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Main Authors:	Toledo-Zucco, Jesus-Pablo, Sbarbaro, Daniel, Silva Jr, Joao Manoel Gomes da
Format:	Preprint
Published:	2023
Subjects:	Systems and Control
Online Access:	https://arxiv.org/abs/2305.18605
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author	Toledo-Zucco, Jesus-Pablo Sbarbaro, Daniel Silva Jr, Joao Manoel Gomes da
author_facet	Toledo-Zucco, Jesus-Pablo Sbarbaro, Daniel Silva Jr, Joao Manoel Gomes da
contents	Sedimentation is a crucial phenomenon in recovering water from slurries by separating solid-liquid. Thickeners and sedimentation columns are equipments widely used in the process industry to reclaim water from process slurries. This contribution addresses the problem of controlling the turbidity of the recovered water in a sedimentation column by manipulating the underflow. The phenomenological model describing the turbidity is too complex to be used in a control strategy, and it is difficult to identify its parameters using plant measurements. This work proposes an empirical piece-wise time-delay model for modeling the turbidity at the top of the column to circumvent these problems. A systematic design procedure is developed to tune a Proportional Integral controller guaranteeing closed-loop stability for systems modeled as a piece-wise time delay model. Experiments in a pilot plant validate the theoretical results and illustrate the control performance under various operational scenarios.
format	Preprint
id	arxiv_https___arxiv_org_abs_2305_18605
institution	arXiv
publishDate	2023
record_format	arxiv
spellingShingle	Turbidity Control in Sedimentation Columns by Direction Dependent Models Toledo-Zucco, Jesus-Pablo Sbarbaro, Daniel Silva Jr, Joao Manoel Gomes da Systems and Control Sedimentation is a crucial phenomenon in recovering water from slurries by separating solid-liquid. Thickeners and sedimentation columns are equipments widely used in the process industry to reclaim water from process slurries. This contribution addresses the problem of controlling the turbidity of the recovered water in a sedimentation column by manipulating the underflow. The phenomenological model describing the turbidity is too complex to be used in a control strategy, and it is difficult to identify its parameters using plant measurements. This work proposes an empirical piece-wise time-delay model for modeling the turbidity at the top of the column to circumvent these problems. A systematic design procedure is developed to tune a Proportional Integral controller guaranteeing closed-loop stability for systems modeled as a piece-wise time delay model. Experiments in a pilot plant validate the theoretical results and illustrate the control performance under various operational scenarios.
title	Turbidity Control in Sedimentation Columns by Direction Dependent Models
topic	Systems and Control
url	https://arxiv.org/abs/2305.18605

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