Absorption of PCDD/F Emissions in Flue Gas Using Activated Carbon Injections in South Africa

Abstract

South Africa is currently confronted with significant challenges related to the compliance of incineration facilities as incinerators are a major source of polychlorinated dibenzo-pdioxins and polychlorinated dibenzofurans (PCDD/Fs) and have become a significant issue in both environment and public health.The objective of this study was to assess the effectiveness of activated carbon injections in absorbing PCDD/Fs from the flue gas emissions.The ∑TEQ was initially calculated at 46.36 ng I-TEQ Nm -³ but saw a substantial reduction to 10.64 ng I-TEQ Nm -³ following AC treatment.This study was able to achieve an overall removal efficiency of 85%.Notably, highly chlorinated congeners exhibited higher removal efficiencies, indicating the selective adsorption properties of activated carbon.It was also observed that there was a correlation between PCDD/F congeners and flue gas compositions during the activated carbon treatment as congeners reacted with HCl to reduce the chlorine in synthesis of PCDD/Fs.While the activated carbon injections did lead to a notable reduction in PCDD/Fs, the surface area and porosity of the activated carbon also influenced removal efficiency.It is recommended that activated carbon with higher absorption capacity be used to enhance overall efficiency, with further modification to increase surface area and absorption for even greater effectiveness.However, despite the promise shown by activated carbon treatment in reducing PCDD/F emissions, further optimization and technological advancements are necessary to meet stringent regulatory standards.