城市污水处理厂A~2/O运行问题分析及解决方法

针对浙江省城镇污水处理厂尾水排放标准的升级要求,以浙江省某污水处理厂为改造对象,在原系统基础上增设"投加碳源"、"絮凝过滤"、"消毒"等处理工艺,完成对该污水处理厂的改造工程,并对改造后的污水处理厂进出水中各污染物浓度进行了为期1个月的监测。监测结果表明,在原系统基础上增设"投加碳源"、"絮凝过滤"、"消毒"等处理工艺,能显著提高该污水处理系统对生活污水中COD、BOD5、NH3-N、TN、TP及SS的去除能力,上述污染物的出水浓度均低于城镇污水处理厂污染物排放标准(GB 18918-2002)一级A标准,有效解决了原有A2/O工艺的运行问题,实现了城镇污水处理厂的长期稳定达标排放。     

石化污水预处理改造中气浮的应用

根据石化污水水质波动大,污水中含有油和悬浮物的特点,结合污水改造工程,重点对污水预处理系统进行了技术改造,将原部分调节池改造为涡凹气浮,从而形成以混合反应、气浮、匀质调节为主体的预处理工艺。改造后气浮系统的运行结果表明,在进水量为2500m3/h,聚合氯化铝投加量为16mg/L,聚丙烯酰胺投加量为1mg/L的条件下,气浮CODCr去除率为41%,SS去除率为69%,石油类去除率为68%,达到了预期效果。     

基于总氮达标的河南省某污水处理厂提标改造工艺研究

总氮达标排放是目前城市污水处理厂提标改造的重点。在对河南省某污水处理厂进水水质调查分析的基础上,针对原有工艺存在总氮超标的风险,进行"增加碳源精准投加系统并将生物池运行工艺调整为倒置A2O工艺"的提标改造,提高了污水中总氮的去除效率,确保污水处理厂出水稳定达标排放。结果表明:自2018年5月调试运行以来,出水水质稳定达到贾鲁河流域水污染物排放标准(DB 41/908-2014)。     

低温胁迫下海藻糖强化厌氧氨氧化污泥活性研究

利用升流式厌氧污泥床(UASB)反应器,采用实验室已经驯化好的厌氧氨氧化颗粒污泥,在低温(12℃)条件下进行连续流培养,研究低温胁迫条件下不同的海藻糖投加量对UASB反应器脱氮效能和厌氧氨氧化污泥活性的影响。结果表明,投加适宜的海藻糖可以提高厌氧氨氧化菌的活性。在投加海藻糖浓度为0.1 mmol/L时,脱氮效果最佳,NH4+-N、NO2--N、TN去除率分别为70%、73%、63%;与未投加海藻糖相比,能够使TN去除负荷提升26%左右。     

水解-接触氧化法处理啤酒生产废水工艺的挖潜

采用水解-接触氧化(H/O)工艺处理啤酒废水。由于水资源的紧缺，工厂生产工艺进行节水改造，废水浓度及波动幅度均增加。对原有废水处理系统稍加改造，通过回流一沉池厌氧污泥，在保持原有填料固定生长生物量的基础上，增加水解系统中悬浮生长生物量，使水解池调整为类似UASB／AF的预处理工艺，     

两相厌氧工艺处理合成制药废水的分相研究

采用CSTR+UASB两相厌氧系统处理合成制药废水,在动力学控制成功启动的条件下,以钼酸钠(Na2MoO4)为抑制剂进行分相试验研究。试验连续三天向产酸反应器投加浓度为2.0mmol/L的钼酸钠,在此期间以及随后三天的产酸相出水都直接排放而不进入产甲烷反应器,停止投加三天后,两相厌氧系统恢复正常运行。结果表明:经过分相后,产酸相COD去除率降低,但出水VFA和酸化率增加,两相厌氧反应器整体去除效率由80.54%提高到84.20%。     

加弹机上油系统“集中供油和单台面控油”的重点改造

为满足提高拉伸变形丝(DTY)品质的要求,通过分析国内加弹机主要机型上油系统的工作原理及运行状况,根据"集中供油、单机台面控制油位、操作简单、维护方便"的设计原则,对加弹机原上油系统进行改造。上油系统改造后上油率稳定,产品质量提高,工人劳动强度降低,生产效益增加,而且能够满足生产规模进一步扩大的要求。     

UASB处理含甲醇酯类废水的启动及影响因素研究

采用UASB处理含甲醇高浓度酯类废水,在HRT为4 d,COD容积负荷为1.32 kg/(m3.d)时,总COD去除率大于95%,出水COD在300～400 mg/L之间。进水COD、水力停留时间和碱度的投加是UASB启动的关键因素。处理过程中系统内的pH稳定在7.3～7.6,且未出现VFA累积,说明甲醇的降解途径不需经过酸化阶段。     

北方某污水处理厂提标改造设计

以某城镇污水处理厂为例,介绍了该污水处理厂的项目概况及提标改造的设计内容。该污水厂提标改造主体工艺为AO工艺+悬浮填料,本次改造在不增加生物反应池容积的前提下,通过重新划分缺氧好氧段、改造曝气系统、回流系统、更换填料及新增碳源投加系统、次氯酸钠消毒设施使出水水质基本达到设计要求。该改造工程可以为污水处理厂的提标改造设计提供借鉴参考。     

含硫废水治理工艺的改进

生产系统扩产改造后，所产生的工业废水性状也随之变化。原工艺改进势在必行。在分析原废水脱硫工艺原理的基础上，通过投加破乳剂、粗粒化集油、实现油水自动分离等措施改善进水水质，改进原单纯废水脱硫工艺。操作上严格控制氧化反应温度、水风化、反应时间等保证处理效果。运行四年，系统操作平稳、脱硫率≥９０％、除油率≥８０％，控制了污染物的排放，达到了分级控制的目的。     

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。