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501.
针对造纸化学品生产废水具有成分复杂,可生化性差,有机物、NH3-N、Cl-浓度高的特点,采用"初沉池-悬浮生物滤池(A/O)-混凝沉淀池-催化氧化池-硝化滤池"组合工艺对造纸化学品生产废水进行了中试研究,取得很好的处理效果。结果表明,在进水COD为4 832~12 846 mg/L,NH3-N为39~430 mg/L,Cl-为3 200~15 000 mg/L的情况下,处理后出水COD小于500 mg/L,NH3-N小于35 mg/L,主要指标达到污水综合排放标准(GB 8978-1996)三级标准。  相似文献   
502.
Food utilization and growth of the 5th and 6th instar Spodoptera litura Fabricius larvae, and its effect on reproduction potential was evaluated by feeding larvae diets with different doses of Ni for 3 generations. Dose-dependent relationships between Ni levels and food consumption and growth were variable with different larval developmental period and Ni exposure duration. RCR, AD and RGR of the 6th instar larvae were much more affected by Ni exposure than those of 5th instar larvae, and the effects were strongest in the 3rd generation. It was found that RCR was significantly stimulated after 1 and 20 mg kg−1 Ni exposure, while AD was significantly inhibited after 1, 5, 10 and 40 mg kg−1 Ni exposure. However, lower levels of Ni (?5 mg kg−1) significantly increased and higher levels of Ni (?10 mg kg−1) significantly decreased RGR. In 3 successive generations, 10 mg kg−1 Ni significantly increased the ECI and ECD of the 5th instar larvae, and 5 mg kg−1 Ni significantly increased the ECD of the 6th instar larvae. However, ECD were all significantly inhibited with 20 mg kg−1 Ni exposure. Results also revealed that durations of larvae were shortened at low levels of Ni, but extended at high levels of Ni. Fecundity was inhibited by the highest Ni doses in each generation, while improved by low Ni doses in the 3rd generation. Hatching rates in all treatments were significantly decreased in a Ni dose-dependent manner. Study indicated that effects of Ni on these parameters were predominant with the increasing Ni exposure period.  相似文献   
503.
离子色谱法测定油田采出水中总氮和总磷   总被引:1,自引:0,他引:1  
油田采出水经光电催化氧化法处理后,有机物和油被充分降解,用离子色谱法测定 NO3-、PO3-4,5次测定结果的 RSD为3.1%~5.8%。该方法测定出水中 NO3-、PO3-4质量浓度可代表除油处理后原水中总氮、总磷质量浓度,与分光光度法测定原水中总磷、总氮的结果相比,重现性好、耗时少。  相似文献   
504.
A new adsorbent sulfhydryl and carboxyl functionalized magnetite nanocellulose composite [(MB-IA)-g-MNCC] was synthesized by graft co-polymerization of itaconic acid onto magnetite nanocellulose (MNCC) using EGDMA as cross linking agent and K2S2O8 as free radical initiator. The adsorption occurs maximum in the pH 6.5. The best fitted kinetic model was found to be pseudo-second-order kinetics. Therefore the mechanism of Co(II) adsorption onto (MB-IA)-g-MNCC follows ion exchange followed by complexation. The Langmuir model was the best fitted isotherm model for the adsorption of Co(II) onto the (MB-IA)-g-MNCC. Simulated nuclear power plant coolant water samples were also treated with (MB-IA)-g-MNCC to demonstrate its efficiency for the removal of Co(II) from aqueous solutions in the presence of other metal ions. To recover the adsorbed Co(II) ions and also to regenerate the adsorbent to its original state 0.1?M HCl was used as suitable desorbing agent. Six cycles of adsorption-desorption experiments were conducted and was found that adsorption capacity of (MB-IA)-g-MNCC has been decreased from 97.5% in the first cycle to 84.7% in the sixth cycle. Recovery of Co(II) using 0.1?M HCl decreased from 93.2% in the first cycle to 79.3% in the sixth cycle.

Abbreviations: T: absolute temperature; qe: amount adsorbed at equilibrium; qt: amount adsorbed at time t; CELL: cellulose; Co: cobalt; Ce: concentration at equilibrium; CHCl: concentration of HCl; CNaOH: concentration of NaOH; CA: concentrations of acid; CB: concentrations of base; Wg: dry weight of composite; Wi: dry weight of MNCC; DS: energy dispersive spectra; EGDMA: ethylene glycol dimethacrylate; Ce: equilibrium concentration; KL: equilibrium constant; F: Faradays constant; FTIR: Fourier transform infrared spectra; ΔGo: free energy change; KF: Freundlich adsorption capacity; 1/n: Freundlich constant; R: gas constant; D: grafting density; ECo: initial concentration; IA: itaconic acid; IA-g-MNCC: itaconic acid-grafted-magnetite nanocellulose composite; b: Langmuir constant; MNCC: magnetite nanocellulose composite; Q0: Maximum adsorption capacity; (MB-IA)-g-MNCC: 2-mercaptobenzamide modified itaconic acid-grafted-magnetite nanocellulose composite; NC: nanocellulose; pHpzc: Point of zero charge; K2S2O8: potassium peroxy sulphate; k1: pseudo-first-order rate constant; k2: pseudo-second-order rate constant; SEM: scanning Electron Microscope; bs: Sips adsorption capacity; Qs: Sips maximum adsorption capacity; ΔH°: standard enthalpy change; ΔS°: standard entropy change; A: surface area; σ0: surface charge density; 1/ns: surface heterogeneity factor; VSM: vibrating sample magnetometer; V: volume of solution; W: weight of (MB-IA)-g-MNCC; Mcomposite: weight of the composite; XRD: X-ray diffraction  相似文献   

505.
SO2对Mn-Cu-Ce/TiO2低温选择催化还原NO的影响   总被引:1,自引:1,他引:1  
研究了SO2对Mn-Cu-Ce/TiO2选择催化还原 NO 的影响,并采用傅立叶变换红外光谱、x射线衍射光谱及暂态响应技术对Mn-Cu-Ce/TiO2催化剂的SO2中毒机理进行了探讨.结果表明,SO2 可强吸附在Mn-Cu-Ce/TiO2表面的 CuO 活性位上.并生成 CuSO4,由于 CuSO4 在低温时对SCR 反应有抑制作用,因而,催化剂的活性下降;暂态响应实验结果表明,Mn-Cu-Ce/TiO2催化剂上的SCR反应主要遵循 Langmuir-Hinshelwood机理.通过对催化剂进行硫酸化或 NO 预吸附,可以消除SO2对 Mn-Cu-Ce/TiO2的毒害作用.  相似文献   
506.
荀鹏 《四川环境》2013,(6):93-96
介绍了一种新型催化法烟气脱硫技术的技术原理和技术特点,它是一种低温催化氧化技术,能将SO2转化为可直接利用或用于生产其他产品的硫酸,不产生二次污染并具有一定经济效益。该技术目前在硫酸行业和冶炼行业已有一定的推广和应用,针对冶炼尾气的特点,分析该技术在尾气治理工程中的设计要点、运行情况和改进措施等。  相似文献   
507.
以γ-Al2O3为载体,采用等体积浸渍法制备负载型钙钛矿La0.8Ce0.2 Mn0.8 Co0.2 O3/γ-Al2O3催化剂,详细考察了温度、空速、甲苯浓度、水蒸汽等因素对催化剂催化燃烧VOCs(甲苯)性能的影响.结果表明,甲苯的转化率随反应温度的提高而上升;空速越低、水蒸汽含量越少,同一反应温度下甲苯的转化率越高;随甲苯浓度的增大,处理效果表现出先略有提高后降低的趋势;该催化剂随反应时间的增加始终保持了较高的甲苯去除率,稳定性良好.  相似文献   
508.
Batteries sometimes contain precious or toxic substances (e.g. nickel, cobalt, lead, mercury, cadmium). However, the collection and recycling rate of small batteries were low in Japan.We focus on cobalt in lithium ion (Li-ion) batteries and conduct chemical analysis, questioner survey and flow analysis in Japan.Results of chemical analysis showed that the concentration of cobalt in Li-ion batteries was around 20% regardless of the year manufactured or the manufacturer. As a result of the consumer questionnaire survey, it became clear that 70% or more of the small batteries are not being removed when small electronic products are finally disposed. The survey also revealed that recognition of the law and system for collection and recycling of small rechargeable batteries is approximately 30–40%. Substance flow analysis showed that both production and demand for Li-ion batteries (cobalt) have increased during 2002–2010. The collection rate for used Li-ion batteries was about 10% during this period; uncollected batteries were either stored or disposed through incineration and landfill as municipal solid waste.  相似文献   
509.
根据对辽化聚酯一厂生化二沉池出水进行的小试研究结果.结合污水场的自然情况,提出“浮选~生物滤罐~臭氧活性炭催化氧化~快滤”处理技术路线,在辽化聚酯一厂进行了4个多月的中试试验研究。结果表明,经过处理后的出水的COD可降至13mg/L,浊度降至0.4mg/L,油含量降至0,27mg/L,总铁离子降至0.03mg/L,完全达到了循环冷却补充水的要求。  相似文献   
510.
To develop more efficient chemical methods for the demineralization of organic pollutants from water bodies, which one was also mimic to the nature, a degradation of methylene blue by Fe( Ⅲ ) and H2O2 in the absence of light instead of Fe( Ⅱ ) and H2O2 was studied. Results showed that use of Fe ( Ⅲ ) is more promising than Fe( Ⅱ ). The present study reflects that Fenton reaction is more efficient, in the presence of a small amount of salicylic acid is added which is a one of the priority pollutant.  相似文献   
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