| 摘要 |
<p>Calcium fluoride fines or residues comprising calcium fluoride fines, e.g. residues from treating waste water or waste gas, e.g. originating from HF or fertilizer production, with calcium oxide or calcium carbonate to remove HF or fluorides can be converted to HF and calcium sulfate by reaction with sulfuric acid in the form of a suspension. Unreacted calcium oxide or calcium carbonate generates sufficient heat to the endothermic reaction between calcium fluoride and sulfuric acid so that no external heat is needed.</p> |
