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1.
为降低磷酸二铵装置排放尾气的尘含量,在原有洗涤系统的基础上对尾气系统进行改造。对含氨的尾气,采用25 m~3电除雾器进行除尘;对不含氨的尾气,增加布袋除尘器除尘。改造后,ρ(尘)由改造前的200 mg/m~3下降到30 mg/m~3,装置氨收率增加了0.5%,实现尾气达标排放。  相似文献   

2.
兖矿国泰化工有限公司300 kt/a甲醇系统采用四喷嘴新型气化炉制气,NHD脱硫,脱硫富液再生后产生的H2S气体经克劳斯硫回收装置生产硫磺产品.硫回收装置的硫回收系统运行情况较好,但尾气加氢反应系统、尾气洗涤系统等运行不稳定(尾气加氢炉经常出现积炭、炉壁烧穿等情况,尾气焚烧炉检修频繁),导致排放尾气中SO2含量高(1300~2600 mg/m3),不能够实现达标排放,环保压力较大.为此,公司通过对改造硫回收装置尾气系统与新建尾气氨法脱硫装置进行比选,决定新建氨法脱硫装置以脱除硫回收尾气中的SO2,实现硫回收尾气的达标排放.  相似文献   

3.
文慧 《磷肥与复肥》2015,30(6):33-34
阐述甘肃瓮福化工有限责任公司从优化改造湿法磷酸装置氟吸收工艺入手,通过规范装置内氟的控制和回收,实现了对反应、过滤系统和磷酸浓缩系统尾气中氟含量的有效回收,使洗涤后排到大气中的反应尾气氟质量浓度不超过2.35 mg/m~3,尾气中氟的回收率达99.88%。氟回收率的提高,使氟硅酸产量由每月400 t提高至每月550 t,实现了湿法磷酸装置的经济、环保运行。  相似文献   

4.
针对甘肃瓮福公司的磷铵装置扩能改造后尾气洗涤系统严重超负荷、氨逸出率高等问题,对尾气洗涤系统进行了改造。通过新增干燥尾气洗涤系统,将造粒系统尾洗和干燥系统尾洗分开设置,氨耗由245 kg/t下降至217 kg/t,氨排放量由1.14kg/h下降为0.25kg/h,粉尘排放质量浓度由87.3 mg/m3下降为62.5 mg/m3。  相似文献   

5.
六国化工磷铵扩能改造后,出现尾气尘含量超标,分析原因是旋风除尘效率及旋流板洗涤效率低.通过改造旋风除尘器下料装置,减小旋流板的仰角,改善洗涤液性能后,尾气尘含量小于国标值(150mg/m3),做到达标排放.  相似文献   

6.
荣辉  张迅 《磷肥与复肥》2008,23(4):44-45
对传统中和尾气吸收装置进行改造,利用磷酸吸收中和尾气中的气氨,循环吸收液重新返回混酸系统使用。通过改造,排放中和尾气中的氨含量由175 mg/m3下降至67mg/m3,使尾气排放达标。  相似文献   

7.
以氨水作为吸收剂,采用逆流洗涤及氟硅料浆强制过滤技术,依次经二氟洗涤塔、一氟洗涤塔及文丘里洗涤器吸收湿法磷酸含氟生产尾气,研究得出,最佳尾气氨洗法工艺为二氟洗涤液p H 7.5,温度45℃,停留时间35 min,喷淋密度6.5 m3/(m2·h)及空塔气速4.0 m/s,该条件下,系统尾气氟化物质量浓度为6.31 mg/m3,一氟洗涤塔离心滤液氟化物质量分数为11.33%,联产无水氟化氢及白炭黑转化直接经济效益1 102.76万元/a。  相似文献   

8.
过磷酸钙由50kt/a扩能达200kt/a。介绍氟吸收系统改造的流程、设备及改造后的运行情况。喷淋式吸收塔代替拨水轮,增加吸收液的硅胶分离装置和冷却装置,极大地提高了氟吸收率,尾气达标排放并可制取高浓度氟硅酸液作为商品出售。  相似文献   

9.
介绍青海云天化国际化肥有限公司磷酸二铵装置尾气洗涤系统存在的问题和改造前后的尾洗工艺流程。对比分析改造前后的尾气检测数据可知,改造后尾气中氨、颗粒物质量浓度分别从115.0、804.0 mg/m3降至48.9、147.7 mg/m3,达到了GB16297—1996要求,且回收液氨88.34 t、粉尘889.9 t,效果显著。  相似文献   

10.
湖北大峪口化工有限责任公司磷酸一铵装置采用料浆法工艺生产,该工艺通常采用一级酸洗法处理造粒干燥尾气,氟逸出率较大。经技改采用一级酸洗、二级水洗两级复合洗涤法,并对工艺参数进行调整,改造后尾气中的ρ(F)从90.7 mg/m3降为3.2 mg/m3,满足国家标准要求。  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   

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15.
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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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   

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