Adaptive nonisothermal computer control of a batch reactor

1983 ◽  
Vol 48 (2) ◽  
pp. 449-463
Author(s):  
František Jiráček ◽  
Josef Horák
Keyword(s):  
Heat Carrier ◽  
Control Method ◽  
Dynamic Properties ◽  
Batch Reactor ◽  
Computer Control ◽  
Exothermic Reaction ◽  
Cooling Capacity ◽  
Quality Of Control ◽  
Position Controller

The adaptive temperature control method of reaction mixture in a batch reactor with strongly exothermic reaction is verified experimentally. The utility degree of cooling capacity of the reactor is kept on the required value by use of a two-position controller which is changing the flow rate of heat carrier into the cooler. The method is based on continuous identification of properties of the system in actual time by use of the Hewlett-Packard 3 052 A computer centre. During the experiments temperature of mixture in the reactor and temperature of heat carrier in the cooler were measured. From the obtained data and their time derivatives reactivity of the mixture, heat transfer coefficient and utility degree of cooling capacity of the reactor were evaluated. In the experiments were studied the effects of cooler inertia and of additive noise in the temperature measurement on safety and quality of control. Experimental results have proved that the method is applicable to control of reaction temperature even under conditions when properties of the system are changing significantly e.g. reactivity of the mixture and dynamic properties of the manipulated variable and when pseudostationary states of the reactor are unstable in the open control loop. They simultaneously point to a significant effect of noise on system identification.

A simulation apparatus for the experimental study of batch reactor control methods

1986 ◽  
Vol 51 (6) ◽  
pp. 1259-1267
Author(s):  
Josef Horák ◽  
Petr Beránek
Keyword(s):  
Experimental Study ◽  
Closed Loop ◽  
Dynamic Properties ◽  
Batch Reactor ◽  
Exothermic Reaction ◽  
Electric Heating ◽  
Batch Reactors ◽  
Exchange Area ◽  
The Stability ◽  
Methods Of Control

A simulation apparatus for the experimental study of the methods of control of batch reactors is devised. In this apparatus, the production of heat by an exothermic reaction is replaced by electric heating controlled by a computer in a closed loop; the reactor is cooled with an external cooler whose dynamic properties can be varied while keeping the heat exchange area constant. The effect of the cooler geometry on its dynamic properties is investigated and the effect of the cooler inertia on the stability and safety of the on-off temperature control in the unstable pseudostationary state is examined.

A simplified method of temperature control maximizing productivity of the batch reactor; The effect of inertia of the cooling system

1982 ◽  
Vol 47 (2) ◽  
pp. 454-464 ◽  
Author(s):  
František Jiráček ◽  
Josef Horák
Keyword(s):  
Mathematical Model ◽  
Temperature Control ◽  
Cooling System ◽  
Batch Reactor ◽  
Exothermic Reaction ◽  
Cooling Capacity ◽  
Variable Activity ◽  
Simplified Method ◽  
Opening And Closing ◽  
Time Of Operation

The effect has been studied of the inertia of the cooling system on the reliability of control of the temperature of the reaction mixture. The study has been made using a mathematical model of the batch reactor with an exothermic reaction. The temperature has been controlled by a two-level controller opening and closing the flow of the coolant. The aim of the control has been to maintain a constant value of the degree of utilization of the cooling capacity of the reactor. The instantaneous value of the degree of utilization has been assessed from the ratio of times for which the cooling system is idle to the time of operation. The reliability of control has been studied for variable activity of the catalyst.

scholarly journals Methodology of Supervision by Analysis of Thermal Flux for Thermal Conduction of a Batch Chemical Reactor Equipped with a Monofluid Heating/Cooling System

2012 ◽  
Vol 2012 ◽  
pp. 1-10
Author(s):  
Ghania Henini ◽  
Fatiha Souahi ◽  
Ykhlef Laidani
Keyword(s):  
Thermal Conduction ◽  
Cooling System ◽  
Batch Reactor ◽  
Thermal Flux ◽  
Exothermic Reaction ◽  
Chemical Reactor ◽  
Thermal Control ◽  
Ride Quality ◽  
Heating And Cooling

We present the thermal behavior of a batch reactor to jacket equipped with a monofluid heating/cooling system. Heating and cooling are provided respectively by an electrical resistance and two plate heat exchangers. The control of the temperature of the reaction is based on the supervision system. This strategy of management of the thermal devices is based on the usage of the thermal flux as manipulated variable. The modulation of the monofluid temperature by acting on the heating power or on the opening degrees of an air-to-open valve that delivers the monofluid to heat exchanger. The study shows that the application of this method for the conduct of the pilot reactor gives good results in simulation and that taking into account the dynamics of the various apparatuses greatly improves ride quality of conduct. In addition thermal control of an exothermic reaction (mononitration) shows that the consideration of heat generated in the model representation improve the results by elimination any overshooting of the set-point temperature.

scholarly journals Digital medicine technologies for pre-trip medical examination of drivers

2020 ◽  
Vol 224 ◽  
pp. 03019
Author(s):  
O.V. Melnik ◽  
M.B. Nikiforov ◽  
V.V. Bonch-Bruevich ◽  
M.B. Kaplan ◽  
A.V. Shulyakov ◽  
...  
Keyword(s):  
Control System ◽  
Comparative Analysis ◽  
Computer Control ◽  
Control Panel ◽  
Diagnostic Efficiency ◽  
Computer Control System ◽  
Quality Of Control ◽  
Digital Medicine ◽  
Psychoemotional State

The technologies of automation of pre-trip integrated examination of the drivers’ conditions are considered, which make it possible to significantly improve the quality of control while reducing the time for its passage. A comparative analysis of known analogues is carried out, problems are formulated, the solution of which will increase the diagnostic efficiency of telemedicine examination. The configuration of the developed computer control system and the hardware-software structure of the subject’s control panel are described. The ways of increasing the reliability of user identification are considered. Technical means have been developed for non-contact thermometry and assessment of tremor parameters. Algorithms for assessing the physiological and psychoemotional state of drivers have been implemented.

Automation of selected brazes' dynamic properties in high-temperatures' measurement process

2013 ◽  
Vol 18 (2-3) ◽  
pp. 33-41
Author(s):  
Dominik Sankowski ◽  
Marcin Bakala ◽  
Rafał Wojciechowski
Keyword(s):  
Surface Tension ◽  
High Temperatures ◽  
Dynamic Properties ◽  
Automatic Measurement ◽  
Measurement Methodology ◽  
Joining Process ◽  
Wetting Force ◽  
Research Grant

Abstract The good quality of several manufactured components frequently depends on solidliquid interactions existing during processing. Nowadays, the research in material engineering focuses also on modern, automatic measurement methods of joining process properties, i.a. wetting force and surface tension, which allows for quantitative determination of above mentioned parameters. In the paper, the brazes’ dynamic properties in high-temperatures’ measurement methodology and the stand for automatic determination of braze’s properties, constructed and implmented within the research grant nr KBN N N519 441 839 - An integrated platform for automatic measurement of wettability and surface tension of solders at high temperatures, are widely described

METHODS ASSESSMENT QUALITY OF ACCOUNTING REPORTING AND MODELS OF THEIR MEASUREMENT

2020 ◽  
Vol 3 (3) ◽  
pp. 95-99
Author(s):  
E. H. ABU ◽  
Keyword(s):  
Internal Control ◽  
Stock Prices ◽  
Control Method ◽  
Financial Statements ◽  
Accounting Conservatism ◽  
Standardized Assessment ◽  
Accrual Quality ◽  
Indirect Measures

The article explores individual approaches used to measure and evaluate the quality of financial state-ments: standardized assessment, accrual-based models (accrual quality), Beneise models (M-Score), in-dexes - the internal control method and the degree of accounting conservatism. The reason for the great dependence on the use of indirect measures (proxies for the quality of financial statements or stock prices) is that some of the qualities of financial statements are unobservable.

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.

Quality Improvement of the DNA extracted by boiling method in Gram negative bacteria

2017 ◽  
Vol 6 (04) ◽  
pp. 5347 ◽  
Author(s):  
Omar B. Ahmed* ◽  
Anas S. Dablool
Keyword(s):  
Dna Extraction ◽  
Control Method ◽  
Extraction Procedure ◽  
Cost Effective ◽  
High Yield ◽  
Gram Negative Bacteria ◽  
Bacterial Dna ◽  
Gram Negative ◽  
E Coli

Several methods of Deoxyribonucleic acid (DNA) extraction have been applied to extract bacterial DNA. The amount and the quality of the DNA obtained for each one of those methods are variable. The study aimed to evaluate bacterial DNA extraction using conventional boiling method followed by alcohol precipitation. DNA extraction from Gram negative bacilli was extracted and precipitated using boiling method with further precipitation by ethanol. The extraction procedure performed using the boiling method resulted in high DNA yields for both E. coli and K. pneumoniae bacteria in (199.7 and 285.7μg/ml, respectively) which was close to control method (229.3 and 440.3μg/ml). It was concluded that after alcohol precipitation boiling procedure was easy, cost-effective, and applicable for high-yield quality of DNA in Gram-negative bacteria.

Intensification of cooling in a batch reactor with an exothermic reaction by nonisothermal control in stable pseudostationary states

1984 ◽  
Vol 49 (11) ◽  
pp. 2566-2578 ◽  
Author(s):  
Josef Horák ◽  
Petr Beránek ◽  
Dagmar Maršálková
Keyword(s):  
Batch Reactor ◽  
Exothermic Reaction ◽  
Reaction Model ◽  
Order Reaction ◽  
Zero Order ◽  
Coolant Temperature ◽  
Inlet Temperature ◽  
Adaptive Parameter ◽  
Zero Order Reaction ◽  
Set Up

An algorithm is set up and tested for the temperature control of a batch reactor consisting in jump changes in the inlet temperature of entering coolant. This temperature is so chosen that its difference from the temperature of the reaction mixture is near the highest difference at which the stable pseudostationary state of the system still exists. For the prediction of the new coolant inlet temperature, a zero-order reaction model is used with an adaptive parameter estimated from the experimentally established value of the maximum of the reaction mixture overheating at the previous coolant temperature.

Temperature control in a chemical reactor through variable area of the heat transfer surface. Experimental verification

1982 ◽  
Vol 47 (2) ◽  
pp. 446-453
Author(s):  
Josef Horák ◽  
František Jiráček ◽  
Libuše Ježová
Keyword(s):  
Batch Reactor ◽  
Exothermic Reaction ◽  
Chemical Reactor ◽  
Open Loop ◽  
Heat Transfer Surface ◽  
Laboratory Reactor ◽  
Hysteresis Control ◽  
Relay With Hysteresis ◽  
Rate Of Response ◽  
The Ideal

A possibility has been tested in the paper of the feed back control of temperature of the reaction mixture in a batch reactor with an exothermic reaction through the variable area of the cooling surface. The measurement were carried out in a laboratory reactor with a retractable cooler which was being immersed into the reaction mixture. The speed of motion of the cooler was sufficiently high permitting the process of immersion to be regarded as practically instantaneous. The aim of the control was to stabilize the set point temperature of the reaction mixture by a two-point controler. In dependence on the rate of response of the system to a change of the section variable either the ideal relay or the relay with hysteresis control algorithmus were used. The results of measurements showed that with the aid of a retractable cooler the temperature could be controlled safely even in those cases, in which the control by the variable flow rate of the coolant was unfeasible. The verification was carried out in the open-loop instable operating point of the reactor.

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