Research Progress on Thermal Regeneration Technology for Saturated Activated Carbon
Activated carbon, characterized by its extensive pore structure, high specific surface area, and superior adsorption capacity, is widely employed in advanced water treatment. However, upon reaching adsorption saturation, its efficacy diminishes, necessitating replacement or regeneration. Thermal regeneration stands out due to its high desorption efficiency, simple equipment requirements, and low energy consumption, making it the predominant industrial method. Despite its prevalence, systematic investigations into the underlying reaction mechanisms and the influence of operational parameters remain insufficient. This review comprehensively examines common thermal regeneration technologies for saturated activated carbon, including multi-hearth furnaces, rotary kilns, superheated steam, microwave, and solar regeneration. It delineates the fundamental principles, process flows, advantages, disadvantages, and current research status of each method. The desorption and reaction mechanisms of pollutants within activated carbon pores during thermal regeneration are discussed in detail, along with the effects of critical conditions such as temperature, atmosphere, and purge gas flow rate on pollutant removal efficiency. Furthermore, the relationship between activated carbon performance parameters and regeneration efficiency is analyzed, and innovations based on conventional thermal regeneration, as well as integration with emerging technologies, are explored. Finally, the challenges facing thermal regeneration are summarized, and future research priorities are proposed, focusing on the treatment of waste gas and liquid byproducts, technology integration, and enhancement of overall regeneration performance. This review aims to provide a scientific foundation for the sustainable recycling of activated carbon in industrial applications.