Comparison of energy costs in terms of hydraulic rock lifting capacity by the airlift and pumping methods

Abstract

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.