Regeneration of barium carbonate from barium sulphide in a pilot-scale bubbling column reactor and utilization for acid mine drainage

• Published in: Water science and technology Vol. 65; no. 2; pp. 324 - 331
• Main Authors: Mulopo, J, Zvimba, J N, Swanepoel, H, Bologo, L T, Maree, J
• Format: Journal Article
• Language: English
• Published: England IWA Publishing 2012
• Subjects: Acid mine drainage; Barium; Barium - chemistry; Barium Compounds - chemistry; Bubbling; Calcium; Carbon dioxide; Carbon Dioxide - chemistry; Carbonates; Carbonates - chemistry; Carbonation; Coal Mining; Desalination; Feasibility studies; Flow rates; Flow velocity; Industrial Waste; Mine drainage; Pilot Projects; Process parameters; Reactors; Regeneration; Regeneration (biological); Removal; Slurries; Sulfates; Sulfates - chemistry; Sulfides; Sulfides - chemistry; Sulphides; Technical feasibility; Waste Disposal, Fluid - methods; Water desalting; Water pollution
• ISSN: 0273-1223; 1996-9732
• DOI: 10.2166/wst.2012.857

Batch regeneration of barium carbonate (BaCO(3)) from barium sulphide (BaS) slurries by passing CO(2) gas into a pilot-scale bubbling column reactor under ambient conditions was used to assess the technical feasibility of BaCO(3) recovery in the Alkali Barium Calcium (ABC) desalination process and its use for sulphate removal from high sulphate Acid Mine Drainage (AMD). The effect of key process parameters, such as BaS slurry concentration and CO(2) flow rate on the carbonation, as well as the extent of sulphate removal from AMD using the recovered BaCO(3) were investigated. It was observed that the carbonation reaction rate for BaCO(3) regeneration in a bubbling column reactor significantly increased with increase in carbon dioxide (CO(2)) flow rate whereas the BaS slurry content within the range 5-10% slurry content did not significantly affect the carbonation rate. The CO(2) flow rate also had an impact on the BaCO(3) morphology. The BaCO(3) recovered from the pilot-scale bubbling column reactor demonstrated effective sulphate removal ability during AMD treatment compared with commercial BaCO(3).