摘要
以纳米TiO_(2)(Nano-TiO_(2))为光催剂、Fe_(3)O_(4)/SiO_(2)(FS)为磁性絮凝剂,提出了一种通过调节pH值来实现Nano-TiO_(2)磁絮凝回收及解絮凝释放的回收再利用系统;研究了FS/Nano-TiO_(2)质量比和相同质量比下Nano-TiO_(2)浓度对系统絮凝性能的影响,考察了造纸废水预处理方式对Nano-TiO_(2)光催化-磁絮凝回收循环光降解性能的影响。结果表明,FS/Nano-TiO_(2)质量比越大或相同质量比下NanoTiO_(2)浓度越高,两者形成的FS/Nano-TiO_(2)絮凝体的沉降速率越快,越有利于Nano-TiO_(2)的磁絮凝回收;经浓度为0.6 g/L Nano-TiO_(2)絮凝处理后的造纸废水(SBR-T)在光催化降解180 min后,其COD_(Cr)、固体悬浮物、浊度及色度分别下降了89.2%、98.2%、99.3%和99.3%,基本实现造纸废水的深度处理;相较于离心处理的造纸废水(SBR-C)的光催化降解性能(下降了25.2%),SBR-T的光催化降解性能仅下降了11.4%,表明预先去除废水中的固体悬浮物可减少回收再利用过程中Nano-TiO_(2)的流失,使系统保持较高的降解效率。
With Nano-TiO_(2)(Nano-TiO_(2))as the photo catalyst and Fe_(3)O_(4)/SiO_(2)(FS)as the magnetic flocculant,a recovery and reuse system for Nano-TiO_(2) magnetic flocculation recovery and deflocculation release was proposed by adjusting the pH value.The effects of mass ratio of FS and Nano-TiO_(2) and Nano-TiO_(2) concentration under same mass ratio on the flocculation performance of the system were studied,and the effect of papermaking wastewater pretreatment on the degradation performance of the cyclic photocatalytic system was investigated.The results show that the higher the mass ratio of FS and Nano-TiO_(2) or the greater the concentration of Nano-TiO_(2) under the same ratio,the faster the sedimentation rate of the flocs formed by the two materials,the more conducive to the magnetic recovery of Nano-TiO_(2).After treated by flocculation with 0.6 g/L Nano-TiO_(2) and photocatalytic degradation for 180 min,the COD_(Cr),suspended solids,turbidity,and chroma of papermaking wastewater(SBR-T)decreased by 89.2%,98.2%,99.3%and 99.3%,respectively,basically realizing advanced treatment of papermaking wastewater.Compared with the centrifugally treated papermaking wastewater(SBR-C)with a decrease in photocatalytic degradation performance by 25.2%,the photocatalytic degradation performance of SBR-T decreased by merely 11.4%;indicating that the pre-removal of suspended solids in wastewater can reduce the loss of Nano-TiO_(2) in the recycling process so that the system maintains high degradation efficiency.
作者
林英行
陈小泉
LIN Yinghang;CHEN Xiaoquan(State Key Laboratory of Pulp and Paper Engineering,South China University of Technology,Guangzhou,Guangdong Province,510640)
出处
《中国造纸学报》
CAS
CSCD
北大核心
2022年第3期109-117,共9页
Transactions of China Pulp and Paper
基金
国家自然科学基金项目(21466000)
纳米TiO_(2)胶体对造纸有机污染物光催化降解机理研究(Y1090010)。
