New method to neutralise flooded opencast mines

Pilot project

Lignite can only be extracted from opencast mines if the ground water level is lowered to below the coal seam. This has a strong influence on the region’s water balance. Depending on the chemism from the overburden, the rising ground water after mining  in the pit lake may become acidic due to pyrite weathering. Thus ground water remediation projects seek to balance out the ground water deficit and to neutralise the lakes in the former mines so that flora and fauna may be established.

Lime is usually used in this process for example using ships to introduce lime into the lake water with sprinkler systems. Large quantities of lime are needed to treat an entire water body, however, as there is only a low level of blending that takes place in the process. GMB GmbH developed the UNP-Underwater Nozzle Pipelines (German: GSD-Getauchte Schwimmleitung mit Düsen) method as an alternative: lime mixed with lake water is pumped through the nozzles of floating pipes into the lake, where it uses the natural lake circulation to blend thoroughly, distributing the suspension evenly...

Related articles:

Issue 2022-07-08 Strategies for economical use of water

Quality ‘cascade’ can optimise water treatment on mines

Relatively little water used during mining and processing needs to be clean or potable, so mines can reduce both water consumption and treatment costs by understanding what water qualities are needed...

Issue 2014-09 Water Scarcity in Mining

Water management

Water Scarcity in Mining

1 Introduction At the present time, more than one billion human beings are living in regions that are suffering from water shortages. Forecasts predict that by the year 2030 this number will have...

Issue 2015-09

BAUER Perforation Cutter for hard soil layers in underwater extraction

Last year, BAUER Maschinen GmbH developed an individual solution for the requirements of Meichle + Mohr GmbH from Immenstaad on the north shore of Lake Constance: the prototype of the BAUER...

Issue 2016-06


Dear Readers Many companies are increasingly specializing in equipment and process solutions, which are tailored to the individual requirements of their customers. Two special articles in this...

Issue 2015-06

Horizon 2020 programme to develop Underwater Mining Systems

As part of the Horizon 2020 programme, a new 42 month   Research & Development Project, has been launched to help provide an opportunity to tap into the wealth of unexploited European mineral...