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1.
采用聚丙烯中空纤维膜接触器,分别用去离子水、单乙醇胺(MEA)及N-甲基二乙醇胺(MDEA)水溶液作为吸收剂,对模拟烟气中的CO2分离进行了试验研究.考察了气体流速、入口气体中CO2体积分数、吸收剂流速、吸收剂浓度以及吸收剂种类等因素对CO2脱除率和总传质速率的影响.实验结果显示:3种吸收剂分离CO2的效率由大到小依次为MEA、MDEA、去离子水;CO2的脱除率和传质通量随吸收剂浓度、流速的提高均增加;CO2的脱除率随气体流速和CO2在入口气体中体积分数的增大而减小,而传质速率却随之增加.系统长时间运行后发现存在膜孔润湿现象,进而影响膜的传质性能.因此,吸收剂浓度须在传质和长时间运行性能之间进行权衡.  相似文献   

2.
将无机盐硼酸钾作为活化剂添加于甘氨酸盐溶液中,形成活化复合吸收剂;采用膜接触器装置,评价和比较了甘氨酸盐和活化复合吸收剂捕集CO2的性能。研究了活化剂浓度、液相流量和操作温度等因素对总体积传质系数、传质通量和捕集率的影响。结果表明:活化复合吸收剂对CO2的捕集产生明显的影响,活化复合吸收剂的总体积传质系数高于甘氨酸盐吸收剂;活化剂浓度对传质通量的影响表明,少量活化剂的作用远比多量的活化作用大;活化复合吸收剂的捕集率远大于甘氨酸盐吸收剂;膜接触器流体力学状态的改变,能够改善膜接触器传质性能,增大传质通量,但增大的程度有限;操作温度对膜吸收传质通量影响较大,温度越高,传质通量越高。  相似文献   

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中空纤维致密膜基吸收法在CO2脱除中的应用   总被引:1,自引:0,他引:1  
以商业φ200聚酰亚胺中空纤维致密膜大组件为接触器,淡水和海水为吸收剂,进行了CO2/N2混合气中CO2的脱除实验。考察了气液相压力和流量对CO2脱除率和过程总传质系数的影响。结果显示,液相压力对膜接触器的影响不大,而加大液/气相流量比可以提高CO2的脱除效率,通过控制操作条件可使膜接触器的CO2脱除率在70%以上。实验过程中,气液两相压力可在较宽范围内独立操作,且无鼓泡和漏液现象发生。研究表明中空纤维致密膜基接触器在CO2气体分离领域具有很好的应用潜力和前景。  相似文献   

4.
研究了气体膜分离与溶剂吸收相结合的分离技术.以NaOH水溶液为吸收剂,在中空纤维膜组件中实现二氧化硫气体的选择性吸收.研究了在三种不同结构的疏水性聚丙烯中空纤维膜组件中,吸收剂浓度、液速、气速、气液两相在膜组件内的流程、膜结构等对分离过程的影响;根据膜结构的实际参数确定了多孔膜的曲率因子,总传质系数的计算值与实验值相符.  相似文献   

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中空纤维膜基吸收法脱除空气中二氧化碳的研究   总被引:16,自引:4,他引:16  
以醇胺类水溶液作为吸收剂,采用聚丙烯中空纤维膜组件进行膜基气体吸收脱除空气中CO2的研究。实验 结果表明,在吸收液浓度为2.0mol·L-1,气速小于0.30m·s-1,吸收液流速小于0.01m·s-1的条件下,其吸收CO2的 总传质系数约为0.03~0.06mol·m-2·min-1·(mol·L-1)-1。研究建立了估算吸收总传质系数的数学模型,模型计算 曲线与实验数据曲线基本一致,可用于膜基气体吸收法脱除CO2过程的放大设计。  相似文献   

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以浓海水为含溴原料液,NaOH溶液为吸收剂,考察了用聚丙烯(PP)、聚偏氟乙烯(PVDF)和聚四氟乙烯(PTFE)3种材料制作的微孔疏水中空纤维气态膜组件从浓海水中提溴的性能和使用寿命。实验结果表明PTFE中空纤维膜具有更高的传质系数和更强的耐溴氧化能力,更适合用于浓海水提溴。进而考察了各种操作条件对PTFE气态膜组件传质系数K和提溴率η的影响以及该组件的长期操作稳定性。实验结果表明:K随温度增加而增大,随料液中NaCl含量的增大而略有减小,料液流速和含溴量、吸收液的流速和吸收剂浓度对传质系数影响不大。PTFE膜组件在连续运行的3个月内表现了良好的操作稳定性,为PTFE中空纤维气态膜法提溴工艺的工业化应用提供了技术基础。  相似文献   

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膜基-氨基酸盐及其复合溶液吸收CO_2的性能   总被引:5,自引:3,他引:2  
选择了氨基乙酸(GLY)和氨基丙酸(ALA)的盐溶液作为CO2吸收剂,将高效活化剂哌嗪(PZ)添加于GLY形成新型氨基酸基复合溶液,采用膜接触器-再生循环装置,研究了液速、吸收剂浓度等因素对总传质系数和脱除率的影响,评价和比较了GLY和ALA及其复合溶液的吸收性能。结果表明:GLY的传质推动力大于ALA,GLY的总传质系数和脱除率大于ALA;在吸收剂浓度对总传质系数的影响程度上,GLY大于ALA;复合溶液的吸收性能明显优于单一的氨基酸盐溶液,少量的PZ能显著地增强传质效率。  相似文献   

8.
PVDF中空纤维膜接触器分离烟气CO2   总被引:1,自引:0,他引:1       下载免费PDF全文
以水(H2O)、氢氧化钠(NaOH)、氨基乙酸钾(GLY)、氨基乙酸钾-哌嗪(GLY-PZ)水溶液为吸收剂,研究了疏水性聚偏氟乙烯(PVDF)中空纤维膜接触器分离CO2/N2模拟烟气中CO2的技术,具体考察了流动方式、气液流率、吸收液浓度和温度、原料气CO2浓度、填充密度等对膜接触器吸收效率的影响。结果表明,气液逆流的腔流程模式具有较高的分离效率。不同吸收剂的分离性能为:NaOH > GLY-PZ > GLY > H2O。温度对各种吸收剂的影响随其种类不同而有所差异。膜接触器对烟气CO2的分离效率随填充密度、吸收液浓度和流率的提高而增大,随气体流率及其中CO2浓度的增大而减小。  相似文献   

9.
孔隙率对膜吸收过程影响的实验研究   总被引:1,自引:0,他引:1  
采用纯CO2-去离子水和0.1 mol·L-1NaOH溶液为实验体系,选用8种具有不同微观结构的板式膜,研究了膜厚度、孔隙率,微孔形态等对膜吸收过程中传质性能的影响.结果表明,不同的微孔形态(拉伸孔、柱状孔)以及所用膜的厚度对膜吸收过程传质性能的影响较小,在吸收速率较快时孔隙率会影响膜吸收过程的传质性能.同时,还对溶质在液相侧表面的传质行为进行了探讨,结果表明膜孔隙率对膜吸收过程的传质性能的影响与流动状态、反应体系、微孔间距等多因素有关.  相似文献   

10.
酸性气体膜吸收过程中浓差极化   总被引:6,自引:0,他引:6  
用聚丙烯中空纤维膜吸收器,针对酸性气体膜吸收传质过程,根据浓差极化时存在局部高浓度区的特点,分别进行了SO2/空气混合气和CO2/空气混合气中酸性气体的选择性吸收实验. 实验测定了SO2和CO2两种不同酸性气体在不同浓度吸收液及不同液速下的总传质系数,比较了两种酸性气体在液相侧的传质特性,根据两组份间化学反应机理的不同,分析了浓差极化对膜吸收过程的影响.  相似文献   

11.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

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收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

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Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.  相似文献   

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