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利用高压釜和加压固定床反应器,通过对水热改质前后煤的工业分析、元素分析以及水热改质废水气化过程中的碳转化率、气体产物分析,研究了内蒙褐煤在不同温度下的水热改质效果及水热改质废水在催化剂作用下的气化特性.结果表明,水热改质可以脱除煤中水分,降低氧含量,提高固定碳和元素碳含量;水热改质废水中有机质的气化反应活性较好,催化气化时气化速率和碳转化率较高;气化能将水中的含碳有机质转化为可回收利用的燃气,燃气的主要成分为H2,CO2和CH4,而CO含量很少. 相似文献
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运用超临界水气化技术,在间歇式高温高压反应釜内,分析对比了KOH,K2CO3,Na2CO3和Ca(OH)2四种碱性催化剂及ZnCl2,FeCl3,CuCl2和AlCl3四种金属氯化物催化剂对褐煤在超临界水中气化反应制取CH4的影响.研究表明,反应条件为550℃,25MPa,水煤比10∶1,KOH与煤的质量比为20%,停留时间20min时,CH4产量由高到低的顺序为:KOH>K2CO3>ZnCl2>Na2CO3>AlCl3>Ca(OH)2>不加催化剂>FeCl3>CuCl2.实验发现,ZnCl2对CH4产量有促进作用,其主要原因为ZnCl2具有能促进中间产物降解生成酸,有利于酸催化反应,从而能更好地促进气化反应的进行.而KOH催化效率最高(110.2mL/g daf coal),比不添加催化剂时增加了1倍多,其主要原理为KOH在超临界水中的自由基反应及碱性金属对水气置换反应的促进作用. 相似文献
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研究了锡林郭勒褐煤在超临界水和N2气氛下,以及K2CO3,FeS+S和KOH三种催化剂分别作用下的液化性能,并与其在供氢溶剂四氢萘和H2气氛下的液化性能进行比较。结果表明:锡林郭勒褐煤在供氢溶剂四氢萘和H2气氛下具有较高的液化活性,在420℃、无催化剂条件下褐煤的液化转化率和油水气收率分别为76.8%和51.0%;而在相同温度、添加5%甲酸的超临界水和N2气氛下,褐煤的液化转化率和油水气收率分别降为32.0%和29.2%,且褐煤液化主要转化为附加值高的油气部分。K2CO3,FeS+S和KOH三种催化剂对锡林郭勒褐煤在超临界水中液化都具有较好的催化活性,按催化活性由高到低排序为K2CO3,FeS+S,KOH;420℃时K2CO3对锡林郭勒褐煤具有最好的催化效果,褐煤的液化转化率和油水气收率最高,分别为46.5%和42.2%。气氛对锡林郭勒褐煤在超临界水中的液化性能具有较大的影响,在CO气氛下锡林郭勒褐煤的液化活性最高,420℃时褐煤的液化转化率和油水气收率最高,分别为52.2%和44.4%。这是由于在CO气氛下能够发生水煤气变换反应,可以为液化过程提供原位活性H,从而促进了油气收率和液化转化率的提高。 相似文献
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采用间歇式超临界水反应装置,以滇池疏浚底泥和褐煤为原料,分别将褐煤、底泥单独进行超临界水气化,对比不同反应原料对气化制氢的影响。再将二者按不同混合比例(1∶9、2∶8、 3∶7、4∶6、5∶5)进行共气化,对比不同混合比例对气化制氢的影响。结果表明,相对褐煤,底泥气化具有气体组分富氢、气相收率高、产气量小的特点;褐煤气化则具有碳气化率高、产气量大的特点。褐煤单独气化的气相收率低于底泥,共气化时气相收率达到834 mL/g。褐煤和底泥在超临界水共气化过程中碳气化率和产氢率存在明显协同效应。与加权平均值相比,碳气化率和H2产率分别提高了3.12%和55 mL/g。共气化存在最优比例,超过3∶7后,碳气化率逐渐下降。以最优比例进行共气化,既可达到处置底泥的目的,又可保持相对较高的H2产率(350 mL/g)和CH4产率(113 mL/g)。 相似文献
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采用Gibbs自由能最小原理,建立了生物质超临界水气化制氢的化学平衡模型。将该模型应用于玉米芯/羧甲基纤维素钠(CMC)的超临界水气化制氢,分析模拟和实验结果,得到反应温度对化学平衡产物的作用如下:在300—374℃的亚临界区,气体产物的摩尔分数排序为x(CO2)>x(CH4)>x(H2),在375—420℃的低温超临界区,气体产物排序为x(CO2)>x(H2)>x(CH4),在420℃以上的高温超临界区,H2摩尔分数跃居最高,可达65%以上。较高的反应温度有利于提高H2的摩尔分数和气化率,但降低了气体的高热值。获得玉米芯/CMC制氢的最佳温度范围为420—600℃。表明农业废弃物的超临界水气化制氢是一种极具发展前景的能源转化新技术。 相似文献
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为了考察煤炭地下气化工业试验基地废水的催化活性,探究利用该废水进行地下催化气化工业性试验的可行性,对乌兰察布褐煤进行了不同压力下的活性评价实验.结果表明,煤炭地下气化废水对乌兰察布褐煤的气化起到了良好的催化效果,在添加一定量煤炭地下气化废水后,其碳转化率由80.19%提高到89.82%;煤气产率由4.2m3/kg增加到5.2m3/kg,增加了原来的23.8%.随着反应压力的提升,碳转化率及煤气产率均呈现不同程度的降低,煤气组分中H2,CO和CO2含量也呈现不同程度的降低;而CH4含量随着压力的提升持续增加. 相似文献
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感冒清热颗粒中药渣中试规模循环流化床气化实验 总被引:2,自引:0,他引:2
以感冒清热颗粒中药渣为原料,在双回路循环流化床中试设备中进行热解气化实验,研究原料含水率、原料粒径以及空气当量比ER对其气化特性的影响。结果表明:①随着原料含水率的提高,炉内平均温度降低,产生的燃气中焦油含量、CO2含量明显提高;CO含量、气体产率、碳转化率显著降低;H2含量、燃气热值以及气化效率均呈现先增大后减小的趋势。②原料粒径越小,反应炉内平均温度越高,燃气中焦油含量越低,燃气热值和气体产率越高,气化效率以及碳转化率越高;H2、CH4、CO、CnHm含量增加,CO2含量减少。③随着ER的增大,可燃气体尤其是CO的浓度不断降低,CO2含量不断增加;炉内平均温度、气体产率以及碳转化率均逐渐增大;燃气热值和燃气中焦油质量浓度逐渐减小;气化效率则呈现先增大后减小的变化趋势。④当原料含水量<9%、原料粒径<4mm以及ER在0.25~0.27时,气化效率较高,具有较好气化特性。 相似文献
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锯木屑在超临界水中气化制氢过程的主要影响因素 总被引:8,自引:1,他引:8
以锯木屑混合羧甲基纤维素钠(CMC)为反应原料,利用连续管流反应器,在反应器外壁面温度稳定在650 ℃条件下,对反应压力在17.5~30 MPa,反应停留时间在14.4~50 s,浓度范围为4%~9%(质量分数)的湿生物质浆液进行了超临界水气化制氢实验研究,讨论了气化过程的主要参数压力、温度、反应停留时间以及物料浓度对气化结果的影响.锯木屑在超临界水中接近完全气化,生成气体产物的主要成分是H2、CH4、CO、CO2以及少量的C2H4和C2H6,气化产物中的H2含量可以超过40%.同时,实现了气化反应液体产物的循环利用. 相似文献
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为获得较低温度下生物质焦油高效裂解气化的廉价型催化剂,基于褐煤富含含氧官能团特点,通过离子交换法将镍负载到胜利褐煤上制备褐煤负载镍催化剂(Ni/SLC)。研究了溶液p H值和炭化温度对催化剂物理化学性质的影响,得到Ni/SLC催化剂最佳制备条件,最后在两段式移动床石英反应器中将催化剂用于玉米芯挥发分的催化气化,研究了催化剂对生成气产量和碳平衡的影响。结果表明:p H值为11,炭化温度为650℃时制备的Ni/SLC比表面积最大达到266.3 m2/g,镍微晶尺寸较小为5.0 nm。催化气化实验表明:650℃下Ni/SLC催化剂具有高的焦油裂解活性,气体产量高达43.9 mmol/g,相当于无催化实验气体总产量的3.3倍;水蒸气气化可将热解焦油完全气化,气体产量为85.1 mmol/g,H2产量高达61.9 mmol/g,占气体总量的72.7%,说明Ni/SLC催化剂可作为生物质催化气化制氢的潜在催化剂。 相似文献
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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
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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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
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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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. 相似文献
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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
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中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2009,37(3)
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
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中蓝晨光化工研究院《塑料工业》编辑部 《塑料工业》2007,35(3):1-25,67
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