骨料嵌锁型水泥-磷石膏基层材料的浸出毒性与环境影响研究

Study on Leaching Toxicity and Environmental Impact of Cement-phosphogypsum Stabilized Stone Interlocking Base Material

为了促进磷石膏的综合利用,定量评估磷石膏基层的环境影响。通过磷石膏部分取代细集料制备了一种骨料嵌锁型水泥-磷石膏稳定碎石路面基层材料,其浸出毒性进行研究,对该路面基层试验路段的淋溶液进行了环境影响分析。结果表明,骨料嵌锁型水泥-磷石膏基层可减少20%水泥用量,清洗、固化后的磷石膏浸出毒性更低,制备的路面基层材料的重金属离子浸出毒性也满足建筑材料的要求,在贵州省某二级路试验段边沟雨水的Cr^(6+)的浓度为0.011 mg/L,其它的重金属含量全部低于0.002 mg/L,除总磷含量之外,符合IV级地表水标准,在边沟雨水的稀释下不会对环境造成污染。

In order to promote the comprehensive utilization of phosphogypsum and quantitatively evaluate the environmental impact of phosphogypsum road base.A stone interlocking cement-phosphogypsum stabilized crushed pavement base material was prepared by partially replacing fine aggregates with phosphogypsum,and its leaching toxicity was studied,and the environmental impact analysis of the phosphorus solution in the test section of the pavement base was carried out.The results show that the stone interlocking cement-phosphogypsum base could reduce 20%of the cement amount,the leaching toxicity of phosphogypsum after cleaning and curing was lower,and the leaching toxicity of heavy metal ions of the prepared pavement base material also met the requirements of building materials.The concentration of Cr^(6+)in the rainwater of the side ditch in a secondary road test section of Guizhou Province was 0.011 mg/L,and the other heavy metal content was all less than 0.002 mg/L,except for the total phosphorus content,it met the IV grade surface water standard.It did not cause pollution to the environment under the dilution of rainwater in the side ditch.