首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
粉煤灰吸附含氟废水试验研究   总被引:1,自引:0,他引:1  
选用粉煤灰作为吸附剂,进行了粉煤灰处理含氟废水的试验研究,分析了初始浓度,pH值,时间以及吸附剂投加量对除氟的影响。试验表明:粉煤灰具有一定的除氟能力,能使含氟260mg/L的废水除氟率达68.2%;粉煤灰对酸性含氟废水具有一定的中和能力;粉煤灰除氟最佳反应条件为:室温下,水灰比为20:1,pH值为3,搅拌时间为60m in。采用该法原料价廉,容易得到,操作简单,同时实现粉煤灰的综合利用和含氟废水的处理。  相似文献   

2.
改性海泡石处理含氟废水的研究   总被引:1,自引:0,他引:1  
刘祺 《中国陶瓷》2008,44(6):52-54
提出了对海泡石进行改性和活化处理的有效方法,探讨了改性海泡石用于处理含氟废水的各项影响因素。结果表明:经改性活化后的海泡石对水溶液中氟的去除效果明显优于未经改性活化的海泡石。处理的最佳条件为:室温25℃,固液之比为1:500,pH为6.0,处理时间为30分钟。在此条件下处理含氟废水,对模拟水样除氟率可达到86%,除氟后的水质完全达到国家排放标准,效果良好。  相似文献   

3.
强力霉素废水中氟的处理研究   总被引:1,自引:0,他引:1  
根据强力霉素含氟废水的特点,采用石灰-粉煤灰两段净化工艺处理其中的氟,并对影响处理效果的主要因素进行了试验研究.结果表明,一段处理最佳条件:m(Ca)∶m(F)=2、反应时间40min;二段处理最佳条件:粉煤灰粒径小于200目,灰水比为1∶10,振荡吸附时间为200min,pH4~8;处理后的废水中氟质量浓度<10 mg/L,达到了GB 8978-1996《污水综合排放标准》中的一级标准.该方法工艺简单、操作方便、成本低廉.处理废水后的含氟灰渣烧制成砖块,不会对环境造成二次污染,并达到了以废治废的目的.  相似文献   

4.
粉煤灰去除抗生素含氟废水的实验研究   总被引:1,自引:0,他引:1  
根据强力霉素抗生素含氟废水的特点,采用石灰-粉煤灰两段净化工艺处理其中的氟,并对影响处理效果的主要因素进行了实验研究.结果表明,一段处理最佳条件:Ca/F重量比为2、反应时间40min;二段处理最佳条件为:粉煤灰粒径小于74μm(200目)、灰水比为1∶10、振荡吸附时间为200min、pH值=4~8;处理后的废水中氟浓度达到了GB8978-96<污水综合排放标准>中的一级标准.  相似文献   

5.
针对石灰-粉煤灰联用处理高浓度含氟废水工艺的研究。研究结果表明,石灰一级处理L25(56)正交实验确定的最佳条件为温度为10℃、石灰投加量0.15 g、反应时间为30 min、PAM(浓度1%)加入量为0.1 mL、pH为7.0,该条件对200~1000 mg/L浓度范围的含氟废水具有较好的适用性;粉煤灰二级处理L27(313)正交实验确定的最佳条件为温度为35℃、粉煤灰加入量6.0 g、吸附时间为90 min、pH为5.5;采用石灰-粉煤灰联用处理1000 mg/L含氟废水,出水氟离子浓度可低至4 mg/L。工艺材料价廉易得、工艺简单、对含氟废水浓度适应性较宽。  相似文献   

6.
用改性粉煤灰处理含氟废水的试验   总被引:6,自引:0,他引:6  
通过实验探讨了改性粉煤灰处理含氟废水的影响因素。实验结果表明:经Ca(OH)2溶液改性的粉煤灰的除氟性能与改性试剂Ca(OH)2溶液的浓度、吸附时间、废水氟离子初始浓度、废水pH值、反应温度等因素有关。将氟离子浓度为267.0mg/L的含氟废水的pH调至3.5后,按每升废水中加入经过5%的Ca(OH)2溶液改性烘干的粉煤灰0.05g,在室温下振荡1h,F-去除率可达98.0%。最后对改性粉煤灰处理含氟废水的机理作了初步分析。  相似文献   

7.
《煤化工》2019,(5)
采用除氟剂1和除氟剂2分段添加的工艺处理航天炉煤气化系统的高氟废水。考察了除氟剂1的组成比例、灰水pH、除氟剂2的用量对高氟废水处理的影响。实验结果表明:随着除氟剂1中电石渣和粉煤灰复配比例的不同,废水中氟离子的处理效果明显不同,7∶3为最佳复配比;随着pH值的增加,废水中氟离子含量先降低再升高,在pH为10.5左右时,氟离子含量最低;一段除氟与二段除氟除氟剂2的添加按照2∶1的体积用量进行效果最好,废水中的氟离子质量分数可降至1×10~(-6)。  相似文献   

8.
对含氟废水和含氟废渣中氟的去除,采用磷化铝处置残渣进行除氟实验研究.结果表明,含氟废水在pH为8~10,磷化铝处置残渣加入量为w=10%,0.1%PAM加入w=1%的条件下,废水中氟从1250 mg/L降至7.5 mg/L,除氟率达99.4%.处理后的含氟废水中氟低于GB8978-1996《污水综合排放标准》中氟化物(...  相似文献   

9.
采用成本较低的粉煤灰和皂化母液为钙源处理含氟废水,结果表明:粉煤灰和皂化母液均可将4 250~29 419 mg/L的含氟废水中的氟离子浓度降低至11~60 mg/L,达到了以废治废的目的。  相似文献   

10.
混凝-吸附法处理高浓度含氟磷废水的研究   总被引:8,自引:0,他引:8  
李亚峰  徐文涛 《当代化工》2001,30(4):193-195
对采用石灰和粉煤灰处理高浓度含氟含磷化工废水的方法进行了实验研究,考察了石灰用量,搅拌反应时间,接触时间等因素的影响,同时确定了粉煤灰的吸附容量,实验结果表明,采用石灰混凝沉淀-粉煤灰过滤工艺处理高浓度含氟含磷化工废水,处理后氟,磷及其他各项指标均达到国家排放标准。  相似文献   

11.
12.
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.
14.
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   

15.
16.
17.
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   

18.
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   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号