1. 毕业设计（论文）的内容和要求

为了提高机械产品和零部件的硬度、耐磨性和抗腐蚀性，在加工制造的时候需要在碳钢产品表面镀上一层硬铬。

在镀铬工艺过程中，镀件喷淋清洗、电镀槽清洗、镀件退镀、跑冒滴漏和地面冲洗等环节都会产生高浓度的六价铬（铬（Ⅵ））废水。

由于含铬化合物尤其是铬（Ⅵ）毒性高、易被人体吸收，对生态环境和人体健康危害很大，世界各国都对含铬污染物制订了非常严格的排放限值。

2. 参考文献

[1] Gheju M, Balcu I. Removal of chromium from Cr(VI) polluted wastewaters by reduction with scrap iron and subsequent precipitation of resulted cations[J]. Journal of Hazardous Materials, 2011, 196(196):131. [2] Shi H, Li J, Shi D, et al. Combined Reduction/Precipitation, Chemical Oxidation, and Biological Aerated Filter Processes for Treatment of Electroplating Wastewater[J]. Separation Science Technology, 2015, 50(15):2303-2310. [3] Fang Z, Qiu X, Huang R, et al. Removal of chromium in electroplating wastewater by nanoscale zero-valent metal with synergistic effect of reduction and immobilization[J]. Desalination, 2011, 280(1#8211;3):224-231. [4] Chen S S, Hsu B C, Hung L W. Chromate reduction by waste iron from electroplating wastewater using plug flow reactor[J]. Journal of Hazardous Materials, 2008, 152(3):1092-1097. [5] Chen S S, Cheng C Y, Li C W, et al. Reduction of chromate from electroplating wastewater from pH 1 to 2 using fluidized zero valent iron process[J]. Journal of Hazardous Materials, 2007, 142(1-2):362.

3. 毕业设计（论文）进程安排

见附件。