Energy-efficient process for treating dilute organic wastewater from ship washing using heat integrated catalytic cracking oxidation and distillation technologies

Dilute organic wastewater is a common challenge in the chemical and petroleum industries due to its complexity and low organic concentration, making the recovery of valuable components both difficult and energy-intensive. In ship-washing operations, where chemicals are cleaned from tanks before loading new cargo, several streams of dilute wastewater with simple and sole organic component are generated. Efficient treatment of such wastewater is both urgent and necessary. This work reports an energy-efficient process that integrates distillation with catalytic cracking oxidation for the cost-effective treatment of dilute organic wastewater. The distillation unit concentrates the organic components, while the catalytic cracking oxidation breaks down large molecules into small ones, which are subsequently oxidized into carbon dioxide and water. The process achieves competitive net energy performance through effective heat integration, making it a promising solution for industrial applications. Several case studies simulated by using Aspen Plus V14 are employed to demonstrate the effectiveness and economic advantages of the reported process. • Energy-efficient process proposed for dilute organic wastewater treatment. • Heat-integrated distillation and oxidation improves treatment cost-efficiency. • Proper feed organic composition enables neat heat integration and energy saving. • The process suitable for systems where organic components are more volatile than water.