气流床干煤粉气化的技术进展

发展气流床气化技术是中国能源安全和可持续发展的需要。简述了气流床干煤粉气化技术的应用状况和研究进展,分析了干煤粉气化的技术优势和存在的问题,并提出一些改进建议。     

整体煤气化燃气-蒸汽联合循环气化单元模拟

基于化学平衡 ,建立了气流床干煤粉气化的数学模型 .模型计算结果与工业结果基本吻合 ,表明对于气流床干煤粉气化这样的高温反应过程 ,可以用化学平衡的方法近似模拟 .通过分析工艺条件对气化结果的影响 ,发现蒸汽煤比和氧煤比起着调节原煤热值在化学能和物理显热之间的分配的作用 .在联合循环发电 ,可以通过蒸汽煤比和氧煤比的改变 ,调节燃气轮机与蒸汽轮机之间的能量分配关系 .     

现代煤气化技术发展趋势及应用综述

现代煤气化技术是现代煤化工装置中的重要一环,涉及整个煤化工装置的正常运行。本文分别介绍了中国市场各种现代煤气化工艺应用现状,叙述汇总了其工艺特点、应用参数、市场数据等。包括第一类气流床加压气化工艺,又可分为干法煤粉加压气化工艺和湿法水煤浆加压气化工艺。干法气化代表性工艺包括Shell炉干煤粉气化、GSP炉干煤粉气化、HT-LZ航天炉干煤粉气化、五环炉(宁煤炉)干煤粉气化、二段加压气流床粉煤气化、科林炉(CCG)干煤粉气化、东方炉干煤粉气化。湿法气化代表性工艺包括 GE水煤浆加压气化、四喷嘴水煤浆加压气化、多元料浆加压气化、熔渣-非熔渣分级加压气化(改进型为清华炉)、E-gas(Destec)水煤浆气化。第二类流化床粉煤加压气化工艺,主要有代表性工艺包括U-gas灰熔聚流化床粉煤气化、SES褐煤流化床气化、灰熔聚常压气化(CAGG).第三类固定床碎煤加压气化,主要有代表性工艺包括鲁奇褐煤加压气化、碎煤移动床加压气化和BGL碎煤加压气化等。文章指出应认识到煤气化技术的重要性,把引进国外先进煤气化技术理念与具有自主知识产权的现代煤化工气化技术有机结合起来。     

常压粉煤气流床气化装置及试验系统设计与试验验证

为研究粉煤气流床气化过程中的关键技术,优化气流床设计,实现粉煤高效清洁利用,设计了一套常压粉煤气流床气化装置试验系统,该系统包括输粉系统、开工燃烧系统、一体化试验装置、火炬系统、配气系统、水系统、试验台架、测量控制系统、通讯安防系统等。根据试验装置和系统特点,设计了试验流程,开展了试验研究。试验结果表明,该常压粉煤气流床气化装置及试验系统运行安全、稳定、可靠,兼容性强,可为大规模干煤粉气流床气化项目提供参考。     

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干煤粉加压气化装置的操作具有一定的指导意义。     

大型干煤粉气流床气化技术国内应用与展望

煤气化装置是煤化工的核心工段,直接影响着整个装置单元的稳定操作运行。介绍了国内外大型干煤粉气流床加压气化技术工艺流程、特点、应用参数以及在中国市场的应用现状。粉煤加压气化包括Shell炉、GSP炉、Prenflo炉、CCG炉以及国内的航天炉、神宁炉、东方炉、二段加压气流床粉煤加压气化炉。综述了上述气流床煤气化技术的特点及应用现状,并展望了气流床加压技术的应用趋势。     

干法进料气流床煤气化技术的现状与发展

煤气化按煤的粒度和气化炉内的气体流速等可分为固定床、流化床、气流床3种。其中干煤粉气流床加压气化具有易大规模化、煤种适应范围广、碳转化率高等特点,近年来得到大规模的应用。详细介绍了以干煤粉为原料的Shell、Prenflo、Simens GSP和西安热工院的两段式气化技术。     

干煤粉气流床制工业燃气气化过程数值模拟

基于Aspen Plus软件,应用Gibbs自由能最小化方法,建立数学模型,对干煤粉气流床气化制工业燃气过程进行数值模拟。模拟计算结果表明,此模型可以比较准确地预测干煤粉气流床气化炉的出口气体成分。基于此模型,分别考察了氧煤比、蒸汽煤比对气化温度和有效气产量的影响,并确定出神华煤种合理的氧煤比为0.8和蒸汽煤比为0.1。     

干煤粉加压气化技术的现状和进展

干法进料的气流床煤气化技术是当今国际上最先进的煤气化技术之一,与水煤浆气化技术相比,具有煤种适应性广、原料消耗低、碳转化率高、冷煤气效率高等优势,有更强的市场竞争力。为了加强对干煤粉加压气化技术的基础研究和应用推广,研究了干煤粉气化炉、气流输送过程、合成气净化系统及其配套工艺,分析了干煤粉气化炉在应用中存在的问题,并针对这些问题提出了解决的思路。概述了国内外大型粉煤气流床气化技术发展的主要情况,分析了干法进料气流床煤气化技术中存在的问题与采取的技术途径。     

典型的干煤粉与水煤浆加压气流床煤气化技术的分析比较与选择

简要介绍了干煤粉与水煤浆2种不同加压气流床煤气化技术的发展现状、技术特点及应用情况,并针对2种典型的干煤粉气流床气化技术以及2种典型的水煤浆气流床煤气化技术进行了综合比较和分析。在此基础上,针对当前大型煤化工项目加压气流床煤气化技术的选择,从原料煤种的适应性、目标产品种类及特点、煤气化装置投资、技术成熟性和可靠性以及项目综合能效等多方面进行了分析和讨论,以期为当前的煤化工项目选择最合适的加压气流床煤气化技术提供参考。最后,对加压气流床煤气化技术的发展趋势进行了展望。     

Thermodynamic modeling of the water-gas shift reaction in supercritical water for hydrogen production

In this study, a computational model is developed for the estimation of the equilibrium composition of WGSR (water gas shift reaction) based on the stoichiometric and nonstoichiometric thermodynamic approaches. The model employs the Peng–Robinson equation of state (PR-EoS) formulation and the Gibbs free energy minimization. A Matlab computer program is developed for the numerical solution of a highly nonlinear equation of systems satisfying thermodynamic constraints. Molar fractions of each species are determined for different physical conditions using the proposed computational model and the computer code. Comparisons of model predictions with previous results show that molar fractions can be computed accurately using the present computational algorithm. On the basis of the numerical tests, a novel empirical expression is proposed to determine the hydrogen yield for energy considerations.     

Matlab在微生物生长预测模型中的应用

利用Matlab构建了一个微生物仿真系统,在形成仿真函数库的基础上,结合VC 6.0编程软件,最终开发出独立于Matlab的软件系统.     

基于改进双种群遗传算法的复合材料层合板铺层优化设计

针对复合材料层合板铺层优化设计过程中易出现的算法早熟及收敛慢的问题,结合多种群遗传算法和自适应遗传算法,提出一种引入自适应算子的改进双种群遗传算法。在算法过程中以对称复合材料层合板为例进行验证,通过Patran建立有限元初始模型,采用Matlab编写遗传算法主程序及数据传递程序,实现对Nastran的输入输出文件的读写,并在以Tsai-Wu准则为基础确立的适应度函数下,对复合材料层合板的铺层顺序进行优化。对比传统遗传算法,结果表明该改进算法能够明显提高优化效率,并能够有效收敛于全局最优解,对解决复合材料结构优化设计问题有一定的指导意义。     

闭式冷却塔的计算模拟

分析了闭式冷却塔的传热传质机理,建立了其数学计算模型,求解沿塔高度方向的温度分布,采用一维和二维模型对比分析,一维模型每排管为一个单元,二维模型每排管分别划分4个、10个单元,利用Matlab编写圆管型闭式冷却塔程序,与Hasan的结果对比,管内冷却水沿塔高度的温度分布采用二维模型每排管划分4个单元和10个单元相比相差较小,二维模型比一维模型的管内冷却水温度分布更接近Hasan的结果;按二维模型每排管划分10个单元,采用Matlab编写圆管模拟程序,采用分段计算的方法预测冷却水出口水温,与实验结果相比,一致性较好。该模型可用来预测不同流速和不同室外空气状态下闭式冷却塔的出口水温和喷淋水水温。     

溶液再生器传热传质过程的数值模拟

根据湿空气和溶液热质交换的基本理论,建立了叉流溶液再生器的传热传质数学模型,并将该模型简化,得出空气和溶液的质量、能量控制方程。根据数值求解的方法,对方程进行离散简化,利用Matlab语言编程模拟计算。将模拟结果和实验结果进行了比较,结果表明本模型可靠。     

DEVELOPMENT AND VALIDATION OF A PROCESS SIMULATOR FOR DRYING SUBBITUMINOUS COAL

Drying subbituminous coal has never been practiced commercially. The commercial dryers built to date have been designed for drying surface moisture in conjunction with upstream coal preparation facilities. This type of drying is mainly controlled by input energy and the basis of the design is an energy balance. In drying inherent moisture from subbituminous coal, the thermal conductivity of the coal and the diffusion of molecular water within coal particles impose limitations on the process conditions. Energy input and solids residence time in the dryer have to be controlled properly for simultaneously balancing the heat and mass transfer within the coal particles. Improper control of either parameter can cause fires and explosions during the key steps of the drying process—drying and cooling

In parallel to the Anaconda coal drying pilot plant program, a cross-flow, fluid-bed coal drying/cooling process simulator was developed for: (1) understanding the drying phenomena on an individual particle basis; (2) analyzing potential risks and safety limits, and (3) designing the Anaconda pilot plant program

The development of the process simulator was based on both first principles and laboratory data and can be divided into two phases:

1 Development of a semi-mechanistic drying model for Powder River Basin subbituminous coal employing an analytical solution of the diffusion equation

2.Formulation of a fluid-bed cross-bed cross-flow dryer/cooler simulator employing simultaneous heat and mass transfer

This model was validated against process variables data taken on a 4 tph pilot plant. An operable range, or process envelope, has been developed through the pilot plant experience and the process simulation study. Based on the model predictions, an uncertainly range was defined in the design recommendations of a pioneer coal drying plant in scale-up.     

生物质流化床空气-水蒸气气化模型研究

根据流化床反应器特点,结合生物质气化动力学反应机理,建立了生物质在流化床内气化的等温稳态、一维二相动力学模型。该模型所做的主要假定如下:流化床分为气泡相和乳相,在气泡相和乳相内均存在化学反应,考虑二相内的轴向气体扩散,生物质热解过程瞬时完成,主要考虑焦碳以及CO,CO2,H2,H2O,CH4等在流化床内发生的8个主要化学反应。数学模型属于常微分方程组边值问题,利用数值计算软件M atlab7.0进行编程求解。以木粉为原料,将模型结果与实验结果进行了对比,模拟结果与试验数据符合良好,在一定程度上证明了模型的有效性和可靠性。     

蒙特卡洛优化法在炼焦配煤中的应用

应用蒙特卡洛优化法配煤，只需做一定量的试验就可确定目标函数或约束条件函数中的某些系数，并根据需要，建立数学模型，编制程序，求出最优解。     

Particle population model for a fluidized bed with attrition

For a steady-state fluidized process, a population model for particle mixtures undergoing both attrition and reaction is developed. Populations of different materials affect each other through ways such as attrition. The evolution of the attrited fines is more realistically assessed so that the differential solid balance is consistent with the overall mass balance. The possible effects of fines on the attrition and reaction are considered too. Effects of several input and operational conditions on the process performance are discussed and demonstrated by a simulating program. Many particle population models in the literature can be seen as special cases of the present model. The model represents a more realistic approach to the simulation of the fluidized-bed process.     

Programmed cooling of batch crystallizers

An analysis of the programmed cooling of batch crystallizers, starting with the solution of the momentum equations of the population balance, is presented. Based on a general solution, conditions are discussed leading to limiting equations which had been published earlier. The model described in this paper determines the optimum cooling curve for a batch crystallizer with an arbitrary seeding and nucleation ratio, hence a more detailed analysis of the physical conditions of the process and a better comparison of the theory with experiment are possible. Kinetic data of crystallization can also be obtained from batch experiments.