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排序方式: 共有861条查询结果,搜索用时 15 毫秒
1.
Longzhi Li Xiaowei Jiang Zhiguo Bian Jianwei Wang Fumao Wang Zhanlong Song 《Drying Technology》2019,37(2):173-185
Microwave lignite drying with assistance of biomass-derived char was addressed and effect of bio-char on drying rate and energy consumption was investigated in this work. Effective diffusion coefficient and activation energy for the drying process were also analyzed. The results indicated the drying process was largely dependent on the variation of sample temperature. Bio-char originated from pine wood was most favorable for lignite drying, considering its better promoting effect and advanced security. There existed an optimal bio-char addition ratio for drying process at different power. The corresponding optimal ratio was 10% at 231?W and 15% at 385?W, at which the biggest drying rate and the least energy consumption were reached. It was compared lignite drying initiated at 385?W was better for energy conservation. Effective diffusivity was improved and activation energy was simultaneously reduced, with the addition of bio-char. The minimum activation energy was 15.54?W?·?g?1, which was gained at bio-char addition ratio of 10%. The results revealed the effect of bio-char on depressing activation energy could rival that of metal-based additives. The drying process with assistance of microwave and bio-char could present technical and economical benefits on lignite upgrading. 相似文献
2.
在压力高达1—3GPa、温度为400—700℃的条件下,在密闭体系中进行了褐煤加水的模拟实验。分析了实验产物中液态烃的变化规律,并讨论了压力、温度及恒温时间对有机质演化的影响。实验结果表明,热模拟液态产物氯仿沥青“A”的有机碳含量为0.91%-2.55%,2GPa条件下其高峰值后移至700℃,说明高压抑制了液态烃的生成,同时压力升高有利于有机质降解产物的环化、聚合和芳构化。在400—600℃条件下,温度升高或恒温时间增长,OEP和Pr/Ph值均减小;而在700℃的恒温条件下,压力增高,OEP和Pr/Ph值均增大。说明有机质的成熟度与温度和加热时间成正相关,而压力增加抑制了有机质的成熟演化。在高压条件下,芳烃演化的主要趋势是甲基化作用,压力升高有利于甲基化反应和甲基重排。 相似文献
3.
Two lignite samples, Beulah No. 3 and Big Brown No. 1, were liquefied at 420 °C using H2 and synthesis gas to determine the optimum beneficial amount of H2S in the batch autoclave reactor. Under the conditions employed, 50–100 psi partial pressure of H2S, nominally 4–10 wt% of daf lignite, was optimum for both samples. Synthesis gas outperformed H2 with and without H2S for the liquefaction of the two coals. 相似文献
4.
硅化腐植酸钠GFN-1的研制 总被引:1,自引:0,他引:1
针对目前生产腐植酸硅化产品原料受限的缺点,在大量试验的基础上,确定了一条以腐植酸和硅化剂为主要原料的生产工艺,合成了一种与有机硅腐植酸钾(OSAM-K)性能相当的硅化腐植酸钠产品GFN-1,对其常规性能指标和在清水及无固相聚合物钻井液体系中、在膨润土浆和低固相钻井液体系中应用指标,耐温性能进行了对比实验。实验结果表明,GFN-1作为钻井液添加剂,具有良好的降滤失、降黏、耐温及热稳定性,并兼有优良的控制页岩分散能力,其大多数应用性能相当于或略优于OSAM-K,作为替代品完全能够满足油田现场应用的需要。GFN-1的硅化原料性质稳定、来源广泛,生产工艺简单易行,产品质量稳定,具有较好的推广价值。 相似文献
5.
Stephen J. Allen Pauline A. Brown 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,62(1):17-24
The adsorption of the three metal ions, copper, cadmium and zinc in single component and multi-component mixtures in aqueous solutions by lignite is reported. A comparison is made between the single component saturation uptake and the multi-component uptakes. The isotherms indicate a competitive uptake with copper being preferentially absorbed by the lignite in multi-component solutions. The isotherms are plotted to obtain the Langmuir constants, the Freundlich constants and the Redlich–Peterson constants. Lignite is shown to possess an affinity for the metal ions which make its use as an adsorbent a possible alternative to the use of more expensive activated carbons. 相似文献
6.
Michio Shibaoka 《Fuel》1982,61(3):265-270
The behaviour of various huminite macerals and submacerals in a hydrogen-donor solvent, tetralin, at high temperature under hydrogen pressure was investigated. Small granular samples of three Victorian brown coals of different lithotype were treated with tetralin in two types of autoclave, at temperatures of 300–380 °C and under pressures of 5 or 10 MPa. The residual materials were investigated microscopically. This tetralin treatment caused huminite macerals and submacerals derived from highly gelified cellular material to become plastic even at temperatures as low as 340 °C, whereas it had no such effect on those derived from ungelified material. This relation between the degree of gelification and the tendency to become plastic during tetralin treatment in an autoclave is very similar to that found for vitrinite macerals and submacerals from bituminous coals. 相似文献
7.
8.
The combustion behaviour of four different lignite samples pyrolysed at 800 and 1000 °C has been studied. The reaction order and the activation energy of the char combustion reaction can be easily determined from the time to reach 50% conversion. Under 550 °C the reaction order of lignite samples are 0.7 and the activation energies are 27.4–27.9 kcal gmole?1. Above 550 °C the measurement of the intrinsic reaction rate is limited by the film diffusion resistance. The pyrolysis temperature affects the reactivity significantly. The reactivity of char pyrolysed at 800 °C is 3.5 times that of char pyrolysed at 1000 °C. 相似文献
9.
喷动载流床中温度对霍林河褐煤快速热解产物的影响 总被引:8,自引:1,他引:8
在喷动载流床反应器内对霍林河褐煤的快速热解进行了研究,并对该煤的热解机理进行了初步分析。考察了在500~850℃范围内温度对热解产品产率分布及气体和液体产品具体组成的影响。分别利用气相色谱和色质联用仪来分析气体和液体产物的组成。实验结果表明,气体总产率及CO、H2和C1~5烃类的产率随热解温度的提高而增大;在热解温度为650℃时,液体产率最高,在煤粉粒径为0.125~0.18mm,液体产品的总产率可达23%,其中正己烷可溶物的产率可达30%以上,沸点340℃前馏分也达30%以上。液体产品中酚类产品较多;温度对液体产品的组成有极大的影响。 相似文献
10.
Branched-chain/cyclic alkanes have been obtained, by solvent extraction and molecular-sieve adsorption, from a UK low-temperature (Rexco) coal tar, a USA fluidized-bed pyrolysis (FMC COED) coal tar, and a novel supercritical-gas-extract of a Turkish (Elbistan) lignite. Mass spectrometry (with gas chromatography and field-desorption) established the presence of mono-, di (including sesquiterpanes), tri-, tetra- (steranes only), and pentacyclic (triterpanes only) alkanes, including several steranes and triterpanes not previously reported as coal-tar constituents. The potential of cyclic alkanes as geochemical markers, even for commercial coal products subjected to appreciable heat treatment, is demonstrated by the identification of C12, C13, C15 and C16 dicyclics (including isoprenoid alkanes), C17-C26 tricyclics, and C27 and C29 hopane-type pentacyclics (triterpanes) in FMC, and of C16-C38 monocyclics, C34-C36 dicyclics, C22-C36 tricyclics, C27-C30 tetracyclics (steranes), and C27, C29, C30, C31, C32, and C33 hopane-type pentacyclics (triterpanes) in Rexco tar. Tetra- and pentacyclic alkanes were also preserved in the lignite extract. 相似文献