(71c) Wet Oxidation as Applied to Powdered Activated Carbon Recovery in Wastewater Treatment

Zimpro® wet oxidation has long been used to destroy organics and sulfidic material in industrial wastes, and to treat sludges from both industrial and municipal applications. The process has also been shown to be successful in the recovery of powdered activated carbon for wastewater applications. Through the years, powdered activated carbon recovery has been associated with thermal techniques such as fluid bed furnace or multiple hearth furnace technologies, in which the complicated process of dewatering and drying of the spent carbon prior to processing is required. With wet oxidation, however, all material remains in a slurry. And at the right operating conditions, sorbed and associated organics are destroyed, PAC is recovered for reuse, and autothermal regeneration occurs, making the process a non-fuel user.

The technical paper will discuss the influence of wet oxidation on powdered activated carbon characteristics, and how wet oxidation is applied to successfully recover the powdered carbon when it is used to treat wastewaters. Case studies will be included to verify wet oxidation's suitability for such applications.