Using Calcium Carbonate/Hydroxide and Barium Carbonate to Remove Sulphate from Mine Water

Review of Remediation Solutions for Acid Mine Drainage Using the Modified Hill Framework

“…In the chemical desalination process, the pH is increased sequentially using alkaline reagents and calcium sulphide compounds leading to neutralisation and metal precipitation as metal sulphides and metal hydroxides. Lime or Mg(OH) 2 and barium-containing compounds, typically BaCO 3 or Ba(OH) 2 , are then dosed to raise the pH above 10 with adequate retention time allowed for the reaction, resulting in the precipitation of highly soluble metals Mg, Mn, Ni and Cd as metal hydroxides and the precipitation of SO 4 as BaSO 4 [5,50,51]. A variation is the use of calcium sulphide (CaS) with lime to increase the pH to above 10 and the precipitation of metals as hydroxides and sulphides [32,49,52].…”

“…Chemical Desalination HDS processes are still limited to low treated water quality, which has prom further advancements in chemical treatment technologies through the developmen deployment of chemical desalination processes such as the CSIR Alkaline-Barium cium (ABC) process and the Magnesium-Barium-Hydroxide (MBO) process [5,32,4 the chemical desalination process, the pH is increased sequentially using alkaline rea and calcium sulphide compounds leading to neutralisation and metal precipitati metal sulphides and metal hydroxides. Lime or Mg(OH)2 and barium-containing pounds, typically BaCO3 or Ba(OH)2, are then dosed to raise the pH above 10 with quate retention time allowed for the reaction, resulting in the precipitation of highl uble metals Mg, Mn, Ni and Cd as metal hydroxides and the precipitation of SO4 as B [5,50,51]. A variation is the use of calcium sulphide (CaS) with lime to increase the p above 10 and the precipitation of metals as hydroxides and sulphides [32,49,52].…”

Recent developments in materials used for the removal of metal ions from acid mine drainage

“…Adsorption is a versatile technique, in the sense that the adsorbent can be restored and subsequently re-used without reducing the removal efficiency (Bai et al 2017). A range of adsorbents for treatment of AMD have been used, which include high density sludge (Sukati et al 2018;Dlamini et al 2019), alkali-barium-calcium (Mulopo and Motaung 2014;Akinwekomi et al 2017), coal fly ash (Rios et al 2008;Madzivire et al 2019) and lignite (Mohan and Chander 2006;Karagüzel et al 2020). Among the studied adsorbents is activated carbon (Hong et al 2017), silica (Etale et al 2016;Lakovleva and Sillanpää 2013) and ferric oxide (Dlamini et al 2019).…”

Selective Separation of Sulfate and Chloride Ions from Industrial Wastewater by In Situ Generation of CaFe-Layered Double Hydroxides and the Related Resource Utilization

“…Traditional chemical precipitation method usually uses barium and calcium salts to achieve SO 4 2– precipitation . However, the barium salt precipitation has the problems of high cost and high toxicity . The lime precipitation is limited by the high solubility of calcium sulfate (p K sp = 3.70), so SO 4 2– cannot be efficiently removed and meet the relevant standards. , Apart from that, the disadvantage of resource wastage of the coprecipitation method has not been addressed.…”