Legal, ecological and technological aspects of the mass production of lightweight concretes based on high volume of coal ashes

In an earlier publication in the framework of the 22^nd Annual International Pittsburgh Coal Conference we reported the preliminary results of a R&D program related to the development of a technology for the combined utilization of bottom ash, fly ash and a byproduct of stone quarries (unprocessed crushed sand) for the manufacture of ecologically friendly lightweight concrete with desirable building characteristics. In the recent months we made progress in the further development of this technology. Our efforts are concentrated on the solution of problems related the mass production of the ternary lightweight concrete. Special attention has been given to the study of radiological characteristics of coal ashes from different sources and lowering the activity concentrations of radionuclides in the lightweight concrete based on coal ashes. The results of our theoretical and experimental studies will be reported.