Synergistic effects of acid-treated rice bran and desulfurization gypsum on soil formation of bauxite residue
Soil formation of bauxite residue is the valid way to reduce the environmental risk and large-scale consumption.The present study investigated the effects of leaching solution and leachate from acid-treated rice bran synergized with desulfurization gypsum on soil formation of bauxite residue using an acid leaching method with phytic acid.The results show that the pH and EC of the bauxite residue decrease from 10.56 and 169.67 μS/cm to 8.42 and 75.53 μS/cm,respectively,after treatment by acid-treated rice bran(2%)and desulfurization gypsum(2%)for 30 d.The content of Na2O in alkaline mineral also decreases,while the proportion of large aggregates,non-capillary porosity,total organic carbon(TOC),and available phosphorus(AP)increases.Furthermore,the growth of ryegrass is improved.Cations of Al3+,Fe3+,Ca2+and Mg2+form insoluble chelates with phytic acid,thereby obviously reducing the cationic stress of plants.The Ca2+cation dissolved from desulfurization gypsum can accelerate the dealkalization efficiency,promote phytate decomposition,and increase TOC and AP contents while reduce the addition of rice bran.
bauxite residueacid-treated rice brandesulfurization gypsumphytic acidplanting soil for greening
万方数据
维普
