Using fly ash as a raw material,porous ceramic particles with an apparent density of 1.21 g/cm^(3),a visible porosity of 51.03%,and a specific surface area of 4.26 m^(2)/g were prepared and used as biofilter materials...Using fly ash as a raw material,porous ceramic particles with an apparent density of 1.21 g/cm^(3),a visible porosity of 51.03%,and a specific surface area of 4.26 m^(2)/g were prepared and used as biofilter materials for wastewater treatment.Through SEM,XRD analysis,and heavy metal leaching analysis,it was found that porous ceramsite were porous materials with rough surfaces.After calcination,the newly formed mineral was silicate calcium feldspar.The heavy metal concentration in the leaching solution of porous ceramsite met the national surface water quality requirements.The treatment of domestic sewage showed that the volumetric loads of COD Cr,NH_(4)^(+)-N,and TN removed by the aerated biofilter were 5.23,0.98,and 0.35 kg/(m^(3)·d),respectively,with removal rates of 85.46%,96.13%,and 32.31%.展开更多
Fly ash used as the main raw materials,incorporated with sintering expansion additive and fluxing additive in different ratio,was sintered high-strength lightweight aggregates of fly ash (ceramsite) in the laboratory-...Fly ash used as the main raw materials,incorporated with sintering expansion additive and fluxing additive in different ratio,was sintered high-strength lightweight aggregates of fly ash (ceramsite) in the laboratory-controlled electric furnace.The results show that the optimal sintering system is the sintering temperature range of 1250 ℃ to 1280 ℃ and retaining time of 5 min-10 min.The bulk density,the apparent density and 24 h water absorption of ceramsites decrease with the increase of sintering additive and the decrease of the amount of fly ash.The addition of fluxing additive can significantly enhance the compressive strength of ceramsite pellets,reduce its water absorption at 24 h and improve pore-shape ofinner structure.The firing coefficient (Pk) changed within 7.8-8.1 of raw materials can prepare high strength and low water absorption ceramsites.Pk kept a good linear relationship with porosity and strength of ceramsite particles.展开更多
文摘Using fly ash as a raw material,porous ceramic particles with an apparent density of 1.21 g/cm^(3),a visible porosity of 51.03%,and a specific surface area of 4.26 m^(2)/g were prepared and used as biofilter materials for wastewater treatment.Through SEM,XRD analysis,and heavy metal leaching analysis,it was found that porous ceramsite were porous materials with rough surfaces.After calcination,the newly formed mineral was silicate calcium feldspar.The heavy metal concentration in the leaching solution of porous ceramsite met the national surface water quality requirements.The treatment of domestic sewage showed that the volumetric loads of COD Cr,NH_(4)^(+)-N,and TN removed by the aerated biofilter were 5.23,0.98,and 0.35 kg/(m^(3)·d),respectively,with removal rates of 85.46%,96.13%,and 32.31%.
文摘Fly ash used as the main raw materials,incorporated with sintering expansion additive and fluxing additive in different ratio,was sintered high-strength lightweight aggregates of fly ash (ceramsite) in the laboratory-controlled electric furnace.The results show that the optimal sintering system is the sintering temperature range of 1250 ℃ to 1280 ℃ and retaining time of 5 min-10 min.The bulk density,the apparent density and 24 h water absorption of ceramsites decrease with the increase of sintering additive and the decrease of the amount of fly ash.The addition of fluxing additive can significantly enhance the compressive strength of ceramsite pellets,reduce its water absorption at 24 h and improve pore-shape ofinner structure.The firing coefficient (Pk) changed within 7.8-8.1 of raw materials can prepare high strength and low water absorption ceramsites.Pk kept a good linear relationship with porosity and strength of ceramsite particles.
基金supported by the National Key Research and Development Program of China(No.2020YFC1909202)the Postdoctoral Foundation of China(Nos.BX20200389,2020M672513)the National Natural Science Foundation of China(No.52004343)。
