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991.
Flower-, wire-, and sheet-like MnO2-deposited diatomites have been prepared using a hydrothermal method with Mn(Ac)2, KMnO4 and/or MnSO4 as Mn source and diatomite as support. Physical properties of the materials were characterized by means of numerous analytical techniques, and their behaviors in the adsorption of chromium(VI) were evaluated. It is shown that the MnO2-deposited diatomite samples with different morphologies possessed high surface areas and abundant surface hydroxyl groups (especially the wire-like MnO2/diatomite sample). The wire-like MnO2/diatomite sample showed the best performance in the removal of Cr(VI), giving the maximum Cr(VI) adsorption capacity of 101 mg/g. 相似文献
992.
Flower-, wire-, and sheet-like MnO2-deposited diatomites have been prepared using a hydrothermal method with Mn(Ac)2, KMnO4 and/or MnSO4 as Mn source and diatomite as support. Physical properties of the materials were characterized by means of numerous analytical techniques, and their behaviors in the adsorption of chromium(VI) were evaluated. It is shown that the MnO2-deposited diatomite samples with different morphologies possessed high surface areas and abundant surface hydroxyl groups (especially the wire-like MnO2/diatomite sample). Thewire-like MnO2/diatomite sample showed the best performance in the removal of Cr(VI), giving the maximum Cr(VI) adsorption capacity of 101 mg/g. 相似文献
993.
Qian Zhao Hongjun Han Baolin Hou Haifeng Zhuang Shengyong Ji Fang Fang 《环境科学学报(英文版)》2014,26(11):2231-2239
A system combining granular activated carbon and powdered activated carbon technologies along with shortcut biological nitrogen removal (GAC-PACT-SBNR) was developed to enhance total nitrogen (TN) removal for anaerobically treated coal gasification wastewater with less need for external carbon resources. The TN removal efficiency in SBNR was significantly improved by introducing the effluent from the GAC process into SBNR during the anoxic stage, with removal percentage increasing from 43.8%49.6% to 68.8%-75.8%. However, the TN removal rate decreased with the progressive deterioration of GAC adsorption. After adding activated sludge to the GAG compartment, the granular carbon had a longer service-life and the demand for external carbon resources became lower. Eventually, the TN removal rate in SBNR was almost constant at approx. 43.3%, as compared to approx. 20.0% before seeding with sludge. In addition, the production of some alkalinity during the denitrification resulted in a net savings in alkalinity requirements for the nitrification reaction and refractory chemical oxygen demand (COD) degradation by autotrophic bacteria in SBNR under oxic conditions. PACT showed excellent resilience to increasing organic loadings. The microbial community analysis revealed that the PACT had a greater variety of bacterial taxons and the dominant species associated with the three compartments were in good agreement with the removal of typical pollutants. The study demonstrated that pre-adsorption by the GAC-sludge process could be a technically and economically feasible method to enhance TN removal in coal gasification wastewater (CGW). 相似文献
994.
双甘膦废水中含有高浓度总磷、有机磷、甲醛、氰化物、氨氮、COD,运用三效蒸发+强氧化+两级化学除磷+UASB+兼氧+好氧组合处理双甘膦废水。研究结果表明双甘膦废水排放满足《污水综合排放标准》(G88978—1996)二级排放标准。 相似文献
995.
《Journal of Manufacturing Processes》2014,16(4):494-502
A new mass finishing technology, namely drag finishing of brass (Cu–30 wt.% Zn) rings with fluidized abrasives, is reported. A new equipment, which combines the typical features of the drag finishing machines to hold the workpiece with the moving abrasives of fluidized beds, was designed. The equipment was validated by performing several experimental tests varying rotary speed and processing time. The evolution of the surface morphology of the workpieces, their mass loss and dimensional accuracy after processing were assessed after each finishing step. The designed equipments allowed to finish with a high level of accuracy and in short time range the brass rings. Material removals and out-of-tolerances of the workpieces could be limited once the appropriate settings of the process were selected. Low energy requirements, lack of any residuals after processing and facile operations make the fluidized bed assisted drag finishing industrially sustainable and very promising in several manufacturing domains. 相似文献
996.
烟气污染物大致分为气态污染物(SOx和NOx)、颗粒物和重金属.烟气综合治理的研究基础应先研究三类污染物之间、污染物与常用处理工艺之间以及不同污染物处理工艺之间的相互影响和作用.烟气污染综合治理的思路可归纳为工艺直接组合、集成控制与同时处理,其中以同时处理为最优.同时脱硫脱硝的研究趋势为等离子体技术与活性炭吸附技术,同时除尘脱汞的研究趋势则为汞在除尘过程中的迁移转化和汞的氧化剂和氧化方法的研究. 相似文献
997.
998.
用甲基橙作为胁迫因子,研究了甲基橙对稀脉萍叶片过氧化物酶活性、可溶性蛋白含量和叶绿素含量的影响,并采用稀脉萍去除甲基橙。结果表明:随着甲基橙浓度的增加,过氧化物酶活性呈先上升后下降的趋势,当甲基橙浓度为140mg/L时,过氧化物酶活性达到最高值。当甲基橙浓度>100mg/L,可溶性蛋白含量急速下降。叶绿素含量和叶绿素a/b比值均随甲基橙浓度的升高而降低。当甲基橙浓度为20 mg/L时,稀脉萍对甲基橙的去除需经10 d的延滞期,24 d后去除率达89.6%。 相似文献
999.
在温度30℃、pH为7、硫氮比为5/3、厌氧条件下,对比研究了不同n(NO-3-N)/n(NO-2-N)对荧光假单胞菌和铜绿假单胞菌混培养菌同步脱氮除硫影响.随着n(NO-3-N)/n(NO-2-N)减小,荧光假单胞菌、铜绿假单胞菌对NOx-N去除率逐渐增高,而S2-去除率却依次减少,混培养菌对NOx-N去除效率先增加后趋于平稳.n(NO-3-N)/n(NO-2-N)对混培养菌去除S2-几乎没有影响.荧光假单胞菌能迅速将NO-3-N转化为NO-2-N,但NO-2-N转为N2却相对缓慢,培养液中出现NO-2-N累积;而铜绿假单胞菌将NO-2-N还原N2的能力明显比荧光假单胞菌强,培养液未反应的NOx-N以NO-3-N为主,未出现NO-2-N累积.混培养菌对NOx-N转化的情况介于荧光假单胞菌与铜绿假单胞菌之间.荧光假单胞菌同时获得较高NOx-N、S2-去除的n(NO-3-N)/n(NO-2-N)为5/5,铜绿假单胞菌为10/0,混培养菌为5.0/5.0.混培养菌对NOx-N、S2-的同步去除效果优于单菌株荧光假单胞菌和铜绿假单胞菌. 相似文献
1000.
光电Fenton技术处理污泥深度脱水液研究 总被引:4,自引:3,他引:1
以光电Fenton技术处理污泥深度脱水液,试验结果表明,利用光电Fenton技术能快速有效地去除废水中的污染物.在最佳试验条件下,即初始pH为3.0,H2O2投加量65.3 mmol·L-1,FeSO4投加量6.53 mmol·L-1[n(Fe2+)∶n(H2O2)=1∶10),外加电压为7.5 V时,经光电Fenton技术处理20 min后污泥脱水液的COD去除率可以达到59.0%.同时TOC、TN、NH+4-N及TP的去除率也分别达到了49.3%、20.6%、73.6%和96.5%.该项研究为光电Fenton技术在废水处理中的应用提供了参考. 相似文献