摘要
通过模拟试验,研究了沸石和方解石复合覆盖层控制底泥氮磷释放的效果及机理。结果表明,(1)Ca2+会促进方解石对磷酸盐的去除,并且Ca2+浓度越高,对磷酸盐去除的促进作用越强,而Na+则会抑制方解石对磷酸盐的去除。(2)采用CaCl2对天然沸石进行改性,可以提高沸石Ca2+的交换量和降低Na+的交换量;而采用NaCl改性则可以明显提高沸石Na+的交换量,并且大幅度地降低沸石Ca2+的交换量。(3)沸石与方解石复合覆盖层不仅可以控制底泥氨氮的释放,而且可以抑制底泥磷的释放,并且复合覆盖层对底泥磷释放的控制效果受沸石改性的影响,控制效果从大到小依次为CaCl2改性沸石>天然沸石>NaCl改性沸石。
Efficiency and mechanics of compound barrier with calcite and zeolite to immobilize phosphorus and nitrogen release from sediments were researched. The results show that： （1） The efficiency of phosphorus removal by calecite was promoted by Ca^2＋ but inhibited by Na^＋, and the more the Ca^2＋, the more the efficiency of phosphorus removal by calcite. （2） In comparison to natural zeolite, more Ca^2＋ and less Na^＋ of CaCl2 modification zeolite exchanged with NH4^＋ in solution, while, less Ca^2＋ and more Na^＋ of NaCl modification zeolite exchanged with NH4^＋ in solution. （3） The compound barrier with zeolite and calcite not only controlled the ammonia release from sediments, but also reduced the phosphorus release rate. The efficiency of this compound barrier to immobilize phosphorus release from sediments was influenced by zeolite＇ s inorganic salt modification, with the order： CaCl2 modification zeolite〉natural zeolite〉NaCl modification zeolite.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2007年第2期790-794,共5页
Journal of Agro-Environment Science
基金
科技部小城镇科技发展重大项目(2003BA808A17)
国家自然科学基金(50478103)
关键词
天然沸石
CaCl2改性沸石
NaCl改性沸石
复合覆盖层
底泥
氮磷
natural zeolite
CaCl2 modification zeolite
NaCl modification zeolite
compound barrier
, sediment
phosphorus and nitrogen
