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对净化废气中SO2的生物膜填料塔内的微生物进行了分离纯化并做鉴定,得到一株嗜酸性氧化硫硫杆菌(Acidithiobacillus thiooxidans IEL001)和一株分类地位非常接近链二孢属(Bispora sp.)的极端嗜酸真菌IEL002,生物膜填料塔内的极端酸性环境和有机营养的缺乏导致生物膜上的微生物种类较为单一,多样性程度不高。本研究还发现IEL002自身并不能氧化单质硫,但它能促进Acidithiobacillus thiooxidans IEL001对单质硫的氧化。 相似文献
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以城市污水处理厂高含固污泥为对象,分别进行了连续厌氧消化抑硫试验和消化污泥Fe(Ⅲ)投加抑硫试验,探讨不同Fe/S(摩尔比)对污泥厌氧消化中溶解态硫化物去除效率的影响以及Fe(Ⅲ)与pH的交互作用.结果表明,热水解污泥厌氧消化采用原位抑硫技术,在Fe/S(摩尔比)为7.75时沼气中H_2S含量可由170.4×10~(-6)降至14.09×10~(-6),无需进行后续处理;当pH为7.00~7.50、Fe/S为1~11时,pH为原位抑硫主要显著影响因子,提高消化池pH有利于降低Fe(Ⅲ)投加量;高含固污泥厌氧消化沼气满足H_2S利用标准时,所需最低Fe/S为7.0;当消化池pH低于7.30时,将无法通过调节Fe/S实现H_2S浓度达标排放. 相似文献
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This work investigates the effects of lubricant sulfur contents on the morphology, nanostructure, size distribution and elemental composition of diesel exhaust particle on a light-duty diesel engine. Three kinds of lubricant (LS-oil, MS-oil and HS-oil, all of which have different sulfur contents: 0.182%, 0.583% and 1.06%, respectively) were used in this study. The morphologies and nanostructures of exhaust particles were analyzed using high-resolution transmission electron microscopy (TEM). Size distributions of primary particles were determined through advanced image-processing software. Elemental compositions of exhaust particles were obtained through X-ray energy dispersive spectroscopy (EDS). Results show that as lubricant sulfur contents increase, the macroscopic structure of diesel exhaust particles turn from chain-like to a more complex agglomerate. The inner cores of the core-shell structure belonging to these primary particles change little; the shell thickness decreases, and the spacing of carbon layer gradually descends, and amorphous materials that attached onto outer carbon layer of primary particles increase. Size distributions of primary particles present a unimodal and normal distribution, and higher sulfur contents lead to larger size primary particles. The sulfur content in lubricants directly affects the chemical composition in the particles. The content of C (carbon) decreases as sulfur increases in the lubricants, while the contents of O (oxygen), S (sulfur) and trace elements (including S, Si (silicon), Fe (ferrum), P (phosphorus), Ca (calcium), Zn (zinc), Mg (magnesium), Cl (chlorine) and Ni (nickel)) all increase in particles. 相似文献
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新型生物质活性炭烟气脱硫研究 总被引:2,自引:0,他引:2
以农业废弃物核桃壳为原料,天然软锰矿为添加剂共混制备得到的新型生物质柱状活性炭进行烟气脱硫的性能研究.采用固定床反应器进行脱硫实验,装填活性炭质量为16 g,考察了进口SO2含量、空速、床层温度、水蒸气和氧气含量等工艺参数对活性炭脱硫性能的影响.结果表明,进口SO2含量在0.1%~0.3%(体积含量)范围内时,活性炭的穿透硫容和穿透时间随着进口SO2含量的升高而降低;空速越大,活性炭越容易穿透,较佳的空速为600 h-1;最适的床层温度为80℃,过高会降低脱硫效率;水蒸气和氧气的存在大大促进了活性炭对SO2的吸附性能,最佳水蒸气含量为10%,最佳氧气含量为10%~13%.在最佳工艺操作条件下,当进口SO2含量为0.2%时,活性炭穿透硫容为252 mg.g-1,穿透时间可达26 h. 相似文献
38.
Sulfur speciation and bioaccumulation in camphor tree leaves as atmospheric sulfur indicator analyzed by synchrotron radiation XRF and XANES 总被引:2,自引:0,他引:2
Jianrong Zeng Guilin Zhang Liangman Bao Shilei Long Mingguang Tan Yan Li Chenyan M Yidong Zhao 《环境科学学报(英文版)》2013,25(3):605-612
Analyzing and understanding the effects of ambient pollution on plants is getting more and more attention as a topic of environmental biology.A method based on synchrotron radiation X-ray fluorescence and X-ray absorption near edge structure spectroscopy was established to analyze the sulfur concentration and speciation in mature camphor tree leaves (CTLs),which were sampled from 5 local fields in Shanghai,China.Annual SO2 concentration,SO42-concentration in atmospheric particulate,SO42-and sulfur concentration in soil were also analyzed to explore the relationship between ambient sulfur sources and the sulfur nutrient cycling in CTLs.Total sulfur concentration in mature camphor tree leaves was 766-1704 mg/kg.The mainly detected sulfur states and their corresponding compounds were +6 (sulfate,include inorganic sulfate and organic sulfate),+5.2 (sulfonate),+2.2 (suloxides),+0.6 (thiols and thiothers),+0.2 (organic sulfides).Total sulfur concentration was strongly correlated with sulfate proportion with a linear correlation coefficient up to 0.977,which suggested that sulfur accumulated in CTLs as sulfate form.Reduced sulfur compounds (organic sulfides,thiols,thioethers,sulfoxide and sulfonate) assimilation was sufficed to meet the nutrient requirement for growth at a balanced level around 526 mg/kg.The sulfate accumulation mainly caused by atmospheric sulfur pollution such as SO2 and airborne sulfate particulate instead of soil contamination.From urban to suburb place,sulfate in mature CTLs decreased as the atmospheric sulfur pollution reduced,but a dramatic increase presented near the seashore,where the marine sulfate emission and maritime activity pollution were significant.The sulfur concentration and speciation in mature CTLs effectively represented the long-term biological accumulation of atmospheric sulfur pollution in local environment. 相似文献
39.
Sulfur-containing amino acid methionine as the precursor of volatile organic sulfur compounds in algea-induced black bloom 总被引:2,自引:0,他引:2
After the application of methionine, a progressive and significant increase occurred in five volatile organic sulfur compounds (VOSCs): methanethiol (MeSH), dimethyl sulfide (DMS), dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS) and dimethyl tetrasulfide (DMTeS). Even in the untreated control without a methionine addition, methionine and its catabolites (VOSCs, mainly DMDS) were found in considerable amounts that were high enough to account for the water’s offensive odor. However, blackening only occurred in two methionine-amended treatments. The VOSCs production was observed to precede black color development, and the reaching of a peak value for total VOSCs was often followed by water blackening. The presence of glucose stimulated the degradation of methionine while postponing the occurrence of the black color and inhibiting the production of VOSCs. In addition, DMDS was found to be the most abundant species produced after the addition of methionine alone, and DMTeS appeared to be the most important compound produced after the addition of methionine+glucose. These results suggest that methionine acted as an important precursor of the VOSCs in lakes suffering from algea-induced black bloom. The existence of glucose may change the transformation pathway of methionine into VOSCs to form larger molecular weight compounds, such as DMTS and DMTeS. 相似文献
40.
以2001~2010年十年间天水市城区二氧化硫浓度与硫酸盐化速率的监测数据为依据,对城区二氧化硫与硫酸盐化速率的浓度水平和变化规律进行了研究,分析和探讨了二氧化硫浓度与硫酸盐化速率相关性。 相似文献