生物除铁锰滤料再利用除氟试验研究

Study on reusing media from iron and manganese biological removal filter for defluoridation

生物除铁锰滤层定期更换的滤料可实现再利用。将表面孔隙发达的成熟石英砂滤料在110℃下烘干,检测并分析其再利用除氟的特点和方式,结果表明:试验条件下,生物除铁锰滤料再利用除氟吸附时间约为3 h,吸附速率符合二级反应速率模型;p H值在3~7之间时,滤料再利用除氟效果较好,p H=4.58时效果最佳;其除氟方式以化学作用为主,兼有物理吸附作用,吸附等温线符合Langmuir模型;动态试验证实利用生物除铁锰滤料再利用除氟是可行的。

The filter media from iron and manganese biological removal filter which was replaced regularly could be reused. The sand filter media with developed interspaces was characterized using the SEM. Drying the sand filter media at 110 ℃, its characteristics and mode of defluoridation were inspected and analyzed. The results showed that under the test condition, the adsorption balance could come out in about 3 h, the fluoride sorption on the reused matured filter media could accord with pseudo- second kinetics. The effect of defluoridation by the matured filter media would be better within the range of pH 3 to 7, and the effect was optimal when pH was 4.58. The primary mode of defluoridation was chemistry, but physical sorption was also in existence, and the adsorption isotherms could be described by Langmuir equation. Dynamic experiment proved that defluoridation by the filter media from iron and manganese biological removal filter was possible.