| 摘要 |
The invention provides a method for removing polluting constituents from used oil by heating the used oil to an increased temperature below 100 DEG C; adding water to the oil; adding sulphuric acid to the oil; thoroughly mixing the oil and the sulphuric acid; allowing the oil-sulphuric acid mixture to stand; adding a demulsifier to the oil-sulphuric acid mixture; thoroughly mixing the oil-sulphuric acid-demulsifier mixture; allowing the oil-sulphuric acid-demulsifier mixture to stand in order to allow forming of a water phase containing the pollutants and a purified oil phase; and separating the water phase from the purified oil phase. The sulphuric acid is added to the oil to dissolve heavy metals present in the oil. The dissolved heavy metals come to lie in the water phase, further formation of water soluble metal compounds is performed by adding the demulsifier, which will result in separation of the water phase from the oil layer. After a treatment according to the invention the purified oil contains less than 0.1 % by weightheavy metals and is therefore suitable for combustion or for re-use for refining purposes. |
