| 摘要 |
A process for phosphorous removal from iron ore or phosphorous recovery from phosphorous ore, in which the phosphorous is leached out of the ore with hydrochloric acid HCl or nitric acid HNO3, preferably HNO3, as leaching acid and then phosphoric acid and leaching acid are extracted out of the leaching solution obtained by this means in a liquid- liquid extraction step 5 and thereby transferred to a phase immiscible with water, such as an organic phase and then the phosphoric acid and leaching acid are re-extracted out of the organic phase in a liquid-liquid extraction step 8, stripping step 8 and thereby transferred to an aqueous phase, whereafter the phosphoric acid and leaching acid are separated by for example evaporation. The process is distinguished in that the leaching solution, out of which the phosphoric acid and leaching acid are extracted, in a precipitation step 1 is treated with sulphuric acid, whereby the leaching acid is re-formed and gypsum is precipitated, whereafter the re-formed leaching acid can be re-used for leaching in the process. <IMAGE> |
