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1.
采用分段式进水一体化工艺处理校园生活污水,考察了不同影响因素对除磷效率的影响。试验结果表明:在厌氧区和缺氧区进水流量比为3∶1时,总磷去除率最高,平均去除率达到了93%以上;在好氧区DO的质量浓度约为2.0 mg/L时,总磷去除率最高,平均去除率达到了91%以上;在HRT为8 h时,总磷去除率最高,平均去除率达到了93%左右;正交试验结果表明影响TP去除率的因素优先顺序为DO、进水流量比、 HRT,最佳组合工艺参数为厌氧区和缺氧区进水流量比为3∶1, DO的质量浓度为2.0 mg/L, HRT为8 h。  相似文献   

2.
采用铁炭微电解法对羧甲基纤维素废水进行预处理试验,研究了初始pH值、曝气、停留时间等关键因素对COD去除的影响。结果表明当进水COD的质量浓度为16000mg/L,进水初始pH值为3.5,停留时间75min,铁炭体积比为1∶1,曝气量为5L/min,此条件下COD去除率为35.14%,试验达到了预期目的。  相似文献   

3.
超声/微电解协同处理含磷废水   总被引:1,自引:0,他引:1  
试验采用超声/微电解联合体系处理含磷废水。以含磷废水为目标污染物,主要考察了温度、废水的浓度、反应时间、废水的初始pH、铁炭比和铁水比对废水中总磷去除效果的影响。在此基础上,挑选主要影响因素设计正交试验(L9(34)),得出反应条件的最优组合;超声辅助进行单因素对比试验,论证超声辅助能否大幅度提高除磷效果。结果表明,最佳的工艺条件为初始pH=4.00,反应时间60 min,铁炭体积比2:1,铁水体积比1/10,且在最佳条件下,总磷的去除率为77.3%,超声波技术联用后,总磷的去除率可高达92%以上。对比试验结果和动力学研究表明,超声波对微电解技术有良好的协同作用,协同因子E=2.25,且降解过程符合表观1级动力学规律。  相似文献   

4.
铁炭微电解法预处理制药废水的研究   总被引:8,自引:0,他引:8  
史敬伟  杨晓东 《辽宁化工》2006,35(4):211-213
依据微电解法的基本原理,采用铁炭对制药利福平废水进行预处理研究。通过实验确定了进水时的pH值、水力停留时间、铁炭质量比以及填料粒径大小4个影响因素。即用微电解法预处理制药废水的最佳工艺条件及在该条件下有机废水的处理结果分别为:预处理利福平废水,进水pH=2,铁屑粒度为24目,铁炭比为20∶1,废水在微电解柱中的停留时间为120 min;水样COD去除率达到53.5%,色度去除率达到90.00%。  相似文献   

5.
选用铁炭法处理水体中的总磷,研究该技术的可行性及其特点。进行L_9(3~4)四因素三水平正交优化试验,结果表明,铁炭法除磷的影响因素主次关系依次为铁炭总量、振荡的转速、反应时间、铁炭比。在最优组合工艺条件下,即铁炭比为3∶2,铁炭总量为20 g/L,转速为120 r/min,反应时间为75 min,对浓度为1.0 mg/L的含磷污水去除率达到98%,出水总磷浓度为0.02 mg/L,达到《地表水环境质量标准》(GB3838-2002)Ⅰ类水质。动力学分析表明,铁炭法除磷符合零级反应动力学规律。该技术在实验室环境下取得了较好的处理效果,对研究水体中总磷的去除方法有一定参考价值。  相似文献   

6.
采用铁炭微电解-Fenton氧化法对含喹吖啶酮颜料中间体有机废水进行预处理。得到微电解的最佳条件是:pH值为5、铁水体积比为0.375、铁炭体积比为1、反应停留时间为60 min;且这4因素的影响顺序是pH值>铁屑投加量>铁炭体积比>停留时间。Fenton氧化法的最佳条件是:pH值为4~7、反应时间为50 min、FeSO4和H2O2投加量分别为300 mg/L和2.5 mL/L。试验结果表明,将这两种方法联合对含喹吖啶酮颜料中间体有机废水的处理效果十分明显,在最佳试验条件下,当进水COD质量浓度为16 800 mg/L,色度为20 000倍时,COD的总去除率达到94%以上,出水色度小于40倍,为后续处理创造了有利条件。  相似文献   

7.
铁屑微电解——中和沉淀预处理颜料中间体废水   总被引:3,自引:0,他引:3  
采用铁屑微电解--中和沉淀法对颜料中间体有机废水进行预处理,对各种因素进行了单因素试验和正交试验.试验结果表明,在进水pH为5,铁水比为0.375,铁炭比(V/V)为1,停留时间为60 min时,COD去除率和脱色率都达到80%以上.  相似文献   

8.
微电解-混凝预处理环己酮废水   总被引:1,自引:0,他引:1  
研究了用铁炭微电解.混凝工艺预处理高浓度环己酮废水,通过实验确定了铁炭质量比、进水pH值、水力停留时间及曝气时间4个影响因素的最佳条件分别为:铁炭质量比为1:2,环己酮废水进水pH为2~3,停留时间为4h且有曝气条件下,COD去除率达到55.35%,废水的可生化性得到提高。  相似文献   

9.
微电解-Fenton试剂氧化处理硬丁腈橡胶废水   总被引:3,自引:0,他引:3  
采用铁炭微电解-Fenton试剂法联合处理硬丁腈橡胶装置的拉开粉(BX)废水,试验了各种条件对废水中的COD和BX去除率的影响.结果表明,铁炭微电解的最佳工艺条件是:进水pH为3~4、铁炭质量比为1∶1、气水体积比为10:1、停留时间为30 min,对废水的COD和BX去除率分别达到51%和50%以上;以微电解反应出水作为后续Fenton试剂反应器的进水,当质量分数10%的FeSO4溶液的投加量为3.75 mL·L-1,pH=3.0±0.15、停留时间为60 min时,质量分数27.5%的H2O2溶液投加量为7.5 mL·L-1时效果最好,COD和BX去除率分别达到80%和87%以上.  相似文献   

10.
李咏峰  李文辉  钟理 《广州化工》2010,38(8):220-221,226
通过对佛山市某污水处理厂三槽式氧化沟总氮和总磷去除率的数据分析,找出进水浓度,温度、湿度和pH与总氮、总磷去除率的之间关系,获得了三槽式氧化沟脱氮除磷的最佳运行条件。实验结果表明,在进水污染物浓度较高的条件下,温度在20℃~22℃之间,pH范围在7.6~7.8的脱氮除磷的效果最为理想,湿度对氮、磷去除率没有影响。  相似文献   

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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   

13.
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

14.
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  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   

19.
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   

20.
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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