两种抑制剂对铁矿石烧结过程二噁减排研究

Study on dioxin emission inhibition effect by addition of two inhibitors in iron ore sintering process

研究了尿素和碳酰肼对烧结过程二噁减排的影响,添加量分别是0.01%,0.02%,0.05%,0.1%(ω:质量浓度).结果表明,两者均对二噁减排效果显著,其中,尿素对应的减排率随尿素的加入量有所波动,加入量为0.02%时,二噁的毒性当量排放浓度减少了67.74%,为实验最高值.碳酰肼对应的减排率在实验范围内随加入量升高而升高,在最高加入量0.1%处二噁的毒性当量排放浓度减少了78.79%.两种抑制剂都没有改变二噁同系物的分布规律,对铁矿烧结过程二噁同系物形成的抑制作用在绝大范围内是一致的,只有OCDD与OCDF表现出差异性.添加极少量的尿素和肼这2种抑制剂不会给烧结生产带来明显的影响.

The inhibition effects on dioxin emission from iron ore sintering process were compared for two inhibitors through a series of sintering-pot experiments.The additions of the two inhibitors,namely urea and carbohydrazide,in the sintering iron ore mixture were arranged as 0.01%,0.02%,0.05% and 0.1%（ω） respectively.The results showed that both inhibitors can reduce dioxin emission significantly.For the case of urea inhibitor,the reduction efficiencies of dioxin emission fluctuated with its addition with the highest efficiency 67.74% appeared at the addition of 0.02%;while for carbohydrazide inhibitor the reduction efficiencies of dioxin emission increased with its addition and the highest efficiency reached 78.79% as 0.1% of carbohydrazide was added.Both inhibitors did not change the finger print of dioxin homologues.The inhibition effect on all dioxin homologues formation by urea was coincident with that by carbohydrazide,namely,the isomer distribution of dioxin emissions were not essentially changed except that OCDD and OCDF behaved different for the two inhibitors.Both inhibitors did not change sintering indexs significantly.