乳化油原位去除地下水六价铬模拟实验研究

发布时间：2018-03-16 02:08

本文选题：地下水　切入点：六价铬　出处：《中国地质大学(北京)》2015年硕士论文　论文类型：学位论文

【摘要】：利用乳化油作为碳源用于地下水多种类型污染物的原位生物修复是近年来的研究热点。本论文以Cr(VI)污染的地下水为研究对象,以乳化油为电子供体,通过室内柱实验模拟原位去除地下水Cr(VI),考察了Cr(VI)去除效果以及乳化油注入后对含水层介质渗透性的影响。为了进一步提高Cr(VI)去除效率,分别探讨了硝酸盐的投加量、六价铬初始浓度以及乳化油的投加量对反应体系中Cr(VI)去除的影响。本次研究获得的主要结论如下:(1)乳化油去除Cr(VI)模拟柱实验结果表明,两次注入乳化油中,第一次注入乳化油反应周期比第二次长,与铬盐对微生物有毒害作用、乳化油降解速率慢有关。注入乳化油后,砂柱渗透系数降低量为58.44%~73.68%,随着出水体积的增加,含水层介质渗透性有所恢复,恢复到初始渗透系数的20%~50%。(2)模拟柱实验总共运行64天,两次注入乳化油共80 m L。进水Cr(VI)浓度为15 mg/L,出水口Cr6+浓度最低为2.46 mg/L。两次注入乳化油中Cr(VI)的去除量分别为32.60 mg、91.26 mg,去除率分别达到29.20%、72.13%,整个实验过程中Cr(VI)去除率为52.01%。乳化油利用效率评估结果表明,处理1 m3污染物含Cr(VI)化合物的浓度为15 mg/L的地下水,所消耗的乳化油的体积为9.69 L。(3)在以乳化油为碳源去除Cr(VI)静态实验中,硝酸盐的投加对Cr(VI)去除起到重要作用,当硝酸盐浓度为10 mg/L、乳化油投加量为2 m L时,Cr(VI)衰减速率常数K值为0.304d-1,去除率为100%,单位体积乳化油去除Cr(VI)的量为5.0 g/L。模拟柱实验中,单位体积乳化油去除Cr(VI)的量比组1、组2低,与未添加氮源、乳化油迁移流失有关。Cr(VI)初始浓度对乳化油微生物法去除Cr(VI)有重大影响,浓度过高(15 mg/L)会抑制微生物活性,进而影响Cr(VI)去除效果。
[Abstract]:In recent years, the use of emulsified oil as carbon source for in situ bioremediation of various types of pollutants in groundwater has been a hot topic. In this paper, CrVI contaminated groundwater is taken as research object, emulsified oil as electronic donor, and emulsified oil as electron donor. In order to further improve the removal efficiency of CrVI, the removal effect of CrVI and the effect of emulsified oil injection on the permeability of aquifer media were investigated by simulating the in-situ removal of groundwater in situ by column experiments, and the amount of nitrate added was discussed respectively. The effect of the initial concentration of hexavalent chromium and the amount of emulsified oil on the removal of CrVI in the reaction system. The main conclusions obtained in this study are as follows: 1) removal of CrVI from emulsified oil by emulsified oil. The reaction period of the first injection of emulsified oil is longer than that of the second one, which is related to the toxic effect of chromium salt on microorganism and the slow degradation rate of emulsified oil. After injected with emulsified oil, the permeability coefficient of sand column decreases to 58.44 and 73.68, and with the increase of effluent volume, The permeability of the aquifer media has been restored to 20 / 50 / 2 of the initial permeability coefficient.) the experiment on the simulated column runs for a total of 64 days. The twice injected emulsified oil contains 80 mL. The influent CrVI concentration is 15 mg / L, the lowest Cr6 concentration at the outlet is 2.46 mg / L. the removal rate of CrVI in the emulsified oil is 32.60 mg / L 91.26 mg / L, respectively, and the removal rate is 29.20 mg / L, respectively. During the whole experiment, the CrVI removal rate is 52.01% and 52.01 mg / L, respectively. The evaluation results of emulsified oil utilization efficiency show that, The volume of emulsified oil consumed in groundwater with the concentration of 15 mg/L for treatment of 1 m3 pollutant containing CrVI was 9.69 L 路m3) in the static experiment of removing CrVI with emulsified oil as carbon source, the addition of nitrate played an important role in the removal of CrVI. When nitrate concentration is 10 mg / L and emulsified oil dosage is 2 mL, the decay rate constant K value is 0.304 d ~ (-1), the removal rate is 100 g / L, and the removal rate of CrVI is 5.0 g 路L ~ (-1) by unit volume emulsified oil. In the simulated column experiment, the removal rate of CrVI by emulsified oil per unit volume is lower than that of group 1 and group 2, respectively. In the absence of nitrogen source, the initial concentration of .Cr-VI has a significant effect on the removal of Cr-VI by microbiological method of emulsified oil, and the concentration of 15 mg / L can inhibit the microbial activity and then affect the removal efficiency of Cr-VI.
【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X523

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