带惰性载热固体煤气化流化床的气化行为

引言煤气化是生产清洁燃料或原料的重要工业方法之一．在一般流化床或移动床煤气化反应器中,碳与水蒸气的气化和碳与氧的燃烧反应同时发生．如果希望使用这类气化器生产高热值或富氢的煤气,则需要在高温和高压下提供富氧气体,而这种方法还存在很多实践上的问题．最近日本鹿儿岛大学开发了一种如图1所示的新型煤气化器,可以很方便地通过催化煤气化产生富含H_2和CO的煤气．在这种新型气化器中,气化和燃烧是分别在两个不同反应室内进行的,气化室中所需的热能由来自燃烧室的惰性固体载热体提供.作为这种新型煤气化反应器研究的一部分,…     

煤加压气化技术的研究开发

简要介绍了煤科总院北京煤化工研究分院在加压固定床气化—包括Φ650mm中试和Φ100mm小试技术,Φ100mm和Φ300mm加压流化床气化技术等方面的研究和开发情况,重点介绍了典型中国煤种在上述固定床和流化床气化炉试烧时的气化特性。指出做为国内唯一的固定床加压气化小试装置和少有的加压流化床气化小试装置,今后将在煤种气化特性评价、煤化工多联产规划等方面发挥积极作用,同时简要阐述了加压气化技术的发展前景。     

PERFORMANCE OF A PRESSURIZED TWO-STAGE FLUIDIZED GASIFICATION PROCESS FOR PRODUCTION OF LOW-BTU GAS FROM COAL CHAR

A two-stage pressurized fluidized-bed gasification process has been developed to produce low-heating value gases from coal char. The reactor was 0.075 m id. and 1.4 m long, and gasification experiments were conducted under pressures up to 790 kPa and at temperatures up to 1323 K. A partition disc was used to divide the fluidized bed into two stages, using the first stage as a partial combuster and gasifier and the second stage as a gasifier. The disc was designed to control compositions of coal char particles in both stages so that the heat required for the endothermic gasification reaction in the second stage can be provided by the heat of combustion in the first

For conditions examined here, the disc with an opening ratio of 40° was found to give optimum distribution of the char particles in both stages without ash agglomeration. It was also shown that all oxygen gas was completely consumed within the first stage

The heating value of the product gas increased with the char feed rale. However, there may be an oplimum Teed ratio of char and sand-particles since the higher char feed rate causes more frequent ash agglomeration as well as less carbon conversion     

新型水煤浆气化技术的开发及其应用

通过大型冷模和小型热模研究新型（多喷嘴对置）水煤浆气化炉,介绍了中试结果及其与Texaco水煤浆气化技术的比较,并简述了推广应用前景。     

Hydrierende Vergasung von Kohle – Neuere Betriebsergebnisse

Hydrogasification of coal – recent operational results . The Rheinische Braunkohlenwerke AG has built and has been operating a semi-technical pilot plant for hydrogasification of coal in a fluidized bed. The objective is to develop a coal gasification process with hydrogen for producing directly substitute natural gas. Between 1976 and 1981, the semitechnical pilot plant having a capacity of 100 kg C/h was operated for about 22,900 h under test conditions, more than 9,500 h of which were under gasification conditions. During this time, approximately 1,400 metric tons of dry coal were gasified. The longest coherent operational phase under gasification conditions was 748 h in which 86.4 metric tons of dry lignite were gasified. Carbon gasification rates up to 82% and methane contents in the dry raw gas (free of N₂) up to 48 vol.-% were obtained. A detailed evaluation of the test results provided information on the influence of additional parameters on the efficiency dates of the gasifier and a considerable refining of the results obtained previously. Moreover, several components were tested for which no operational experience had previously been gained; these were newly developed devices, e. g. the inclined tube for feeding coal into the fluidized bed. Within the framework of scale-up work to large-scale coal gasification plants, a pilot plant having a capacity of approximately 6 t C/h will be commissioned in late 1982.     

新型(多喷嘴对置)水煤浆气化炉的开发

通过大型冷模和小型热模试验开发新型（多喷嘴对置）水煤浆气化炉,介绍了中试结果及其与德士古水煤浆气化技术的比较,并阐述了新型水煤浆气化炉的技术优势,结果表明,多喷嘴对置气化技术优于引进的德士古技术。     

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。     

水煤浆加压气化煤种评价模型

本模型是按照动力学及热力学的原理,建立在水煤浆加压气化实验室试验、中间试验和工业化生产操作基础上的经验模型。能用于工业化生产装置在设计和生产过程中煤种的选择、煤种的更换和气化炉工艺操作条件的优化,并为新建水煤浆气化装置的ＰＤＰ编制提供基础数据和依据。模型计算结果希望能取代煤种试烧。     

多喷嘴对置水煤浆气化炉的开发与应用

介绍多喷嘴对置水煤浆气化炉的实验室研究及中试情况,并与Texaco水煤浆气化技术进行了比较,结果表明,多喷嘴对置气化技术优于Texaco技术。     

Performance of a coal gasification pilot plant with hot fuel gas desulfurization

A coal gasification pilot plant operation with hot fuel gas desulfurization (HGD) was performed taking two coals (Indonesian ABK and MSJ) that differ in their carbon and sulfur contents. A dry-feeding entrained-bed type gasifier was used for gasification with oxygen and capable of operating at 30 bar pressure and 1,550 °C. The HGD unit consisted of a transport desulfurizer, a bubbling regenerator and a multi-cyclone. Attention was focused on attaining high carbon conversion and cold gas efficiency in the entrained bed reactor and the sulfur removal efficiency of the hot fuel gas desulfurization unit. The optimum conditions for achieving high performance of the operation are reported.     

GSP气化炉内多相湍流反应流动模拟研究

采用涡耗散概念(EDC)模型,对某化工厂的GSP气化炉内多相反应流场进行了数值模拟研究.计算中采用Realizable k-ε湍流模型对雷诺平均后的N-S方程进行封闭;采用离散相随机轨道模型来模拟气化炉内煤颗粒的弥散运动;采用P1模型对燃烧的辐射传热进行模拟.计算结果表明:气化炉内为强旋射流流场,颗粒在气化炉顶部回流区...     

鼓泡流化床内高灰煤气化过程的颗粒尺度特性研究

基于多相流体质点网格方法(MP-PIC)对高灰煤在三维鼓泡流化床气化过程进行了数值模拟研究。在欧拉-拉格朗日框架下将气相和固相分别视作连续介质和离散相处理。首先,将模拟得到的出口处气体组分结果与实验数据进行对比,实验数据与模拟结果具有良好的一致性。其次,研究了煤颗粒在气化炉内的温度、传热系数、速度和停留时间,从颗粒尺度揭示了鼓泡流化床气化炉内的颗粒分布特性和气固流动特征。结果表明:在气化炉入口附近煤颗粒与床层温差最大,传热系数最大;由于流化床内强非线性的气固流动,床中煤温度和传热系数的空间分布不均匀;煤颗粒和床料的瞬时速度具有稳定的波动幅度,其中垂直方向速度波动最明显,且煤颗粒的瞬时速度比床料的瞬时速度略大;由于颗粒间的剧烈碰撞,延长了煤颗粒停留时间。此外,对鼓泡流化床中煤气化过程颗粒尺度的研究,有助于深入了解固体颗粒的流动行为以及气固相相互作用特性,对鼓泡流化床反应器的设计优化具有重要意义。     

灰熔聚流化床粉煤气化技术加压大型化研发新进展

灰熔聚流化床粉煤气化技术历经20余年的研发和工程化放大,低压气化技术已日趋成熟,并用于氮肥企业原料气改造和新建甲醇合成厂。该气化技术可使用不同灰含量和灰熔融性温度的煤,过程效率也较高,符合我国资源特点。为此在山西省发展和改革委员会的支持下,中科院山西煤化所和山西晋煤集团合作成立的“山西省粉煤气化工程研究中心”正在建设3.0MPa加压灰熔聚流化床粉煤气化中试平台,2006年年底已建成,预计于2007年3月进行加压气化试验,2007年完成加压灰熔聚流化床煤气化工业装置设计软件包的编制,形成具有我国自主知识产权、适应中国煤炭特点的大规模加压灰熔聚流化床粉煤气化技术。本文介绍了灰熔聚流化床粉煤气化过程,指出它的优点、缺点、适用范围、技术现状和发展方向,并对加压灰熔聚气化中试技术进行了简介。     

烟煤水煤气气化炉运行的可行性分析

烟煤水煤气气化炉是将双火层煤气发生炉的气化原理用于水煤气气化的一种炉型。介绍了双火层气化炉的炉型规格、供气形式和半水煤气组成;从煤气中CO2和CH4含量、气化炉反应温度、蒸汽量的调整等方面分析了烟煤水煤气气化炉生产运行的可行性;介绍了烟煤水煤气气化炉的结构形式和工艺流程;计算了原料煤成本的经济效益,结果表明,4万t/a合成氨装置每年可节约原料煤费用1160万元,20万t/a甲醇装置每年可节约原料煤费用6960万元。     

Linking laboratory data with pilot scale entrained flow coal gasification performance. Part 1: Laboratory characterisation

Pilot scale measurements play an important role in our understanding of the coal gasification process. To gain the most practical benefits from such testing it is important to have a good understanding of the fundamental processes that influence coal behaviour under industrial conditions. In this paper, a suite of Australian coals was characterised in detail at the laboratory scale and preliminary assessments made of their likely performance under practical entrained flow conditions. The same coals were then tested using a 5 MW_th pilot-scale entrained flow gasifier in Part 2. The resulting gasification dataset for a suite of coals at both laboratory and pilot scale provides a unique opportunity to quantify the links between laboratory gasification measurements and coal gasification behaviour under realistic conditions. This paper presents a characterisation of four Australian thermal coals in terms of their slag formation and flow behaviour, coal devolatilisation and reactivity properties, and their gasification conversion behaviour. This work provides the basis for a relative assessment of their potential for use in entrained flow gasification, and identifies possible performance issues which may need consideration for use in larger-scale gasification systems. The second paper discusses the pilot-scale gasification behaviour of these coals, and relates those data with those presented here.     

Carbon particle type characterization of the carbon behaviour impacting on a commercial-scale Sasol-Lurgi FBDB gasifier

Char-form analysis, whilst not yet an ISO standard, is a relatively common characterization method applied to pulverized coal samples used by power utilities globally. Fixed-bed gasification coal feeds differ from pulverized fuel combustion feeds by nature of the initial particle size (+6 mm, −75 mm). Hence it is unlikely that combustion char morphological characterization schemes can be directly applied to fixed-bed gasifier chars. In this study, a unique carbon particle type analysis was developed to characterize the physical (and inferred chemical) changes occurring in the particles during gasification based on coal petrography and combustion char morphology. A range of samples sequentially sampled from a quenched commercial-scale Sasol-Lurgi fixed-bed dry-bottom (FBDB) Gasifier were thus analysed.It was determined that maceral type (specifically vitrinite and inertinite) plays a pivotal role in the changes experienced by carbon particles when exposed to increasing temperature within the gasifier. Whole vitrinite particles and vitrinite bands within particles devolatilized first, followed at higher temperatures by reactive inertinite types. By the end of the pyrolysis zone, all the coal particles were converted to char, becoming consumed in the oxidation/combustion zone as the charge further descended within the gasifier.The carbon particle type results showed that both the porous and carbominerite char types follow similar burn-out profiles. These char types formed in the slower pyrolysis region within the pyrolysis zone, increasing to around 10% by volume within the reduction zone, where 53% carbon conversion occurred. Both of these char forms were consumed by the time the charge reached the ash-grate at the base of the reactor, and therefore did not contribute to the carbon loss in the ash discharge. It would appear as if the dense char and intermediate char types are responsible for the few percent carbon loss that is consistently obtained at the gasification operations.The carbon particle type analysis developed for coarse coal to the gasification process was shown to provide a significant insight into the behaviour of the carbon particles during gasification, both as a stand alone analysis and in conjunction with the other chemical and physical analyses performed on the fixed-bed gasifier samples.     

Co-gasification of coal and wood in a dual fluidized bed gasifier

In the last decade the reduction of CO₂ emissions from fossil fuels became a worldwide topic. Co-gasification of coal and wood provides an opportunity to combine the advantages of the well-researched usage of fossil fuels such as coal with CO₂-neutral biomass. Gasification itself is a technology with many advantages. The producer gas can be used in many ways; for electric power generation in a gas engine or gas turbine, for Fischer-Tropsch synthesis of liquid fuels and also for production of gaseous products such as synthetic natural gas (bio SNG). Moreover, the use of the producer gas in fuel cells is under investigation. The mixture of coal and wood leads to the opportunity to choose the gas composition as best befits the desired process. Within this study the focus of investigation was of gasification of coal and wood in various ratios and the resulting changes in producer gas composition. Co-gasification of coal and wood leads to linear producer gas composition changes with linear changing load ratios (coal/wood). Hydrogen concentrations rise with increasing coal ratio, while CO concentrations decrease. Due to the lower sulfur and nitrogen content of wood, levels of the impurities NH₃ and H₂S in the producer gas fall with decreasing coal ratio. It is also shown that the majority of sulfur is released in the gasification zone and, therefore, no further cleaning of the flue gas is necessary. All mixture ratios, from 100 energy% to 0 energy% coal, performed well in the 100 kW dual fluidized bed gasifier. Although the gasifier was originally designed for wood, an addition of coal as fuel in industrial sized plants based on the same technology should pose no problems.     

流化床气化中小龙潭褐煤灰结渣行为

为探索小龙潭褐煤流化床气化过程中的煤灰结渣行为,采用化学成分、扫描电镜(SEM)和X射线衍射(XRD)相结合对小龙潭煤气化炉内残留渣块和不同温度热处理后煤灰的成分、形貌和晶相组成进行了表征和对比分析,并对升温过程中煤灰的矿物质演变进行了研究。结果表明:在小龙潭气化过程中流化床气化过程中渣块形成时铁元素发生了明显的富集,小龙潭气化残留渣块和950℃煤灰的微观形貌和晶相组成基本相同。小龙潭褐煤在流化床气化过程中950℃左右生成低熔点共融物钙长石、钙黄长石和铁钙辉石等是引起结渣的主要因素。     

Characterization of unburned carbon present in coarse gasification ash

Depending on the mode of operation and quality of the feed material, discrete unburned carbon particles are evident in coarse gasification ash emanating from a commercial gasifier. Black, partially reacted carbon particles in the size range −13 + 4 mm were randomly hand picked from grab sample following a gasifier shutdown. These particles were classified into three major categories namely: unburned carbon, carbonaceous shale, and “shrinking core” particles. The unburned carbon particles were further macroscopically subdivided into remnant “coal” particles, solid carbon, layered carbon, and porous carbon. The unburned carbon particles were characterized using a petrographic analysis, reflectance analysis, chemical analysis, TGA mass loss curves, pore volume and surface area, and mineral characterization. The carbon particles were compared to the feed coal. The petrographic-based characterization technique as developed for the characterization of coarse unburned carbon particles indicated that remnant coal, devolatilised coal, highly porous isotropic carbon, dense anisotropic carbon, and variations in-between occurred in the coarse gasification ash sample.     

PRENFLO煤气化工艺的开发和应用

介绍了Prenflo煤气化工艺的开发过程,论述了Prenflo中试装置的工艺流程、气化煤种和试验结果;以西班牙Puertollano IGCC电站投煤量为2600t／d的Prenflo煤气化装置为例,总结了Prenflo气化工艺自1988年迄今的商业化运行情况;从气化炉结构、煤气流动方向、氧气纯度和原料粉煤细度等方面对Prenflo和Shell2种煤气化工艺进行了区别和对比。