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741.
设计全因子实验研究了NO-3-N对填埋10~12 a的矿化垃圾中兼/厌氧甲烷氧化作用的影响.结果表明,兼/厌氧条件下,NO-3-N能促进矿化垃圾中CH4的去除.初始CH4和NO-3-N对CH4去除和N2产生有明显影响,且两者具有交互作用(P<0.05).CH4去除量随着初始CH4体积分数的增加而增加,添加一定含量的NO-3-N能促进CH4去除,同时通入一定体积分数CH4可以明显促进反硝化作用,说明矿化垃圾中NO-3-N还原能与兼/厌氧甲烷氧化耦合.本实验条件下,初始CH4体积分数为30%,NO-3-N含量为110 mg·kg-1时耦合效应较好. 相似文献
742.
743.
阳离子染料废水处理的工艺研究 总被引:6,自引:0,他引:6
首先采用两级物化-电解-吸附工艺对高浓度阳离子染料生产废水进行预处理,再与低浓度生产废水、生活污水混合生化处理,总脱色率和CODcr去除率均可达到99.9%以上,达标排放。 相似文献
744.
采用浸涂-烧结法制备的纳米TiO2光催化剂负载量约为6mg/g载体,催化剂经5次重复使用其催化效果稳定,表明催化剂表面TiO2粉体负载牢固;以高压汞灯为光源,对水中微量间二甲苯的负载型纳米TiO2光催化氧化过程的研究表明:初始浓度在6.68~17.36mg/L的范围内,间二甲苯的光催化反应遵循表现一级反应动力学规律,反应的表现速率常数随溶液初始浓度的增大而减小,半衰期则随初始浓度的增大而增加。 相似文献
745.
采用浸渍法在活性碳纤维(ACF)上负载MnOx制备了MnOx/ACF催化剂,考察了将其用于常温催化氧化二氯甲烷的活性和稳定性。实验结果表明,MnOx负载量(质量分数)为9%的9%MnOx/ACF催化剂活性最高,在反应温度为25 ℃、二氯甲烷质量浓度为600 mg/m3时,反应90 min后9%MnOx/ACF催化剂对二氯甲烷的去除率达71%。9%MnOx/ACF催化剂重复使用5次后对二氯甲烷的去除率仍可达57%,具有较好的重复使用性能。催化剂表面的主要元素为C、O和Mn,且Mn主要以Mn4+形式存在。使用后的催化剂中存在二氯甲烷降解的中间产物甲酸盐和甲氧基物种,说明二氯甲烷已被成功降解。 相似文献
746.
采用催化氧化技术对某石化企业苯胺、硝基苯等生产装置和罐区的含氮挥发性有机物(NVOCs)废气进行集中处理,建成了一套20 000 Nm~3/h规模的安全高效处理装置。采用自主研发的WSH-2N型蜂窝状Pt-Pd-Ce催化剂,在高效氧化有机物的同时,高选择性地将有机氮转化为N_2。运行结果表明,净化气非甲烷总烃质量浓度低于15 mg/m~3,非甲烷总烃去除率大于99%,NO_x质量浓度低于10 mg/m~3,苯、苯胺、硝基苯、环己烷等特征有机污染物浓度均低于检出限,各项指标优于国内外现有技术。 相似文献
747.
748.
Observations of Atmospheric Nitrogen and Phosphorus Deposition During the Period of Algal Bloom Formation in Northern Lake Taihu,China 总被引:4,自引:1,他引:4
Cyanobacterial blooms in Lake Taihu occurred at the end of April 2007 and had crucial impacts on the livelihood of millions
of people living there. Excessive nutrients may promote bloom formation. Atmospheric nitrogen (N) and phosphorus (P) deposition
appears to play an important role in algal bloom formation. Bulk deposition and rain water samples were collected respectively
from May 1 to November 30, 2007, the period of optimal algal growth, to measure the bulk atmospheric deposition rate, wet
deposition rate, and dry deposition rate for total nitrogen (TN; i.e., all species of nitrogen), and total phosphorus (TP;
i.e., all species of phosphorus), in northern Lake Taihu, China. The trends of the bulk atmospheric deposition rate for TN
and the wet deposition rate for TN showed double peaks during the observation period and distinct influence with plum rains
and typhoons. Meanwhile, monthly bulk atmospheric deposition rates for TP showed little influence of annual precipitation.
However, excessive rain may lead to high atmospheric N and P deposition rates. In bulk deposition samples, the average percentage
of total dissolved nitrogen accounting for TN was 91.2% and changed little with time. However, the average percentage of total
dissolved phosphorus accounting for TP was 65.6% and changed substantially with time. Annual bulk atmospheric deposition rates
of TN and TP during 2007 in Lake Taihu were estimated to be 2,976 and 84 kg km−2 a−1, respectively. The results showed decreases of 34.4% and 78.7%, respectively, compared to 2002–2003. Annual bulk deposition
load of TN for Lake Taihu was estimated at 6,958 t a−1 in 2007 including 4,642 t a−1 of wet deposition, lower than the values obtained in 2002–2003. This may be due to measures taken to save energy and emission
control regulations in the Yangtze River Delta. Nevertheless, high atmospheric N and P deposition loads helped support cyanobacterial
blooms in northern Lake Taihu during summer and autumn, the period of favorable algal growth. 相似文献
749.
As a means to remediate soil contaminated by polycyclic aromatic hydrocarbons, we investigated a combined process involving
ethanol washing followed by a Fenton oxidation reaction. Artificial loamy soil was contaminated with various representative
polycyclic aromatic hydrocarbons (i.e., fluorene, anthracene, pyrene, benzo(b)fluoranthene, or benzo(a)pyrene) at concentrations
ten times higher than regulatory soil standards of The Netherlands or Canada, and then washed four times in ethanol, which
reduced the concentration of polycyclic aromatic hydrocarbon contamination to below the regulatory standard. Fenton oxidation
of ethanol solutions containing anthracene, benzo(a)pyrene, pyrene, acenaphthylene, acenaphthene, benz(a)anthracene, benzo(j)fluoranthene,
or indeno(1,2,3-cd)pyrene showed a removal efficiency of 73.3%–99.0%; by contrast, solutions containing naphthalene, fluorene,
fluoranthene, phenanthrene, or benzo(b)fluoranthene showed a removal efficiency of 9.6%–27.6%. Since each of the nonremediated
polycyclic aromatic hydrocarbons, excluding benzo(b)fluoranthene, are easily biodegradable, these results indicate that the
proposed treatment can be successfully applied to polycyclic aromatic hydrocarbon-contaminated soil that does not contain
high concentrations of benzo(b)fluoranthene. The main reaction products resulting from Fenton oxidation of ethanol solutions
containing anthracene or benz(a)anthracene were anthraquinon or benz(a)anthracene-7,12-dione, respectively; while 1,8-naphthalic
anhydride was produced by solutions of acenaphthylene and acenaphthene, and 9-fluorenone by a fluorene solution.
Received: June 9, 1998 / Accepted: March 24, 1999 相似文献
750.
采用三维电极电Fenton氧化法处理实际染料废水,探究了染料废水处理效果的影响因素。实验结果表明:以钌铱镀层钛电极为阳极、不锈钢板为阴极、粉末活性炭为颗粒电极,在粉末活性炭投加量为2.0 g/L、电流密度为0.5 mA/mm2、极板间距为3 cm、pH为2.0、硫酸亚铁投加量为0.50 g/L的最优工艺条件下,反应2 h后COD、TOC、氨氮、色度的去除率达到最大,分别为62.80%、41.15%、42.48%和95.00%;粉末活性炭作为颗粒电极可使染料废水COD去除率提高18个百分点;重复使用10次的处理效果与第2次基本持平。 相似文献