氧气浓度和活化温度协同调控热氧活化污泥水热炭性质并强化四环素吸附的研究  

The synergistic effects of oxygen concentration and activation temperature on thermal oxidation activated sludge hydrochar for tetracycline adsorption

作　　者：黄华[1] 高海龙 南莎莎 刘小艳 单显莹 牛志睿[1] HUANG Hua;GAO Hailong;NAN Shasha;LIU Xiaoyan;SHAN Xianying;NIU Zhirui(Shaanxi Engineering and Technological Research Center for Conversation and Utilization of Regional Biological Resources,Yan’an Key Laboratory of Agricultural Solid Waste Resource Utilization,School of Petroleum and Environment Engineering,Yan’an University,Yan’an 716000;Shaanxi Yile Soil Improvement Technology Co.,Ltd.,Xi’an 712100;Shaanxi Hecongran Environmental Technology Co.,Ltd.,Xi’an 710061)

机构地区：[1]延安大学石油工程与环境工程学院,延安市农业固体废弃物资源化利用重点实验室,陕西省区域生物资源保育与利用工程技术研究中心,延安716000 [2]陕西宜乐土壤改良技术有限公司,西安712100 [3]陕西禾从然环保科技有限公司,西安710061

出　　处：《环境科学学报》2024年第4期61-69,共9页Acta Scientiae Circumstantiae

基　　金：陕西省重点研发计划项目(No.2022NY-058);陕西省自然科学基础研究计划(No.2021JQ-618);延安市科技计划项目(No.2022SLZDCY-011)。

摘　　要：利用高氧浓度气体取代空气可以有效降低热氧活化温度并显著提高生物炭对特定污染物的吸附量,但还缺乏氧气浓度和活化温度的协同效应研究.本研究探索了氧气浓度和活化温度对污泥水热炭吸附四环素的影响,采用元素分析、FTIR、XPS等方法对典型材料进行表征,确定了最优条件下热氧活化强化污泥水热炭强化吸附四环素的机理.结果表明:活化水热炭对四环素的吸附量随着活化温度的升高先升高后下降.当活化温度较低时,提高氧气浓度可以大幅提高活化炭的吸附量;当活化温度较高时,氧气浓度的影响不明显.氧气浓度为50%~100%、活化温度为225~237℃条件下可以稳定得到高四环素吸附量的活化炭.最优活化炭(100%氧气和230℃)对应最高四环素吸附量(C_(0)=100 mg·L^(-1),q_(e)=73.57 mg·g^(-1))和中等热蚀损失率(4.83%),其四环素吸附量较原始水热炭提高了2.17倍,较宽的活化条件有利于缓冲活化过程温度、氧气的波动,并有利于废气和废热的循环利用.材料表征结果显示,热氧活化可以提高材料的极性((O+N)/C)、羧基和羟基密度,进而提升静电吸引和π-πEDA等作用,强化了对四环素的吸附.本研究可为制备廉价、高效污泥炭吸附剂提供有益的参考.Using high oxygen concentration gas instead of air can decrease the optical activation temperature for thermal oxygen activation(TOA)and increase the adsorption capacity of activated biochar for specific pollutants.However,it is unclear what synergistic effects exist between oxygen concentration(C_(O2))and activation temperature(T_(a)).This study investigated the effects of C_(O2)and T_(a)on the tetracycline(TC)adsorption(q_(e))by activated sludge hydrochar(HC).Typical HCs were characterized by elemental analysis,FTIR,XPS,etc.The mechanism of TOA-enhanced TC adsorption under optimal activated condition was determined.The results showed that the q_(e)was initially decreased then increased with increasing T_a.When T_(a)was low,increasing C_(O2)effectively increased q_e.When T_(a)was high,the influence of C_(O2)on q_(e)was weak.The best activated HC resulted from230℃and 100%O_(2)had the highest q_(e)(73.57 mg·g^(-1))and a moderate burn off(4.83%).It increased q_(e)by 2.17 times compared to HC alone.It had a wide buffer range of 225~237℃and 50%~100%O_(2)which benefited recycling waste gas and heat efforts.TOA mainly enhanced the TC adsorption by increasing the polarity((O+N)/C),carboxyl and hydroxyl,as well as promoting electrostatic attraction,π-πEDA,etc.The results of this study will provide theoretical references for the preparation of inexpensive and efficient sludge-based adsorbents.

关 键 词：活性污泥 水热炭化 热活化 吸附剂 氧气浓度 抗生素 

分 类 号：X705[环境科学与工程—环境工程] X131