New Framework Balances Water Conservation and Carbon Reduction in Chinese Industry

A new research framework addresses the critical challenge facing China's industrial sector of balancing water conservation, carbon emission reduction, and aquatic ecosystem preservation at manageable costs. Yuehong Zhao and Hongbin Cao from the Institute of Process Engineering of Chinese Academy of Sciences developed this mechanism-data dual-driven approach that combines hybrid modeling with superstructure optimization to solve the water-carbon-economy nexus problem.

The framework involves developing hybrid models that characterize water-use and treatment processes along with their associated carbon emissions. By integrating mechanistic understanding with data-driven techniques, these models enhance interpretability and generalization even with limited training datasets. According to Zhao, the lead author of the study published in Water & Ecology, solving the optimization model identifies the optimal technical pathway for simultaneous water conservation and carbon emission reduction at minimum water-use cost. The research provides valuable information to support decision-making about water network optimization within industrial parks.

The hybrid modeling approach builds on deep understanding of mechanisms underlying typical water-use, wastewater treatment and reuse processes within industrial parks. Cao notes that this represents an effective approach to promoting the application of machine learning and AI technologies in the industrial sector, though systematic theory and methodology for hybrid modeling remain underdeveloped. The key challenges include selecting appropriate mechanisms and their expression for integration with machine learning.

A superstructure optimization model was constructed based on unit models and domain knowledge, encompassing feasible unit technologies, their interconnections, and relevant constraints to identify optimal solutions. Deterministic optimization algorithms were applied to achieve global optimum solutions with minimal water-use cost. In case studies, a multi-scale optimization methodology for water conservation in industrial parks was established, leading to the development of a practical software tool successfully applied in steel companies. The framework can provide solutions that balance local and overall benefits, as well as economic benefits and environmental impacts. The research was supported by a grant from the key Program of National Natural Science Foundation of China (51934006) and the findings are detailed in the study available at https://doi.org/10.1016/j.wateco.2025.100003.