城市垃圾焚烧飞灰添加到烧结工艺的影响

Effect on sintering process by adding fly ash from municipal solid waste incineration

垃圾焚烧飞灰为城市垃圾焚烧烟气净化系统和余热回收系统中收集而得到的残余物,其产生量约为垃圾焚烧量的3%~10%。因为飞灰中含有多种重金属和二噁英而被列为危险废物。本试验将焚烧飞灰添加到铁矿石烧结工艺中,研究了飞灰的添加对烧结工艺的影响。烧结试验结果表明,添加飞灰后,提高了残留在烧结矿中的Cl、S、K和Na等元素的含量,烧结成品率有所下降,转鼓指数略有变化;但添加飞灰后,烧结矿成品的还原强度指数、低温还原粉化指数、耐磨指数等指标有明显的提高。同时,添加飞灰烧结后,烧结尾气中的二噁英、SO2、Cl、K、Na等元素含量也明显增加。

Municipal solid waste incineration fly ash is the residue from the flue gas cleaning system and waste heat recovery system of municipal waste incinerating processes, the output is about 3%-10% of the quantity of incinerating waste. It is identified as hazard waste, for several heavy metals and dioxin in flash ash. In the research, the fly ash was blended into iron ore, and the influence on the sintering process was studied. The experiment results showed that the content of Cl,S,K and Na in sinter was increased after adding fly ash, the yield of sinter was decreased, the drum strength was slightly changed. The indexes of reduction strength, RDI and abrasion resistance were significantly improved. At the same time, after sintered, the content of dioxin, SO2,Cl,K,Na in the sintering tail gas were also significantly increased after the addition of fly ash.