The most significant source of CO₂ emissions in Poland is the power industry, which is based on conventional fuels: hard coal and lignite. During electricity and heat production, significant amounts of combustion by-products are formed, mainly fly ash. Fly ash is applied in underground mining in Poland as ash-water suspensions that are used to fill underground excavations, as well as for many other high-tech mining procedures. In Poland, 10,653,800 tons of fly ash have been used by the industry, and of those, 5,233,700 tons or 49%, have been used in coal mines.

Fly ash used to bind CO₂ should possess high CaO content, thus causing direct reaction with water. High CaO concentrations are also found in fly ash with exhaust gas desulfurization products (12% CaO). Low CaO concentrations are found in fly ash originating from hard-coal combustion (1% CaO).

The amount of absorbed CO₂ and its influence on the properties of suspensions depend, among other things, on the kind of ash, the ratio of ash to water, and the intensity with which the suspensions are mixed with CO₂. The largest amount of CO₂ was absorbed into the shaken suspensions containing fly ash from lignite combustion after 25 days of seasoning (8.8 g CO₂/100 g).

The idea is to use CO₂ based on its binding by the process of mineral carbonation within water-ash suspensions being deposited in underground mines. The latter might be regarded as a particular form of geological CO₂ sequestration.