The distributions in different particle sizes of municipal solid waste incinerator (MSWI) fly ash in spring and autumn were studied by sieve method, and the heavy metal contents of Cu, Zn, Mn, Pb, Cd, Ni, Cr and Hg in different size particles were measured, and the heavy metal leaching amount in the different particle size were also studied under the GB5085.3-2007 and USEPA-TCLP leaching procedure, respectively. The results showed that the particle size of fly ash in autumn was relatively smaller than that of in spring, more than 90% of particle size of fly ash in spring and autumn were less than 250 μm, and the particle size in 83-105 μm of fly ash in spring distributes in most with about 40% of the total, but 105-149 μm in autumn distributes in most, accounted for about 45% of the total. The content of heavy metals decreased first and then increased with the decreasing particle sizes except for Ni, and the content of heavy metals in the spring is higher than that of in autumn except for Fe and Zn. Under the GB5085.3-2007 leaching procedure, the leaching content of Cu, Zn and Ni in MSWI fly ash in both spring and autumn and Cr in spring were not beyond limited standard, but Pb and Cd in both spring and autumn and Cr in autumn were beyond limited standard. However, under TCLP leaching procedure, the leaching content of Pb, Cr and Cd in both spring and autumn were beyond the standard limits.
Leaching of Heavy Metals from Fly Ash Generated from Gasification and Melting Furnace for Municipal Solid Wastes by Organic Acids
