海绵铁还原水中硝酸盐的初步研究

Preliminary Study on Reduction of Nitrate in Water with Sponge Iron

研究了海绵铁还原水中硝酸盐的各项性能.通过单因素的影响试验,讨论了pH、进水硝酸盐浓度、粒径及添加锰砂对硝酸盐还原效果的影响.结果表明,当pH值为5时1 g海绵铁反应60 min还原硝酸盐的量为0.30 mg;小粒径有利于海绵铁还原硝酸盐;进水硝酸盐浓度在11～220 mg/L范围内,海绵铁还原硝酸盐的量呈先上升后趋于平缓之状;锰砂的添加使海绵铁还原硝酸盐的量增加了约1倍.还通过电镜扫描观察了不同pH值下海绵铁在反应前后的表观变化,这为进一步的研究提供了理论依据.

Difierent performances of nitrate reduction in water with sponge iron were studied. The effects of pH, nitrate concentration of influent, particle size and addition of manganese sand on denitrification were discussed by one-factor experiment. Results show as follows ： 0.30 mg nitrate is reduced by per g sponge iron after reaction time of 60 min at pH 5 ; Small particle sponge iron is favorable to reduce the concentration of nitrate; The nitrate reduction by per g sponge iron gradually increases with its influent concentration from 11 to 220 mg/L; However, variable tendency of nitrate reduction per g becomes stable when the nitrate concentration is over 220 mg/L; The amount of nitrate reduced by sponge iron is doubled with the addition of manganese sand. The apparent variations of sponge iron were investigated by scanning electron microscopy at different pH before and after reaction, and this will provide theoretical basis for further research.