Universal low-carbon strategy for deep-resourcilization of industrial oily sludges

The economic and environmental treatment of oily sludges is always a challenge in industry. Herein, we propose an interfacial capture and demulsification hybrid process to deeply separate and recover the heavy oil (even over 97%) from the sludges with rejecting the encapsulated micro-/nano-mineral particles from the heavy oil phase in a low-carbon way (save energy over 69.3% compared with commercial pyrolysis). After testing over ten different oily sludges samples from petroleum industry, coal industry and steel industry, it is proved that this novel process possesses good universality, as well as high quality of products (oil, solids and water). A detailed mechanistic study by interfacial/surface characterizations approves the roles of interfacial capture of fine particles by dispersed water droplets and demulsification of asphaltenes-solids co-stabilized emulsions by a home-made oxygen-containing non-ionic demulsifier. Finally, a comprehensive evaluation has been made for this process, which demonstrates its excellent economy and environmental feasibility.