Study on using fly ash treatment of high concentrations fluoride wastewater | 改性粉煤灰处理高质量浓度氟离子废水的初步研究

Chinese. 针对目前排放废水中含氟量严重超标问题，研究粉煤灰粒径、改性方式对废水中氟离子吸附效果的影响，为高质量浓度氟离子废水的处理提供理论依据。以粉煤灰为吸附材料，1 mol/L盐酸或1 mol/L氢氧化钠为改性剂，采用单因素试验和L25(56)正交试验，研究不同因素对废水中氟离子去除率的影响。当粉煤灰粒径0.15 mm时，其对废水中氟离子去除效果最佳；用1 mol/L盐酸改性粉煤灰对含氟废水的处理效果比1 mol/L氢氧化钠好；正交试验结果表明，当改性粉煤灰添加量为15.0 g，吸附时间为90 min，聚丙烯酰胺（PAM）（质量分数1%）用量为0.05 mL，pH为4.0，吸附温度为45 ℃时，去除废水中氟离子效果最佳，对含1 000 mg/L氟离子废水的去除率可达86.7%。得到了改性粉煤灰处理高质量浓度氟离子废水的最佳条件，改性粉煤灰有望成为一种良好的含氟废水处理剂。

English. As the fluoride content of discharge wastewater for plants excessively exceeds the standard, this study investigated the particle size, different modification methods and related factors on the effects of the absorption efficiency of fluoride ion by fly ash in discharge wastewater to provide theoretical and methodological basis to the treatment of high concentrations fluoride ion wastewater. In the batch experiment, using fly ash as absorbent material, 1 mol/L HCl or 1 mol/L NaOH as the modifier, single test and L25(56) orthogonal test were used to study the various factors on the wastewater to the fluoride ion removal rate. The results showed that the removal of fluoride ion could obtain the best efficiency when the fly ash diameter was less than 0.15 mm; 1 mol/L HCl modified fly ash was more efficient than that of 1 mol/L NaOH on the Fluorine containing wastewater treatment; orthogonal test showed that when the modified fly ash dosage was 15.0 g, absorption time 90 min, polyacrylamide (PAM) (concentration of 1%) dosage 0.05 mL, pH at 4.0, and the absorption treatment temperature 45 ℃, the removal of fluoride ions in waste water is best 86.7% removal rate can be achieved to for wastewater containing 1 000 mg/L fluorideions. The best conditions to modified fly ash of high concentration fluoride wastewater is obtained, the modified fly ash is expected to be a good absorbent for clean and high concentration fluoride wastewater.