本文主要研究内容
作者扶海鹰（2019）在《红壤中铀的迁移转化规律及控制方法研究》一文中研究指出：南方的江西省、湖南省以及广东省曾经是我国铀生产的主要地区,这些地区分布着很多铀尾矿库。随着时间的推移,在各种物理化学和生物过程作用下,铀尾矿库中的铀会向周边的土壤环境迁移扩散,污染周边的农田土壤和地下水。而我国江西省、湖南省以及粤北地区主要的土壤类型为红壤。因此,研究铀在红壤中的迁移转化及其控制方法,有利于了解铀的环境化学行为,为预测铀在红壤中的迁移趋势,以及为铀污染红壤的修复提供理论基础。对于控制铀尾矿库周边地区红壤及地下水铀污染具有重要的意义。本文选择我国南方某铀尾矿库周边红壤作为研究对象,采用批次吸附实验、土柱迁移实验、氧化还原转化实验以及钝化修复实验,结合模型模拟与各种分析检测手段,探讨铀在红壤中的迁移转化过程和机理,并对铀污染红壤中铀的迁移活性控制方法进行了研究。论文的主要内容和结论如下:1.采集我国南方某铀尾矿库周边包气带红壤样品,分析其理化特性参数,表明该红壤属于壤质粘土,具有低有机质、低pH值的特点。通过批次吸附实验,研究硫酸根作为背景电解质,不同溶液初始pH值和碳酸根浓度条件下红壤对铀的吸附模型和机理,结果表明:(1)不同初始pH值以及不同碳酸根浓度条件下,红壤对铀的吸附动力学均符合准二级动力学模型,而等温吸附均符合Freundlich等温吸附模型。(2)铀主要通过与红壤表面的羟基(-OH)作用而被吸附。溶液中没有碳酸根时,溶液平衡时的pH值控制着红壤对铀的吸附能力。而溶液中存在碳酸根时,碳酸根浓度和初始pH值共同控制着红壤对铀的吸附。2.通过室内土柱迁移实验并结合HYDRUS-1D软件,模拟硫酸根为背景电解质时,不同初始pH值以及不同碳酸根浓度的含铀污水灌溉条件,研究铀在红壤土柱中的迁移规律和模型,结果表明:(1)溶液初始pH值越小,铀在红壤中的迁移活性越大;碳酸根浓度越大,铀在红壤中的迁移活性也越大。(2)两点化学非平衡模型能很好地模拟不同初始pH值以及不同碳酸根浓度时铀在红壤土柱中的迁移规律。且平衡吸附位点比例分数f的值与初始溶液中带正电荷的铀形态的含量值近似相等,在不同碳酸根浓度实验组中,f为0,可用一点化学非平衡模型模拟不同碳酸根浓度时的穿透曲线。(3)模型参数敏感性分析表明,分配系数_dk′是最关键的参数。两点化学非平衡模型4个模型参数的敏感性由大到小依次为:分配系数_dk′、一级吸附速率常数ω、平衡吸附位点比例分数f、纵向弥散系数λ;一点化学非平衡模型3个模型参数的敏感性由大到小为:分配系数_dk′、一级吸附速率常数ω、纵向弥散系数λ。3.采集红壤型稻田土壤进行室内氧化-还原振荡实验和还原实验,模拟稻田土壤的氧化还原动态环境,研究土壤中铀的价态和形态转化规律和机理,可得以下结论:(1)在还原实验中,土壤中稳定四价铀(晶质铀矿和U(IV)-磷酸盐)的含量存在饱和值,表明不稳定的单体四价铀短时间之内不能向稳定的四价铀转化。(2)氧化-还原振荡实验中,土壤中水溶性的铀含量轻微升高,这可能会增加铀的环境风险,但稳定四价铀的含量显著增加。且土壤中稳定的四价铀在氧化周期内不会被氧化。(3)土壤中微生物群落的改变以及土壤表面铁氧化物的氧化还原转化在铀的氧化还原转化过程中起到了关键的作用。(4)通过Tessier连续提取可知,氧化-还原振荡实验中,土壤中稳定四价铀的增加表现为醋酸盐提取态的铀向更稳定的羟胺提取态转化。4.采用稻壳生物炭钝化修复铀污染红壤。通过研究稻壳生物炭对溶液中铀的吸附特征,以及稻壳生物炭修复铀污染红壤后,红壤中铀的化学稳定性和酸雨条件下的迁移活性,得到以下结论:(1)中性条件下,稻壳生物炭对溶液中的铀具有较强的吸附能力。(2)稻壳生物炭修复酸性铀污染红壤后,土壤的pH值得到一定程度的改善。(3)通过合成沉淀浸出法(SPLP)可知铀污染红壤中约26.53%的铀可被提取,而添加5%和10%稻壳生物炭修复的铀污染红壤中铀的可提取率分别降至约2.58%和1.40%,表明稻壳生物炭修复后,红壤中铀的短期释放潜力大大降低。(4)Tessier连续提取可知,随着稻壳生物炭添加比例的增大,可交换态的铀含量减少,碳酸盐结合态的铀含量增多,铁锰氧化物结合态的铀略有减少,而有机质结合态和残渣态的铀含量基本不变。且可交换态与碳酸盐结合态铀的含量之和略有增多,可知稻壳生物炭修复后铀污染红壤中铀的化学稳定性仍然不高。(5)模拟三年酸雨量淋溶实验可知,铀污染红壤中约26.37%的铀被浸出,而添加5%和10%的稻壳生物炭修复的铀污染红壤相同条件下的浸出率分别只有7.30%和3.18%,表明稻壳生物炭修复后,红壤中铀的长期释放潜力也大大降低。
Abstract
na fang de jiang xi sheng 、hu na sheng yi ji an dong sheng ceng jing shi wo guo you sheng chan de zhu yao de ou ,zhe xie de ou fen bu zhao hen duo you wei kuang ku 。sui zhao shi jian de tui yi ,zai ge chong wu li hua xue he sheng wu guo cheng zuo yong xia ,you wei kuang ku zhong de you hui xiang zhou bian de tu rang huan jing qian yi kuo san ,wu ran zhou bian de nong tian tu rang he de xia shui 。er wo guo jiang xi sheng 、hu na sheng yi ji yue bei de ou zhu yao de tu rang lei xing wei gong rang 。yin ci ,yan jiu you zai gong rang zhong de qian yi zhuai hua ji ji kong zhi fang fa ,you li yu le jie you de huan jing hua xue hang wei ,wei yu ce you zai gong rang zhong de qian yi qu shi ,yi ji wei you wu ran gong rang de xiu fu di gong li lun ji chu 。dui yu kong zhi you wei kuang ku zhou bian de ou gong rang ji de xia shui you wu ran ju you chong yao de yi yi 。ben wen shua ze wo guo na fang mou you wei kuang ku zhou bian gong rang zuo wei yan jiu dui xiang ,cai yong pi ci xi fu shi yan 、tu zhu qian yi shi yan 、yang hua hai yuan zhuai hua shi yan yi ji dun hua xiu fu shi yan ,jie ge mo xing mo ni yu ge chong fen xi jian ce shou duan ,tan tao you zai gong rang zhong de qian yi zhuai hua guo cheng he ji li ,bing dui you wu ran gong rang zhong you de qian yi huo xing kong zhi fang fa jin hang le yan jiu 。lun wen de zhu yao nei rong he jie lun ru xia :1.cai ji wo guo na fang mou you wei kuang ku zhou bian bao qi dai gong rang yang pin ,fen xi ji li hua te xing can shu ,biao ming gai gong rang shu yu rang zhi nian tu ,ju you di you ji zhi 、di pHzhi de te dian 。tong guo pi ci xi fu shi yan ,yan jiu liu suan gen zuo wei bei jing dian jie zhi ,bu tong rong ye chu shi pHzhi he tan suan gen nong du tiao jian xia gong rang dui you de xi fu mo xing he ji li ,jie guo biao ming :(1)bu tong chu shi pHzhi yi ji bu tong tan suan gen nong du tiao jian xia ,gong rang dui you de xi fu dong li xue jun fu ge zhun er ji dong li xue mo xing ,er deng wen xi fu jun fu ge Freundlichdeng wen xi fu mo xing 。(2)you zhu yao tong guo yu gong rang biao mian de qiang ji (-OH)zuo yong er bei xi fu 。rong ye zhong mei you tan suan gen shi ,rong ye ping heng shi de pHzhi kong zhi zhao gong rang dui you de xi fu neng li 。er rong ye zhong cun zai tan suan gen shi ,tan suan gen nong du he chu shi pHzhi gong tong kong zhi zhao gong rang dui you de xi fu 。2.tong guo shi nei tu zhu qian yi shi yan bing jie ge HYDRUS-1Druan jian ,mo ni liu suan gen wei bei jing dian jie zhi shi ,bu tong chu shi pHzhi yi ji bu tong tan suan gen nong du de han you wu shui guan gai tiao jian ,yan jiu you zai gong rang tu zhu zhong de qian yi gui lv he mo xing ,jie guo biao ming :(1)rong ye chu shi pHzhi yue xiao ,you zai gong rang zhong de qian yi huo xing yue da ;tan suan gen nong du yue da ,you zai gong rang zhong de qian yi huo xing ye yue da 。(2)liang dian hua xue fei ping heng mo xing neng hen hao de mo ni bu tong chu shi pHzhi yi ji bu tong tan suan gen nong du shi you zai gong rang tu zhu zhong de qian yi gui lv 。ju ping heng xi fu wei dian bi li fen shu fde zhi yu chu shi rong ye zhong dai zheng dian he de you xing tai de han liang zhi jin shi xiang deng ,zai bu tong tan suan gen nong du shi yan zu zhong ,fwei 0,ke yong yi dian hua xue fei ping heng mo xing mo ni bu tong tan suan gen nong du shi de chuan tou qu xian 。(3)mo xing can shu min gan xing fen xi biao ming ,fen pei ji shu _dk′shi zui guan jian de can shu 。liang dian hua xue fei ping heng mo xing 4ge mo xing can shu de min gan xing you da dao xiao yi ci wei :fen pei ji shu _dk′、yi ji xi fu su lv chang shu ω、ping heng xi fu wei dian bi li fen shu f、zong xiang mi san ji shu λ;yi dian hua xue fei ping heng mo xing 3ge mo xing can shu de min gan xing you da dao xiao wei :fen pei ji shu _dk′、yi ji xi fu su lv chang shu ω、zong xiang mi san ji shu λ。3.cai ji gong rang xing dao tian tu rang jin hang shi nei yang hua -hai yuan zhen dang shi yan he hai yuan shi yan ,mo ni dao tian tu rang de yang hua hai yuan dong tai huan jing ,yan jiu tu rang zhong you de jia tai he xing tai zhuai hua gui lv he ji li ,ke de yi xia jie lun :(1)zai hai yuan shi yan zhong ,tu rang zhong wen ding si jia you (jing zhi you kuang he U(IV)-lin suan yan )de han liang cun zai bao he zhi ,biao ming bu wen ding de chan ti si jia you duan shi jian zhi nei bu neng xiang wen ding de si jia you zhuai hua 。(2)yang hua -hai yuan zhen dang shi yan zhong ,tu rang zhong shui rong xing de you han liang qing wei sheng gao ,zhe ke neng hui zeng jia you de huan jing feng xian ,dan wen ding si jia you de han liang xian zhe zeng jia 。ju tu rang zhong wen ding de si jia you zai yang hua zhou ji nei bu hui bei yang hua 。(3)tu rang zhong wei sheng wu qun la de gai bian yi ji tu rang biao mian tie yang hua wu de yang hua hai yuan zhuai hua zai you de yang hua hai yuan zhuai hua guo cheng zhong qi dao le guan jian de zuo yong 。(4)tong guo Tessierlian xu di qu ke zhi ,yang hua -hai yuan zhen dang shi yan zhong ,tu rang zhong wen ding si jia you de zeng jia biao xian wei cu suan yan di qu tai de you xiang geng wen ding de qiang an di qu tai zhuai hua 。4.cai yong dao ke sheng wu tan dun hua xiu fu you wu ran gong rang 。tong guo yan jiu dao ke sheng wu tan dui rong ye zhong you de xi fu te zheng ,yi ji dao ke sheng wu tan xiu fu you wu ran gong rang hou ,gong rang zhong you de hua xue wen ding xing he suan yu tiao jian xia de qian yi huo xing ,de dao yi xia jie lun :(1)zhong xing tiao jian xia ,dao ke sheng wu tan dui rong ye zhong de you ju you jiao jiang de xi fu neng li 。(2)dao ke sheng wu tan xiu fu suan xing you wu ran gong rang hou ,tu rang de pHzhi de dao yi ding cheng du de gai shan 。(3)tong guo ge cheng chen dian jin chu fa (SPLP)ke zhi you wu ran gong rang zhong yao 26.53%de you ke bei di qu ,er tian jia 5%he 10%dao ke sheng wu tan xiu fu de you wu ran gong rang zhong you de ke di qu lv fen bie jiang zhi yao 2.58%he 1.40%,biao ming dao ke sheng wu tan xiu fu hou ,gong rang zhong you de duan ji shi fang qian li da da jiang di 。(4)Tessierlian xu di qu ke zhi ,sui zhao dao ke sheng wu tan tian jia bi li de zeng da ,ke jiao huan tai de you han liang jian shao ,tan suan yan jie ge tai de you han liang zeng duo ,tie meng yang hua wu jie ge tai de you lve you jian shao ,er you ji zhi jie ge tai he can zha tai de you han liang ji ben bu bian 。ju ke jiao huan tai yu tan suan yan jie ge tai you de han liang zhi he lve you zeng duo ,ke zhi dao ke sheng wu tan xiu fu hou you wu ran gong rang zhong you de hua xue wen ding xing reng ran bu gao 。(5)mo ni san nian suan yu liang lin rong shi yan ke zhi ,you wu ran gong rang zhong yao 26.37%de you bei jin chu ,er tian jia 5%he 10%de dao ke sheng wu tan xiu fu de you wu ran gong rang xiang tong tiao jian xia de jin chu lv fen bie zhi you 7.30%he 3.18%,biao ming dao ke sheng wu tan xiu fu hou ,gong rang zhong you de chang ji shi fang qian li ye da da jiang di 。
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论文详细介绍
论文作者分别是来自南华大学的扶海鹰，发表于刊物南华大学2019-10-28论文，是一篇关于红壤论文,迁移模型论文,氧化还原循环论文,形态转化论文,生物炭论文,南华大学2019-10-28论文的文章。本文可供学术参考使用，各位学者可以免费参考阅读下载，文章观点不代表本站观点，资料来自南华大学2019-10-28论文网站，若本站收录的文献无意侵犯了您的著作版权，请联系我们删除。