A retrospection on the content, association, and significance of mercury in coals and coal ashes from Bulgarian thermoelectric power stations.

A short overview on the content, association, and significance of toxic Hg in 9 coal types and their fly ashes (FAs) from 12 Bulgarian thermoelectric power stations (TPSs) was conducted by a compilation of reference and our own data obtained by a combination of different chemical and mineralogical analyses, and separation procedures. The Bulgarian and Ukrainian coals studied are enriched in Hg (0.14-0.

Mineral Carbonation of Biomass Ashes in Relation to Their CO Capture and Storage Potential.

Short-term stored, long-term stored, and weathered biomass ashes (BAs) produced from eight biomass varieties were studied to define their composition, mineral carbonation, and CO capture and storage (CCS) potential by a combination of methods. Most of these BAs are highly enriched in alkaline-earth and alkaline oxides, and the minerals responsible for CCS in them include carbonates such as calcite, kalicinite, and fairchildite, and to a lesser extent, butschliite and baylissite. These minerals are a result of reactions between alkaline-earth and alkaline oxyhydroxides in BA and flue CO gas during biomass combustion and atmospheric CO during BA storage and weathering.