Discover the multiple functionalities of lime and minerals

Wastewater and Sludge


Minerals correct the acidity of water or effluents by adjusting their pH either closer to neutrality (pH = 7) or to a given pH target. Natural waters containing excessive carbon dioxide (CO2) compared to equilibrium are aggressive. The excessive CO2 can be neutralized by adding carbonate-based products to recover the water’s pH equilibrium.

Lhoist products help preserve the environment, via the:

  • prevention and treatment of Acid Mine Drainage, by neutralizing acid and further preventing leaching of heavy metals into groundwater.
  • neutralization of post-mining acid lakes and ponds.

Coagulate, flocculate

Fine suspended solids in water can be agglomerated and removed by coagulation and flocculation using agents such as lime, FeCl3 and polymers.


Heavy metals are less soluble in water in specific pH ranges, where they form precipitates. Other ions such as sulfates, phosphates or fluorides can also be eliminated from water by adjusting its pH.