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为考察神华上湾煤的直接液化性能及反应动力学,以加氢蒽油-洗油混合油作为溶剂、负载型FeOOH作为催化剂,在0.01 t·d-1煤直接液化连续实验装置上考察了不同反应温度(435~465℃)、不同停留时间(7~110 min)下液化产品组成的演变规律。研究发现,随着煤的裂解及加氢反应的进行,煤及沥青类物质(PAA)收率不断减小,重质液化产物逐步向轻质液化产物转化。当反应温度为455℃、停留时间为90 min时,煤转化率为90.41%(质量分数(,油收率为61.28%(质量分数(。随着反应条件进一步苛刻,油收率下降。基于上湾煤直接液化反应特性及其产物收率变化规律建立了11集总煤直接液化反应动力学候选模型,以BFGS优化算法对实验数据搜索、选优,确定了动力学模型参数。检验结果表明所建立的动力学模型可用于恒温阶段直接液化行为的模拟计算。 相似文献
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煤焦CO2气化的热重分析研究:(II)程序升温热重研究 总被引:2,自引:2,他引:0
用程序升温热重法(Temperature-ProgrammedThermogravimetry)对内蒙扎贲诺尔煤(ZL),陕西神府煤(SF),山西阳泉煤(YQ)的800℃半焦进行CO2气化研究,对表征煤焦反应性的参数变化进行了分析讨论和动力学计算,并与等温法的结果相比较,结果表明:DTG参数是对煤焦气化反应的动态扫描,由此得出的煤焦活性顺序和动力学参数值,与等温法的研究结果不同,这种差异是由于不同 相似文献
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在现有实验室条件下,全面分析了6种形式的生物质与煤共热解过程,考察其中的协同反应效应,利用分布活化能法(DAEM)研究生物质与煤的共热解动力学特性,得出共热解动力学相关参数,为实现生物质与煤高效协同共热解反应寻找更为有效的途径。主要内容和研究成果归纳如下: 相似文献
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利用恒温和程序升温热重技术研究了神木煤半焦的燃烧动力学,采用DAEM(分布活化能模型)和Coats-Redfern积分法对其进行了动力学分析,比较了二者在处理程序升温半焦燃烧反应动力学的差异,同时还对恒温及程序升温的燃烧动力学进行了分析.结果表明,在恒温燃烧和程序升温燃烧过程中,随着燃烧反应的进行,比燃烧速率逐渐增加,所得半焦燃烧的活化能有不同的变化趋势.DAEM和Coats-Redfern 积分法因所用方法的不同而使结果有所差异.而恒温燃烧时由于所用燃烧温度较低,可以最大限度地消除外扩散的影响,使所得动力学参数更接近半焦燃烧的本征动力学参数. 相似文献
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煤中黄铁矿的电化学脱硫及动力学研究 总被引:2,自引:1,他引:2
为了降低煤的脱硫费用和提高脱硫效率,以硫酸为介质,以硫酸锰为脱硫催化剂,在以石墨为电极的无隔膜电解池中研究了煤的电化学催化脱硫。研究表明,在特定的电解电位下,煤中无机硫脱硫率随着锰离子的浓度增加,煤浆浓度的降低和电解温度的提高而提高。进而对这些数据进行了动力学分析。结果表明:煤中黄铁矿脱硫速率与煤中活性黄铁矿(易接近)和惰性黄铁矿(难接近)及脱硫反应有关,脱硫模型符合Langmuir-Hinshelwood近似,脱硫表观活化能为10.44kJ/mol。 相似文献
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In recent years, a number of direct coal liquefaction processes have been developed. All processes use a slurry type reactor. Although for lab-scale reactors of large length-to-diameter ratio the use of highly sophisticated slurry reactor model may be justified, simple considerations can meaningfully elucidate the behavior of industrial reactors. A simple analysis shows that the coal liquefaction is controlled by intrinsic kinetics. Both gas and slurry phases can be assumed to be completely backmixed in large diameter reactors. A simple analysis of the thermal behavior revealed multiplicity for a fairly wide range of operating conditions. In most cases, the intermediate unstable steady state is close to the temperature observed in adiabatic coal liquefaction reactors (with and without quench). Due to the unstable character of the operation, point pathological phenomena like runaway may be possible and a close feedback control of the commercial reactor may be required. 相似文献
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甲醇制烯烃(MTO)工艺是现代煤化工领域的研究热点,MTO反应动力学及其反应器模型研究是高效反应器开发和工业装置操作优化的基础。本文综述了甲醇制烯烃反应动力学研究进展,详细论述了机理型动力学模型、八集总动力学模型、五集总动力学模型,指出集总动力学模型适用于描述MTO反应过程,如何考虑水、积炭等因素的影响是MTO动力学研究的难点和关键。结合现有动力学模型,评述了MTO反应过程在工业规模的固定床反应器、提升管反应器、循环流化床反应器、湍动流化床反应器中产物分布和转化率模拟情况,结果表明:循环流化床反应器和湍动流化床反应器适合MTO工业过程。最后指出,甲醇制烯烃反应动力学下一步研究方应集中于工业规模流化床反应器气固两相流动模拟,以及与动力学模型结合获得准确预测工业反应结果的MTO反应器模型。 相似文献
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Design of laboratory reactors for the measurement of catalytic carbon and coal gasification kinetics
William L. Holstein 《Fuel》1983,62(2):259-261
A great deal of conflicting experimental kinetics results have appeared for catalytic carbon and coal gasification by water and carbon dioxide. The reason for this can in large part be attributed to inhibition of these reactions by their products and the influence of this product inhibition on the measured kinetics in different laboratory reactor systems. The measurement of differential rates and the determination of true kinetic values requires the use of feed streams with an excess of water and hydrogen for the catalytic CH2O reaction and an excess of carbon dioxide and carbon monoxide for the catalytic CCO2 reaction. Recommendations are put forward for the design of laboratory reactors for the measurement of catalytic carbon and coal gasification kinetics. 相似文献
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Harald Jüntgen 《Fuel》1983,62(2):234-238
There are several processes used for coal gasification, but these have three characteristic types of reactors — moving-bed, fluidized-bed and entrained phase. Design and comparison of different processes and reactors is possible if kinetic data relevant to technical performance of processes are available. The state of reaction kinetics of the non-catalysed and catalysed steam-carbon reaction as the basic coal gasification reaction is discussed. Catalysts only have effects on gasification rates in the temperature range of chemical reaction or pore diffusion control. Furthermore the increase in reaction rates by catalysts can also be reached without using catalysts. Therefore the application of catalysts seems not to be attractive in conventional gasification processes because the advantages (less coal and oxygen consumption and lower heat losses) are compensated by their disadvantages (additional costs, side effects). Only such processes in which a temperature increase is limited for different reasons does the application of catalysts have significant advantages. Such processes are the allothermal gasification using nuclear heat and processes leading to synthetic natural gas (SNG). 相似文献
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Karl Heinrich Van Heek 《化学,工程师,技术》1983,55(10):777-784
Kinetics of coal pyrolysis as a foundation for the design of technical reactors . The pyrolysis of coal is understood to mean its thermal decomposition at temperatures above 300°C, affording tar and char. It is the basic process underlying coking and the starting reaction of combustion, gasification, and hydrogenation. In addition, pyrolysis offers a means of converting coal into gases and liquids in a ?third way”? besides gasification and hydrogenation. In order to establish a basis for the design of relevant technical reactors, the kinetics of coal pyrolysis has been investigated as a function of temperature and rate of heating and recently of pressure under inert gases and hydrogen. In particular, the rates of formation and the yields of liquid and gaseous products and the alteration of the solid matter have been examined under pressures ranging from 1 to 100 bar and at rates of heating between 0.05 and 1 000 K/s. It is shown how product formation can be controlled by these parameters and how the experimental data can be applied to reactor design. 相似文献
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B. ÖZÜM M. OĞUZTÖRELI M.P. DUPLESSIS M.N. OGUZTORELI 《Chemical Engineering Communications》2013,200(1-6):287-302
The purpose of this study is to provide a better understanding of reactors for hydroprocessing of liquid-solid mixtures, and to assist in the design and scale-up of large scale reactors from the information obtained from small scale experimental units. The paper describes a linear, isothermal, cocurrent upflow tubular reactor model with axial dispersion. The model is applied to coal liquefaction, assuming that the complex liquefaction kinetics can be represented by five lumped components-six first order reactions, and that the three phase (coal-solvent-gas) flow can be approximated by a two phase (slurry-gas)flow. 相似文献
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zü m M. O uzt reli M.P. Duplessis M.N. Oguztoreli 《Chemical Engineering Communications》1986,44(1):287-302
The purpose of this study is to provide a better understanding of reactors for hydroprocessing of liquid-solid mixtures, and to assist in the design and scale-up of large scale reactors from the information obtained from small scale experimental units. The paper describes a linear, isothermal, cocurrent upflow tubular reactor model with axial dispersion. The model is applied to coal liquefaction, assuming that the complex liquefaction kinetics can be represented by five lumped components-six first order reactions, and that the three phase (coal-solvent-gas) flow can be approximated by a two phase (slurry-gas)flow. 相似文献
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多相光催化反应器数学模型研究进展 总被引:2,自引:0,他引:2
本文介绍了当前多相光催化反应体系中反应动力学模型以及反应器数模研究领域内的主要方法及成果。反应动力学方面依据反应机理和动力学方程进行了说明 ;反应器模型则按学术团体各自不同的研究思路及方法分别概述 ,并依照反应器内部的各相的情况作了分类 ,扼要介绍了辐射能分布方程。对未来此领域的研究方向作了展望。 相似文献
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《Fuel》1986,65(3):346-353
The change of vitrain and durain particles from three high volatile bituminous coals pyrolysed in a wire net apparatus has been filmed with a high speed camera. Results are given on swelling kinetics and plasticity data for a particle of size up to 1 mm, with pressures up to 10 M Pa of hydrogen and rates of heating, 55–900 K s−1 in a helium atmosphere. Also, a correlation between swelling and tar formation is established, which can be used for predicting the change of coal particles in coal conversion reactors. 相似文献