Mehhaniseeritud laavakompleksist väljatud põlevkivi tootmis- ja töötlemisjääkide ringmajandusliku ja ressursitõhusa kasutuse terviklikud lahendused [Bakalaureusetöö. Juhendaja: E. Väli]

The mining capacities are increasing year by year in Estonian mines and also due to that there is growth in the losses, waste amounts and environmental taxes. One of the solution to reduce those downsides is to start backfilling.

The following graduation thesis is aimed to take backfilling as one possible solution to reduce taxes and save enviornment. It is done by giving complete solutions for backfilling in longwall mining and selecting the most resource effective way to dump tailings under ground.

At the moment there is no working technology for backfilling but studies have been conducted in recent years with positive results. However, there are countries in the world who have been using backfilling method for over one century. There are many examples with various different hazardous waste used to backfill coal, salt and ore mines.

This thesis was done to give complete solutions for backfilling project on Narva quarry longwall mining facility. For demonstration there were made different technological schemes and plots. The project will cost to the company around 10 mln € to start and around 1 mln € per year to run.

The results suggest that backfilling in Narva quarry is reasonable and resource effective. Also the economic calculations prove that if the company would sell the splinters made from waste there would be gainfulness in 2-3 years. The thesis suggests that if it is not possible to sell the splinters the payback time would increase 3 times and it would not be profitable to start backfilling. On the basis of the results of this research, it can be conluded that all the mining residues can be used for backfilling and there will be no environmental taxes on tailings.