我国农村生活污水厌氧生物处理技术及其应用进展

农村生活污水未经处理直接排入水体,容易造成水体富营养化,目前普遍应用的生物处理技术和生态处理技术。本文介绍厌氧生物处理技术基本原理,技术特点以及典型厌氧生物反应器在农村生活污水处理中应用,通过归纳总结我国农村生活污水厌氧生物处理技术研究应用进展对结构优化厌氧生物反应器强化农村污水处理效能提供借鉴。     

净化槽中生物滤床对家庭生活污水处理的水质影响

构建了适合于家庭分散式小型多功能一体化生活污水净化槽,通过逐步在净化槽内添加好氧、厌氧生物滤床,调查了净化槽各区生物滤床对净化槽净化效果的影响.试验结果表明,随着净化槽各区生物滤床的依次加入,出水水质更加稳定,抗冲击性能明显增强,处理效果尤为突出,当各区都加入填料且运行稳定时,出水BOD5平均值达到12.4 mg·L-1,优于国家一级排放标准.与不添加滤床相比,浊度去除率平均由70.8%提高到95.3%,BOD5去除率由74.7%提高到95.1%,充分显示了生物滤床在净化槽中的固液分离、生物吸附和生物降解的重要作用,是净化槽高效处理家庭生活污水不可缺少的关键技术.     

家庭生活污水分散处理净化槽的研究

开发了一种适合于农村生活污水分散处理的高效净化槽,使用平推流二段厌氧和全混流好氧一体化回流技术以及生物滤床技术,增加了各区中的生物茵含量,抑制了厌氧区的返混;采用部分回流,进一步提高了抗冲击性和出水水质.净化槽各区之间液体依靠静压差形成自流,降低了过程的能耗.试验结果表明,高效净化槽对于带有冲厕水的家庭生活污水具有很好的处理效果,出水COD＜60mg/L,BOD5＜20mg/L,NH3-N＜8mg/L,浊度＜SNTU,水质优于国家污水排放一级标准,具有很好的推广应用价值.     

农村污水现状及处理技术研究进展

介绍了农村污水状况,农村污水的危害及特点以及农村污水处理模式;阐述了人工湿地、生物生态滤池处理技术、厌氧好氧处理技术、稳定塘、水处理组合工艺、净化槽和土壤渗滤处理技术和污水一体化装置。认为人工湿地、稳定塘、污水处理一体化装置能适合大部分农村污水的处理,但需要进一步改良以提升污水的处理效率和稳定性,其他处理技术耦合效果还有待人们探究。     

净化槽不同曝气量对出水水质的影响

使用分散式家庭生活污水净化槽,调查了不同曝气量条件下净化槽各区对实际生活污水的净化效果,确定了最佳曝气量.试验证明,进水量为15L·d-1,经过两级厌氧处理后,COD、BOD5和浊度的去除率均在60%以上,当好氧区曝气量为3.28 m3·m3·h-1,溶解氧量为3.15 mg·L-1时,出水COD、BOD5、NH3-N和浊度分别为46、9.6、23.8mg·L-1和8.2 NTU;处理量为20 L·d-1,出水BOD5为12.4 mg·L-1,远低于国家要求的排放标准,具有较好的抗冲击性能.     

净化槽应用于农村生活污水处理可行性研究

针对我国农村偏远地区经济基础薄弱,人们环保意识淡薄,居民生活污水乱排放等特点,文章介绍了一种源于日本的一体化污水处理装置净化槽,对其工艺原理、处理流程、处理特点及其使用情况和相应的法律法规体系及今后在中国发展推广中遇到的问题和对策做了简要阐述。     

小城镇一体化污水处理站工程设计实例

云南省某小城镇污水来源主要为生活污水,具有水量较小、可生化性好、悬浮物浓度较高等特点,设计采用地埋式一体化PASG污水处理工艺,该工艺主要由两级构成,第一级为厌氧生化处理,第二级为综合生化处理。工程运行结果表明:出水CODCr、BOD5、SS、NH3-N、TN、TP的平均质量浓度分别为45、11.5、8.0、11.75、14.5、0.75 mg/L,出水水质能稳定达到GB 18918—2002《城镇污水处理厂污染物排放标准》中一级B排放标准的要求。介绍了污水处理工艺流程,给出了主要构筑物设计参数及投资运行成本。     

厌氧折板滤池处理农村污水研究

本研究以农村生活污水为研究对象,以新型厌氧生物滤池为技术核心,试验了厌氧折板滤池系统的启动方法和启动特点,重点研究了厌氧折板滤池技术对农村生活污水中CODCr、BOD5、氨氮、总磷等主要污染物的净化效果。     

城镇生活污水厌氧氨氧化处理的研究进展

厌氧氨氧化技术在城镇生活污水脱氮领域有巨大应用前景,在降低投资、低耗运行和污泥减量等方面具有重要优势,成为城镇生活污水处理的研究热点。本文综述了近年来厌氧氨氧化技术应用于城镇生活污水处理的最新研究进展,首先分析了有机物、污泥龄、溶解氧、温度及污泥截留等影响因素,认为厌氧氨氧化技术适宜处理城镇生活污水,并提出了相应技术挑战;探讨了侧流和主流厌氧氨氧化处理工艺在城镇生活污水处理中的优势、调控条件和现场应用效果。同时,根据现有研究结果,认为低氨氮浓度下保证稳定的亚硝态氮积累、低温条件下厌氧氨氧化稳定、厌氧氨氧化菌的快速富集以及主流工艺的推广应用等方面是城镇生活污水厌氧氨氧化处理大规模应用的瓶颈问题,并提出了厌氧氨氧化未来发展趋势。     

人工湿地系统处理生活污水工艺的改进

将单一的人工湿地工艺改进成厌氧-水平潜流人工湿地系统来处理生活污水,改进后工艺布局灵活,运行无能耗或低能耗,管理方便,抗冲击能力强,出水水质达到GB 18918-2002《城镇污水处理厂污染物排放标准》一级B标准,在南方丘陵地区对农村生活污水处理具有实用性和推广意义.     

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。