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241.
文章采用自主研发的一体化平板膜靛蓝回收装置对印染废水进行了小试研究。此工艺采用投加H2O2氧化染液的方式析出靛蓝结晶并采用平板膜处理的方式不断浓缩靛蓝并将浓缩液回用于染色工段,保证了染料回用的效果。对装置中预处理单元,氧化单元,膜过滤单元等主.要参数进行了优化。研究结果表明.该装置氧化单元H2O2最佳投加量为15ml/L,最佳氧化pH=3;最佳过膜条件pH=4,连续曝气,开停比4:3;膜清洗采用水力冲洗后NaC10浸泡2h的方法,通量恢复近100%。在该最佳工况下,装置不仅能够高效回收靛蓝染料,回收效率达到99.5%,同时废水水质得到极大改善,SS平均去除93.9%,浊度下降100%,色度下降98.4%。 相似文献
242.
Hydrous manganese dioxide (HMO) synthesized by redox of potassium permanganate and hydrogen peroxide was used as an adsorbent for Pb(Ⅱ) removal.The specific surface area,pore volume and BJH pore diameter of the HMO were 79.31m2/g,0.07cm3/g and 3.38 nm,respectively.The adsorption equilibrium at 298K could be well described by the Langmuir isotherm equation with q max value of 352.55mg/g.The negative values of G and the positive values of H and S indicated the adsorption process was spontaneous and endothermic.The pseudo second-order equation could best fit the adsorption data.The value of the calculated activation energy for Pb(Ⅱ) adsorption onto the HMO was 38.23 kJ/mol.The uptake of Pb(Ⅱ) by HMO was correlated with increasing surface hydroxyl group content and the main adsorbed speciation was PbOH+.The final chemical state of Pb(Ⅱ) on the surface of HMO was similar to PbO.HMO was a promising candidate for Pb(Ⅱ) removal from aqueous solution. 相似文献
243.
244.
随着近几年中小城市发展进程的加快,城市中日益暴露出各方面的问题与弊端,污水治理问题显得尤为突出和严重。污水排放大量增加对我国中小城市水环境造成了严重的污染和破坏,因此对污水处理技术的选择与考量十分迫切。基于我国国情,我国是发展中国家,财力有限。因此用于基础设施上的资金在大城市和中小城镇之间的分配比重严重失衡,中小城镇污水的处理率相对较低。这就决定了中小城镇在选择污水处理技术时,首先要考虑的因素必须是经济、高效、节能和简便易行。 相似文献
245.
Photo-production of dissolved inorganic carbon (DIC) from chromophoric dissolved organic matter (CDOM) is an important transformation process in marine carbon cycle, but little is known about this process in Chinese coastal systems. This study investigated an estuarine water sample and a coastal seawater sample from the subtropical waters in southeast of China. Water samples were exposed to natural sunlight and the absorption and fluorescence of CDOM as well as the DIC concentration were measured in the summer of 2009. The estuarine water had higher CDOM level, molecular weight and proportion of humic-like fluorescent components than the seawater that exhibited abundant tryptophan-like fluorescent component. After a 3-day irradiation, the CDOM level decreased by 45% in the estuarine water and 20% in the seawater, accompanied with a decrease in the molecular weight and aromaticity of DOM which was inferred from an increase in the absorption spectral slope parameter. The photo-degradation rates of all the five fluorescent components were also notable, in particular two humic-like components (C4 and C5) were removed by 78% and 69% in the estuarine water and by 69% and 56% in the seawater. The estuarine water had a higher photo-production rate of DIC than the seawater (4.4 vs. 2.5 μupmol/(L.day)), in part due to its higher CDOM abundance. The differences in CDOM compositions between the two types of waters might be responsible for the higher susceptibility of the estuarine water to photo-degradation and hence could also affect the photo-production process of DIC. 相似文献
246.
粉煤灰改性吸附材料的研究 总被引:15,自引:0,他引:15
分析了粉煤灰改性的物质基础,阐述了当前改性的主要方法,在此基础上,笔者用燃烧、Na(OH)2溶液改性粉煤灰制得类沸石吸附剂的比表面积为112.6m^2/g、孔隙率为83.1%,是改性前的40.22和1.67倍。用此类沸石吸附剂来处理浓度为200mg/1的模拟含铅废水,去除率为84.87%、吸附容量为33.94mg/g,分别是改性前的31.13、3.13倍,处理效果优于市售一级活性炭。并用0.1M的HCl溶液和饱和NaCl溶液再生此吸附剂,解吸率达到了98%以上,此再生的类沸石吸附剂处理含铅废水的去除率也达到了83%以上。另外也研究了用酸改性粉煤灰来处理造纸废水,并设计了工艺流程、确定了工艺参数,处理效果令人满意。最后提出了当前应用改性粉煤灰处理废水和废气中存在的问题及今后研究的重点。 相似文献
247.
Di Meng Wei Jiang Jing Li Lin Huang Lixin Zhai Liyuan Zhang 《Journal of environmental science and health. Part. B》2019,54(4):336-343
In recent decades, biodegradation has been considered a promising and eco-friendly way to eliminate organophosphorus pesticides (OPs) from the environment. To enrich current biodegrading-enzyme resources, an alkaline phosphatase (AP3) from Bacillus amyloliquefaciens YP6 was characterized and utilized to test the potential for new applications in the biodegradation of five broad-spectrum OPs. Characterization of AP3 demonstrated that activity was optimal at 40?°C and pH 10.3. The activity of AP3 was enhanced by Mg2+, Ca2+, and Cu2+, and strongly inhibited by Mn2+, EDTA, and L-Cys. Compared to disodium phenyl phosphate, p-nitrophenyl phosphate (pNPP) was more suitable to AP3, and the Vm, Km, kcat, kcat/Km values of AP3 for pNPP were 4,033?U mg?1, 12.2?mmol L?1, 3.3?×?106 s?1, and 2.7?×?108 s?1mol?1L, respectively. Degradation of the five OPs, which included chlorpyrifos, dichlorvos, dipterex, phoxim, and triazophos, was 18.7%, 53.0%, 5.5%, 68.3%, and 96.3%, respectively, after treatment with AP3 for 1?h. After treatment of the OP for 8?h, AP3 activities remained more than 80%, with the exception of phoxim. It can be postulated that AP3 may have a broad OP-degradation ability and could possibly provide excellent potential for biodegradation and bioremediation in polluted ecosystems. 相似文献
248.
Meng Li Xiaolan Yu Fei Wang Chao Zhai Wei Shen Xianhong Yu 《Journal of environmental science and health. Part. B》2013,48(10):691-697
In the present study, recombinant organophosphorus hydrolase OPHC2 was successfully produced by Yarrowia lipolytica and purified. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blot analyses showed a major polypeptide band of 36 kDa. The purified enzyme was optimally active at 65°C and pH 8.5 and also displayed good thermal and pH stability using methyl parathion (O,O-dimethyl-O-4-p-nitrophenyl phosphorothioate) as a substrate. Moreover, as Y. lipolytica is a non-pathogenic, generally regarded as safe (GRAS) yeast, the cell culture supernatant can be used directly on vegetables and fruits that are contaminated by organophosphorus pesticides. 相似文献
249.
根据脱硫灰及石膏的特性,在无挡板平底圆筒搅拌槽内,对脱硫石膏中的杂质进行完全离底悬浮分离实验,研究结果表明,完全离底悬浮搅拌时,悬浮高度比越低,越有利于杂质分离。对于直径D≥24cm的搅拌槽,当桨叶离底高度cb=4cm,桨径槽比d/D=0.65,杂质分离效率叼最高,约82%;当直径D=20cm时,杂质分离效率η随d/D的增大而增大,桨叶离底间距减小,杂质分离效率受d/D影响程度减小;当桨叶离底高度cb=4cm时,随着搅拌槽直径D的增大,杂质分离效率总体呈现增大趋势,降低桨叶离底高度cb杂质分离效率变化较大;进行完全离底悬浮分离后,石膏纯度提高。 相似文献
250.
研究脱硫灰中杂质对石灰石脱硫活性的影响具有重要意义,采用烟气湿法脱硫用石灰石粉反应速率的测定方法,使用瑞士万通902智能电位滴定仪,分析了SiO2、Al2O3、Fe2O3、CaSO3与MgO等脱硫灰中5种杂质对石灰石脱硫活性的影响.结果表明,在实验浓度范围内,SiO2、Al2O3、CaSO3的加入在一定程度上促进了石灰石的溶解,而MgO、Fe2O3的加入在一定程度上抑制了石灰石的溶解.将脱硫灰与石灰石掺合作脱硫剂时,要综合考虑这5种杂质对石灰石溶出的影响,选择适宜的脱硫灰和石灰石掺合比. 相似文献