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【正文】 渣中加入硫化鈉、硫氫化鈉等進(jìn)行!$的還原反應(yīng),硫化鈉解毒機(jī)理如下:8Na2CrO4+6Na2S+23H2O8Cr (OH )3+3Na2S2O3+22NaOHCr3+形成Cr(OH)3,沉淀后,過(guò)濾回收鉻污泥。更甚者鉻(Ⅵ)有致癌作用,致癌的部位主要是肺,已確認(rèn)為是致癌物,并能在人體內(nèi)積蓄。這些病變大都是慢性的,因此常常一時(shí)覺(jué)察不出來(lái),待發(fā)現(xiàn)后,病程已經(jīng)有了相當(dāng)?shù)陌l(fā)展。鉻渣屬于粘性上,粘結(jié)力強(qiáng),容易板結(jié),分散性差。二、鉻渣的形成與危害鉻渣是指在鉻鹽生產(chǎn)中,鉻鐵礦與純堿、石灰輔料等混合高溫鍛燒,用水浸取生成鉻酸鈉后所剩余的殘?jiān)?。中?guó)年排放鉻渣約20萬(wàn)t,迄今堆存的鉻渣已超過(guò)300萬(wàn)t。關(guān)鍵詞:鉻渣 危害 無(wú)害處理 資源利用Abstract:There will arise a mass of chromiumcontaining residue in the production process of chromium and chromic salts. There are plenty of CaO, MgO, Fe2O3in chromiumcontaining residue, which can replace limestone anddolomite for industrial production, so the resources are saved and the energy expenditure is reduced. Chromiumcontaining residues are dangerous waste that seriously pollute the ecological environment and harm the humanhealth due to the big output and fierce toxicity. The present processing situation of chromiumcontaining residuesby sintering and ironmaking in our steel enterprises is introduced, and disintoxicating mechanism, technologicalprocess and application practice are analyzed. The way and prospect of prehensive utilization of chromiumcontaining residues in the ferrous metallurgy process are elaborated, and the proposal is put forw
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