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排序方式: 共有2135条查询结果,搜索用时 16 毫秒
1.
Alok K. Singh Mrityunjay K. Jha 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(2):163-171
The present study investigates the hydrocarbon generative potential of the coal seams of Barka Sayal Area of South Karanpura Coalfield, India, using petrological and geochemical characteristics. These coals are vitrinite rich followed by liptinite and inertinite. Rank wise these are sub-bituminous ‘A’ to high volatile bituminous ‘C’ and fall in the early catagenesis stage of evolution. The presence of Type III kerogen and high hydrogen index value indicates excellent gaseous hydrocarbon generative potential, but low Tmax suggests a characteristic of immature source rock. The calculated high conversion (%) and sufficient oil yield (%) justifies the suitability of these coals for liquefaction processes. 相似文献
2.
对杨木粉与大豆油或脂肪酸甲酯在超临界甲醇中的共炼进行了研究,以验证油脂及其甲酯对杨木粉液化的促进作用。研究结果表明,大豆油及脂肪酸甲酯都对杨木粉的分解率有明显促进作用,且大豆油的促进效果要优于脂肪酸甲酯。更进一步研究表明,共炼能够同时提高木粉中纤维素、半纤维素和木质素的分解率,其中木质素的相对分解率提高幅度最大。生物质共炼产物在经过低温减压蒸馏、石油醚萃取分离后得到两部分:生物轻油,以油脂衍生物为主;生物重油,以杨木粉液化产物为主。如果原料中采用的油脂不饱和度越高,则产物中会含有越多的甘油二酯沸程的化合物,这部分甘油二酯沸程化合物主要是有油脂衍生物与杨木粉液化产物缩合而成。另外,共炼所得到的生物重油产率要远高于杨木粉在超临界甲醇中直接液化的产率,本文对可能的原因进行了分析。 相似文献
3.
Sekove Vodo Kunihiko Uemura Mitsutoshi Nakajima Marcos A. Neves 《International Journal of Food Science & Technology》2021,56(12):6697-6706
Synthetic emulsifiers in food industries are being replaced with a customer-friendly food ingredient that is derived from biomass using sustainable green technologies. After hydrothermal liquefaction treatment, raw bagasse (21%), pith (26%), and rind portions (25%) were obtained with reduced ash contents. As aqueous extracts, with oligosaccharides and lignin residues, it was used in the preparation of oil-in-water emulsions with 5% soybean oil. Results showed that the emulsions stabilised the oil droplets with particle size between 11 and 17 µm by steric repulsion with raw bagasse-stabilised emulsion showing a better stability at 25 °C (31 days). It was demonstrated that raw bagasse extracts, without alteration, maybe a potential unconventional source for food-grade emulsifiers by integrating a versatile thermochemical conversion of waste without the use of chemicals. 相似文献
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Peng Li Yu-Qing Zhao 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(10):1266-1272
Shenmu-Fugu coal liquefaction residue (SFCLR) was ultrasonically extracted with methanol, ethanol, and isopropanol, respectively. Abundant of condensed arenes (CAs) were identified in the extracts using gas chromatography/mass spectrometer (GC/MS) by quantitative analysis, besides some alkanes and heteroatom-containing compounds. The most dominant CAs is benzo[ghi]perylene with its yield of 71.77 mg/g in isopropanol extract based on GC/MS analysis. Series of alkanoates were identified in the extracts from SFCLR with high yields. Interestingly, methyl alkanoates were identified in each of the three extracts, while ethyl and isopropyl alkanoates were only identified in the ethanol and isopropanol extracts, respectively. Accordingly, we presume that transesterification of methyl alkanoates with ethanol or isopropanol occurs during the ultrasonication-assisted solvent extraction. 相似文献
7.
Nils von Preetzmann Philipp Eckmann Adriaan M. H. van der Veen Jianrong Li Markus Richter 《American Institute of Chemical Engineers》2021,67(4):e17128
Exact knowledge of natural gas composition is essential in custody transfer to determine the energy content of the delivery. However, for liquefied natural gas (LNG), a reliable composition determination is difficult. Here, we describe the design of a laboratory-scale reference liquefier that enables the validation and calibration of optical spectroscopy sensors by providing them with a sample of metrologically traceable composition. Hence, it is crucial to avoid fractionation of the sample during liquefaction. This is realized by supercritical liquefaction of a reference gas mixture in conjunction with a special vapor–liquid-equilibrium (VLE) cell. As this is a demanding high-pressure application, low-pressure condensation as liquefaction method was also assessed. Through experimental investigations and VLE calculations, preservation of the composition of the produced liquid sample during condensation was studied. We conclude that under optimized conditions, validation, and calibration measurements of optical sensors can be performed on condensed liquids, which, however, needs further confirmation. 相似文献
8.
In the present work, an advanced hydrogen liquefaction system with catalyst infused heat exchangers is proposed, analyzed and assessed energetically and exergetically. The analysis starts with exergetic considerations on hydrogen liquefaction using different alternatives of pre-cooling including the conversion from normal to parahydrogen. It further explains the fundamentals of a proposed liquefaction process. The goal is then to assess the proposed system, make modifications and improve the system. The present system covers all of these portions of a hydrogen liquefaction system with an ultimate goal of achieving a sustainable and environmentally harmless system. The proposed hydrogen liquefaction system is simulated in the Aspen Plus and the performance of the system is measured through energy and exergy efficiencies. The resulting energy efficiency of the system is calculated to be 15.4%, and the exergy efficiency of the system is found to be 11.5%. 相似文献
9.
Hua Zhao Michael S Franklin 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2020,95(9):2301-2310
Coal is the most abundant fossil fuel. Direct combustion of low- and medium-rank coals causes alarming environmental impacts. Therefore, it is crucial for coal to undergo pretreatments before its efficient utilization [such as coal to liquid (CTL) processes]. Conventional pretreatment methods suffer from several limitations including the use of volatile organic solvents, environmental hazards, strong reaction conditions (e.g. high temperature and pressure), consumption of large quantities of nonrecoverable chemicals (e.g. bases used in aqueous alkaline digestion), or being only effective for specific coals. On the other hand, coal pretreatment by nonvolatile ionic liquids (ILs) could lead to partial coal dissolution/swelling and structure disruption, which is a critical step before coal liquefaction, hydrogenation, pyrolysis or the inhibition of oxidation/combustion. In addition, ILs are suitable solvents for extracting sulfur compounds from coal, asphaltenes from Direct Coal Liquefaction Residues (DCLR) and phenolic compounds from coal tar. This review will discuss these aspects of coal pretreatments by ILs, and identify how ILs could lead to a cleaner and more efficient utilization of coal resources. © 2020 Society of Chemical Industry 相似文献
10.
详细介绍了国内外煤油共炼技术的发展现状,分析了煤油共炼的技术优势及发展前景,并对我国煤油共炼产业化现状进行分析思考。认为:煤油共炼是在煤直接液化技术基础上探索形成的一种新型工艺技术,与煤炭单独液化技术相比具有诸多优势,实现了现代煤化工技术与重(劣)质油加工的耦合,为我国煤制油和重(劣)质油轻质化开辟了一条全新的技术路线,具有良好的产业化前景。目前我国煤油共炼技术正处于工业示范阶段,还有一些技术问题需要解决。为加快推进煤油共炼技术进步,建议煤化工行业与石油炼制行业加强合作、优势互补,共同推动煤油共炼技术创新,早日取得突破,以先进成熟的煤油共炼技术支撑煤化工与石油化工深度融合发展。 相似文献