水体黑臭演化过程及挥发性硫化物的产生机制初步研究
文献类型:学位论文
作者 | 孙韶玲![]() |
学位类别 | 硕士 |
答辩日期 | 2017-05-17 |
授予单位 | 中国科学院大学 |
授予地点 | 北京 |
导师 | 盛彦清 |
关键词 | 黑臭水体 水质 挥发性硫化物 河道 |
中文摘要 | 随着城镇化以及工业化进程的加快,生活污水的过度排放造成了河道富营养化,甚至导致水体呈现黑臭状态。水体黑臭是河道水环境污染极其严重的表现,认识水体黑臭演化过程对开展水污染防治至关重要。国内外关于水体黑臭的研究主要集中在黑臭水形成机理、水体黑臭的评价方法等方面,对于黑臭水体形成条件以及水体中恶臭挥发性硫化物形成过程的研究明显不足。 本研究在实验室模拟条件下,结合滨海河流水质特点,重点研究了总有机碳(TOC)、总氮(TN)、Fe2+浓度及水体盐度等水质因子对水体黑臭演化过程的影响,同时分析了不同水质条件下甲硫醇(MT)和H2S等挥发性硫化物的产生机制。通过采用河流原水进行接种制备人工黑臭水,设定不同的TOC,TN、Fe2+浓度和水体盐度梯度进行模拟实验,分析了单一水质因素对水体黑臭形成的影响;为了进一步认识各种水质因素之间的相互作用及其对黑臭水体形成的综合影响,本文同时开展了多因素正交试验。 主要有以下结论: (1)微生物作用在水体黑臭过程中发挥关键作用。研究发现河流水体黑臭状态的形成与水体中的微生物量具有显著相关性,当水体中的厌氧微生物数量增多时,水体黑臭时间变短,黑臭现象更明显,表明水体在厌氧的状态更易形成黑臭现象。 (2)碳源是黑臭形成的重要条件。TOC浓度小于50 mg/L时,水体不会变黑,产生的挥发性硫化物总量较少,有臭味产生但不强烈;TOC浓度大于100 mg/L时,TOC浓度越高,水体黑臭的时间越短,黑臭程度越明显,产生的MT和H2S量越多,实验结束时,色度均大于500 度,MT和H2S总量都超过了1 g/L。 (3)氮源也是黑臭形成的重要因素。TN浓度为0时,水体不变黑臭; C/N小于2:1,此时总氮浓度过高,水体致黑臭的过程较慢,C/N在3:1至4:1的范围内较容易形成黑臭现象;TN浓度在一定范围内,随着浓度增大,水体发生黑臭时间变短,并且黑臭程度越来越明显。 (4)Fe2+浓度不仅与色度有关,也是臭味产生的重要条件。研究发现Fe2+浓度大于10 mg/L的水体会出现明显的黑色浑浊现象,而Fe2+浓度小于5 mg/L时水体仅会变浑浊。这表明Fe2+浓度越高的水体变黑的程度越显著。此外,Fe2+浓度越高的水体中MT和H2S浓度越高,这可能是由于 Fe2+能促进硫酸盐还原菌的代谢过程,进而促进了恶臭硫化物的产生。因此,Fe2+浓度对黑臭水体的形成有显著影响。 (5)高盐度水体,抑制黑臭水形成。盐度过高,会抑制微生物的生长代谢过程,盐度达到15 ‰以上时,抑制作用显著。盐度在小于10 ‰的范围内,盐度较高时,对水体黑臭的形成有一定促进作用。盐度为10 ‰的水体实验结束时水体黑臭程度最显著,生成的主要挥发性硫化物MT和H2S的总量超过850 μg/L。 (6)正交试验的研究结果发现, TOC对水体黑臭的影响显著,TN和Fe2+浓度对水体黑臭的影响较明显,其中Fe2+浓度在水体变臭的过程中起到一定的促进作用。 |
英文摘要 | With the accelerating urbanization and industrialization, over discharge of domestic wastewater results in eutrophication, and even lead to smelly black water to form the black and odorous water. The black-odor water is a typical phenomenon of heavily polluted river. It is important to investigate the mechanism of water quality evolution for water pollution prevention and remediation. At present, the research about black-odor water mainly concentrates on the formation mechanism and the evaluation method of black and odorous water body. However, the study on the formation conditions of black-odor water and the formation of volatile sulfide in the odorous substances in water are obviously insufficient. In the present dissertation, combined the water quality characteristics of estuaries and coastal zones with the simulation experiment in the laboratory, influences of four important water quality factors such as total organic carbon (TOC), total nitrogen (TN), Fe2+ and salinity, on the formation of black-odor in water body are systematically studied. At the same time, the generation mechanisms of volatile odorous sulfides including methyl mercaptan (MT) and H2S were analyzed under different water quality conditions. Through setting the different concentration gradients of TOC, TN, Fe2+ and salinity during artificial preparation of black-odor water, inoculated mixed bacteria from river water the effects of varied factors on the formation of black odor water are sutdied repectively. Another objective of this study is to designed a multi-factor orthogonal test for further understanding the comprehensive influence of various water quality factors on the formation of black-odor water. The main conclusions are as follows: (1) Microbial action played a key role in the process of black-odor water. The result show that the microbial biomass have a obviously impact on the formation of black-odor water. With the increase of anaerobic microorganisms in the water body, the formation time of the black-odor water is reduced and the black and odorous phenomenon is more obvious, indicating that under the anaerobic condition, the black and odorous phenomenon is easily formed in water. (2) Carbon source is a important condition for the formation of black and odorous water. When the concentration of TOC is less than 50 mg / L, the water will not turn black, just produce a small amount of odor, and the total amount of H2S and MT will reach 21.83 μg / L. When the concentration of TOC is more than 100 mg / L, the total amount of the MT and H2S are more than 1 g/L. At the end of the experiment, the chromaticity is over 500 degrees. (3) Nitrogen source is also a important condition for the formation of black smelly. When the concentration of TN is 0, the water body is not black and smelly. When ratio of C/N is less than 2:1, the formation of black and odorous water is slow. when C/N is ranged from 3:1 to 4:1, with the increase of the TN concentration during a certain range of TN concentration, the the formation time of black and odorous water decrease and the black -odor degree of warer is more obvious. (4) Fe2+ concentration is not only related to chroma, but also an important condition for the generation of odor. Our result show that, when Fe2+ concentration is over 10 mg/L result in blackened and turbid phenomenon in water, when Fe2+ concentration is less than 5 mg/L just lead to turbid phenomenon in water, indicating that the blackened degree is significantly raised with the increase of Fe2+ concentration. Besides, as the increase of Fe2+ concentration, the concentrations of MT and H2S are dramatically raised in water,which is attributed to promote the metabolism process of sulfate reducing bacteria, and then increase the concentrations of odorous sulfide. Thus, Fe2+ concentration has a obviously impact on the formation of black-odor water. (5) High salinity can inhibit the formation of black water.High salinity can inhibit the growth and metabolism of microbial processes. When salinity is more than 15 ‰, the inhibition was significant. In the less than 10 ‰ salinity range, salinity plays an important role in promoting the formation of black and odorous water. At the end of the experiment, the black and odorous degree in the water at salinity of 10 ‰ is the most significant, and the concentrations of MT and H2S exceeds 850 μg/L. (6) The results of orthogonal test show that TOC has a significant effect on the black and odorous water and the effects of TN and Fe2+ on black and odorous water is obvious. Fe2+ concentration plays an important role in promoting the formation of odorous water. |
学科主题 | 环境科学技术 |
源URL | [http://ir.yic.ac.cn/handle/133337/22002] ![]() |
专题 | 中科院烟台海岸带研究所知识产出_学位论文 |
作者单位 | 中科院烟台海岸带研究所 |
推荐引用方式 GB/T 7714 | 孙韶玲. 水体黑臭演化过程及挥发性硫化物的产生机制初步研究[D]. 北京. 中国科学院大学. 2017. |
入库方式: OAI收割
来源:烟台海岸带研究所
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