Author 1:
Name & Surname: Borzakovsky B. A.
Company: Galurgia Research and Design Institute (Perm, Russia)
Work Position: Head of laboratory
Scientific Degree: Candidate of Engineering Sciences
Contacts: rusakov.mihail@gallurgy.ru

Author 2:
Name & Surname: Rusakov M. I.
Company: Galurgia Research and Design Institute (Perm, Russia)
Work Position: Researcher

Clay-and-salt slurry of potassium processing is a suspension of solids in pregnant solution of NaCl+KCl. Slurries are mainly placed in slurry ponds that occupy an area of nearly 800 ha at mines of the Upper Kama Potash Deposit. Slurry ponds are the source of the long-term salination of ground water and the land they occupy are irreparable loss. At the present time, slurry is partly placed in underground mines using two technologies: slurry is mixed with slime pulp and is placed in special-purpose slurry cells. The density of settlings in the slurry cells is 1.65 t/m³. Aiming at enlarging the volume of slurry placed in mined-out voids, it is suggested to use geotubes (dewatering bags) made of high-strength synthetic fabric and placed in underground excavations. Pilote dewatering testing of hot slurry of mineral salt production plant at Solikamsk Mine-1 and cold slurry of flotation plant at Solikamsk Mine-2, using 70 l dewatering bags made of polypropylene grade PP 105/105 showed good dewatering capacity. Maximum density of dewatered slurry was 1.94 t/m³ for Solikamsk Mine-1 and 1.75 t/m³ for Solikamsk Mine-2. After the beneficial effect of the test dewatering, a full scale experiment was carried out in mine. A geotube 50 m long with a perimeter of 8 m was placed in a service entry driven in rock salt. Slurry with a density of 1300 kg/m³ was fed in the geotube. After the experiment, the slurry settlings were sampled from the geotube. The settlings had density from 1.65 to 1.87 t/m³ and moisture content from 20 to 54%. Based on the experimental result, the scheme was developed for placing slurry in geotubes in underground excavations meant for hydraulic fill. A geotube is placed in an excavation on a lower lying level and is filled with slurry settlings in a few cycles of slurry feed and saline solution removal (filtration). Clarified saline solution removed from the geotube is pumped out. Then, a filling mass made of salt waste is placed above the geotube filled with slurry. Under the weight of the filling mass, the slurry in the geotube is compacted, and its density becomes approximately equal to the density of the salt waste backfill.

1. Borzakovskiy B. A., Rusakov M. I., Shilov A. V. Opyt razmeshcheniya glinisto-solevykh shlamov na kaliynykh rudnikakh Verkhnekamskogo mestorozhdeniya (Experience of placing of clay-salt slimes on potassium mines of Verkhnekamskoe deposit). Izvestiya vuzov. Gornyy zhurnal = Proceedings of universities. Mining journal. 2009. No. 6.
2. Borzakovskiy B. A., Papulov L. M. Zakladochnye raboty na Verkhnekamskikh kaliynykh rudnikakh : spravochnik (Stowing operations at Verkhnekamskoe potassium mines : reference book). Moscow : Nedra, 1994.
3. Adzhienko V. E., Ermolaev S. V., Yarygina A. A. Ispolzovanie geotekstilnykh konteynerov dlya obezvozhivaniya i skladirovaniya otkhodov (Use of geotextile containers for dehydration and warehousing). Ekologiya proizvodstva = Industrial ecology. 2010.