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1.
城镇生活污水回用技术研究   总被引:4,自引:0,他引:4  
针对城镇生活污水的具体特点,采取了先混凝后生化的处理方法,在混凝试验中确定了适合生活污水处理的最佳混凝剂,并通过条件试验确定了使用该混凝剂处理生活污水的最佳工艺条件。试验结果表明:对生活污水采用先混凝后生化的方法,是一种经济实用、适合我国国情的处理方法。经处理后的城镇生活污水达到回用标准,可用于回用。  相似文献   

2.
混凝对垃圾渗滤液中腐殖质的去除特性   总被引:1,自引:0,他引:1  
通过分别投加混凝剂聚合氯化铝(PAC)、聚合硫酸铁(PFS)和聚合氯化铝铁(PAFC)对垃圾渗滤液进行混凝沉淀处理,考察了3种混凝剂对渗滤液中TOC、CODCr和UV254的去除效果,并且根据单因素试验确定出PAC为最佳混凝剂,最佳投药量为6g/L.对渗滤液腐殖质分离方法进行了简化,并对经3种混凝剂处理后水样内的腐殖酸...  相似文献   

3.
周鸣  许景明  耿丹丹 《广州化工》2014,(10):80-82,91
利用混凝-Fenton法对中晚期垃圾渗滤液进行预处理研究。首先以PAC为混凝剂,PAM为助凝剂对垃圾渗滤液进行混凝处理,然后对混凝后渗滤液进行Fenton氧化。考察混凝剂用量,起始pH值,H2O2/FeSO4·7H2O投加比,Fenton试剂投药量和搅拌速度对垃圾渗滤液COD去除的影响,并进行正交试验分析。结果表明:混凝法的最佳投药量为1 L渗滤液投加1.5 g PAC和5 mg PAM;Fenton法的最佳条件为:起始pH值为3,H2O2/FeSO4·7H2O投加比为8∶1,Fenton试剂投药量为135 g/L,搅拌速度为150 r/min;各因素对Fenton试验影响大小为:起始pH值Fenton试剂投药量搅拌速度。在最佳条件下,混凝-Fenton法对垃圾渗滤液COD去除率可达91.41%。  相似文献   

4.
垃圾焚烧厂渗滤液生化出水混凝处理及其模型的建立   总被引:1,自引:0,他引:1  
对采用聚合氯化铝、硫酸铝和氯化铁等混凝剂处理焚烧厂垃圾渗滤液生化出水的混凝效果及其模型进行了研究.结果表明:聚合氯化铝对焚烧厂垃圾渗滤液中CODCr、色度和浊度的去除效果比硫酸铝和氯化铁要好,且投加量相对也较少.在投加量500 mg/L、中性条件下,CODCr、浊度和色度的去除率可分别达到28.9%、91.6%和77.6%.在不同投药量、pH和搅拌速度下,PAC保持了良好的污染物去除效果,而对硫酸铝和氯化铁的处理效果影响较大.各种混凝剂的最佳投药量与起始CODCr浓度之间的关系可采用指数关系式表达.通过对PAC在各条件下混凝效果的统计分析,采用Matlab优化工具软件,建立了垃圾焚烧厂垃圾渗滤液PAC混凝处理的处理效果数学模式方程,其与试验结果的相关系数可达到0.982,表明建立的模型与混凝处理效果较为一致.  相似文献   

5.
混凝-SBR工艺处理垃圾渗滤液的研究   总被引:6,自引:0,他引:6  
:对混凝-SBR工艺处理生活垃圾渗滤液进行研究,确定了混凝剂的种类、用量以及pH值、生化时间等技术参数。研究结果表明,采用聚合氯化铝铁混凝-SBR生化处理工艺,能够使垃圾渗滤液的CODCr值从5000~14000mg/L降低到200mg/L以下,BOD5值从1800~5600mg/L降低到100mg/L以下,NH3-N值从47~374mg/L降低到15mg/L以下。  相似文献   

6.
采用混凝沉淀-Fenton氧化处理垃圾渗滤液生化处理出水,通过单因素试验研究了混凝沉淀和Fenton氧化中各因素对去除CODCr的影响,试验结果表明,最佳混凝试验工艺条件为:复合混凝剂比例n(无机组分)∶n(有机组分)为4.0∶1、p H值为8.5、混凝剂投加量0.6 g/L,CODCr的去除率可达到88.6%。Fenton氧化阶段,当体系p H值为4.0、H2O2投加量为16 mg/L、Fe SO4·7H2O投加量为6 g/L、反应时间为110 min时,CODCr去除率高达95.9%。  相似文献   

7.
采用混凝沉降法对垃圾填埋场所产生的垃圾渗滤液进行处理,以处理出水的CODcr、电导率、脱色率和浊度等作为处理程度的表征指标,考察不同用量的混凝剂聚合氯化铝(PAC)对垃圾渗滤液的处理效果。实验结果表明,垃圾渗滤液的处理效果随着混凝剂用量的增大而增强,混凝剂PAC最佳用量:30 g/L。垃圾渗滤液处理后,CODcr去除率达到36.45%,脱色率达到84.0%,电导率由原来的1.55×104 S/cm降低到处理后的0.94×104 S/cm,浊度也有一定程度的降低。  相似文献   

8.
利用粉煤灰和废旧铝皮在一定条件下反应,制得粉煤灰基混凝剂,并用于处理垃圾渗滤液中的铬离子。试验结果表明,粉煤灰基混凝剂对垃圾渗滤液中的铬离子有较好的去除效果。在最佳条件下,粉煤灰基混凝剂对垃圾渗滤液中铬离子的去除率达96.3%,比普通粉煤灰的去除率提高了70.4%。  相似文献   

9.
余文腾  许越  张永利 《当代化工》2010,39(6):661-663,705
采用正交试验,对高浓度有毒有害垃圾渗滤液进行混凝预处理。对单组分混凝剂进行筛选,通过处理垃圾液COD去除率进行评价,得出单组分最佳用量为1 250 mg/L(PAC)、1 500 mg/L(PFS)、50 mg/L(PAM)。对3种混凝剂进行双组分及多组分的复配,确定复配的最佳剂量比值为PAC/PFS/PAM=1︰1︰1。实验结果表明,复配的混凝剂比单组分混凝剂的垃圾液预处理效果明显提升。  相似文献   

10.
针对武进夹山垃圾填埋场渗滤液处理工艺设计及运行过程中存在的问题,提出了厌氧与SBR-混凝法相结合的渗滤液处理工艺改进方案。研究表明:SBR及混凝处理的CODcr最大去除率分别达42.5%、63.0%,可以达到国家渗滤液排放的二级标准(GB16889-1997)。SBR法处理垃圾渗滤液的影响因素依次为曝气时间、闲置时间和污泥浓度:正交试验得出的最佳工艺条件是:曝气时间30h,  相似文献   

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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   

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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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