【作者】 韩惟怡；

【导师】 龚文琪；

【作者基本信息】 武汉理工大学 ， 环境工程， 2012， 硕士

【摘要】 随着矿产品市场的繁荣和产品价格的飙升,为了进一步提高矿产品的选矿回收率,选矿工艺正在被不断延长,选矿药剂被大量使用甚至是滥用,这在为企业带来经济效益的同时,也给环境造成了巨大危害。羟肟酸作为一类新型的螯合浮选捕收剂,在选矿工艺中被广泛使用。目前,对羟肟酸的生物处理研究较少,特别是对含羟肟酸类捕收剂的选矿工业废水的研究几乎为空白。因此,研究羟肟酸类捕收剂与含羟肟酸捕收剂的浮选试验废水在好氧与厌氧条件下的生物降解性,探索其生物降解规律与机理,不仅能为生物处理含羟肟酸捕收剂的选矿工业废水提供一定的理论指导,也能填补国内在这一研究领域的空白,有着非常现实的意义。对不同初始浓度的羟肟酸类捕收剂的生物降解性的研究表明：苯甲羟肟酸的生物降解度随时间的变大呈直线上升,其生物降解符合零级动力学模型；水杨羟肟酸、N-羟基邻苯二甲酰亚胺和H205的生物降解在降解初期较快而后变化趋于平缓,初始浓度越高微生物的降解作用越小,其降解过程符合一级动力学模型。不同结构的羟肟酸类捕收剂生物降解性能差别很大。苯甲羟肟酸、水杨羟肟酸和N-羟基邻苯二甲酰亚胺属于易生物降解捕收剂；H205属于难生物降解捕收剂,其生物降解性随着初始浓度的增大其可生物降解性急剧下降。对难降解的羟肟酸捕收剂H205在四种厌氧条件(一般厌氧条件、反硝化厌氧条件、硫酸盐厌氧条件及Fe(Ⅲ)还原厌氧条件)下的生物降解性的研究表明：H205在不同厌氧降解体系中的降解速率常数大小顺序为：kFe(Ⅲ)还原>k反硝化还原>k硫酸盐还原>k一般厌氧,Fe(Ⅲ)为H205厌氧生物降解最适宜的电子受体。H205在不同厌氧条件下的生物降解都符合一级动力学模型,动力学方程分别为C=29.86e-0.01477t,C=29.91e--·04276t,C=29.89e-0·02623t,C=29.95e-0·05597t。另外对比好氧生物降解与Fe(Ⅲ)还原厌氧的生物降解特性,表明好氧生物降解与Fe(Ⅲ)厌氧生物降解相结合的方式更加适合H205的生物降解。对含典型羟肟酸类捕收剂的浮选试验废水在好氧单基质、好氧共基质以及Fe(Ⅲ)厌氧条件下生物降解性的研究表明：对于含水杨羟肟酸的浮选试验废水,5%为最佳接种度,添加乙酸钠15mg-L-1、酵母浸膏30mg·L-1时生物降解度由54.25%提高到91.38%,且CODCr降到21.64mg·L-’,符合一级排放标准。对于含H205的浮选试验废水,8%为最佳接种度,添加甘露孵30mg·L-1、酵母浸膏60mg·L-1时生物降解度由20.21%提高到52.39%,且CODCr由125.56mg·L-1降到76.86mg·L-1。Fe(Ⅲ)厌氧降解效果不如好氧共代谢的降解效果。最后研究了羟肟胺的生物降解机理。羟肟酸在降解过程中,肟基先断裂生成芳香径羧酸和羟胺,弪胺在酶的作用下生成NH3和H2O；只有一个苯环的芳香羟羧酸生成邻苯二酚而后邻位羟基断裂生成粘糠酸,进而进入TCA循环生成CO2和H2O；含有萘环的芳香羟羧酸则先开环生成水杨酸,再进入TCA循环。更多还原

【Abstract】 With the prosperity of the minerals market and the soaring of minerals price, in order to further improve the recovery rate of minerals, mineral processing is being continuously extended; mineral processing reagents are widely used and even abused, which has brought economic benefit to the market but also caused tremendous harm to the environment. Hydroxamic acid, as a new type of chelating flotation collector, is widely used in the beneficiation process. But research on biological treatment of hydroxamic acid is less, at the same time almost no research on the actual flotation beneficiation wastewater containing hydroxamic acid. So the study of hydroxamic acid collector and the biodegradability of flotation test wastewater containing hydroxamic acid under aerobic and anaerobic conditions were conducted to clarify its law and mechanism of biological degradation to provide a theoretical basis for the biological treatment of real flotation beneficiation wastewater containing hydroxamic acid.The research on the biodegradation of hydroxamic acid collectors with different initial concentrations indicated that:the biodegradable of benzohydroxamic acid rose perpendicularly with time, which was followed the grade0dynamic model. The biodegradable salicyl hydroxamic acid, N-hydroxy phthalimide and H205rapidly changed in the early stage and then flattened. The higher the initial concentration, the more difficult of biodegradation carried on. The processes followed grade1dynamic model. Meanwhile, the biodegradation of the hydroxyl acid collectors with different structures differed greatly. Benzohydroxamic acid, salicyl hydroxamic acid and N-hydroxy phthalimide belonged to readily biodegradable collector. But the H205belonged to difficultly to be biodegradable collector, whose biodegradability sharply declined with the increasing of initial concentration.The research on the biodegradability of H205, which was a kind of difficultly-biodegradable hydroxyl acid collector, under four anaerobic conditions (general anaerobic, denitrifying anaerobic, sulfate anaerobicd and Fe(III) anaerobic) indicated that:the degradation rate of the H205in the different anaerobic degradation system followed the order of: kFe(III) anaerobic> ksulfate anaerobic> kdenitrifying anaerobic> kgencral anaerobic. Fe(III) was the the most appropriate electronic receptors to the anaerobic biodegradation of H205. All biodegradation processes of H205under different anaerobic conditions followed grade1dynamic model. The dynamic modeles were C=29.86e-0.01477t, C=29.91e-0.04276t,C=29.89e-0.02623t, C=29.95e-0.05597t. Moreover, contrasting the processes of aerobic biodegradation and Fe(III) anaerobic biodegradation of H205, the way to biodegradation combining aerobic biodegradation and Fe(III) reduction anaerobic biodegradation fit for the biodegradation of H205.The research on the biodegradation of the flotation test wastewater containing hydroxyl acid collector under aerobic single matrix condition, aerobic co-substrates condition and Fe(III) anaerobic condition showed that:5%was the best sludge concentration for the biodegradation of the pilot wastewater containing salicylic hydroxamic acid, and the the biodegradation increased from54.25%to91.38%when sodium acetate15mg·L-1and yeast extract30mg·L-1were put in. Meanwhile, the CODCr descended to21.64mg·L-1, conformanced to grade1of the national standard.8%was the best sludge concentration for the biodegradation of the pilot wastewater containing H205, and the the biodegradation increased for20.21%to52.39%when sodium acetate15mg·L-1and yeast extract30mg·L-1were put in. Meanwhile, the CODCr decreased from125.56mg·L-1to76.86mg·L-1. The effect of Fe(III) anaerobic biodegradation was not as good as anaerobic degradation of metabolism.At the end, the biodegradation pathways of hydroximic acid were analysized. In the degradation process of hydroximic acid, oximido is ruptured to form aryl hydroximic acid and hydroxylamine firstly. Then hydroxylamine is oxidized furthermore to form NH3and H2O. Aryl hydroximic acid with only one benzene ring is generated to o-benzenediol then via O-hydroxy-cutting, and muconic acid is produced. Finaly, CO2and H2O are produced by TCA. Aryl hydroximic acid with naphthalene is generated to salicylic acid via ring opening, and then enters the TCA.更多还原