Microbe cement, a new type of gelling material, has attracted wide attention due to the increasing
awareness of environmental protection. In this paper, the microbe cement in solidifying municipal solid waste
incineration (MSWI) fly ash is investigated and the effect of the microbial induction method in solidifying MSWI
fly ash is compared with the traditional chemical reaction strategy by characterizing the resulted calcite and the
solidification productions with electronic universal testing machine, X-ray diffractometer (XRD), Fourier transform
infrared spectrometer (FTIR), scanning electron microscope (SEM) and atomic absorption spectrometer. The
results show that the MSWI fly ash solidified by microbe cement has the highest compressive strength while that
of the chemical CaCO3 products is the lowest. The XRD results show that a new hydration gelling substance
(Ca2SiO4·0.30H2O) is generated in the MSWI fly ash products. The FTIR results show that the frequency of
Si—O bonds and C—O bonds in the products solidified by microbe cement has shifted, while there is no change
occurred in the chemical CaCO3 products. The SEM results show that the microstructure of the products solidified
by microbe cement is denser than that of chemical CaCO3 products. The test results of heavy metals show that
the microbe cement could reduce the leaching concentration of heavy metals in MSWI fly ash. Ultimately, the
leaching concentration of Pb meets the standard requirements, while that of Cd is still slightly higher than the
standard requirement.
RONG Hui, WEI Guanqi, QIAN Chunxiang, ZHANG Lei, ZHANG Ying, XU Rui
. Mechanism of MSWI Fly Ash Solidified by Microbe Cement[J]. Journal of Shanghai Jiaotong University(Science), 2020
, 25(4)
: 519
-525
.
DOI: 10.1007/s12204-020-2199-7
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