Rendering safe the waste from polishing barium-glass - by treating with aq. suspension of calcium sulphate to precipitate barium ions as sulphate

摘要

Ba ions in waste materials, esp. grits from surface-working Ba-contg. glass, are bonded by treating the waste with an aq. suspension of a water-insoluble sulphate cpd. The insoluble sulphates bond the released Ba ions as BaSO4. The process allows the deposition of toxic Ba-contg. waste on waste tips. The waste is pref. treated with =1 kg anhydrous CaSO4/kg Ba ions in waste. Anhydrous CaSO4 also acts as a lubricant and filtration aid and increases water-hardness, which is advantageous when using the water for glass polishing.