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1.
以焦化废水为研究对象,采用水热氧化技术研究废水处理的技术可行性,具有重大的理论和实际应用价值。在连续式反应器中,研究了实际焦化废水中主要污染物指标COD、NH3-N的降解行为。采用水热法处理焦化废水对COD去除率可达90%以上,当温度高于500 K时,COD浓度可降至300 mg/L以下,达到三级排放标准(GB 13456-1992)。停留时间是NH3-N彻底去除的主要因素。在停留时间达到12.46 min、温度为581 K、压力为15 MPa的亚临界条件下,NH3-N浓度可降至2.6 mg/L,达到一级排放标准。  相似文献   

2.
味精生产中离子交换废水的预处理技术研究   总被引:4,自引:0,他引:4  
采用电化学法、吹脱法和化学沉淀法对味精废水中离子交换废水的预处理进行了试验研究。结果表明:以铸铁屑为主的铁碳法,当HRT为2h时,pH可从1.97升至4.88,可大大减少后续中和吹氨所需石灰量,Fe-C还原对作COD、氨氮和提高可生化性无明显效果。pH中和至9.5-10,鼓气量在100m^3/h左右,水温55℃左右,经8h,可将原水NH3-N从12000mg/L左右降至4000mg/L左右,脱除率65%以上。磷酸氨镁法去除废水中NH4^ -N,在n(Mg^2+):n(PO4^3-):n(NH4^ -N)=1:1:1(物质的量比)时,随废水pH升高,NH4^ -N去除率逐步增大,pH为10时其去除率达到54%。  相似文献   

3.
焦化废水氨氮含量高,成分复杂,直接处理可能会对生物反应器造成影响。使用吹脱方法对焦化废水进行预处理,在pH值为10时可使氨氮降至120 mg/L,之后使用好氧的方法处理吹脱除氨后的焦化废水,经过驯化后焦化废水的出水COD可降至300 mg/L,加入葡萄糖进行共降解可以缩短好氧反应器启动时间。  相似文献   

4.
采用后继混凝沉淀的A/O工艺对含酚、氰的焦化废水进行了处理,运行结果表明:废水中酚质量浓度从287~681 mg/L降至1.0 mg/L以下,氰化物质量浓度从0.72~11.4 mg/L降至0.5 mg/L以下,完全达到了<污水综合排放标准>(GB 8978-1996)的二级排放标准;COD_(Cr)从3 879~6 378 mg/L降至116.1~184.2 mg/L.氨氮从145.6~200 mg/L降至11.64~25.26 mg/L.大多数时间达到排放标准.  相似文献   

5.
复合高铁酸盐在焦化废水脱色中的应用研究   总被引:7,自引:0,他引:7  
复合高铁酸盐用于处理经生化处理后不能达标的焦化废水的深度脱色处理,废水色度可从80降至25以下。复合高铁酸盐脱色的适宜条件为:复合高铁酸盐浓度1.7mg/L,溶液pH值3.5~7.0,反应时间30min,反应温度室温。  相似文献   

6.
霍莹  郑贝贝  杨勇  张莹  付连超 《广州化工》2014,(20):159-161,194
为了解决某厂高浓度氨氮废水达标排放问题,本文采用吹脱-折点加氯法对高浓度氨氮废水进行了处理试验研究。研究结果表明,在吹脱段pH值为11,温度35℃;氧化段pH值在7.5~8.5,次氯酸钠加入量(ω)为1%,氨氮的脱除率接近100%,可将废水中氨氮的浓度从4703 mg/L降至1 mg/L以下,远远低于GB8978-1996《污水综合排放标准》中的一级标准。  相似文献   

7.
焦化废水生物脱氮处理技术探讨与应用实例   总被引:1,自引:0,他引:1  
我国现有不同规模的焦化厂700多家,各类焦炉1 900多座,机焦年生产能力已达1·8×108t,在建装置能力81 000 kt/a。生产过程产生的大量焦化废水的处理一直是大家关注的问题。焦化废水含有大量有机物、高浓度氨、氰、SCN-等。除一些大型企业采用传统普通活性污泥法处理外,大多数企业没有废水处理系统。由于污水治理工艺落后或几乎未进行NH3-N处理,使排放的焦化废水COD不达标,氨氮严重超标,对环境造成很大的污染。《污水综合排放标准》(GB8978-1996)规定焦化废水二级排放标准为NH3-N含量≤25 mg/L,一级排放标准NH3-N含量≤15 mg/L,而一…  相似文献   

8.
高效吹脱法+折点氯化法处理高氨氮废水   总被引:3,自引:0,他引:3  
黄军  邵永康 《水处理技术》2013,39(8):131-133
以某化工生产企业废水为例,介绍高效吹脱法+折点氯化处理高氨氮废水的工程实例。该工程设计规模为3000m3/d,即125m3/h,进水NH3-N质量浓度高达1200mg/L。实践表明,采用该工艺处理高氨氮废水效果很好,出水NH3-N质量浓度小于15mg/L,可达污水综合排放标准(GB8978-1996)一级排放标准。  相似文献   

9.
A_1-A_2-O-M工艺处理焦化废水的实验研究   总被引:1,自引:0,他引:1  
采用厌氧-缺氧-好氧-复合(A1-A2-O-M)工艺处理焦化废水,考察了外加碳源和碱源对焦化废水COD和NH4+-N脱除效果的影响。试验结果表明:外加甲醇和碳酸氢钠对焦化废水的硝化和反硝化效果影响很小;不外加碳源和碱源时,焦化废水经处理后出水的COD和NH4+-N平均质量浓度分别为125.0mg/L和1.12mg/L,分别达到《污水综合排放标准》(GB8978-1996)中的二级标准和一级标准。  相似文献   

10.
晋建民 《中氮肥》2002,(2):35-37
近几年我国焦化污水治理取得较大进展,新建焦化企业大都采用A/O工艺处理焦化废水,效果较好,废水中的COD、NH3-N达到GB8978-1996规定的要求,而且运行管理也取得了相当成熟的经验。我公司新建焦化二厂的污水处理装置也选用了A/O工艺,设计处理能力100m^3/h。该装置于2000年12月建成,投运后经过近一年的运行实践,生化出水达到COD≤200mg/L,NH3N≤25mg/L。  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   

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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   

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