this work, an automated Sequencing Batch Biofilm Reactor (SBBR) system at lab-scale is applied to reduce the amount of ABS; this system is controlled by an on-line monitoring of oxidation-reduction potential (ORP). A comparison of the operation efficiency for the lab-scale SBBR operated with the control of fix-time method and ORP-based real-time automatic method is presented. The results show that the system ORP can be used as an available parameter for achieving a real-time operation and control of the lab-scale SBBR. It is found that the reaction time is reduced of 11.1–55.2% if an ORP-based real-time control is used, instead of the fixed-time control. Also, the SBBR system is made more efficient and cost-effective.

Real-time implementation of an algorithm for self-repairing control systems based on LQG optimization

1998 ◽  
Vol 212 (1) ◽  
pp. 27-35
Author(s):  
F Caliskan
Keyword(s):  
Real Time ◽  
Real Time Control ◽  
Linear Quadratic ◽  
Control Laws ◽  
Time Control ◽  
Time Operation ◽  
Cent Efficiency ◽  
Real Time Operation ◽  
Detection And Diagnosis ◽  
Aircraft Application

In this paper a self-repairing real-time control (SRC) system based on LQG (Linear Quadratic Gaussian) optimization is proposed. Its transputer implementation and a real-time aircraft application are presented. The SRC system is composed of the monitoring of the control system, the detection and diagnosis of the failure and the reconfiguration of the control laws. The proposed SRC system is suitable for real-time operation because of the parallel nature of its architecture. The INMOS multitransputer implementation of the SRC applied to an aircraft model provides 56 per cent efficiency compared to a single-transputer implementation.

Semi-Direct Injection Engine Modeling for Real Time Control

2011 ◽  
Vol 347-353 ◽  
pp. 2504-2510 ◽  
Author(s):  
Yuh Yih Wu ◽  
Bo Chiuan Chen ◽  
Anh Trung Tran
Keyword(s):  
Real Time ◽  
Direct Injection ◽  
Intake Manifold ◽  
Combustion Model ◽  
Zone Model ◽  
Real Time Control ◽  
Lean Burn ◽  
Time Control ◽  
Time Operation ◽  
Real Time Operation

The Semi-Direct Injection (SDI) system has been shown to improve small engine efficiency and exhaust by utilizing a lean burn method. In order to better understand how to more readily utilize the control systems in SDI engine, the real-time operation of an SDI engine was modeled. A charging model was developed by using a filling-and-emptying model to simulate air exchange in an engine, including varying the intake manifold structure. A single-zone model was applied to a combustion model and the effects of air/fuel ratio and swirl ratio on combustion duration were also considered. The calculated results of the intake manifold pressure, heat release rate, and cylinder pressure were compared with the experimental data. The results of this study show that this modeling process approximates reality.

Applying real-time control to enhance the performance of nitrogen removal in the continuous-flow SBR system

1998 ◽  
Vol 38 (3) ◽  
pp. 271-280 ◽  
Author(s):  
Ruey-Fang Yu ◽  
Shu-Liang Liaw ◽  
Cheng-Nan Chang ◽  
Wan-Yuan Cheng
Keyword(s):  
Wastewater Treatment ◽  
Real Time ◽  
Nitrogen Removal ◽  
Retention Time ◽  
Continuous Flow ◽  
Real Time Control ◽  
Time Control ◽  
Time Operation ◽  
Real Time Operation ◽  
Wastewater Treatment Systems

Conventional operations of wastewater treatment systems use the concepts of steady-state control, and often lead to unnecessary resource consumption for maintaining system functions. Real-time control was examined as a useful approach for improving the operation of wastewater treatment systems. This paper presents the application of real-time control to enhance the performance of nitrogen removal in a continuous-flow SBR system. A real-time control system combining on-line measurement of ORP and pH with Artificial Neural Network (ANN) model was proposed to carry out unsteady-state regulation of the hydraulic retention time of different operation phases. The result of this study shows that the performance of nitrogen removal was enhanced under real-time operation. Compared with fixed-time operation, the retention time of aerobic and anoxic phases can be reduced by approximately 45% and 15.5% in real-time operation respectively, also meaning that 45% aeration energy can be saved. The real-time operation also reveals a higher total nitrogen removal in a relative short retention time. Moreover, some dynamics and kinetics of nitrogen were investigated. These indicate the occurrence of nitrite-type nitrification under real-time operation. This nitrite-type nitrification results in the enhancement of denitrification performance with less carbon resource requirement and higher denitrification efficiency.

scholarly journals Model-Based Optimisation and Control Strategy for the Primary Drying Phase of a Lyophilisation Process

Pharmaceutics ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 181 ◽  
Author(s):  
Brecht Vanbillemont ◽  
Niels Nicolaï ◽  
Laurens Leys ◽  
Thomas De Beer
Keyword(s):  
Real Time ◽  
Control Strategy ◽  
Freeze Drying ◽  
Fixed Time ◽  
Chamber Pressure ◽  
Interface Temperature ◽  
Real Time Control ◽  
Choked Flow ◽  
Model Based ◽  
Time Control

The standard operation of a batch freeze-dryer is protocol driven. All freeze-drying phases (i.e., freezing, primary and secondary drying) are programmed sequentially at fixed time points and within each phase critical process parameters (CPPs) are typically kept constant or linearly interpolated between two setpoints. This way of operating batch freeze-dryers is shown to be time consuming and inefficient. A model-based optimisation and real-time control strategy that includes model output uncertainty could help in accelerating the primary drying phase while controlling the risk of failure of the critical quality attributes (CQAs). In each iteration of the real-time control strategy, a design space is computed to select an optimal set of CPPs. The aim of the control strategy is to avoid product structure loss, which occurs when the sublimation interface temperature ( T i ) exceeds the the collapse temperature ( T c ) common during unexpected disturbances, while preventing the choked flow conditions leading to a loss of pressure control. The proposed methodology was experimentally verified when the chamber pressure and shelf fluid system were intentionally subjected to moderate process disturbances. Moreover, the end of the primary drying phase was predicted using both uncertainty analysis and a comparative pressure measurement technique. Both the prediction of T i and end of primary drying were in agreement with the experimental data. Hence, it was confirmed that the proposed real-time control strategy is capable of mitigating the effect of moderate disturbances during batch freeze-drying.

CAN Security: Cost-Effective Intrusion Detection for Real-Time Control Systems

2014 ◽  
Author(s):  
Satoshi Otsuka ◽  
Tasuku Ishigooka ◽  
Yukihiko Oishi ◽  
Kazuyoshi Sasazawa
Keyword(s):  
Intrusion Detection ◽  
Control Systems ◽  
Real Time ◽  
Cost Effective ◽  
Real Time Control ◽  
Time Control

scholarly journals Flexibility Management with Virtual Batteries of Thermostatically Controlled Loads: Real-Time Control System and Potential in Spain

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1711
Author(s):  
Alejandro Martín-Crespo ◽  
Sergio Saludes-Rodil ◽  
Enrique Baeyens
Keyword(s):  
Renewable Energy ◽  
Control System ◽  
Real Time ◽  
Renewable Energy Sources ◽  
Cost Effective ◽  
Energy Sources ◽  
Frequency Regulation ◽  
Real Time Control ◽  
Time Control ◽  
Thermostatically Controlled Loads

Load flexibility management is a promising approach to face the problem of balancing generation and demand in electrical grids. This problem is becoming increasingly difficult due to the variability of renewable energies. Thermostatically-controlled loads can be aggregated and managed by a virtual battery, and they provide a cost-effective and efficient alternative to physical storage systems to mitigate the inherent variability of renewable energy sources. However virtual batteries require that an accurate control system is capable of tracking frequency regulation signals with minimal error. A real-time control system allowing virtual batteries to accurately track frequency or power signals is developed. The performance of this controller is validated for a virtual battery composed of 1000 thermostatically-controlled loads. Using virtual batteries equipped with the developed controller, a study focused on residential thermostatically-controlled loads in Spain is performed. The results of the study quantify the potential of this technology in a country with different climate areas and provides insight about the feasibility of virtual batteries as enablers of electrical systems with high levels of penetration of renewable energy sources.

scholarly journals Electrolyzer Modeling and Real-Time Control for Optimized Production of Hydrogen Gas

2020 ◽  
Author(s):  
Benjamin Flamm ◽  
Christian Peter ◽  
Felix N. Büchi ◽  
John Lygeros
Keyword(s):  
Real Time ◽  
Nonlinear Models ◽  
Cost Effective ◽  
Hydrogen Gas ◽  
Real Time Control ◽  
Actual System ◽  
Thermal Dynamics ◽  
Time Operation ◽  
Effective Manner ◽  
Production Of Hydrogen

<pre>We present a method that operates an electrolyzer to meet the demand of a hydrogen refueling station in a cost-effective manner by solving a model-based optimal control problem. To formulate the underlying problem, we first conduct an experimental characterization of a Siemens SILYZER 100 polymer electrolyte membrane electrolyzer with \SI{100}{\kilo \watt} of rated power. We run experiments to determine the electrolyzer's conversion efficiency and thermal dynamics as well as the overload-limiting algorithm used in the electrolyzer. The resulting detailed nonlinear models are used to design a real-time optimal controller, which is then implemented on the actual system. Each minute, the controller solves a deterministic, receding-horizon problem which seeks to minimize the cost of satisfying a given hydrogen demand, while using a storage tank to take advantage of time-varying electricity prices and photovoltaic inflow. We illustrate in simulation the significant cost reduction achieved by our method compared to others in the literature, and then validate our method by demonstrating it in real-time operation on the actual system. </pre>

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