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91.
Yi‐Hung Chen Ching‐Yuan Chang Wei‐Ling Su Chun‐Yu Chiu Yue‐Hwa Yu Pen‐Chi Chiang Chiung‐Fen Chang Je‐Lueng Shie Chyow‐San Chiou Sally IM Chiang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(1):68-75
This study investigates the ozonation of CI Reactive Black 5 (RB5) by using the rotating packed bed (RPB) and completely stirred tank reactor (CSTR) as ozone contactors. The RPB, which provides high gravitational force by adjusting the rotational speed, was employed as a novel ozone contactor. The same ozone dosage was separately introduced into either the RPB or the CSTR for the investigation, while the experimental solution was continuously circulated within the apparatus consisting of the RPB and CSTR. The decolorization and mineralization efficiencies of RB5 in the course of ozonation are compared for these two methods. Moreover, the dissolved and off‐gas ozone concentrations were simultaneously monitored for the further analysis. As a result, the ozone mass transfer rate per unit volume of the RPB was significantly higher because of its higher mass transfer coefficient and gas–liquid concentration driving force. Furthermore, ozonation kinetics was found to be independent of the gravitational magnitude of an ozone gas–liquid contactor. Therefore, the results suggest employing RPBs as ozone‐contacting devices with the advantage of volume reduction. The experimental results, which can be used for further modeling of the ozonation process in the RPB, also show the requirement of correct design for the RPB. Consequently, the present study is useful for the understanding of practical application of RPBs. Copyright © 2004 Society of Chemical Industry 相似文献
92.
Huai Wen-xin Wuhan University of Hydraulic & Electric Engineering Wuhan Hubei P.R.China Prof.Li Wei 《水动力学研究与进展(B辑)》1993,(3)
Turbulence represents an essential aspect in atmospheric and oceanic circulations.In particu-lar,it is a preponderant factor in the dispersion of pollutants of artificial or natural origin.Thevertical turbulent jets,plumes and buoyant jets discharging into static environment is one of themost important and basic flow patterns related with the environment pollution.These flows havenumerous important applications,for example,thrust augmentors,waste disposal plumes fromstacks and combustion systems,and significant problems of turbulent diffusion. 相似文献
93.
Dan C. DeBorde William W. Woessner Bruce Lauerman Patrick Ball 《Water research》1998,32(12):3781-3785
At the present time, somatic and male-specific coliphage and human enterovirus groups are being considered as indicators of possible pathogenic human enteric virus contamination from fecal contamination. A primary attribute for any indicator of fecal contamination is its prevalence at the source and in associated ground water. It must be consistently found in the source material at concentrations that are measurable with available techniques. Over a period of ten months, male-specific and somatic coliphage ranged from 7000 to 4,000,000 PFU/L in the effluent from a multi-user septic-tank. Unlike the values determined for septic-tank effluent, coliphage concentrations measured in ground water over this same period only varied by five-fold. Coliphage concentration in ground water under the down-gradient edge of the drainfield contained 1000 PFU/L. This concentration decreased at −1 log10/5 m during 17.4 m of ground-water transport. From these data, coliphage concentrations in septic-tank effluent seem sufficient to allow their use as indicators of fecal contamination in ground water. 相似文献
94.
液相添加剂对PTCR陶瓷电性能的影响 总被引:3,自引:2,他引:1
液相添加剂AST(Al2O3+SiO2+TiO2)对BaTiO3陶瓷材料电性能的影响很大,随着Al2O3含量的增加,材料的电性能降低;SiO2、TiO2的物理特性对材料电性能影响较大;过量TiO2对材料PTC效应有重要影响,适当过量TiO2含量,可得到性能优良的PTCR陶瓷。 相似文献
95.
用废旧橡胶生产精细胶粉的空气涡轮制冷低温粉碎法 总被引:1,自引:0,他引:1
利用先进的空气涡轮制冷系统,在低温条件下,将废旧橡胶进行冷冻,粉碎,制成60目以上细度的精细胶粉,此法简称ATCG法,它的冷冻能耗成本仅为国际上通用的液氮法的十分之一,整个工艺过程不产生二次污染,为精细胶粉的制取开辟了一条新途径。 相似文献
96.
混合型表面活性剂液膜法处理含酚废水研究 总被引:25,自引:1,他引:24
研究了兰-113B=Span-80--煤油NaOH液膜体系处理苯酚废水的最佳操作工用于对高浓度含酚废水进行处理,实验结果表明,混合型表面活性剂各项指标均较好,除酚效率可达99%以上,对内相NaOH的最佳浓度的确定给出了估算方法。 相似文献
97.
以废钡渣为原料制取氯化钡的研究 总被引:6,自引:0,他引:6
本文研究了以直接耐晒黑G染料生产中的废钡渣为原料制取氯化钡的方法,氯化钡的得率达到废钡渣量的70.99%,产品质量达到一级品的标准。 相似文献
98.
对直径280mm、扩大直径500mm、外循环管直径65mm、总高2900mm的外循环型鼓泡式反应器,在气体空塔线速Ug为0.04-0.55m/s时,用静压差法和脉冲示踪法测定了不同部位的气含率Eg,Epg和循环液速率u1,并获得了它们的关联式:对反应段,Eg=0.4556U^0.3198g〔Ug/(Ug+U1)〕^0.7396;对反应器扩大段,Eug=0.9389U^0.4431ug;对循环管,E 相似文献
99.
Tadashi Hano Michiaki Matsumoto Takahisa Kawazu Takaaki Ohtake 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,62(1):60-63
The extraction equilibria of various di- and tripeptides with di-2-ethylhexylphosphoric acid (D2EHPA) were studied at low pH values. The complex extracted to organic phase consisted of one molecule of peptide and two molecules of D2EHPA dimer. The extraction constants of the peptides correlated well with the distribution coefficients of peptides between 1-octanol and water, which is a measure of hydrophobicity. The permeation rates of peptides through an emulsion liquid membrane were examined by using D2EHPA as a carrier, Span 80 as an emulsifier and kerosene as a diluent. The rates varied considerably with peptide type, depending upon the hydrophobicity. 相似文献
100.
通过金相、硬度、耐磨性等测试分析表明,在“603”液体渗碳基础上研制出的新型中温低氰液体碳氮共渗剂对薄片件进行薄层碳氮共渗.能完全满足技术要求,并且取得了良好经济和社会效益. 相似文献