{"title":"Integrated enviro-economic optimization of solar-powered electrocoagulation for sustainable nitrate removal from groundwater","authors":"Benan Yazıcı Karabulut , Fatma Didem Alay , Fatma Zuhal Adalar","doi":"10.1016/j.jconhyd.2025.104745","DOIUrl":null,"url":null,"abstract":"<div><div>This study investigates the use of machine learning (ML) models—Linear Regression (LR), Support Vector Regression (SVR), Gradient Boosting (GB), K-Nearest Neighbour (KNN), Random Forest (RF), Artificial Neural Network (ANN), Multilayer Perceptron Regressor (MLPR), and Decision Tree (DT)—to optimize and predict energy consumption in the electrocoagulation (EC) process for nitrate (NO<sub>3</sub><sup>−</sup>) removal from groundwater. Alongside these data-driven approaches, Response Surface Methodology (RSM) with a Box-Behnken design (BBD) was applied to statistically evaluate the operational parameters. Among the tested models, the GB model showed the best performance with R<sup>2</sup> = 0.9924, Mean Squared Error (MSE) = 0.0135, Root Mean Squared Error (RMSE) = 0.1164 and Mean Absolute Percentage Error (MAPE) = 8.7418. Optimal operating conditions were identified to achieve NO<sub>3</sub><sup>−</sup> removal below permissible limits. The specific energy consumption under these conditions corresponds to operational costs of 0.46, 0.55, and 0.25 $/m<sup>3</sup> for Al, Fe, and Al/Fe combination electrodes, respectively. These results indicate that EC powered by photovoltaic energy (PV) can serve as a sustainable and decentralized solution for groundwater treatment in rural areas, offering both high removal efficiency and economically favourable operation.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"276 ","pages":"Article 104745"},"PeriodicalIF":4.4000,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of contaminant hydrology","FirstCategoryId":"93","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0169772225002505","RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
This study investigates the use of machine learning (ML) models—Linear Regression (LR), Support Vector Regression (SVR), Gradient Boosting (GB), K-Nearest Neighbour (KNN), Random Forest (RF), Artificial Neural Network (ANN), Multilayer Perceptron Regressor (MLPR), and Decision Tree (DT)—to optimize and predict energy consumption in the electrocoagulation (EC) process for nitrate (NO3−) removal from groundwater. Alongside these data-driven approaches, Response Surface Methodology (RSM) with a Box-Behnken design (BBD) was applied to statistically evaluate the operational parameters. Among the tested models, the GB model showed the best performance with R2 = 0.9924, Mean Squared Error (MSE) = 0.0135, Root Mean Squared Error (RMSE) = 0.1164 and Mean Absolute Percentage Error (MAPE) = 8.7418. Optimal operating conditions were identified to achieve NO3− removal below permissible limits. The specific energy consumption under these conditions corresponds to operational costs of 0.46, 0.55, and 0.25 $/m3 for Al, Fe, and Al/Fe combination electrodes, respectively. These results indicate that EC powered by photovoltaic energy (PV) can serve as a sustainable and decentralized solution for groundwater treatment in rural areas, offering both high removal efficiency and economically favourable operation.
期刊介绍:
The Journal of Contaminant Hydrology is an international journal publishing scientific articles pertaining to the contamination of subsurface water resources. Emphasis is placed on investigations of the physical, chemical, and biological processes influencing the behavior and fate of organic and inorganic contaminants in the unsaturated (vadose) and saturated (groundwater) zones, as well as at groundwater-surface water interfaces. The ecological impacts of contaminants transported both from and to aquifers are of interest. Articles on contamination of surface water only, without a link to groundwater, are out of the scope. Broad latitude is allowed in identifying contaminants of interest, and include legacy and emerging pollutants, nutrients, nanoparticles, pathogenic microorganisms (e.g., bacteria, viruses, protozoa), microplastics, and various constituents associated with energy production (e.g., methane, carbon dioxide, hydrogen sulfide).
The journal''s scope embraces a wide range of topics including: experimental investigations of contaminant sorption, diffusion, transformation, volatilization and transport in the surface and subsurface; characterization of soil and aquifer properties only as they influence contaminant behavior; development and testing of mathematical models of contaminant behaviour; innovative techniques for restoration of contaminated sites; development of new tools or techniques for monitoring the extent of soil and groundwater contamination; transformation of contaminants in the hyporheic zone; effects of contaminants traversing the hyporheic zone on surface water and groundwater ecosystems; subsurface carbon sequestration and/or turnover; and migration of fluids associated with energy production into groundwater.