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Analcime-bearing rocks are rather widespread in the Timan region (Komi Republic, Russian Federation). The geologists from the Institute of Geology and industrial organizations isolated the Timan zeolite province with predominance of analcime in productive sediments. Analcime-bearing rocks from Carboniferous and Permian sediments occupy a vast area in the Timan - about 150000 km2.
Analcime-bearing rocks are represented by siltstones and mudstones. They have the following mineral composition (%): clay minerals (50-70 %), quartz (10-30 %), analcime (1-30 %), feldspars (2-10 %), carbonates (2-5 %), pyroclastic material. Analcime aggregates encrust cavities and infill microfissures in rock. Thin sections of analcime demonstrate distinctly different stages of its development in cavities ranging from insignificant encrusting to complete filling. Both microcrystalline (crystals < 0.01 mm in size) and medium-crystalline (∼ 0.5 mm) aggregates are observed.
Mechanical, gravitational, magnetic, sorption, ion-exchange properties of analcime-bearing rocks is studied. They are characterized by high index of grindability and low index of abradability and crush resistance, low values of the benzol-based pore volume, toluene-based specific surface, and medium porosity value.
The Ar-based specific surface of the analcime-bearing rocks value varies from 9.08 to 21.37 m2/g. The Ar-based specific surface of pure analcime is 1.5 m2/g. The magnesium based ion-exchange capacity (IEC) ranges from 28.7 to 196 mg•equiv/100 g. The IEC of analcime is 21.5 mg•equiv/100 g. Probably, the sorption and ion-exchange properties depends more on the content of clay minerals than on the content of analcime.
Analcime-bearing rocks of the Timan region are characterized by low dressability. Preliminary ultrasonic treatment of the analcime-bearing rocks is efficient for the destruction of intergrowths along their boundaries and production of free analcime aggregates. The proposed dressing procedure yields 95 % analcime concentrate.
In the Komi Republic, analcime-bearing rocks are utilized in agriculture. They are also used for domestic needs (e.g. as biotoilets for domestic animals) and the solution of ecological problems (regeneration of soil polluted by oil). We have concluded experiments with the purification of potable and technical water by the analcime-bearing rock subjected to thermal treatment. The experiments made it possible to decrease water coloration by 20 %, turbidity by 79 %, permanganate oxidation by 30 % and total iron content by 70 %. The method of water purification is patented.
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