pH值对含铬废水处理效果的影响研究

研究彩色显像管总装车间含铬废水处理过程中,pH值对Cr6+还原效果的影响,采用能斯特方程计算pH值分别为7和2时的Cr6+还原为Cr3+的氧化还原反应电位,结果表明,在pH值为7时电位差比pH值为2时大,更有利于Cr6+还原为Cr3+,并通过试验证实了这个结果。从而改进了含铬废水处理工艺,减少了工艺步骤,节省投资15万元左右。每年可节约酸碱费用6.18万元。年少向水体排放盐分198 t。

Influence of pH value on effect of chromium-containing wastewater treatment

The effect of pH value on the deoxidization of Cr6 when treating chromium-containing wastewater from CPT assembly workshop was investigated,and the electric potential of the redox reaction which deoxidize Cr6 into Cr3 with pH value of 7 and 2 were calculated using Nernst formula respectively.The results showed that,the electric potential difference was larger with pH 7 than with pH 2,thus benefited the transfer of Cr from Cr6 to Cr3 ,and the above results has been confirmed through the test.It can draw a conclusion that,treating chromium-contain-ing wastewater under proper pH conditions optimize the process,reduce the process step,and save about 150 000 yuan of investment.The expense on the acid and alkali can be saved by 61 800 yuan every year,and the salinity discharged into water body is reduced 198 ton every year.