磁粉投加量对SBR工艺污水处理效果的影响

针对传统SBR工艺污泥絮体结构松散,沉降速率低等问题,实验采用磁化技术处理生活污水。考察磁粉(微米Fe_3O_4)对生活污水处理效果的影响,确定最佳磁粉投加量。结果表明,磁化污泥处理污水的效果要优于普通活性污泥,最佳磁粉投加量为0.5~0.7 g/L,综合考虑经济和处理效果两方面因素,选择磁粉投加量0.5 g/L较为合适。此时平均出水COD、氨氮、总氮和总磷的平均去除率分别为95.30%、91.48%、70.83%和92.80%,平均出水COD为16.60 mg/L,平均出水氨氮、总氮和总磷浓度分别2.74、10.01、0.53 mg/L,达到城镇污水处理厂污染物排放标准(GB1891-2002)一级标准。     

固定化生物硅藻土强化CAST工艺处理含盐污水研究

采用9%聚乙烯醇+0.5%海藻酸钠包埋耐盐菌群的固定化生物硅藻土小球投加到循环式活性污泥(CAST)反应器中,对比传统CAST工艺和投加固定化小球的CAST工艺对含盐污水COD和氨氮的去除效果,考察固定化生物硅藻土小球强化CAST工艺处理含盐污水性能。试验结果表明:在相同运行条件下,投加固定化生物硅藻土小球的CAST工艺出水COD、氨氮去除率基本维持在88%和90%以上,与传统CAST工艺相比分别提高了15%和10%。同时,向CAST工艺添加固定化生物硅藻土有助于维持反应器中微生物浓度稳定,提高出水水质及其稳定性。     

包埋固定化硝化菌去除氨氮的试验研究

采用包埋固定化硝化菌颗粒投加率为15%的流化床反应器考察该包埋固定化菌在不同HRT条件下的驯化情况以及DO含量对氨氮去除效果的影响,并使用驯化后的包埋菌考察燃料乙醇生产废水中氨氮的处理效果.结果表明,在平均水温24.8℃、DO的质量浓度为5 mg·L-1左右时,该包埋菌对燃料乙醇生产废水具有较强的除氮能力,出水氨氮的质量浓度<15mg·L-1,能够达到GB 18918-2002中对氨氮的排放要求.     

复合絮凝剂-SBR工艺处理市政污水中试研究

采用复合絮凝剂-序批式活性污泥法(SBR)工艺对北京某污水厂初沉池出水进行中试处理,研究了该工艺的出水水质和污泥性能。结果表明,在水处理量为0.75 m~3/h、复合絮凝剂投加量为20μL/L的情况下,出水COD和TP、NH_4~+-N、TN的质量浓度平均分别为20.5 mg/L和0.3、0.5、14 mg/L,均可达到GB 18918-2002一级A标准。在长期投加复合絮凝剂的条件下,污泥沉降性能提升明显,胞外聚合物凝聚性变强,整体性能已十分接近好氧颗粒污泥。复合絮凝剂-SBR工艺继承在好氧颗粒污泥技术大部分优点的同时,更能保证污泥颗粒和出水水质稳定,可用于污水处理厂提标改造。     

高浓度氨氮对活性污泥性能的影响

采用2个SBR反应器RUN1和RUN2在氨氮质量浓度分别为50、350 mg/L的条件下驯化污泥,考察氨氮浓度对污泥活性的影响;并在氨氮质量浓度分别为59、232、368、604和1 152 mg/L的条件下对2个反应器中的驯化污泥进行氨氮适应性试验。结果表明:在较高的氨氮浓度条件下,有机物降解菌对CODCr降解率下降约47%,硝化菌对氨氮的去除率下降约55%,脱氢酶活性下降约56.6%,显示出高浓度氨氮对有机物降解菌和硝化菌的活性都具有一定的抑制作用;当进水氨氮质量浓度从59 mg/L升至1 152 mg/L时,RUN1和RUN2中污泥对CODCr的去除率分别由89.2%和91.9%下降为40.5%和67.6%,对氨氮的去除率则分别由99.8%和99.9%下降为17.1%和22.2%,说明经高浓度氨氮驯化的污泥,其有机物降解菌和硝化菌都显示出对高浓度氨氮更好的适应性。     

填料-循环活性污泥系统处理酒精废水试验研究

结合某玉米酒精厂现有循环活性污泥系统(CASS)的不足,提出了利用填料强化该工艺的污染物削减能力的方法,以正交试验的方法,研究了MLSS含量、曝气时间、填料投加量和DO含量4个运行参数对填料-CASS的影响。结果表明,4个因素对COD去除率影响主次顺序为DO的质量浓度>填料投加率>MLSS的质量浓度>曝气时间,优化参数组合为:MLSS的质量浓度4.6 g/L、填料投加率为30%、曝气时间6 h、DO的质量浓度6.5 mg/L,在此条件下,当进水COD和NH3-N的质量浓度分别为540.1～862.47 mg/L和17.61～31.76 mg/L时,出水COD为和NH3-N的质量浓度分别为62.87～90.76 mg/L和0.69～1.01 mg/L,均能满足GB 27631-2011的排放要求;平均去除率分别为89.21%和96.22%。     

活性污泥膜分离技术在畜禽废水处理中的应用

畜禽废水有机物和氨氮浓度高,采用活性污泥膜分离技术处理畜禽废水,在进水CODCr6783～8202mg/L,BOD54260mg/L,SS6960mg/L,NH3-N392～483mg/L的条件下,出水CODCr<100mg/L,BOD5<20mg/L,SS<70mg/L,NH3-N<15mg/L。     

以海绵填料为生物载体的MBio一体化生物反应器的快速启动研究

以海绵填料为生物载体的MBio一体化生物反应器的快速启动为研究对象,通过补充活性污泥菌液、投加硝化菌剂,间歇进水逐级提高水量的方法进行了14天的调试。结果表明在进水水质指标CODCr=20～60 mg/L、NH3-N=4～10 mg/L,水温18℃的低营养物质、低温条件下,实现出水的快速达标,平均出水浓度CODCr小于20 mg/L,NH3-N小于2 mg/L,优于准Ⅳ类水的部分水质指标。     

EM菌活性污泥系统对皂素废水的深度处理试验

在活性污泥系统中利用EM菌液通过SBR反应器对经过一次生化处理的皂素生产废水进行深度处理研究,结果表明:在进水COD的质量浓度为3 000～3 250 mg/L,EM复壮液用量为进水量的0.7%,活性污泥液用量为EM复壮液的2倍,投加周期为9 d,系统一次曝气时间为16 h时,COD的去除率可达74.4%,最终出水COD的质量浓度基本稳定在800 mg/L左右,可达国家污水综合排放三级标准。     

硝化菌包埋载体中试系统启动与稳定运行

为了验证硝化菌包埋载体技术的可行性和可靠性并获得到工程应用的参数,针对该技术进行了中试,考察了硝化菌包埋载体系统的活化启动特性和稳定运行情况及主要影响条件。结果表明,在常温条件下(20~25℃),接种普通好氧活性污泥,以包埋硝化菌载体为核心的处理系统活化启动时间不超过15d;稳定运行阶段,包埋硝化菌载体系统在低污泥含量条件、投加体积分数7.95%和负荷逐渐提高的情况下处理城镇生活污水可使出水氨氮的质量浓度平均达2 mg/L左右,去除率达95%以上,且该系统最终所需气水体积比只有7:1。     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2007～2008年世界塑料工业进展

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.     

2005～2006年国外塑料工业进展

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。