After mixing municipal solid waste incineration fly ash (MSWIFA) with silica fume and a certain proportion of deionized water, natural curing, steam curing and thermal treatment were performed respectively to stabilize heavy metals. The effects of additive amounts of silica fume on the leaching of critical heavy metals in MSWIFA with natural curing and steam curing were studied. Specification distribution of heavy metals, crystal structures and microstructures of steam curing samples and thermal treatment samples were also investigated. The results showed that the leaching concentrations of Pb, Cd, Cr and Cu gradually decreased with the addition of silica fume from 0% to 10% while using natural curing and steam curing. When adding 10% silica fume, the leaching concentration of Pb, Cd, Cr and Cu for natural curing samples were slightly higher than that for steam curing samples, in which specification distribution of heavy metals did not show significant change as compared with that in raw fly ash. Highly effective heavy metal stabilization of thermal treatment for Pb, Cd, Cu and Zn could be achieved, proven by leaching test results and specification distribution of heavy metals. The ratios of residue state of Pb, Cd, Cu and Zn in fly ash after thermal treatments increased from 37.12%, 11.82%, 44.30% and 51.94% to 84.75%, 75.49%, 77.20% and 67.40%, respectively, while the ratios of acid soluble state decreased from 3.99%, 54.92%, 6.56% and 10.49% to 0.44%, 9.37%, 2.72% and 3.59%, respectively.
李军辉, 吴新, 刘道洁, 王开. 不同处理方法对硅灰稳固化垃圾焚烧飞灰重金属的影响[J]. 中国环境科学, 2018, 38(11): 4198-4204.
LI Jun-hui, WU Xin, LIU Dao-jie, WANG Kai. Effects of different treatment methods on the stabilization of heavy metals in municipal solid waste incineration fly ash using silica fume. CHINA ENVIRONMENTAL SCIENCECE, 2018, 38(11): 4198-4204.
Bontempi E, Zacco A, Borgese L, et al. A new method for municipal solid waste incinerator (MSWI) fly ash inertization, based on colloidal silica[J]. Journal of Environmental Monitoring Jem, 2010,12(11):2093-2099.
[7]
Rodella N, Bosio A, Dalipi R, et al. Waste silica sources as heavy metal stabilizers for municipal solid waste incineration fly ash[J]. Arabian Journal of Chemistry, 2014,130(S2):3676-3681.
[8]
Bosio A, Gianoncelli A, Zacco A, et al. A new nanotechnology of fly ash inertization based on the use of silica gel extracted from rice husk ash and microwave treatment[J]. Proceedings of the Institution of Mechanical Engineers Part N Journal of Nanoengineering & Nanosystems, 2014,228(1):27-32.
[9]
Bosio A, Rodella N, Gianoncelli A, et al. A new method to inertize incinerator toxic fly ash with silica from rice husk ash[J]. Environmental Chemistry Letters, 2013,11(4):329-333.
[10]
Rodella N, Bosio A, Zacco A, et al. Arsenic stabilization in coal fly ash through the employment of waste materials[J]. Journal of Environmental Chemical Engineering, 2014,2(3):1352-1357.
[11]
Li X, Chen Q, Zhou Y, et al. Stabilization of heavy metals in MSWI fly ash using silica fume[J]. Waste Management, 2014,34(12):2494-2504.
Umoren I U, Udoh A P, Udousoro I I. Concentration and chemical speciation for the determination of Cu, Zn, Ni, Pb and Cd from refuse dump soils using the optimized BCR sequential extraction procedure[J]. Environmentalist, 2007,27(2):241-252.
[17]
GB 16889-2008生活垃圾填埋场污染控制标准[S].
[18]
Hu H, Luo G, Liu H, et al. Fate of chromium during thermal treatment of municipal solid waste incineration (MSWI) fly ash[J]. Proceedings of the Combustion Institute, 2013,34(2):2795-2801.
