碳酰肼对烧结过程二噁英生成的抑制作用

Inhibitory effect of carbohydrazide on PCDD/Fs formation in iron ore sintering process

研究了碳酰肼对钢铁厂烧结工序产生的二噁英的抑制效果。结果表明,添加了0.01%(质量分数,下同)、0.02%、0.05%、0.10%的碳酰肼之后,二噁英的排放质量浓度降为0.560、0.506、0.270、0.174ng-TEQ/m3,相对于基准值(0.821ng-TEQ/m3)大幅减少。碳酰肼对二噁英的从头合成以及前驱物生成都能起到一定的抑制效果。碳酰肼与Cu2+结合生成稳定的氮化物,削弱Cu2+的催化活性;与HCl反应,减少了生成二噁英的氯源;对FeCl3、CuCl2的催化活性也会产生影响。碳酰肼添加后,对多氯代二苯并呋喃(PCDFs)生成中高氯代二噁英的脱氯行为也有明显的抑制。

The emission reduction experiments of dioxins from iron ore sintering process with addition of carbohydrazide as inhibitor were carried out.The results show that when adding 0.01%,0.02%,0.05% and 0.10%（weight ratio）carbohydrazide,the emission concentrations of dioxins are 0.560,0.506,0.270 and 0.174 ng-TEQ/m3,remarkably decreased compared with 0.821 ng-TEQ/m3 without adding carbohydrazide.Both the de novo synthesis and the formation from precursors of PCDD/Fs would be suppressed with addition of carbohydrazide.Carbohydrazide would weaken catalytic activity of Cu2＋ by reacting with Cu2＋ and formation the stable nitrogen compounds,it could also reduce the chlorine source of dioxins by reacting with HCl and impact on catalytic activity of FeCl3 and CuCl2.Dechlorination of higher chlorinated PCDFs would be suppressed with addition of carbohydrazide at the same time.