Feasibility Study of a Thermal Desalination Plant (MED) in the Styrene Production Process

This article shows the application of sensible waste heat (liquid phase) driven multi-effect distillation (MED) technology to use waste heat sources commonly abundant in the chemical industries. The case study of is the styrene production plant. Styrene (Vinylbenzene) is a colorless liquid used as a monomer for polymer compounds. The primary production of styrene is used for producing polystyrene with applications in various fields such as electronics, plastic, and the packaging industry. The low-grade sensible waste heat of this process can be used as a heat source of a desalination plant to reduce a significant amount of the MED operating costs, which is related to the production of steam for the heat source. After identifying the waste heat flow of this process, the water flow output from a decanter, to check the profitability potential of this plant, economic analyzes were performed to calculate the investment (CAPEX) and operating (OPEX) costs. Finally, the project's net present value (NPV) and the internal rate of return (IRR) have been calculated by Microsoft Excel software