Suppression of PCDD/Fs by Raw Meal in Cement Kilns

Xiaoqing Lin ； Longjie Ji ； Mingxiu Zhan ； Lingshu Wang ； Tong Chen ； Shengyong Lu ； Xiaodong Li ； Jianhua Yan

《Aerosol and Air Quality Research》 18卷4期 (2018/04) Pp. 1032-1043+ap1-1

https://doi.org/10.4209/aaqr.2018.01.0023

摘要

Raw meal of the cement production process could probably suppress the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). In this study, these suppression effects were studied and compared during the co-processing of municipal solid waste (MSW) with conventional feed materials such as pure CaCO_3, and pure CaO. A top suppression efficiency of 96% was achieved for a ratio of MSW to raw meal of 1:15. Moreover, NaCl and CuCl_2 were added to the mix of feed material and MSW, to reveal the impact of additional chlorine and cations on PCDD/F formation. Similarly, the raw meal was mixed with the kiln dust to investigate possible suppression effects of those PCDD/Fs formed through the precursor or the de novo synthesis at a temperature of 350°C. The raw meal suppressed the formation of PCDD/Fs from kiln dust. Furthermore, the raw meal could not suppress the formation of PCDD/Fs on mixtures of kiln dust and NaCl or CuCl_2, which could be associated with a potential increase in the formation effects of PCDD/Fs on the raw meal. The results can help in potential decision-making on the applicability of certain cement kilns on the co-processing of MSW containing high levels of Cl and Cu.

關鍵字

PCDD/Fs ； Cement kiln ； Raw meal ； Suppression ； MSW co-processing