Currently, the Polish power industry is mainly based on solid fuels, such as hard coal and lignite, and there is
a problem with the management of significant amounts of combustion waste. One of the directions of recovery
of these types of waste is underground hard coal mining operations, where the general problem of their management is the variability of physical and chemical properties resulting from the combustion of fuels of different
parameters in power boilers with different exhaust gas cleaning solutions, mainly desulphurization methods.
One of the solutions for energy production currently in use is the combustion of coal in fluidized bed boilers,
in which the so-called dry desulfurization method is adopted. As a result of this process, a fine-fraction waste
with the European code 10 01 82 is created, which is characterized by pozzolanic features, enabling its use
wherever specific strength parameters are expected from the material. One such technology is the liquidation of
underground workings based on the pouring of a hydro-mixture into the fenced-off space of the workings using
a gravity-fed pipeline. The space to be filled is fenced off by closing it on both sides with dams, usually made
of brick walls, located at an appropriate distance. It should be taken into account that the hydro-mixture will
tend to slow the sedimentation of solid particles on the spreading path, and working may have a variable slope.
The paper presents the results of laboratory tests of the physical and mechanical properties of hydro-mixtures
made on the basis of selected energy waste from a fluidized bed boiler, along with a practical example of its
application for the liquidation of underground workings.
