Method and apparatus for extracting sediments on deposits under water

摘要

The extraction of sediments, in particular sediment layers and/or sediment mixtures which mostly consist of sand and to a lesser extent contain clay, silt and gravel, is to be effected in deposits constantly under water, e.g. in lakes and rivers, over their entire depth down to the bottom of the body of water. To this end, a pressure-water jet is directed from the water side against a soft sediment layer of the working face or wall and a notch is formed in this sediment layer. The overhang thereby formed on the working face or wall breaks off and, while dissolving the inner bond between the deposit particles, plunges down to the bottom of the body of water while forming a slope, from where the material can be conveyed, for example by means of suction dredgers. In the process, work is carried out with at least one jet pipe or jet nozzle which on the one hand is anchored to a supporting structure in the form of a floating body arranged above the water level and on the other hand is connected to a pressure pump, for example with a pressure line in between.