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针对目前稠油开采和利用存在脱水、降粘难等问题,基于微波热效应与非热效应的原理,利用自行设计的微波辐射实验设备进行研究,系统分析了微波辐射功率和时间对脱水率的影响,以及辐射对胶质和沥青质的影响,并详细介绍了微波辐射工艺中的具体流程。结果表明:微波辐射平均脱水率为90.7%,与普通加热脱水技术的脱水率为34.8%相比,脱水效率高;频率为915 MHz、功率为1 kW 的微波作用1min 后(热效应),油样温度迅速升高到71.2℃,反应速度快;微波辐射(非热效应)后运用四组分测定法,测得油样中沥青质含量减少了2.5%和胶质含量减少了1.2%,油样粘度在低温区发生明显的改变。研究结论为该项技术在工业应用中提供了重要的参考和展望,证明了该技术具有良好的应用前景。 相似文献
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为了研究微波对颗粒煤解吸规律的影响,利用1500W 的微波对粒径为1 ~3mm 的烟煤进行了不同时
间的改性,通过实验室搭建的吸附解吸测试系统进行了各实验煤样在不同吸附平衡压力下的瓦斯解吸实验,并对各
实验煤样的瞬间解吸量、累积解吸量,以及各煤样的比表面积和孔隙分布进行了对比分析。结果表明:随着微波作
用时间的增加,煤样自身得到加热的同时改变了煤样的孔隙结构;主要表现在相同吸附平衡压力下,各实验煤样微
波作用3min 和5min 时的瞬间解吸量和累计解吸量均产生“拐点冶,呈现了先增加后减小,再增加的变化趋势和规
律,且对瓦斯吸附起决定性作用的微孔的比表面积和孔隙体积的分布规律亦出现上述变化趋势;最后初步探讨分析
了微波对颗粒煤解吸特性影响的作用机理。 相似文献
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水分对激光诱导煤粉等离子体特性的影响 总被引:2,自引:0,他引:2
研究了水分对激光诱导击穿煤粉等离子体特性的影响,以分析水分对激光诱导击穿煤粉定量测量的影响.实验选取了空干基C和Si元素含量相近但水分差别较大的神华煤和平朔煤,分别采用其收到基和干燥基共4个样品进行实验.采用Ca的原子谱线计算了各样品在延迟时间分别为83 ns,500 ns,917 ns和1292 ns时的激光诱导击穿等离子体温度,并分别用C247.856 nm和Si390.5523 nm特征谱线估算了电子密度.实验表明,各样品的激光等离子体温度随着延迟时间的增大而降低,含水分的煤样其激光诱导击穿等离子体的温度较低,而电子密度受水分的影响不大,含水分的煤样其激光诱导击穿的特征谱线强度较弱. 相似文献
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为了解决工业上固体材料在微波加热过程中普遍存在的能量不集中、效率低、加热不均匀的问题,提
出了一种管道式固体材料微波加热装置的设计方案。利用多物理场仿真对固体材料微波加热均匀性影响因素进行
分析,并优化了微波馈入装置的分布和管道结构,仿真表明该装置具有较好的加热均匀性和较高的效率。基于优化
后的设计,计算了褐煤在微波加热时的温度分布情况,其温度场的变异系数COV 值达到0.166,表明温度分布具有
良好的均匀性。该装置实现了对褐煤的微波均匀加热,对固体材料微波加热的工业应用具有指导意义。 相似文献
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北方寒冷地区的"煤改电"工程主要应用双级压缩的空气源热泵,与传统的单级压缩热泵相比具有压缩比小、排气温度低、COPh高的优点;为进一步提高双级压缩的性能,利用MATLAB结合REFPROP软件对R410A制冷剂在一级节流中间完全冷却的双级压缩中进行模拟。分析蒸发温度、冷凝温度以及制冷剂流量变化时对制热性能产生的影响,以及这些基本参数变化时对应的最佳工况点,结果发现当蒸发温度在-30℃~-20℃(-18℃~-10℃)之间变化时,最佳中间温度在9℃~11℃(13℃)之间;冷凝温度在35℃~50℃之间变化时,最佳中间温度在9℃~13℃之间;控制高压级的质量流量在2.8kg/s;当室外温度在超低温工况(低温工况)范围内,控制低压级质量流量在1.9 kg/s(2.0 kg/s),能使两级压缩的性能达到最佳状态。 相似文献
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Michele N Berteli Antonio Júnior Marsaioli Elisabeth Rodier 《The Journal of microwave power and electromagnetic energy》2007,40(4):241-250
Drying processes have evolved considerably over the years, aiming at the best conditions to shorten the processing time, but maintaining the highest final product quality. The application of vacuums to the microwave drying process might be interesting, especially for thermally sensitive products because the reduced boiling point of the solvent allows a lower temperature processing. The objective of the present work is to study and evaluate the process of drying a granulated product that is the basis of the drug hydrochlorthiazide, with an initial moisture content of 21% in dry basis. This study monitored the drying kinetics, product temperature and power absorbed by the sample using a bench scale vacuum microwave dryer. The equipment consisted of a cylindrical pressure vessel crossed by a wave guide, setting up a system whereby the vacuum pressure, the sample weight and the incident, reflected and residual microwave powers could be measured and evaluated, throughout the entire process. The experimental runs were established with an approximate incident microwave power at 20 W for absolute pressure levels of 50 and 75 mbar, working with samples of about 1.4 g. It was observed that the vacuum microwave process kinetics at both pressure levels showed little difference. The processes were carried out almost entirely in a regime of water evaporation, the product's temperature remaining below the solvent boiling temperature. The drying times were similar for both processes, whereas the absorbed power was slightly higher at the pressure of 75 mbar. 相似文献
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Satyanarayan Panigrahi Ahmad Ghazanfari Venkatesh Meda 《The Journal of microwave power and electromagnetic energy》2006,40(2):69-77
The feasibility of microwave dehydrating flax fiber was evaluated using a commercial domestic microwave oven at four power settings representing 200, 300, 400 and 500 Watt (W) power level. Due to the possibility of local heating and consequent fiber degradation, the changes in color of the flax fiber at different levels of temperature were also investigated. The dehydration processes at various power levels were simulated by Page model. Based on visual inspection, color analysis and scanning electron microscopy (SEM) of the fiber, it was revealed that discoloration of the fiber occurred at about 170 degrees C. At 200 and 300 W power level, after 10 minutes of dehydrating, the moisture content of the fiber reached from initial 7.9% close to 2.0 and 1.0%, respectively. For 400 W power level, the moisture content of the fiber dropped to 0. 10% in about 9.5 minutes. Major discoloration of the fiber was noticed when dehydration was proceed beyond 4.5 minutes for 500 W treatment. The Page model very well fitted the experimental data. The coefficients of determination calculated from the model and the experimental data increased with increase in applied microwave power 相似文献
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针对激光诱导击穿光谱技术用于水体重金属连续、自动、快速、高灵敏监测中的需求,以石墨为富集基体,采用电磁感应加热技术实现了样品的快速加热与富集,并研究了基于降温斜率的烘干判断方法。实验中以设定140℃判定定时2 s为例,测得从室温上升到140℃用时30 s,温度的误差范围为-5~+3℃,基于降温斜率准确判断了富集完成状态。研究结果表明,采用电磁感应加热技术结合基于降温斜率的富集完成判断方法可以有效实现被测样品的快速加热和准确烘干判断。 相似文献
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随着我国煤电机组综合升级改造步入"深水区",发电厂在对大量的风机和凝结水泵已经进行了变频调速节能改造的情况下,"动刀"号称火电机组"心脏"的液力耦合器调速的电动给水泵已经势在必行了。改造关键是要拿出改动最小、投资最少、节能效果最好的科学合理的改造方案来。 相似文献
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随着我国煤电机组综合升级改造步入"深水区",发电厂在大量的风机和凝结水泵已经进行了变频调速节能改造的情况下,"动刀"号称火电机组"心脏"的液力耦合器调速的电动给水泵已经势在必行了。关键是要拿出改动最小,投资最少,节能效果最好的科学合理的改造方案来。 相似文献
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气介超声可在常温下去除水分,对干燥热敏性水果有突出优势。该文利用有限元仿真软件和实验研究了气介超声在干燥过程产生的微流现象,分析了气介超声对苹果片微观结构的影响,以及在干燥过程中超声功率对水果含水率的影响。结果表明,气介超声干燥后的苹果组织孔隙显著增大,这将有利于苹果内部的水分扩散,同时气介超声能更好地维持样品的微观结构,与未加超声作用的苹果片相比,气介超声处理后的苹果片含水率显著降低,且干燥速率能在短时间内得到迅速提升。上述结果对理解气介超声干燥机制有参考价值。 相似文献
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A multifrequency microwave radiometer of the future 总被引:1,自引:0,他引:1
Le Vine D.M. Wilheit T.T. Jr. Murphy R.E. Swift C.T. 《Geoscience and Remote Sensing, IEEE Transactions on》1989,27(2):193-199