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541.
湿式过氧化氢氧化处理高浓度染料废水的工艺研究 总被引:10,自引:0,他引:10
采用湿式过氧化氢氧化-铁屑过滤-混凝技术处理高浓度偶氮染料废水,用难生化降解的甲基橙进行模拟试验。实验结果表明,该工艺COD和色度的去除率分别高达85%和99%。湿式过氧化氢氧化处理过程受温度、硫酸投量、Fe^2 投量、H2O2投量的影响,反应温度对COD和色度的去除率影响较大,COD去除率的增加与H2O2投量成正比,色度的去除率随COD的增高而增大。 相似文献
542.
氟化氢对植物抗氧化酶活性的影响 总被引:9,自引:0,他引:9
采用人工熏气方法研究HF污染条件下大豆和菜豆叶片中4种抗氧化酶的活性变化,结果表明它们对氟的敏感性差异很大:超氧化物歧化酶最为敏感,抗坏血酸过氧化物酶和非特异性过氧化物酶次之,而过氧化氢酶活性基本无变化,就两种供试植物而言,大豆的抗氧化酶对氟更为敏感;就植物生长阶段而言,开花期的抗氧化酶对氟的敏感性较苗期为大。在此基础上提出,氟污染环境中植物SOD、A-POD和N-POD的活性受抑与植物氟害有关。 相似文献
543.
A method for rapidly determining potential H+ production by sulfide oxidation with H2O2 in mine-spoil materials has been tested. Measuring pH 6 h after the addition of the H2O2 in a 1:20 sample-solution (w/v) ratio, seems to be an adequate period for most of the samples. The method was applied to
spoil samples, being recommended as a measure of the potential of a material to acidify the environment, in the first steps
of characterization of the tailing's materials. The same procedure after grinding can also indicate the inherent ability to
neutralize the acidity. This will allow the selection of the most suitable materials to be mixed in the spoil with the sulfide-rich
ones, facilitating the later field work. 相似文献
544.
545.
The future widespread use of hydrogen as an energy carrier brings in safety issues that have to be addressed before public acceptance can be achieved. The prediction of the consequences of a major accident release of hydrogen into the atmosphere or the contamination of high-pressure hydrogen storage facilities by air entrainment requires a good knowledge of the explosion parameters of hydrogen–air mixtures. The present paper reviews and comments on the current knowledge of dynamic parameters of hydrogen detonation for hazard assessment. The major problem that remains to be resolved involves the understanding of the effect of turbulence on the cellular detonation structure, the propagation of high-speed deflagrations and the transition from deflagration to detonations. It is recommended that future research should be aimed towards experiments that permit the quantitative understanding of the mechanisms of high-speed turbulent combustion rather towards large-scale tests in complex geometries where minimal quantitative information of fundamental significance could be extracted. In spite of its wide flammability and sensitivity to ignition and detonation initiation, it is felt that hydrogen can be produced, stored and handled safely with the appropriate considerations in the design of the hydrogen facilities. 相似文献
546.
547.
Stambuk-Giljanović N 《Environmental monitoring and assessment》2008,140(1-3):109-117
The objective of this paper is to study the hydrological characteristics and origin of the hydrogen sulphide spring water
from the Split spa in Southern Croatia in 1987, 1988 and 2003. This paper presents the results of monitoring the content of
chlorides and hydrogen sulphide as well as the temperature of the hydrogen sulphide spring water. Since the hydrogen sulphide
content during the dry periods significantly differs from the hydrogen sulphide content during rainy periods, this paper also
compares the results obtained for those two periods. Under the influence of great quantities of rainfall during cold periods
(winter and the beginning of spring) the ratio between seawater and surface water changes and thus the reduction of chlorides
and other minerals occurs. The lowered temperature also reduces hydrogen sulphide which can disappear completely. The concentration
of 12‰ chlorides (76–94.4% days/year) and 12 mg/L hydrogen sulphide (66.7–88.9% days/year) has been taken as a limit value
between water with a normal typical content and water in cold rainy periods. According to the monitoring results it can be
concluded that hydrogen sulphide spring water consists of seawater and hydrogencarbonate surface water with a fairly constant
content during dry periods while the hydrogencarbonate content increases during rainy periods. 相似文献
548.
活性炭/H2O2催化氧化-絮凝法预处理化工有机废水 总被引:5,自引:3,他引:2
用活性炭作催化剂、H2O2作氧化剂催化氧化预处理高浓度化工有机废水,考察了各种因素对COD去除率的影响。实验结果表明,在H2O2加入量为0.8mL/L、活性炭与H2O2质量比为0.7、废水pH为4的条件下,反应120min后,调废水pH至8,加入絮凝剂聚合氯化铝进行絮凝沉淀,废水COD去除率达70%以上,色度去除率达80%以上。通过色谱-质谱仪对处理前后废水中的有机物进行分析,初步探讨了活性炭/H2O2催化氧化-絮凝法预处理化工有机废水的作用机理。 相似文献
549.
This paper assessed the composition of waste water effluent generated by a Petrochemical industry and a treatment system developed to improve the quality of the discharge water. Parameters as pH, COD, TSS chloride and lead ions were analysed and treated comparatively using hydrogen peroxide. At pH 8.0 post treatment analysis showed a COD – 96 mg/l TSS – 48 mg/l Cl – 798.75 mg/l and Pb2+ – 2 mg/l for treatment D where 40 g/l of alum was used on 30% solution of H2O2 compared to systems A-C. Process treatment included activated clay with sodium ion resin which at pH 6.8 had COD – 52 mg/l, TSS – 10 mg/l, Cl – 510 mg/l and Pb2+ – 0.070 mg/l. This system has an overall efficiency of 79.0% TSS, 45.83% COD, 97.5% Pb2+ and 36.1% Cl reduction. Characteristics obtained for the study has a higher efficiency compared with FEPA and WHO standard for similar industrial water treatment. 相似文献
550.
一起双氧水储罐爆炸事故的原因调查 总被引:2,自引:1,他引:1
错将水玻璃加到双氧水中,致使双氧水储罐爆炸,炸飞的罐体挂断供电线路,全厂断电停产23 h,经济损失100多万元,无人员伤亡. 相似文献