摘要
通过室内模拟土柱淋溶实验,研究了不同pH值(3.1,4.1,6.5)的酸雨下,改性沸石用于控制污染土重金属Pb、Zn的淋溶效果。结果表明,淋溶过程中,酸雨pH值越小,改性沸石剂量越高,淋滤液的pH值相对越大,且酸雨pH值的降低并没有引起Pb、Zn淋溶总量的显著增加;不同pH和不同剂量改性沸石下,Pb的淋溶总量要明显大于Zn的淋溶总量;相比于空白剂量(0g/kg)沸石,高剂量(100g/kg)改性沸石和低剂量(20g/kg)改性沸石均能显著降低Pb和Zn的淋溶总量,且两者所起效果相差不大,其中,酸雨pH值为3.1,4.1和6.5时,对添加低剂量沸石,Pb的淋溶总量分别降低28.7%,34.8%和40%,而Zn的淋溶总量分别降低48.5%,53.9%和45.5%。研究结果表明,天然沸石经过一定方法改性后,可以有效防止酸雨条件下污染土壤重金属Pb和Zn的淋溶流失。
The indoor soil column leaching experiment was conducted to study the leaching effects of modified zeolite on Pb and Zn in contaminated soil under simulated acid rain with the pH values of 3.1, 4.1 and 6.5. The results showed that, with the lower pH of the acid rain and the higher dosage of the modified zeolite, the pH of the leachate was relatively higher and the pH decrement of the acid rain did not cause the signifi- cant increase of total content of Pb and Zn. Under the different pH of the acid rain and different dosages of modified zeolite, the total leaching amount of Pb was significantly greater than that of Zn. Compared with the blank group（0 g/kg）, the high dosage（100 g/kg） and low dosage（20 g/kg） of the additive modified zeolite could significantly decrease the total leaching amount of Pb and Zn, but with no obvious differences between them. The low dosage of the modified zeolite could reduce the leaching amount of Pb by 28.7%, 34.8% and 40%, and of Zn by 48.5%, 53.9% and 45.5% under the simulated acid rain with the pH of 3.1, 4.1 and 6. 5. The results indicated that the modified zeolite could prevent the leaching of Pb and Zn in contaminated soil under acid rain.
出处
《水土保持学报》
CSCD
北大核心
2015年第5期304-308,共5页
Journal of Soil and Water Conservation
关键词
土壤
沸石
酸雨
铅
锌
淋溶
soil
zeolite
acid rain
lead（Pb）
zinc（Zn）
leaching
