生物-化学联合法去除地下水中硝酸盐

采用添加锯末和零价铁的土柱实验,比较了不同填料组成和不同填装方式对硝酸盐去除的影响,初步考察了生物-化学联合法去除水溶液中硝酸盐的效果.结果表明,同时添加锯末和铁粉比单独加锯末或铁粉的脱氮效果好;而只加堆肥腐熟后的锯末比只加锯末的脱氮效果好;只加锯末或堆肥锯末的效果比只加零价铁的好;增加锯末和零价铁的量都有助于硝酸盐的去除,而同时添加活性碳更有助于硝酸盐的去除.此外,填料的不同放置方式对硝酸盐去除有一定影响.在所有处理中,同时加了锯末和铁粉的出水中NO-2-N和NH 4-N浓度最低.这表明生物-化学联合法是一种很有前景的脱氮方法.

A combination biological and chemical approach for nitrate removal from groundwater

There are many reports about biological denitrification and chemical denitrification by Fe0 both here and abroad, but the combination of biological and chemical approaches have been rarely reported. Denitrification experiments were conducted in laboratory columns packed with sawdust and zero-valent iron (ZVI) to investigate the effects of different packing components and different packing modes on nitrate reduction. The results showed that the reactor packed with ZVI and sawdust had a better performance than the reactor packed with sawdust or ZVI alone. And the reactor packed with composted sawdust had a higher nitrate removal efficiency than the one packed with sawdust. The reactor packed with composted sawdust or sawdust had better performance than the one with Fe0 alone. Moreover, increasing the amount of sawdust and ZVI or adding active carbon could increase the denitrification effects. Different packing modes had different influences on denitrification. Little nitrite or ammonium was detected in the effluent of the reactor containing both sawdust and Fe0. So it indicated that the combination of biological and chemical approaches is a promising method for nitrate removal from groundwater.