流化床石英砂结晶法处理含氟废水
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摘要
含氟废水常用化学沉淀法处理,但会产生大量含水率高的污泥,增加处理成本,且难以回收利用氟。本实验提出流化床石英砂结晶法新工艺,通过CaF_2晶体沉淀形态、过饱和度和循环条件对除氟效果影响的研究,建立了流化床中CaF_2沉淀的控制机理。机理表明:CaF_2过饱和度不超过临界值,流化床出水不循环,可增加附着沉淀,减少离散沉淀,提高流化床除氟效率。流化床出水经PAC絮凝沉淀后,可达国家污水综合排放一级。流化床产生的CaF_2沉渣含水率低,可回收利用。石英砂能反复再生利用。
The common techniques for fluoride wastewater treatment is chemical precipitation,but it may produce a large amount of sludge with high moisture content and may increase the treatment costs and make fluorine recycling difficult. A novel quartz sand crystallization in fluidized bed(FB) is then proposed to remove fluoride from wastewater. The control mechanism of CaF_2 precipitation is established by studying on the effect of precipitation form,supersaturation and cyclic conditions on F-removal efficiency. The mechanism shows that CaF_2 supersaturation doesn't exceed the critical value and without circulating treated water,which may increase attached precipitation,reduce discrete precipitation and improve the F-removal efficiency of FB. The fluoride concentration of effluent can meet the primary requirements of Integrated Wastewater Discharge Standard after PAC flocculation precipitation. The CaF_2 sediment of low moisture content and quartz sand can be recycled.
The common techniques for fluoride wastewater treatment is chemical precipitation,but it may produce a large amount of sludge with high moisture content and may increase the treatment costs and make fluorine recycling difficult. A novel quartz sand crystallization in fluidized bed(FB) is then proposed to remove fluoride from wastewater. The control mechanism of CaF_2 precipitation is established by studying on the effect of precipitation form,supersaturation and cyclic conditions on F-removal efficiency. The mechanism shows that CaF_2 supersaturation doesn't exceed the critical value and without circulating treated water,which may increase attached precipitation,reduce discrete precipitation and improve the F-removal efficiency of FB. The fluoride concentration of effluent can meet the primary requirements of Integrated Wastewater Discharge Standard after PAC flocculation precipitation. The CaF_2 sediment of low moisture content and quartz sand can be recycled.
引文
[1]李雪玲,刘俊峰,李培元.石灰沉淀法除氟的应用[J].水处理技术,2000,26(6):359-361.
[2]吴倩,李晓凯,申亮.高氟地下水处理技术现状[J].辽宁化工,2011,40(4):355-359.
[3]卢宁,高乃云,徐斌,等.饮用水除氟技术研究的新进展[J].四川环境,2007,26(4):119-122.
[4]Mohapatra M,Anand S.Review of fluoride removal from drinking water[J].Journal of Environmental Management,2009,91(1):67-77.
[5]李程文,周康根,姜科,等.晶种法处理含氟废水与氟化钙沉淀砂状化研究[J].环境科学与技术,2011,34(5):157-160.
[6]黄廷林,孙田,邓林煜.诱导结晶法去除地下水中氟离子[J].环境工程学报,2014,8(1):1-5.
[2]吴倩,李晓凯,申亮.高氟地下水处理技术现状[J].辽宁化工,2011,40(4):355-359.
[3]卢宁,高乃云,徐斌,等.饮用水除氟技术研究的新进展[J].四川环境,2007,26(4):119-122.
[4]Mohapatra M,Anand S.Review of fluoride removal from drinking water[J].Journal of Environmental Management,2009,91(1):67-77.
[5]李程文,周康根,姜科,等.晶种法处理含氟废水与氟化钙沉淀砂状化研究[J].环境科学与技术,2011,34(5):157-160.
[6]黄廷林,孙田,邓林煜.诱导结晶法去除地下水中氟离子[J].环境工程学报,2014,8(1):1-5.