为研究酸碱溶液对尾矿砂含水率和重金属含量的影响,采用室内土柱动态淋溶的方法,对采自阜新同乃矿尾矿坝的尾矿进行实验,测得不同pH溶液动态淋溶后的尾矿砂含水率,并应用火焰原子吸收光谱法,测出尾矿砂中6种重金属元素在淋溶后的含量,结果表明:①经酸碱溶液淋溶后尾矿砂土体的含水率出现增加的现象;②淋溶液pH从4增加到7时,Cu和Cr的含量逐渐减少,淋溶液pH从7增加到10时,Cu和Cr的含量逐渐增加;相反Mn和Ni的含量先随pH的增加而增加,在pH大于8和8.5左右开始降低;Fe含量出现略微减少的趋势;Cd含量在淋溶液pH 4~6.5范围内逐渐增加,而后含量降低。文中淋溶液选择的是酸碱溶液而不是纯净水,所以用此结果描述尾矿库的环境和安全情况更具有实际意义。
In order to evaluate the effect of acid and alkali solutions on water and heavy metal con- tents of tail ore, experiments using the method of dynamic leaching of soil column with tail ore col- lected from Tongnai tailing dam in Fuxin, Liaoning of China, were performed. It was found that wa- ter content increased after leaching but metals of Cu, Cr, Mn, Cd and Ni respoused differently to the pH of the leaching solution in the range of pH 4 to pH 10. The contents of Cu and Cr decrease as the pH of the leaching solution increase from pH 4 to about pH 7, but increase when the solution pH is greater than 7 ; the contents of Mn and Ni increase as the solution pH increase but decrease slightly when the pH is greater than 8.5 and 8, respectively ; Fe content decreases steadily as the so- lution pH increases, while the Cd content increases as the solution pH increases from 4 to 6. 5, then decrease sharply when solution pH exceed this point. Since the leaching solution is acidic or alkalic, it is more meaningful than the pure water in describing the actual environment of tailings.