COD对生物流化床法降低污泥回流液中氮磷的影响

以市政污水处理厂污泥回流液为研究对象,研究了不同碳、氮、磷水平条件下生物流化床法脱氮除磷的情况,分析了COD/TN与COD/TP对生物流化床脱氮除磷的影响.结果表明,COD对脱氮影响不大,而对除磷具有较大影响.在COD为500 mg/L,进水TN为115 mg/L时,TN的去除率最大值为72.05%,此时,COD/TN为4.35.在COD为480 mg/L,进水TP为11.25 mg/L时的去除率较高为36.98%,此时COD/TP为42.67.生物流化床法对高浓度氮磷污泥回流液具有一定的脱氮除磷效果,TN去除率可达56.35%,TP去除率为28.96%.     

北方滨海城市道路的人工降雨径流污染特征分析

为了解北方滨海城市道路径流污染物特征,选择青岛作为典型城市,以人工降雨的方式模拟1年、2年、3年和5年一遇4类重现期降雨条件,通过收集道路径流,并对悬浮固体(SS)、氨氮(NH3-N)、总氮(TN)、总磷(TP)、COD等污染物指标进行测定,分析主要污染物浓度变化规律、平均浓度(EMC)及相关性.结果表明,主要污染物初始浓度随着径流在1～6 min时达到峰值,而后逐渐降低,且在20min后趋于平稳.在4类不同重现期降雨条件下,SS的平均浓度为43～91 mg/L,NH3-N为0.15～1.01mg/L,CODCr为66～104 mg/L,TN为4.2～4.9 mg/L,TP为0.06～0.11 mg/L,其中COD和TN均超过了地表水环境质量V类标准.SS与NH3-N、COD、TN、TP均呈现正相关关系.将SS作为径流污染控制指标,确定了SS控制率与设计降雨量关系式,为北方滨海城市的海绵城市建设与降雨径流污染控制提供理论支撑.     

麦草秸秆CTMP废水UASB-SBR-深度处理

麦草秸秆化学热磨机械浆(CTMP)废水含有较高的COD及氮、磷含量,采用升流成厌氧反应(UASB)-序批式反应器(SBR)-深度处理三段工艺,在不添加任何营养盐的条件下,对其进行处理研究。结果表明,在UASB厌氧阶段进水体积负荷为6kg/(m³·d),SBR处理进水COD 1 400mg/L,曝气时间为24h,缺氧搅拌25min,深度处理自制药剂A用量为0.15%时,处理效果良好,可使废水出水COD为 71.18mg/L,总氮(TN)为5.43mg/L、总磷(TP)为0.71mg/L,色度为33,达到国家排放标准。     

麦草秸秆CTMP废水UASB-SBR-深度处理北大核心

麦草秸秆化学热磨机械浆(CTMP)废水含有较高的COD及氮、磷含量,采用升流成厌氧反应(UASB)-序批式反应器(SBR)-深度处理三段工艺,在不添加任何营养盐的条件下,对其进行处理研究。结果表明,在UASB厌氧阶段进水体积负荷为6 kg/(m^3·d),SBR处理进水COD 1 400 mg/L,曝气时间为24 h,缺氧搅拌25 min,深度处理自制药剂A用量为0.15%时,处理效果良好,可使废水出水COD为71.18 mg/L,总氮(TN)为5.43 mg/L、总磷(TP)为0.71 mg/L,色度为33,达到国家排放标准。     

重金属镉胁迫下好氧颗粒污泥脱氮除磷特征分析

为探究重金属镉(Cd)胁迫下,好氧颗粒污泥培养及脱氮除磷的特征,以絮状物质为探究对象,采用摇床震荡并添加不同剂量Cd胁迫下好氧颗粒污泥的形成及脱氮除磷特征。结果表明在低浓度Cd(0.1mg/L和0.5 mg/L)时,颗粒污泥浓度增加,污泥沉降性加强,而当Cd质量浓度为3.0 mg/L,颗粒污泥稳定时期混合液悬浮固体(MLSS)浓度下降至2.16～2.19 g/L,污泥体积指数(SVI)升高至124.6～129.5 m L/g。进水Cd影响颗粒污泥脱氮除磷,0.1 mg/L和0.5 mg/L Cd提高总氮(TN)去除效率至81.5%～82.3%和83.4%～83.6%,而当3.0 mg/L Cd降低TN去除效率至54.9%～55.6%。低浓度Cd对总磷(TP)去除影响不明显,而高浓度Cd抑制TP去除。元素分析表明Cd浓度降低颗粒污泥表面Na与Ca的含量。     

海绵铁与火山岩填料A/O生物滴滤池脱氮除磷的中试研究

以火山岩矿物为填料,进行了A/O生物滴滤池脱氮除磷的中试现场试验。通过内部设置缺氧段,采用海绵铁强化除磷的方法,提高了滴滤池的脱氮除磷能力。结果表明,A/O生物滴滤池对TN、NH3-N、TP、COD均有较理想的去除效果,特别是TN和TP;当进水TN、TP质量浓度分别为51.0～56.8 mg/L和4.99～5.32 mg/L时,去除率平均可达79%和84%,比普通生物滴滤池分别高约35%和50%;出水质量浓度分别为12 mg/L和1.0 mg/L左右。出水TN可达城镇污水处理厂污染物排放标准(GB 18918-2002)中一级A排放标准,TP接近一级B排放标准。     

碳磷比和污泥龄对一体化工艺同步脱氮除磷的影响

基于节能减排提效理念,改进现有OCO工艺,将沉淀池构建于主反应器一侧,得到一体化OCO工艺。以改进工艺处理模拟生活污水,在进水TN约为40 mg/L的条件下,通过改变剩余污泥排放量和进水COD、TP浓度,研究污泥龄和碳磷比对工艺脱氮除磷的影响,探讨工艺运行的优化策略。试验结果表明:(1)污泥龄为12 d是脱氮除磷的一个平衡点,此时COD、NH4+-N、TN、TP的去除率分别达到94%、99%、80%和92%;(2)稳定进水TP浓度为5 mg/L,改变COD浓度,使C/P比为20~120,当C/P比为60时,COD、NH4+-N、TN、TP去除率分别达到90%、99%、80%和90%;(3)稳定进水COD浓度为300 mg/L,改变TP浓度,使C/P比从15增加为60,当C/P比为30时,COD、NH4+-N、TN、TP去除率分别达到93%、99%、80%和91%。     

生活污水脱氮除磷的工艺设计

以泰州市紫光水业污水处理厂初沉池出水和曝气池的活性污泥制作一定浓度的污泥混合液,通过测定COD、TN、TP、NH3-N等指标发现自制的可移动悬浮式曝气设备脱氮除磷处理效果非常好。进水COD=324.6mg/L,TP=6.04mg/L,NH3-N=49.3mg/L,TN=56.4mg/L,出水COD=28.7mg/L,去除率为91.2%,TP=0.49mg/L,去除率为91.9%,NH3-N=8.02mg/L,去除率为83.7%,TN=12.7mg/L,去除率为77.5%。出水达到了我国《城镇污水处理厂污染物排放标准》(GB18918—2002)。     

新型一体化工艺处理生活污水的脱氮除磷研究

对新型一体化OCD生物反应器处理生活污水的脱氮除磷进行了试验研究.在污泥龄为15天,进水流量为20L/h,水力停留时间为12h的条件下,通过连续3个月的监测数据表明:化学需氧量(COD)、总氮(TN)和总磷(TP)的去除率分别在95%、80%和90%以上.对中心岛多斗式沉淀池进行观察研究,表明沉淀池具有较好的分离作用.出水悬浮性固体(踢)的质量浓度基本维持在15～20 mg/L.同时对系统内活性污泥进行连续监测,发现本装置系统中生物种类数量丰富,微生物优势种群及其数量随环境变化而波动,呈现一定的规律性.     

混合型城市污水强化脱氮除磷工艺试验研究

采用膜膜强化集成工艺,对混合型城市污水进行脱氮除磷效果试验研究。试验结果表明,COD、NH3-N、TN及TP去除率分别达到80%、96%、60%及88%,系统平均出水COD为25 mg/L,NH3-N、TN及TP的质量浓度分别为0.9、13、0.44 mg/L。系统运行稳定,各项指标均可达到国家一级A标准(GB 18918-2002)。     

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.     

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。     

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.