Prediction of Solvent Component and Composition for Absorption-Based Acid Gas Removal Unit using Optuna-LightGBM and K-means
Rafi Jusar WISHNUWARDANA, Madiah OMAR, Haslinda ZABIRI, Kishore BINGI, Rosdiazli IBRAHIM
Abstract. Acid gas removal unit (AGRU) is a pivotal component of a natural gas processing plant. The primary purpose of acid gas removal is to reach the industrial pipeline standard of H2S below four ppm and CO2 below 2% per volume for pipeline quality. The most widely used technique is an absorption-based AGRU using amine as a solvent. MDEA is the most utilized solvent but has the drawback of absorbing CO2. The mixture of other amine and physical solvents is necessary to assist the absorption of CO2. However, the main problem of mixing solvents is parameter complexity. The machine learning method is utilized to find the most optimal solvent based on its operational parameters. LightGBM tuned with Optuna are used to classify the solvent component, followed by K-means to identify solvent composition. The algorithm is applied to six different solvent blends and two feed gas compositions, resulting in 37,786 data points. The LightGBM model tuned with Optuna performed excellently with accuracy of 0.98 and training time under 0.2 seconds. K-means showed the silhouette score averaging 0.5, showing that the data is not well clustered. This model demonstrates reliable capability in analyzing and distinguishing the solvent component and its respective composition.
Keywords
Acid Gas Removal Unit, Solvent Component, Solvent Composition, LightGBM, Optuna, K-Means
Published online 1/15/2026, 8 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Rafi Jusar WISHNUWARDANA, Madiah OMAR, Haslinda ZABIRI, Kishore BINGI, Rosdiazli IBRAHIM, Prediction of Solvent Component and Composition for Absorption-Based Acid Gas Removal Unit using Optuna-LightGBM and K-means, Materials Research Proceedings, Vol. 59, pp 162-169, 2026
DOI: https://doi.org/10.21741/9781644903957-21
The article was published as article 21 of the book Separation Technology
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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