A METHOD FOR TREATING A WASTE CONTAINING SULFURIC ACID
    5.
    发明公开
    A METHOD FOR TREATING A WASTE CONTAINING SULFURIC ACID 审中-公开
    一种处理含硫酸废物的方法

    公开(公告)号:EP3212577A1

    公开(公告)日:2017-09-06

    申请号:EP15825628.9

    申请日:2015-10-27

    摘要: A method for treating a waste material (20) containing sulfuric acid and metal ions, as In the case of the waste material the production of the T1O2, provides mixing to the waste material (20) an alkaline reagent (10), selected among a hydroxide of an alkaline metal such as Mg, Zn, Sn, adapted to selectively precipitate (300) the cations as hydroxides, thus obtaining a first mixture (21) having a higher pH that contains a solution (22) of a sulfate and/or oxysulfate of the metal and solid hydroxides (23) of the metal cations that are separated from the first mixture (21) and can be used in metal sulfates production process. The method also comprises mixing the solution (22) with a precipitation agent (31), thus forming a second mixture (32) in which the sulfate and/or oxysulfate precipitates and is removed (301), heated, reduced and decomposed (400) by means of a reducing agent (41) selected among elemental sulfur, hydrogen and a reducing flame, thus obtaining SO
    2 (42) available for making H
    2 SO
    4 , and a solid oxide (43) of the metal of the alkaline reagent that is recycled (101) as alkaline reagent (10) in the step (200) of mixing with the waste material (20). Advantageously, a step (350) is provided of recovering precipitation agent (31) from the water of second mixture (32), after removing (301) the sulfate and/or oxysulfate, and a step (351) is also provided of recycling the regenerated precipitation agent (31), In particular, an alcohol as ethyl alcohol, used as the precipitation agent (31), can be easily regenerated by distillation, exploiting low temperature-heat, which is largely available from a possible sulfuric acid production plant close to the plant that producing the sulfuric waste material (20). The method according to the invention makes it possible to eliminate the sludge resulting from the sulfuric waste material treatment, while recovering valuable compounds.

    摘要翻译: 一种用于处理含有硫酸和金属离子的废料(20)的方法,如在生产TiO 2的废料的情况下,向废料(20)提供碱性试剂(10)的混合,碱性试剂(10)选自 (Mg),锌(Zn),锡(Sn)等碱金属的氢氧化物,适于选择性地沉淀(300)阳离子作为氢氧化物,从而获得具有较高pH的第一混合物(21),其含有硫酸盐溶液(22)和/或 金属阳离子的金属硫酸盐和固体氢氧化物(23),其与第一混合物(21)分离并且可用于金属硫酸盐生产过程。 该方法还包括将溶液(22)与沉淀剂(31)混合,由此形成第二混合物(32),其中硫酸盐和/或硫酸盐沉淀并被去除(301),加热,还原和分解(400) 借助于选自元素硫,氢和还原火焰的还原剂(41),从而获得可用于制备H 2 SO 4的SO 2(42)以及被再循环的碱性试剂的金属的固体氧化物(43)(101 )作为与废物(20)混合的步骤(200)中的碱性试剂(10)。 有利地,提供在去除(301)硫酸盐和/或硫酸盐之后从第二混合物(32)的水中回收沉淀剂(31)的步骤(350),并且还提供步骤(351) 再生沉淀剂(31),特别地,作为沉淀剂(31)使用的作为乙醇的醇可以容易地通过蒸馏再生,利用低温度热量,其可以从可能的硫酸生​​产厂关闭 到生产硫酸废料(20)的工厂。 根据本发明的方法可以消除由硫酸废料处理产生的污泥,同时回收有价值的化合物。