Development of an integrated network for waste-to-energy and central utility systems considering air pollutant emissions pinch analysis

摘要

This study aims to integrate central utility systems in a large petrochemical industry with adjoining waste-to-energy networks to form an eco-friendly energy management system. The waste-to-energy networks studied in this contribution include the following main systems: (1) wastewater treatment plants for biogas production, (2) a biogas upgrading process for biomethane generation, and (3) a molten carbonate fuel cell together with a Rankine cycle to harness green electricity. Waste streams in the proposed model consist of wastewater from wastewater treatment plants and waste steam from central utility systems itself. The derived green electricity is utilized to satisfy the energy demands in central utility systems. A waste-to-energy network is simulated by simulation tools, and a mixed integer linear programming problem is formulated to optimize central utility systems based on the simulation results. A case study of the Yeosu petrochemical industrial complex in South Korea evaluates the developed model. The total economic costs of the optimized central utility systems based on the integrated model are reduced by approximately 15% compared to the existing central utility systems. The results from air pollutant emissions pinch analysis indicate that the total quantities of carbon dioxides and sulfur oxides emitted from the integrated model are decreased by about 35%. The feasibility of combining the two networks is demonstrated from environmental and economic points of view. (C) 2019 Elsevier Ltd. All rights reserved.