Salt-concrete is a construction material that is used to reduce the water inflow in mining

Mining

Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...

 shafts in salt mines. It is composed of 16% cement

Portland cement

Portland cement is the most common type of cement in general use around the world because it is a basic ingredient of concrete, mortar, stucco and most non-specialty grout...

, 39% halite

Halite

Halite , commonly known as rock salt, is the mineral form of sodium chloride . Halite forms isometric crystals. The mineral is typically colorless or white, but may also be light blue, dark blue, purple, pink, red, orange, yellow or gray depending on the amount and type of impurities...

, 16% limestone

Limestone

Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

 powder, 14% water

Water

Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...

 and 15% sand.

History

Salt-concrete was used for the first time in 1984 in the Kali

Kali

' , also known as ' , is the Hindu goddess associated with power, shakti. The name Kali comes from kāla, which means black, time, death, lord of death, Shiva. Kali means "the black one". Since Shiva is called Kāla - the eternal time, Kālī, his consort, also means "Time" or "Death" . Hence, Kāli is...

 mine in Rocanville in Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

. A salt-concrete seal was also installed in the Asse II mine in Lower Saxony

Lower Saxony

Lower Saxony is a German state situated in north-western Germany and is second in area and fourth in population among the sixteen states of Germany...

 in 1995.

Filling tunnels

Since the end of the repository for radioactive waste Morsleben

Repository for radioactive waste Morsleben

The repository for radioactive waste Morsleben is a deep geological repository for radioactive waste in the rock salt mine Bartensleben in Morsleben, district Börde in the federal state Saxony-Anhalt.-History:...

 in 1998, the salt dome

Salt dome

A salt dome is a type of structural dome formed when a thick bed of evaporite minerals found at depth intrudes vertically into surrounding rock strata, forming a diapir....

 stability deteriorated to a state where it could collapse. Since 2003, a volume of 480.000 m³ of saltconcrete has been pumped into the pit to temporarily stabilize the upper levels. In addition another 4.000.000 m³ of saltconcrete will be used to temporarily stabilize the lower levels.

See also

• Friedel's salt
  Friedel's salt
  Friedel's salt is an anion exchanger mineral belonging to the family of the layered double hydroxides . It has affinity for anions as chloride and iodide and is capable to retain them to a certain extent in its crystallographical structure....
  
  
  • synthesized first by Georges Friedel
    Georges Friedel
    Georges Friedel was a French mineralogist and crystallographer.- Life :Georges was the son of the famous chemist Charles Friedel...
    
    
• Sorel cement
  Sorel cement
  Sorel cement is a non-hydraulic cement first produced by Frenchman Stanislas Sorel in 1867.The cement is a mixture of magnesium oxide with magnesium chloride with the approximate chemical formula Mg4Cl268, corresponding to a weight ratio of 2.5–3.5 parts MgO to one part MgCl2...
  
  
  • produced first by Stanislas Sorel
    Stanislas Sorel
    Stanislas Sorel was a French engineer, raised the son of a poor clock-maker.Sorel filed a patent on 10 May 1837 for a "galvanic" method of protecting iron from rust by either coating it in a bath of molten zinc or by covering it with galvanic paint...
    
    
• Saltcrete
  Saltcrete
  Saltcrete is a mixture of cement with salts and brine, usually originating from liquid waste treatment plants. Its role is to immobilize hazardous waste and in some cases lower-level radioactive waste in the form of solid material. It is a form of mixed waste....