Effect of Fe <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="d1e72" altimg="si2.svg"> <mml:mrow> <mml:msub> <mml:mrow/> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> <mml:msub> <mml:mrow> <mml:mi mathvariant="normal">O</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>3</mml:mn> </mml:mrow> </mml:msub> </mml:mrow> </mml:math> on the leaching behavior of Cr in hazardous waste incineration fly ash after thermal treatment
Yuyang Long, Junjian Qiu, Qiqi Bao, Foquan Gu, Zixiao Wu, Minjin Wu, Wenxin Guo, Dongsheng Shen
Abstract
The effect of Fe2O3 on the leaching behavior of Cr in hazardous waste incineration fly ash (HWFA) after thermal treatment was investigated. Addition of Fe2O3 could inhibit the static leaching behavior of Cr at most temperature conditions: the maximum reduction in leaching was 98.3% at 1200 °C. Long-term dynamic leaching behavior of Cr could be inhibited when using a thermal treatment temperature of 1200 °C and proportion of Fe2O3 exceeding 14.3%. At 1200 °C, Fe2O3 reacted strongly with the hazardous fraction of Cr in HWFA to form a stable chromite (Fe+2Cr2O4). The study results illustrate that the leaching behavior of Cr in HWFA after thermal treatment is affected by addition of Fe2O3 and treatment temperature. Adding Fe2O3 could effectively control the static and dynamic leaching behavior of Cr in HWFA after thermal treatment at 1200 °C, but excessive Fe2O3 addition accelerated dynamic leaching rate of Cr in HWFA after thermal treatment at 1100 °C.