Abstract
Chemical process plants often apply integration, or coupling between units, to enhance energy and raw material efficiency. This integration between units introduces interaction and may make the plant difficult to operate. This thesis studies how the control properties of plants are affected by integration. Integration topics that are considered are mass recycle, information integration between control levels and heat integration. This work presents procedures and new analysis tools that give a better evaluation of a plants inherent control properties. The gains from such an enhanced analysis are demonstrated through examples. Mass recycle in chemical reaction systems is investigated with respect to control quality. The multivariable effects of introducing recycle are described and analyzed with respect to interaction and disturbance rejection. Several purge actuator configurations are studied and it is shown how their fundamental difference in propagating secondary effects is important. The effect on the results of varying model detail is also studied. The integration of information between control levels is investigated with respect to interaction. Applied to cascade control in distillation the results show how controller tuning can be tailored to achieve one way interaction only. This work shows how a secondary control loop may alter the preferred choice of
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Citation Formats
Wolff, E A.
Studies on control of integrated plants.
Norway: N. p.,
1994.
Web.
Wolff, E A.
Studies on control of integrated plants.
Norway.
Wolff, E A.
1994.
"Studies on control of integrated plants."
Norway.
@misc{etde_10110666,
title = {Studies on control of integrated plants}
author = {Wolff, E A}
abstractNote = {Chemical process plants often apply integration, or coupling between units, to enhance energy and raw material efficiency. This integration between units introduces interaction and may make the plant difficult to operate. This thesis studies how the control properties of plants are affected by integration. Integration topics that are considered are mass recycle, information integration between control levels and heat integration. This work presents procedures and new analysis tools that give a better evaluation of a plants inherent control properties. The gains from such an enhanced analysis are demonstrated through examples. Mass recycle in chemical reaction systems is investigated with respect to control quality. The multivariable effects of introducing recycle are described and analyzed with respect to interaction and disturbance rejection. Several purge actuator configurations are studied and it is shown how their fundamental difference in propagating secondary effects is important. The effect on the results of varying model detail is also studied. The integration of information between control levels is investigated with respect to interaction. Applied to cascade control in distillation the results show how controller tuning can be tailored to achieve one way interaction only. This work shows how a secondary control loop may alter the preferred choice of quality control configuration. An integrated distillation design for separating ternary mixtures is given a comprehensive dynamic analysis for the first time. It is shown that utilization of all the available degrees of freedom for control is difficult. ``Holes`` in the operating range where fulfilling the specifications is impossible are described. Control solutions are presented and the design is compared to conventional ternary distillation schemes. 93 refs., 66 figs., 17 tabs.}
place = {Norway}
year = {1994}
month = {Jul}
}
title = {Studies on control of integrated plants}
author = {Wolff, E A}
abstractNote = {Chemical process plants often apply integration, or coupling between units, to enhance energy and raw material efficiency. This integration between units introduces interaction and may make the plant difficult to operate. This thesis studies how the control properties of plants are affected by integration. Integration topics that are considered are mass recycle, information integration between control levels and heat integration. This work presents procedures and new analysis tools that give a better evaluation of a plants inherent control properties. The gains from such an enhanced analysis are demonstrated through examples. Mass recycle in chemical reaction systems is investigated with respect to control quality. The multivariable effects of introducing recycle are described and analyzed with respect to interaction and disturbance rejection. Several purge actuator configurations are studied and it is shown how their fundamental difference in propagating secondary effects is important. The effect on the results of varying model detail is also studied. The integration of information between control levels is investigated with respect to interaction. Applied to cascade control in distillation the results show how controller tuning can be tailored to achieve one way interaction only. This work shows how a secondary control loop may alter the preferred choice of quality control configuration. An integrated distillation design for separating ternary mixtures is given a comprehensive dynamic analysis for the first time. It is shown that utilization of all the available degrees of freedom for control is difficult. ``Holes`` in the operating range where fulfilling the specifications is impossible are described. Control solutions are presented and the design is compared to conventional ternary distillation schemes. 93 refs., 66 figs., 17 tabs.}
place = {Norway}
year = {1994}
month = {Jul}
}