Improvement of hydraulic extraction methods for moist sapropel

The analysis of stable extraction methods for moist sapropel at minimized environmental impact is presented. The mathematical model to determine safe volume and optimal method for extraction of sapropel with natural moisture content from under an overburden layer and without mixing with water is proposed. The dependence of the optimized safe volume of extraction on the subsidence depth of the overburden layer and structural shear resistance of sapropel is found for three different methods of sapropel extraction without its mixing with water: 1—cone of depression; 2—trench of depression; 3—scraper trench. The proposed submersible cell-type suction head with integral eccentric-driven screw pump and scraper bucket is capable to travel in sapropel beds at the preset depth, and to ensure stable extraction of sapropel with natural moisture content within a wide range of shear strengths for sapropel of various grades and various rheology. It is concluded that it is required to optimize extraction techniques for sapropel with natural moisture content to eliminate mixing of sapropel with water and to ensure thereby the minimized environmental impact on a water body and adjacent territory.

Dementjev V. A. Improvement of hydraulic extraction methods for moist sapropel. MIAB.MiningInf.Anal.Bull.2021;(7):42-52.[InRuss].DOI:10.25018/0236_1493_2021_7_0_42.

V.A. Dementjev, Cand. Sci. (Eng.), Member of the Board, EHT Engineering Ltd., LV-2101, Riga, Latvia, e-mail: vladementjev@mail.ru.

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