模拟酸雨对羟基磷灰石稳定化污染土壤磷/镉释放的影响  

Effects of simulated acid rain on releases of phosphorus and cadmium in a contaminated soil immobilized by hydroxyapatite

作　　者：马凯强 崔红标[1,2] 范玉超[1] 苏彬彬[1] 胡友彪[1] 周静[2] 

机构地区：[1]安徽理工大学地球与环境学院,安徽淮南232001 [2]中国科学院南京土壤研究所,南京210008

出　　处：《农业环境科学学报》2016年第1期67-74,共8页Journal of Agro-Environment Science

基　　金：国家"973"计划课题(2013CB934302);安徽理工大学博士;硕士基金(11276);中国科学院"STS"项目(KFJ-EW-STS-016);国家科技支撑计划课题(2015BAD05B01)

摘　　要：通过室内土柱淋溶实验,以0.5%的质量比向镉污染土壤中添加羟基磷灰石（HAP）,考察p H值为3.5、4.5和5.6的模拟酸雨对土壤磷和镉释放的影响。结果表明：淋出液p H随着酸雨p H降低逐渐下降,HAP处理使淋出液p H较未处理土壤淋出液显著增加0.3~1.5个单位。淋出液总磷和正磷酸盐含量均随酸雨p H的降低而增加,且HAP处理显著增加了淋出液中总磷和正磷酸盐含量;总磷含量在第1~3 L和4~6 L分别是《地表水环境质量标准》（GB 3838—2002）五类水标准（总磷含量0.4 mg·L-1）的2.70~3.55倍和1.25~2.15倍,对地表水表现出较大的富营养化风险。较未处理土壤,HAP处理显著降低了淋出液中Cd含量,随酸雨p H降低,未处理土壤淋出液Cd含量逐渐增加,而HAP处理土壤淋出液Cd含量逐渐降低。因此,HAP能够显著减少酸雨淋溶对污染土壤中Cd的淋失,但需防止磷素释放造成地表水体富营养化。Releases of phosphorus and cadmium from a contaminated soil with and without hydroxyapatite treatment were studied under sim- ulated acid rain with pH of 3.5, 4.5 and 5.6. Results showed that leaching solution pH decreased ~with decreasing pH in simulated acid rain. However, leaching solution pH was 0.3-1.5 units higher in the hydroxyapatite treated soil than that in the untreated soil. The contents of to- tal phosphorus and orthophosphate in the leaching solution were both increased with decreasing pH in simulated acid rain. Total phosphorus Contentsat leaching amounts of 1 ~3 L and 4~6 L were 2.70~3.55 and 1.25~2.15 times higher than the class V limit （0.4 mg· L-1） of the Chinese National Quality Standards for Surface Waters （GB 3838--2002） respectively. The concentrations of Cd in the leaching solution decreased significantly in hydroxyapatite amended soil, compared with the untreated soil. The contents of Cd in the leaching solution in the untreated soil increased with the decreasing of pH of simulated acid rain, but they were much slower in the hydroxyapatite amended soil. Our results indicate that applications of hydroxyapatite could decrease the leaching loss of Cd effectively, but might have a potential risk of water eutrophication due to the high leaching loss of phosphorus.

关 键 词：模拟酸雨 羟基磷灰石 淋溶 磷 镉 

分 类 号：X53[环境科学与工程—环境工程]