The effects of the mechanical-chemical stabilization process for municipal solid waste incinerator fly ash on the chemical reactions in cement paste.

A water extraction process can remove the soluble salts present in municipal solid waste incinerator (MSWI) fly ash, which will help to increase the stability of the synthetic materials produced from the MSWI fly ash. A milling process can be used to stabilize the heavy metals found in the extracted MSWI fly ash (EA) leading to the formation of a non-hazardous material. This milled extracted MSWI fly ash (MEA) was added to an ordinary Portland cement (OPC) paste to induce pozzolanic reactions.

Mechanochemically induced synthesis of anorthite in MSWI fly ash with kaolin.

The process of mechanical milling has been found to effectively stabilize heavy metals in municipal solid waste incinerator (MSWI) fly ash, as well as to restrain the evaporation of heavy metals during thermo-treatment. This method is adopted in this study and the composition and degree of amorphization adjusted to improve the efficiency of crystalline anorthite synthesis. Different milling times (1, 5, 10 and 20 h) and different sintering temperatures (900, 950, 1000, 1100, 1200 and 1300 °C) are utilized.

Direct observation of charge ordering in magnetite using resonant multiwave x-ray diffraction.

Charge disproportion at octahedral Fe sites in magnetite was observed at low temperature using two inversion-symmetry related three-wave resonant x-ray diffraction, 022-311 and 002-̅3̅1, near the iron K edge. Both of the three-wave cases involve the (002) forbidden-weak reflection. The self-normalized three-wave to two-wave (002) diffraction intensity ratio automatically cancels the self-absorption effect and leads to direct determination of charge disproportion for magnetite below 120 K.