Forecasting Copper Electrorefining Cathode Rejection by Means of Recurrent Neural Networks With Attention Mechanism
Electrolytic refining is the last step of pyrometallurgical copper production. Here, smelted copper is converted into high-quality cathodes through electrolysis. Cathodes that do not meet the physical quality standards are rejected and further reprocessed or sold at a minimum profit. Prediction of c...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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IEEE
2021-01-01
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| Series: | IEEE Access |
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| Online Access: | https://ieeexplore.ieee.org/document/9410222/ |
| _version_ | 1830272431870181376 |
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| author | Pedro Pablo Correa Aldo Cipriano Felipe Nunez Juan Carlos Salas Hans Lobel |
| author_facet | Pedro Pablo Correa Aldo Cipriano Felipe Nunez Juan Carlos Salas Hans Lobel |
| author_sort | Pedro Pablo Correa |
| collection | DOAJ |
| description | Electrolytic refining is the last step of pyrometallurgical copper production. Here, smelted copper is converted into high-quality cathodes through electrolysis. Cathodes that do not meet the physical quality standards are rejected and further reprocessed or sold at a minimum profit. Prediction of cathodic rejection is therefore of utmost importance to accurately forecast the electrorefining cycle economic production. Several attempts have been made to estimate this process outcomes, mostly based on physical models of the underlying electrochemical reactions. However, they do not stand the complexity of real operations. Data-driven methods, such as deep learning, allow modeling complex non-linear processes by learning representations directly from the data. We study the use of several recurrent neural network models to estimate the cathodic rejection of a cathodic cycle, using a series of operational measurements throughout the process. We provide an ARMAX model as a benchmark. Basic recurrent neural network models are analyzed first: a vanilla RNN and an LSTM model provide an initial approach. These are further composed into an Encoder-Decoder model, that uses an attention mechanism to selectively weight the input steps that provide most information upon inference. This model obtains 5.45% relative error, improving by 81.4% the proposed benchmark. Finally, we study the attention mechanism’s output to distinguish the most relevant electrorefining process steps. We identify the initial state as critical in predicting cathodic rejection. This information can be used as an input for decision support systems or control strategies to reduce cathodic rejection and improve electrolytic refining’s profitability. |
| first_indexed | 2024-12-18T23:23:59Z |
| format | Article |
| id | doaj.art-610c7ed2952149b3816d3408d4cfa1da |
| institution | Directory Open Access Journal |
| issn | 2169-3536 |
| language | English |
| last_indexed | 2024-12-18T23:23:59Z |
| publishDate | 2021-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Access |
| spelling | doaj.art-610c7ed2952149b3816d3408d4cfa1da2022-12-21T20:47:52ZengIEEEIEEE Access2169-35362021-01-019790807908810.1109/ACCESS.2021.30747809410222Forecasting Copper Electrorefining Cathode Rejection by Means of Recurrent Neural Networks With Attention MechanismPedro Pablo Correa0https://orcid.org/0000-0001-9965-0553Aldo Cipriano1https://orcid.org/0000-0002-6516-9646Felipe Nunez2https://orcid.org/0000-0002-8741-717XJuan Carlos Salas3https://orcid.org/0000-0001-7674-6376Hans Lobel4https://orcid.org/0000-0003-3514-9414Department of Computer Science, Pontificia Universidad Católica de Chile, Santiago, ChileDepartment of Electrical Engineering, Pontificia Universidad Católica de Chile, Santiago, ChileDepartment of Electrical Engineering, Pontificia Universidad Católica de Chile, Santiago, ChileDepartment of Mining Engineering, Pontificia Universidad Católica de Chile, Santiago, ChileDepartment of Computer Science, Pontificia Universidad Católica de Chile, Santiago, ChileElectrolytic refining is the last step of pyrometallurgical copper production. Here, smelted copper is converted into high-quality cathodes through electrolysis. Cathodes that do not meet the physical quality standards are rejected and further reprocessed or sold at a minimum profit. Prediction of cathodic rejection is therefore of utmost importance to accurately forecast the electrorefining cycle economic production. Several attempts have been made to estimate this process outcomes, mostly based on physical models of the underlying electrochemical reactions. However, they do not stand the complexity of real operations. Data-driven methods, such as deep learning, allow modeling complex non-linear processes by learning representations directly from the data. We study the use of several recurrent neural network models to estimate the cathodic rejection of a cathodic cycle, using a series of operational measurements throughout the process. We provide an ARMAX model as a benchmark. Basic recurrent neural network models are analyzed first: a vanilla RNN and an LSTM model provide an initial approach. These are further composed into an Encoder-Decoder model, that uses an attention mechanism to selectively weight the input steps that provide most information upon inference. This model obtains 5.45% relative error, improving by 81.4% the proposed benchmark. Finally, we study the attention mechanism’s output to distinguish the most relevant electrorefining process steps. We identify the initial state as critical in predicting cathodic rejection. This information can be used as an input for decision support systems or control strategies to reduce cathodic rejection and improve electrolytic refining’s profitability.https://ieeexplore.ieee.org/document/9410222/Deep learningelectrorefiningpredictive modelsrecurrent neural networks |
| spellingShingle | Pedro Pablo Correa Aldo Cipriano Felipe Nunez Juan Carlos Salas Hans Lobel Forecasting Copper Electrorefining Cathode Rejection by Means of Recurrent Neural Networks With Attention Mechanism IEEE Access Deep learning electrorefining predictive models recurrent neural networks |
| title | Forecasting Copper Electrorefining Cathode Rejection by Means of Recurrent Neural Networks With Attention Mechanism |
| title_full | Forecasting Copper Electrorefining Cathode Rejection by Means of Recurrent Neural Networks With Attention Mechanism |
| title_fullStr | Forecasting Copper Electrorefining Cathode Rejection by Means of Recurrent Neural Networks With Attention Mechanism |
| title_full_unstemmed | Forecasting Copper Electrorefining Cathode Rejection by Means of Recurrent Neural Networks With Attention Mechanism |
| title_short | Forecasting Copper Electrorefining Cathode Rejection by Means of Recurrent Neural Networks With Attention Mechanism |
| title_sort | forecasting copper electrorefining cathode rejection by means of recurrent neural networks with attention mechanism |
| topic | Deep learning electrorefining predictive models recurrent neural networks |
| url | https://ieeexplore.ieee.org/document/9410222/ |
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