基于Aspen Plus建立喷流床煤气化炉模型

引　言当前 ,环境污染和液体燃料短缺已经成为制约我国经济持续高速和安全发展的瓶颈问题 .通过煤的大规模、综合、清洁、高效利用来解决未来对能源尤其是对液体燃料的需求 ,已经成为我国政府和科学界的共识[1] .在未来的能源结构中 ,以煤气化为基础的新型能源系统无疑将扮演越来越重要的角色[2 ] .因此 ,深入开展以煤气化为基础的新型能源系统尤其是多联产系统的研究十分必要 .鉴于煤气化能源系统中涉及大量横跨动力过程和化工过程的特殊设备 ,本文选择Aspen作为工具软件开展研究 ,其中的一个重要任务就是建立能在Aspen中使用的特殊设备模…     

气流床煤气化的Aspen Plus建模：平衡模型和动力学模型

基于Aspen Plus软件建立了GE气流床煤气化的平衡模型和动力学模型,计算了气化的煤气组成和碳转化率。模型分为热解、气化和气液分离三个阶段。其中,气化阶段又分为初步气化和气化重整,从而获得气化产物在恒定温度下的分布。平衡模型的气化阶段使用了吉布斯反应器RGIBBS,基于吉布斯自由能最小化原理对体系内的气化产物进行计算;动力学模型的气化阶段使用了全混流反应器RCSTR,基于煤气化反应的动力学机理对体系内的气化产物进行计算。模拟值与GE气化炉的实际工程数据进行了对比,结果表明,平衡模型可在一定程度上反映气化结果的变化趋势,但预测结果的准确性有所欠缺,而基于气化反应机理建立的动力学模型能很好地预测GE气化炉的气化结果。对动力学模型中的全混流反应器进行反应时间设定,可以对GE气化炉生产提供一定的指导,结果表明：反应停留时间为3.5s时就可以达到很好的气化效果。温度是影响气化反应速率及产物分布的重要因素,利用煤气化的动力学模型模拟了气化温度对气体组成及碳转化率的影响,结果表明：随着气化温度的升高,CO含量逐渐增加,H₂含量基本不变,CO₂含量逐渐减小,碳转化率逐渐升高。     

孔隙尺寸、盐度和气体组分对水合物相平衡的影响(英文)

An experimental device was set up to study the hydrate formation conditions. Effects of pore size, salinity, and gas composition on the formation and dissociation of hydrates were investigated. The result indicates that the induction time for the formation of hydrates in porous media is shorter than that in pure water. The decrease in pore size, by decreasing the size of glass beads, increases the equilibrium pressure when the salinity and temperature are kept constant. In addition, higher salinity causes higher equilibrium pressure when the pore size and temperature are kept constant. It is found that the effects of pore size and salinity on the hydrate equilibrium are quite different. At lower methane concentration, the hydrate equilibrium is achieved at lower pressure and higher temperature.     

UNIFAC模型法计算含己内酰胺体系的相平衡(英文)

An extended liquid-liquid equilibrium (LLE) UNIFAC model is proposed to describe phase equilibria of mixtures containing caprolactam. In this model, caprolactam is introduced as a new group. New group interaction parameters are calibrated from 156 sets of liquid-liquid equilibrium data. The present model gives satisfactory correlation and prediction in liquid-liquid equilibrium, including quaternary systems containing the mixed solvent of an alcohol and an alkane. The model can be applied to predict caprolactam solubility in water and benzene accurately. Freezing point and vapor-liquid equilibrium of binary systems containing caprolactam are also predicted with the extended LLE UNIFAC model. Satisfactory prediction results are obtained.     

ZL50活性炭吸附脱除二氧化硫的吸附动力学模型(英文)

A semi-empirical adsorption kinetic model was proposed with the time compensation method to describe the chemisorption of SO2 in flue gas by carbon adsorbents for flue gas purification. The change in adsorption capacity and adsorption rate with time at different water vapor concentrations and different SO2 concentrations was studied. The model was in good agreement with experimental data. The surface reaction was probably the rate controlling step in the early stage for SO2 adsorption by ZL50 activated carbon. The parameters m and n in the nth order adsorption kinetic model were related to the magnitude of the time compensation and adsorption driving force, respectively. The change of parameter n with water vapor concentrations and sulfur dioxide concentrations was studied and some physical implications were given. The sum of square errors was less than 1.0 and the average absolute percentage deviations ranged from 0.5 to 3.2. The kinetic model was compared with other models in the literature.     

竹制活性炭处理酸性染料废水吸附等温线模型的误差分析(英文)

High surface area activated carbons were produced by thermal activation of waste bamboo scaffolding with phosphoric acid.Single component equilibrium dye adsorption was conducted on the carbons produced and compared with a commercially available carbon.Two acid dyes with different molecular sizes,namely Acid Yellow 117(AY117) and Acid Blue 25(AB25),were used to evaluate the adsorption capacity of the produced carbons.It was found that the dye with smaller molecular size,AB 25,was readily adsorbed onto the produced carbon,nearly three times higher than a commercially available carbon,while the larger size dye,AY117,showed little adsorption.The experimental data were analyzed using isotherm equations including Langmuir,Freundlich,Tempkin,Toth,Redlich-Peterson and Sips equations.The equilibrium data were then analyzed using five different non-linear error analysis methods.     

利用~1HNMR和共沸点推算醇/烃体系的汽液平衡数据(英文)

With the energy parameters obtained from 1H nuclear magnetic resonance (NMR) chemical shifts data by local composition model and coupled with azeotropic point, the low-pressure vapor-liquid equilibrium is satisfactorily predicted for alcohol + hexane, alcohol + cyclohexane, and alcohol + benzene binary systems at different temperatures. The relationship between the spectroscopic information and thermodynamic property is presented.     

基于模型预测控制的部分分散控制系统设计(英文)

An expansion procedure to design partially decentralized controllers via model predictive control is proposed in this paper. Partially decentralized control is a control structure that lies between a fully decentralized structure and a fully centralized one, and has the advantage of achieving comparable performance as a fully centralized controller but with simpler structure. The proposed method follows the expansion method proposed in a previous paper where internal model control (IMC) was used to design controllers for non-square subsystems. The method requires computing the pseudo-inverse of a non-square matrix via pseudo-inverse factors. Instead, the proposed method uses dynamic matrix control (DMC) to design PID controllers for non-square subsystems without using additional factors. The effectiveness of the proposed method is demonstrated on several chemical examples. Simulation results show that the proposed method is simple and can achieve better performance.     

非理想多组分混合物中质量传递过程基于Maxwell-Stefan扩散理论的建模及数值分析(英文)

The Intalox metal tower packing was used to simulate an industrial relevant extractive distillation column for purifying azeotropic multicomponent mixture.In order to explain the inconsistencies in the modeling of transfer process in nonideal multicomponent distillation column,a method was developed with equilibrium stage models(EQ)and non-equilibrium model(NEQ)incorporated with Maxwell-Stefan diffusion equations in the framework of AspenONE  simulator.Dortmund Modified UNIFAC(UNIFAC-DMD)thermodynamic model was employed to estimate activity coefficients.In addition,to understand the reason for the diffusion against driving force and the different results by EQ and NEQ models,explicit investigations were made on diffusion coefficients, component Murphree efficiency and mass transfer coefficients.The results provide valuable information for basic design and applications associated with extractive distillation.     

旋转填充床中沉淀过程的模型及实验验证(英文)

A mixing-precipitation model based on the modified coalescence-redispersion model was presented to describe the flow, mixing, nucleation and growth in a rotating packed bed (RPB). The model was coupled with population balance, mass balance and crystallization kinetics. It predicted well the influence of coalescence probability, which represents the mixing intensity among drop-lets, on the particle number density, supersaturation and mean particle size of the produced precipitates. The effects of the radial thickness of packing, liquid flow rate and rotating speed on the product particle size were also investigated. The results indicate that the needed radial length of packing is short for sparingly soluble substance precipitation (about 40-50 mm in this work), and the mean particle size of precipitates decreases with the increase of rotating speed and liquid flow rate, respectively. The validity of this model was verified by experiment on BaSO4 precipitation in RPB.     

基于Aspen Plus的水煤浆气化模拟

文章以过程模拟软件Aspen Plus为工具,建立了以纯氧为气化剂的气流床煤气化的数学模型,模拟计算了Texaco气化炉的制气过程;并利用该模型模拟研究了氧煤比和水煤浆浓度对煤气化指标的影响。结果表明:水煤浆浓度和氧煤比是影响水煤浆气化过程和出口煤气成分的主要因素,同时提出了提高出口煤气有效成分(CO+H2)的措施。     

固定床煤气化过程的数学模型

根据气化原料与氧气、二氧化碳和水蒸气反应的动力学参数,在三传一反的基础上,建立了固定床煤气化过程的数学模型;对加压气化炉、水煤气炉等进行了模拟计算与分析。     

气流床气化炉操作温度的探讨

通过探讨气化炉操作温度的影响因素,建议依据气化炉型、煤质、目标产物煤气组成等主要因素,建立气流床气化炉操作温度评价模型,为气化炉运行提供直接的适宜的操作温度,旨在延长气化炉的运行周期和使用寿命,提高气化装置运行的经济性。     

粉煤加压气流床气化炉内化学平衡分析

用解析的方法，详细计算了粉煤加压气流床气化装置煤气组成与操作温度的关系，并对各种操作变量对气体成分及析炭副反应的影响做了量化分析，对我国已经引进或正要引进的千煤粉加压气化装置的操作具有一定的指导意义。     

一种用于煤气化过程监控的简便平衡组分估算方法

针对气流床气化炉的过程监控开发了一种计算气化产物平衡组成的简易估算方法。该算法主要包含一个需迭代求解的非线性方程,可求解9种可在线监控的气体组分。该算法用5种不同工业工况在水煤浆进料和干煤粉进料气化炉上进行了验证,结果表明:与基于Gibbs自由能最小化算法相比,该算法收敛性好、计算强度小且内存占有率低,计算准度符合过程监控的需要。利用本算法分析了气流床气化炉适宜作调控气化炉运行状况的气体组分选择方案:对操作在1 300~1 450℃范围内的气化炉适宜采用H_2与CH_4作为监测变量;而对操作在更高温的气化炉适宜采用有效气含量作为监测变量。     

神木煤粉加压气流床气化中试试验研究

介绍了36t/d加压气流床气化中试装置主要设备、工艺流程及工艺条件的选择,并给出采用神木煤在气化压力3.0MPa、干粉煤投量1t/h条件下取得的主要试验数据:碳转化率98.9%,冷煤气效率83.2%,并给出相应的氧、煤耗,试验结果基本达到预期目的。     

加压气流床煤气化工艺的发展现状及存在问题

介绍了国内外开发的主要加压气流床煤气化工艺的发展现状,包括德士古气化、E-Gas气化、壳牌和普兰福气化、GSP气化、多喷嘴水煤浆加压气流床气化、两段喷干煤粉的气流床加压气化等,列举出这些气化技术中目前存在的主要问题,并对其解决途径进行了探讨,提出了一些建议。     

双高煤的新型气流床气化技术开发的探讨

现有的气流床气化技术均为高温熔渣气化技术,使国内资源丰富的双高煤无法利用.通过气化机理分析认为,双高煤采用非熔渣气化、固态排灰的操作方式是可行的.针对这种新型气流床气化技术在开发过程中可能存在的主要问题进行了探讨,并提出了相应的对策及建议.     

气流床气化低阶煤的脱水提质预处理

褐煤、长焰煤等高含水低阶煤,无法直接用于水煤浆和粉煤气流床气化。概述了目前国内外开发的低阶煤低温蒸发脱水和干燥提质,低阶煤液态脱水提质,转化提质等方法。适用于粉煤气化的预处理关键是脱水;适用于水煤浆气化的预处理关键是提质,以提高煤表面结构的疏水性,降低干燥后煤的水分回吸平衡,制备高浓度煤浆。     

对有关气流床加压煤气化工艺最近一些发展动向的看法

对加压气流床气化技术最近的各种发展动向进行了总结、分析,认为有些发展有明显的效果,但有些发展的实际效果还值得讨论。同时对其他非气流床煤气化工艺进行了分析,认为在选择合适的气化工艺时应根据用户的实际情况,因煤制宜、因目的产品制宜,合理选择。