摘要
采用化学还原法制备纳米四氧化三铁,与聚合氯化铝(PAC)制备MFPAC磁性混凝剂,利用混凝沉淀-矿化垃圾吸附预处理垃圾渗滤液,用单因素变量法确定实验的最佳运行参数。结果表明:MFPAC磁性混凝剂对COD和色度的去除效果优于单独投加混凝剂PAC,在纳米四氧化三铁与PAC的质量比为1∶3、MFPAC的投加量为1.5 g·L^(-1)、搅拌条件为转速为300 r·min-1下搅拌60 s、溶液pH值为7.5(垃圾渗滤液原水的pH值)、絮凝时间为30 min的最佳运行条件下,COD由5 810 mg·L^(-1)降低到2 173 mg·L^(-1),色度由1 658倍降低到556倍,其COD去除率为62.6%,色度去除率为66.5%;利用矿化垃圾作为吸附剂处理MFPAC混凝处理后的出水,在矿化垃圾粒径小于2 mm、焙烧温度为700℃、吸附剂投加量为40 mg·L^(-1)、pH值为9的最佳条件下,经过12 h的处理,COD和氨氮的去除率分别为56.7%和68.4%,最终出水的COD和氨氮的浓度分别为941 mg·L^(-1)和343 mg·L^(-1);最终,MFPAC混凝沉淀-矿化垃圾吸附工艺对垃圾渗滤液COD、色度和氨氮的去除率分别为83.8%、78.5%和74.3%。
Fe3O4nanoparticles were prepared by a chemical reduction method and then,along with polyferric chloride（ PFC）,used to produce a composite coagulant,MFPAC. Experiments investigating the pretreatment of landfill leachate were conducted using the combined coagulation process and aged-refuse adsorption process. The optimum working conditions of the combined process were determined by a single factor method. The results indicated that MFPAC offered a higher coagulation efficiency than PAC,with COD and color removals of 62. 6% and66. 5%,respectively. The optimum working conditions for the coagulation process were as follows： Fe3O4/ PAC mass ratio of 1 ∶ 3,MFPAC dosage of 1. 5 g·L^（-1）,stirring speed of 300 r·min- 1,stirring time of 60 s,coagulation time of 30 min,and pH of 7. 5. Under these conditions,the COD decreased from 5 810 to 2 173 mg·L^（-1）,and the color declined from 1 658 to 556 times. The effluent of the coagulation process was further treated by an aged-refuse adsorption process. The optimum working conditions of the adsorption process were as follows：aged refuse particle size of less than 2 mm,700 ℃ roasting temperature,40 mg·L^（-1）adsorbent,and pH 9. In the adsorption process,the COD and ammonia nitrogen removals reached 56. 7% and 68. 4%,respectively,after treatment for 12 h. The COD and ammonia concentrations decreased to 941 mg·L^（-1）and 343 mg·L^（-1）in the final effluent. By combining MFPAC coagulation with aged refuse adsorption,the COD,color,and ammonia nitrogen reduction could be increased to 83. 8%,78. 5%,and 74. 3%,respectively.
出处
《环境工程学报》
CAS
CSCD
北大核心
2017年第1期393-400,共8页
Chinese Journal of Environmental Engineering
