TEMPERATURE MODE MANAGEMENT OF CHEMICAL REACTOR

A chemical reactor is one of the common apparatuses in chemical industry. Despite a large number of the works related to automation and control of chemical reactors, the problem of synthesizing control systems that provide the maintenance of optimal modes of their operation remains practically unsolved. This is related to the principal feature of chemical reactors as controlled objects, namely, manifold, non-linearity, and multi-coupling. An outcome from this situation is to develop a physical theory of control, in particular synergetic control theory. The problem of analytical synthesis of nonlinear control law of the chemical reactor temperature regime has been solved. We use the methods of synergetic control theory, simulation methods and methods of computational experiment. The paper deals with continuous stirred tank reactor equipped with a mechanical stirrer and cooling jacket. The reactor operates in the polytropic mode. The multistep series-parallel exothermic process is carried out in the reactor. The objective of chemical reactor operation is to obtain the key product of specified concentration. Using the analytical design method of aggregated regulators, a non-linear control algorithm was synthesized, which solves the problem of stabilization of reaction mixture temperature in the apparatus under the action of disturbances on the object. Computer simulation of the object–regulator isolated system showed such properties of synthesized control system as the disturbance invariance, covariance to the given actions, and asymptotic stability.

Download Full-text

THE CONTROL ALGORITHM FOR CONCENTRATION OF THE TARGET PRODUCT IN THE CHEMICAL REACTOR

Automation and modeling in design and management of ◽

10.30987/article_5c387d62698a75.92047422 ◽

2019 ◽

Vol 2018 (2) ◽

pp. 34-40 ◽

Cited By ~ 1

Author(s):

Александр Лабутин ◽

Aleksandr Labutin ◽

Владимир Невиницын ◽

Vladimir Nevinitsyn ◽

Галина Волкова ◽

...

Keyword(s):

Control Theory ◽

Chemical Reactor ◽

Target Component ◽

Continuous Stirred Tank Reactor ◽

Chemical Reactors ◽

Synergetic Control Theory ◽

Automation And Control ◽

Synergetic Control ◽

And Control ◽

Nonlinear Control Law

A chemicalreactor is one of the common apparatuses in chemical industry. Despite a large number of theworks related to automation and control of chemical reactors, the problem of synthesizing controlsystems that provide the maintenance of optimal modes of their operation remains practically unsolved.This is related to the principal feature of chemical reactors as controlled objects, namely,manifold, non-linearity, and multi-coupling. An outcome from this situation is to develop a physicaltheory of control, in particular synergetic control theory. The problem of analytical synthesis of nonlinear control law for the concentration of the target component in a chemical reactor has been solved.We use the methods of synergetic control theory, simulation methodsand methods of computational experiment. The paper deals with continuous stirred tank reactor equipped with a mechanicalstirrer and cooling jacket. The reactor operates in the polytropic mode. The multistep series-parallelexothermic process is carried out in the reactor. The objective of chemical reactor operationis to obtain the key product of specified concentration.

Download Full-text

SYNTHESIS OF CHEMICAL REACTOR NONLINEAR CONTROL ALGORITHM USING SYNERGETIC APPROACH

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/tcct.2017602.5479 ◽

2017 ◽

Vol 60 (2) ◽

pp. 38 ◽

Cited By ~ 1

Author(s):

Alexander N. Labutin ◽

Vladimir Yu. Nevinitsyn

Keyword(s):

Control System ◽

Control Theory ◽

Control Algorithm ◽

Design Method ◽

Chemical Reactor ◽

Chemical Reactors ◽

Analytical Design ◽

Synergetic Control Theory ◽

Synergetic Control ◽

The Given

The problem of analytical synthesis of synergetic control system of chemical reactor for realization of a complex series–parallel exothermal reaction has been solved. The synthesis of control principles is performed using the analytical design method of aggregated regulators. A chemical reactor is one of the common apparatuses in chemical industry. Despite a large number of the works related to automation and control of chemical reactors, the problem of synthesizing control systems that provide the maintenance of optimal modes of their operation remains practically unsolved. This is related to the principal feature of chemical reactors as controlled objects, namely, manifold, non-linearity, and multi-coupling. An outcome from this situation is to develop a physical theory of control, in particular synergetic control theory. The use of synergism ideas in the problems of control assumes the development and realization of a method of directed target self-organization of dissipative non-linear systems “object-regulator”. Furthermore, the aim of the motion of a system is formulated as the desired invariant manifold in a phase space of the object, which acts as a target attractor. The paper deals with continuous stirred tank reactor equipped with a mechanical stirrer and cooling jacket. The reactor operates in the polytropic mode. The multistep series-parallel exothermic process is carried out in the reactor. The objective of chemical reactor operation is to obtain the key product of specified concentration. The aim of chemical reactor control system is to maintain both concentration of desired product and temperature of reaction mixture in the device at the given values under the action of disturbances on the object. Using the analytical design method of aggregated regulators on the basis of parallel-series combination of invariant manifolds, a non-linear control algorithm was synthesized, which solves the problem of stabilization of the concentration of the target component and mixture temperature. Computer simulation of the object–regulator isolated system confirmed these properties of synthesized control system as the disturbance invariance, covariance to the given actions, and asymptotic stability. These facts make synergetic control theory very promising for application for such complex, manifold, and nonlinear objects of chemical engineering as chemical reactors. For citation:Labutin A.N., Nevinitsyn V.Yu. Synthesis of chemical reactor nonlinear control algorithm using synergetic approach.Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N2. P. 38-44.

Download Full-text

ROBUST CONCENTRATION CONTROL OF TARGET PRODUCT IN CHEMICAL REACTOR

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/ivkkt.20186112.5914 ◽

2018 ◽

Vol 61 (12) ◽

pp. 129-136 ◽

Cited By ~ 1

Author(s):

Alexander. N. Labutin ◽

Vladimir Yu. Nevinitsyn ◽

Viktor A. Zaytsev ◽

Galina V. Volkova

Keyword(s):

Control System ◽

Control Theory ◽

Control Algorithm ◽

Chemical Reactor ◽

Control Law ◽

Target Product ◽

Synergetic Control Theory ◽

Non Linear ◽

Synergetic Control ◽

The Given

A liquid-phase continuous stirred tank reactor equipped with a mechanical stirrer and cooling jacket is considered as a control object. The reactor operates in the polytropic mode. The multistep series-parallel exothermic process is carried out in the reactor. The objective of chemical reactor operation is to obtain the key product of specified concentration. The paper deals with analytical synthesis of automatic concentration control system of target product which provides invariance, covariance to the given actions, asymptotic stability and robustness under the action of uncontrollable parametric and signal disturbances. The astatic control law obtained using the synergetic control theory is proposed. Using the method of analytical design of aggregated regulators (ADAR) for a given invariant manifold, a non-linear control algorithm with an integral part was synthesized which solves the problem of stabilization of the concentration of target component on the exit of the reactor at the given value under the action of disturbances on the object. Algorithmic synthesis of the control law is carried out using a non-linear mathematical model of the object without the use of the linearization procedure. As a result of simulation it was found that the closed-loop control system has no static control error under the action of uncontrollable parametric and signal disturbances on the object, changes in the set points and initial deviation of the state variables from the static values. Consequently, the proposed non-linear concentration control algorithm has the property of robustness. The obtained results indicate the effectiveness of the ADAR method and the prospects of the synergetic control theory for solving problems of algorithmic synthesis of control systems of non-linear, multi-dimensional and multi-connected technological objects. The integration of the synthesized control law of chemical reactor at the design stage will allow implementing flexible cybernetically organized chemical-technological systems.

Download Full-text

Synthesis of the cascade control system of the thermal regime of a technological object by the methods of synergetic control theory

Vestnik IGEU ◽

10.17588/2072-2672.2019.3.041-048 ◽

2019 ◽

pp. 41-48

Author(s):

A.N. Labutin ◽

V.Yu. Nevinitsyn ◽

G.V. Volkova ◽

A.V. Panasenkova ◽

V.A. Zaytsev

Keyword(s):

Control System ◽

Control Theory ◽

Automatic Control ◽

Thermal Regime ◽

Parametric Uncertainty ◽

Chemical Reactor ◽

Synergetic Control Theory ◽

Technological Object ◽

Synergetic Control ◽

Algorithmic Structure

The paper considers technological control objects whose physical properties, state of aggregation and composition are changed by hydromechanical, physical and chemical effects on the flows of initial substances. The main feature of such objects is their multi-dimensionality, nonlinearity, multiconnectivity, and parametric uncertainty of the mathematical model at the design stage. One of such objects is the chemical reactor with the thermal regime predominantly controlled by single-loop or cascade automatic control systems based on linear algorithms. The main disadvantage of such systems is the problem of maintaining robustness, i.e. stability and control quality under the action of parametric disturbances. In our opinion, the method of analytical design of aggregated regulators (ADAR), developed within the framework of the synergetic control theory, is promising in this sense. The research uses methods of system analysis of technological processes as control objects, methods of the automatic control theory and analytical synthesis of control algorithms based on the synergetic control theory and computer simulation methods. Using the ADAR method, we have solved the problem of algorithmic synthesis of the cascade-coupled control system of the thermal regime of a technological object (chemical reactor) in the nonlinear formulation applying a nonlinear mathematical model of the object. Computer simulation methods have proved the functionality of the «object – control subsystem» complex: system stability, covariance with the set point. It is shown that in the systems controlling thermal processes of the considered type, the heat transfer coefficient parametric uncertainty can lead to an excessive value of the static error, which means that the algorithmic structure of the automatic control system has to be improved. To ensure full robustness of the automatic control system, it is recommended to make the system’s algorithmic structure more complex by introducing an astatic component into the control law and correcting the algorithm tuning parameters.

Download Full-text