Effect of moderate temperature on PCDD/Fs removal in domestic incineration fly ash by horizontal ball milling
In order to overcome the shortcomings of low energy utilization of the horizontal ball milling method,moderate-temperature treatment of water-washed fly ash by horizontal ball milling was carried out by coupling pyrolysis technology with a mechanochemical method.The results showed that after moderate-temperature ball milling of the fly ash,the average particle size was reduced and the particle size distribution was more uniform.PCDD/Fs included PCDFs and PCDDs.The concentration and toxicity equivalent concentration of PCDD/Fs,PCDDs,and PCDFs were reduced with the increase in temperature,and when the temperature reached 450 ℃,the degradation rates of PCDD/Fs,PCDDs and PCDFs reached 95.83％,95.67％and 96.17％,respectively.Meanwhile,the mass fraction of PCDD/Fs was reduced from 469.32 ng·kg-1 to 19.55 ng·kg-1,and the toxic equivalent reduced from 35.06 ngTEQ·kg-1 to 2.30 ngTEQ·kg-1.Among them,PCDDs were preferentially degraded,and part of PCDFs was converted into PCDDs.After the fly ash was milled at a moderate temperature,the chlorinity of the fly ash was significantly reduced,which was consistent with the PCDD/Fs removal pattern.
万方数据
维普
