Polyvinyl chloride (PVC) is one of the most widely used polymers due to its physical properties and versatility. Water consumption of the suspension method is a critical issue that hinders competitiveness. In that case, this study implements water integration through direct recycling, with the aim of minimizing both freshwater consumption and wastewater generation. The source–sink diagram was used to generate the recycled water network, and the integrated process was simulated using software. From simulation data, the water–energy–product (WEP) analysis method was used to assess the process performance, and sustainability indicators for water, energy, and product were evaluated. Fractional water consumption and wastewater production ratio indicators increased to 51.1% and 55.0%, compared to 41% and 54% in the non-integrated process, showing improved water efficiency and cost reduction. The unreacted material reuse index reached 100%, while the production yield was 99.8%, due to effective recycling of unreacted VCM. The use of natural gas and energy integration led to optimal performance in TCE, NGCI, and EECI indicators. However, the ESI indicator was high (3.59 MJ/t) due to energy demands from thermal control equipment for water recirculation.

Polyvinyl chloride (PVC) remains one of the most widely used synthetic polymers worldwide, primarily due to its versatility, cost-effectiveness, and broad applicability across construction, healthcare, automotive, and consumer goods industries. However, its production involves hazardous chemicals, particularly vinyl chloride monomer (VCM), which requires rigorous safety assessments. In this context, the present study applies the Inherent Safety Index (ISI) methodology to evaluate the safety performance of a suspension polymerization process for PVC production that incorporates direct water recycling as a sustainability measure. The integration of water reuse reduces the fractional water consumption index from 2.8 to 2.2 and achieves a recovered water purity of 99.6%, demonstrating clear environmental benefits in terms of resource conservation. Beyond water savings, the core objective is to assess how this integration influences the inherent risks associated with the process. The key operational stages—polymerization, VCM recovery, product purification, and water recirculation—were modeled and analyzed using computer-aided process engineering (CAPE) tools. The ISI analysis yielded a score of 33, surpassing the threshold typically associated with inherently safer designs, with VCM hazards alone contributing a score of 19 due to its high flammability and carcinogenicity. These findings reveal a critical trade-off between environmental performance and inherent safety, underscoring that resource integration measures, while beneficial for sustainability, may require complementary safety improvements. This study highlights the necessity of incorporating inherently safer design principles alongside process integration strategies to achieve balanced progress in operational efficiency, environmental responsibility, and risk minimization in PVC manufacturing.

Over the past decades, global plastic demand has steadily increased due to the favorable physicochemical properties of these materials, including low weight, durability, versatility, and low production cost. Among synthetic polymers, polyvinyl chloride (PVC) is one of the most widely produced, accounting for approximately 10% of global polymer production. Suspension polymerization is commonly used for its manufacture because of its high productivity and suitable operational control; however, this process is associated with considerable energy consumption and emissions with potential environmental impacts. In this work, the Waste Reduction (WAR) Algorithm was applied to evaluate the environmental performance of a PVC production process with mass integration and direct water recycling. The Potential Environmental Impact (PEI) was quantified under four scenarios, considering both generation and output rates, as well as different fuel sources. The results showed that the environmental performance of the system strongly depends on the selected system boundaries and on the incorporation of energy-related effects. Under the gate-to-gate scope considered, some scenarios exhibited negative net PEI generation values, indicating that the PEI associated with the outlet streams was lower than that of the inlet streams within the modeled system. However, when energy consumption was included, it became the main contributor to total PEI, reaching 2560 and 3070 PEI/day in Cases 3 and 4, respectively. The toxicological assessment showed that ATP was the only category with positive PEI generation, while natural gas presented the lowest potential environmental impact among the energy sources evaluated. Overall, the process showed comparatively favorable environmental performance within the assumptions and methodological boundaries of the WAR analysis.

The suspension polyvinyl chloride (PVC) industry is characterized by intensive water and energy consumption, making process integration an attractive strategy for improving resource efficiency. Previous studies have demonstrated the technical, environmental, and safety benefits of direct water recycling in suspension PVC production; however, the thermodynamic implications of this integration have not been evaluated. Therefore, this study presents an exergy-based sustainability assessment of an industrial-scale suspension PVC production process incorporating direct water recycling through mass integration using a Computer-Aided Process Engineering (CAPE) approach implemented in Aspen Plus^®. Physical and chemical exergy were calculated for all material and utility streams under pseudo-steady-state conditions, and exergy balances were performed for the main process sections to determine exergy destruction and exergetic efficiency. The integrated configuration achieved an aggregated stage-level exergetic efficiency of 93.0%, representing a 16.8% improvement over the conventional process, while freshwater consumption and wastewater generation were reduced by 16.0% and 26.3%, respectively. Recovery and purification accounted for the largest share of total exergy destruction (39.2% and 36.4%), indicating that downstream separation operations dominate the thermodynamic inefficiencies of the process. Although direct water recycling introduced additional local irreversibilities associated with recycle operations, the integrated configuration improved the utilization of available exergy while reducing water consumption and wastewater discharge. These results demonstrate that exergy analysis provides complementary information beyond conventional water–energy–product indicators and constitutes an effective tool for identifying thermodynamic improvement opportunities in industrial PVC production systems.