| Chromium and its compounds have been used in most industrial departments, which have produced a great number. Wastewater containing Cr is easily dissolved with the rainwater, which could pollute the soil, river and underground water source. There are mainly two kinds of existence forms of chromium in the wastewater, Cr (VI) and Cr (III). In the chemical compound of chromium, Cr (VI) has the strongest toxicity and then Cr (III). Therefore, a simple, effective and economic method is urgently needed to the treatment of waste residue and wastewater.There are many kinds of technologies in treating the wastewater containing chromium, according to the properties of wastewater containing Cr which came from the silicon steel plant in Iron and Steel Group, using reduction-precipitation treated wastewater containing chromium. Exploring the pH value of the Reaction, the dosage of the Reluctant, reaction time and precipitated conditions of trivalent chromium. The interaction effects of different facts were researched with orthogonal experiments, and the sludge containing chromium was been utilization, studying the conditions of producing Cr2O3 with the sludge containing chromium, The results showed that the removal rates of chrome, turbidity, hexvalent chromium, total chromium were respectively 98.5%,91.32%,99.27%,95.43% by using the angent of sodium bisulfite, when the pH was 3, reagent dosage was 0.7994g/L, the time was 15min. With the 840℃and 1.0h reacting time, chromium hydroxide had been decomposed, the content of milori green reached 94.68%.
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