Lifting of solid material in underwater extraction of minerals from the seabed to the water surface is the most effective hydraulic method through a vertical pipeline. The method with the use of an airlift unit or a pumping unit is possible. Generalized energy characteristics of the airlift and pumping methods of hydraulic lifting of mineral resources for choosing a rational and cost-effective hydraulic transport system are given. Calculated dependencies for determining the specific energy losses when lifting the rock mass from the surface of the seabed at a depth of 100 m are presented. These hydraulic lifting systems can be considered as modular even in case of increasing the development depth up to 1000 m. The total number of hydraulic lift stages will be a multiple of the depth of the modular stage. Obtained in this work energy characteristics of the airlift unit are inferior to the pump method of hydraulic lift in terms of efficiency.
The system of hydraulic transport in underwater mining of solid minerals, which consists of two parts: - a horizontal pipeline; - a vertical pipeline is considered. The most complicated section of vertical hydraulic transport is also presented. Operation of the vertical hydraulic transport system consists in the two-stage process of lifting the hydro-mixture of the mineral from the bottom sump to the vessel. At the first segment, from the sump to the immersion capsule, the lift is carried out due to the difference between the hydrostatic pressure at the immersion depth of the capsule and the atmospheric pressure. The calculation formulas for determining the optimal submersion depth of the capsule depending on the depth of the underwater deposit, concentration of the solid material in the volume of the hydro-mixture, system capacity and other characteristics are presented. Adequacy of theoretical formulas should be confirmed by experimental results, which is the subject of further research.
