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841.
电化学氧化对罗丹明B脱色的研究   总被引:7,自引:0,他引:7  
以网状钛涂钌材料作为阳极,网状不锈钢作为阴极,研究了在阴、阳极室无隔膜电解槽内模拟罗丹明B废水电催化脱色效果。研究结果表明,电解电压、电解质(Na2SO4)浓度、反应时间、溶液的pH、NaCl的投加量对罗丹明B的脱色有较大影响。在Na2SO4浓度为0.1mol/L时,外加电压8V,电解100min,20mg/L罗丹明B溶液的脱色率可以达到90.5%;在上述溶液中NaCl浓度达到20mg/L时,只需电解30min,罗丹明B的脱色率几乎达到100%。  相似文献   
842.
Fe2+-H2O2催化氧化加混凝处理苯酚磺酸废水   总被引:2,自引:0,他引:2  
采用H2O2-Fe^2 催化氧化-混凝联合工艺对苯酚磺酸(PSA)废水进行了试验研究,对H2O2和Fe^2 的投加量、pH值、温度(T)、时间(t)等工艺参数进行了优选。结果表明,在H2O2/COD0(g/g)=1.5,H2O2/Fe^2 (moL/moL)=10:1、pH=3.0-4.0、T=30℃、t=30min的条件下,COD为1198mg/L的PSA废水经该工艺处理,COD去除率达94%。试运行结果表明,其出水水质达到国家排放标准(GB8978-1996)。  相似文献   
843.
采用低压空气氧化法使废碱液中的S^2-,SR-转变为S2O3^2-,RSSR,该过程能否成功操作取决于温度,压力和空气与水的接触,尤其是空气与水的传质速度将会较大的影响硫化物的氧化去除速率和空气中氧气的利用率。  相似文献   
844.
光催化氧化法的影响因素和发展趋势   总被引:22,自引:1,他引:22  
概述了光催化氧化有机物的机理,讨论了影响其反应速率的诸多因素和如催化剂,光强,有机物浓度,PH值,温度,外加氧化剂和盐等,探讨了提高反应效率的途径,并指出了今后光催化氧化法在水处理中的应用与研究方向。  相似文献   
845.
啤酒废水处理技术的应用   总被引:10,自引:1,他引:10  
左永泉 《环境工程》2000,18(1):26-28
采用厌氧(UASB)+接触氧化工艺处理啤酒生产高浓度有机废水,处理后的各项指标完全达到了国家规定的排放标准。对废水综合处理系统的调试、运行过程进行了技术总结,并就其工艺要点进行了探讨。  相似文献   
846.
高速公路生活区污水处理初探   总被引:8,自引:0,他引:8  
葛梅 《交通环保》1999,20(5):20-21,26
通过对高速公路生活区污水特点的分析及各种生活污水处理的工艺比较向人们提供一种适合高速公路生活区污水处理的工艺。  相似文献   
847.
Microbial electrosynthesis system (MES) is a promising method that can use carbon dioxide, which is a greenhouse gas, to produce methane which acts as an energy source, without using organic substances. However, this bioelectrical reduction reaction can proceed at a certain high applied voltage when coupled with water oxidation in the anode coated with metallic catalyst. When coupled with the oxidation of HS to SO42−, methane production is thermodynamically more feasible, thus implying its production at a considerably lower applied voltage. In this study, we demonstrated the possibility of electrotrophic methane production coupled with HS oxidation in a cost-effective bioanode chamber in the MES without organic substrates at a low applied voltage of 0.2 V. In addition, microbial community analyses of biomass enriched in the bioanode and biocathode were used to reveal the most probable pathway for methane production from HS oxidation. In the bioanode, electroautotrophic SO42− production accompanied with electron donation to the electrode is performed mainly by the following two steps: first, incomplete sulfide oxidation to sulfur cycle intermediates (SCI) is performed; then the produced SCI are disproportionated to HS and SO42−. In the biocathode, methane is produced mainly via H2 and acetate by electron-accepting syntrophic bacteria, homoacetogens, and acetoclastic archaea. Here, a new eco-friendly MES with biological H2S removal is established.  相似文献   
848.
气浮-生物接触氧化法深度处理再生纸生产废水   总被引:7,自引:0,他引:7  
姚来银 《环境工程》2003,21(3):19-20
在化学絮凝 气浮方法基础上 ,深度处理再生纸生产废水生物接触氧化法。运行情况表明 :该治理工艺处理效率高 ,中间水回用连续稳定 ,排放废水稳定达标 ,生产废水回用率达 85 %以上  相似文献   
849.
Dissolved oxygen (DO) concentration is regarded as one of the crucial factors to influence partial nitrification process. However, achieving and keeping stable partial nitrification under different DO concentrations were widely reported. The mechanism of DO concentration influencing partial nitrification is still unclear. Therefore, in this study two same sequencing batch reactors (SBRs) cultivated same seeding sludge were built up with real-time control strategy. Different DO concentrations were controlled in SBRs to explore the effect of DO concentration on the long-term stability of partial nitrification process at room temperature. It was discovered that ammonium oxidation rate (AOR) was inhibited when DO concentration decreased from 2.5 to 0.5 mg/L. The abundance of Nitrospira increased from 1011.5 to 1013.7 copies/g DNA, and its relative percentage increased from 0.056% to 3.2% during 190 operational cycles, causing partial nitrification gradually turning into complete nitrification process. However, when DO was 2.5 mg/L the abundance of Nitrospira was stable and AOB was always kept at 1010.7 copies/g DNA. High AOR was maintained, and stable partial nitrification process was kept. Ammonia oxidizing bacteria (AOB) activity was significantly higher than nitrite oxidizing bacteria (NOB) activity at DO of 2.5 mg/L, which was crucial to maintain excellent nitrite accumulation performance.  相似文献   
850.
The catalytic ozonation treatment of secondary biochemical effluent for papermaking wastewater by Ag-doped nickel ferrite was investigated. Ag-doped catalysts prepared by sol-gel method were characterized, illustrating that Ag entirely entered the crystalline of NiFe2O4 and changed the surface properties. The addition of catalyst enhanced the removal efficiency of chemical oxygen demand and total organic carbon. The results of gas chromatography-mass spectrometer, ultraviolet light absorbance at 254 nm and three-dimensional fluorescence excitation-emission matrix suggested that aromatic compounds were efficiently degraded and toxic substances, such as dibutyl phthalate. In addition, the radical scavenging experiments confirmed the hydroxyl radicals acted as the main reactive oxygen species and the surface properties of catalysts played an important role in the reaction. Overall, this work validated potential applications of Ag-doped NiFe2O4 catalyzed ozonation process of biologically recalcitrant wastewater.  相似文献   
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