|
|
|
| Release characteristics of heavy metals in cement product from co-processing waste in cement kiln. |
|
|
|
|
Abstract Clinker used in this experiment was produced by simulating cement calcination test, and concrete samples were prepared from the clinker. The release characteristics of heavy metals in concrete was studied by using two leaching methods, EA NEN 7371 and EA NEN7375. Availabilities of the heavy metals were lower than the total amounts in concrete. Ratios of availability to total amount were of great difference among each heavy metal and the ratio of Ni(64.6%) was the biggest among five heavy metals(Cr, Ni, As, Cd, Pb). The major release mechanism of the Cr, Ni, and Cd was diffusion control and the release curves fitted the standard line well with a slope of 0.5 and that of different increments were all between 0.35 and 0.65. Leaching of As appeared delayed-stagnant phenomena initially, but diffusion control was still the major mechanism in middle and later leaching period. Release of Pb was controlled by solution and influenced significantly by eluates pH. The negative logarithm of diffusion coefficient of each heavy metals changed as the following order: Pb
|
|
Received: 30 July 2008
|
|
|
|
| [1] |
CHEN Huan-Yu, LIU Jing-Qing, WEI Zong-Yuan, ZHANG Hui-Hui, HE Xiao-Fang, ZHOU Xiao-Yan, QIU Shang-De, HU Bao-Lan, LOU Li-Ping. Radial differences in contaminant distribution in large-diameter pipe scales of main pipelines in drinking water distribution system[J]. CHINA ENVIRONMENTAL SCIENCECE, 2015, 35(9): 2706-2712. |
|
|
|
|
