Feasibility assessment of data-driven modeling for a wastewater treatment process in Ceará

Abstract

The optimization of wastewater treatment plant (WWTP) operations is increasingly essential in the context of growing environmental demands, industrial variability, and regulatory tightening, particularly following the implementation of Brazil’s New Sanitation Legal Framework (Law No. 14,026/2020). Among the available treatment technologies, activated sludge processes stand out for their operational flexibility and efficiency in removing organic matter and nutrients. However, the inherent complexity and dynamic behavior of these systems pose significant challenges for real-time monitoring and control. In response to these challenges, this study proposes a data-driven modeling framework for an industrial activated sludge WWTP, aimed at predicting key performance indicators such as dissolved oxygen and sulfate concentration. The research utilizes real operational data and implements a suite of time series forecasting techniques, including ARIMA, SARIMAX, and multivariate regression models, combined with cross-validation strategies suitable for temporal data structures. A notable aspect of this study is the careful consideration of data quality limitations, which emerged due to inconsistencies and missing values naturally associated with the operational team’s decision-making. Rather than excluding these challenges, the study incorporates them as intrinsic to real-world industrial contexts and evaluates their impact on model performance. The results demonstrate the feasibility of applying data-driven models to enhance process observability and support operational decision-making in WWTPs, while also underscoring the importance of investing in data governance, operator training, and the gradual development of a data-driven operational culture. The study concludes with recommendations for improving data management practices and advancing the analytical maturity of wastewater treatment operations in line with national regulatory requirements and international best practices.