磷矿废石固化体力学特性及固磷效果试验研究

Experimental study on mechanical characteristics of cured body of waste rocks of phosphate and the effect of cured phosphorus

为缓解磷矿废石中磷元素流失对生态环境造成的危害,以湖北省宜昌市兴山县树空坪磷矿区磷矿废石为研究对象,基于EPA M1315试验规范,开展不同水泥含量条件下磷矿废石固化体抗剪强度试验及固磷效果试验.结果表明:粘聚力与水泥质量分数之间呈较好的线性相关性,随着水泥质量分数的增加,试样的抗剪强度增大;A1试样浸滤液的p H值最大,为10.23,F6试样浸滤液和H8试样浸滤液的p H值最小,为8.41,最接近中性,对土壤和河流的酸碱危害性最小;H8试样浸滤液的总磷浓度累计释放量最大,为5.09 mg/L,F6试样浸滤液的总磷浓度累计释放量最小,为2.31 mg/L.因此,F6试样的固磷效果最好,即磷矿废石固化材料的最优配比为水泥质量分数50%(百分比针对磷矿废石质量而言)、粉煤灰质量分数10%、粘土质量分数40%.

In order to alleviate the harm to the ecological environment caused by the loss of phosphorus in waste rocks of phosphate, on study of the waste phosphate rock of Xingshan County, Yichang City, Hubei Province Kong Ping Phosphate mine, based on EPA M1315 test specifications, this paper carried out the test of shear strength of waste rocks of phosphate and the effect of cured phosphorus under different conditions of cement content. The results show that a good linear correlation is between cohesion and cement content. With the increase of cement content, the shear strength of the samples increases. p H value of the sample A1＇s filtrate is the biggest of 10.23, and p H value of the sample F6＇s filtrate is the smallest of 8.41, closest to neutral that is the minimum harm to the p H of soils and rivers. The accumulated release amount of total phosphorus concentration of the sample H8 is the biggest of 5.09 mg/L and The accumulated release amount of total phosphorus concentration of the sample F6 is the smallest of 2.31 mg/L. Therefore, the best effect of phosphorus fixation is the sample F6, in which optimal ratio of waste phosphate rock solidifying material is 50% of cement（the percentage in terms of waste rocks of phosphate quality）, 10% of coal mass, and 40% of clay.