Stabilised Coal Ash Studies in Italy

The ENEL Ash Research Centre - (Brindisi, Italy) - has started a research programme on the use of coal ash derived from its thermoelectric power plants as a component of blocks for artificial habitats. After preliminary laboratory tests, systematic physical, chemical, and biological tests were carried out in an experimental installation constructed in the area of the Torrevaldaliga power plant (80 km NW of Rome).

Two reef models - each made by assembling pyramids of 225 20 × 20 × 20 cm blocks - were submerged in two tanks (10 × 2 × 1.5 m) with running sea water (water flow: 3-5 cm s-1). the ash blocks were composed of fly ash (52.1%), bottom ash (26.1%), hydrated lime (5.2%) and water 16.6%, while concrete blocks were made of pozzolanic cement, sand and gravel. After two years, ash based blocks showed no weathering, volume variation or swelling; marked compressive strength and sonic velocity increases have, on the contrary, been recorded. No significant leaching of chemical elements of environmental concern was found. the biotic settlement on the ash blocks proved greater in quantity and better in quality than that on the concrete blocks; on ash blocks 62 species were found, compared to 54 on concrete. Ash-based materials seem to be more suitable for the settlement of the macrobenthos.     

粉煤灰的多环芳烃在海水中的溶出

用荧光分光光度计测定浸泡粉煤灰海水中多环芳烃（ＰＡＨｓ）的含量,用反相高效液体色谱紫外检测器／荧光检测器测定海水浸泡前后粉煤灰中多环芳烃。热电厂粉煤灰在海水中２种溶出结果表明,其粉煤灰在海水中的静态溶出和吸附可逆,ＰＡＨｓ的溶出极少。热电厂粉煤灰倾倒于海水中溶出的多环芳烃对海洋环境污染甚微。