加压粉煤流化床气化技术试验研究

一套日处理５ｔ煤的加压流化床粉煤气化技术试验装置建成并投入试验运行。进行了５种原料的气化试验。试验采用螺旋和喷嘴两种加料方式。气化炉内的灰团聚与灰选择性分离技术相结合使气化灰渣含灰达９０％,煤气冷凝液中无焦油类物质。气化炉产生的煤气供低热值煤气燃烧试验和燃气轮机叶片磨蚀试验之用。介绍了加压流化床气化的工艺试验内容,煤种试验结果及环境特性数据。连续运行试验基本验证了该加压流化床气化系统的工艺可行性、     

灰熔聚流化床粉煤气化技术研究进展

本文综述了灰熔聚流化床粉煤气化技术的研究进展,“六五”期间完成了直径为0.3m 的全流程运转试验,取得了阶段性成果,“七五”期同完成了直径为1m 的中间试验,该试验结果为建立适合于中国国情的工业装置,提供了处理能力为100t/d 的基础设计依据。     

灰熔聚流化床粉煤气化技术及其工业应用

煤气化是将固态煤转化为气态燃料或原料(CO H2)的过程，由于煤炭的储量丰富，特别是我国等一些国家富煤少油，煤气化技术就变的更加重要。研究开发煤气化工艺，就是要为产业界提供更高效、经济和清洁的气化过程。本在分析先进煤气化过程原理的基础上，特别介绍了由中国科学院山西煤炭化学研究所开发的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，供同行了解。     

循环流化床粉煤气化工艺

本文介绍了循环流化床粉煤气化新工艺及其流程，热态小试验与半工业性试验结果证明该工艺适宜在中型陶瓷厂推广。     

加压流化床粉煤气化技术工业化问题及思考

介绍了开发加压循环流化床粉煤气化技术的必要性、开发背景和市场前景,着重分析了示范装置设计建设过程中的关键技术及其解决措施.     

灰熔聚流化床粉煤气化技术现状及应用前景

随着我国加入WTO的日子一天天临近,据有关部门透露,我国将在2004年取消进口化肥的关税和配额,届时必将有一批国外化肥挤占我国市场,我国氮肥行业将面临新的严峻挑战。目前,我国氮肥产量居世界第一位。在氮肥的生产原料中,天然气、重油、煤(焦)各占一定的份额。由于我国天然气田多分布在中、西部地区,除少数几家处在原料产地的大型合成氨厂原料气价格能维持在0．　6元／m3以外,大多数企业的原料天然气价格在0．　8～1．　0元／m３之间。这样吨氨成本中原料气就在640～８００元左右,在中东地区,加拿大、俄罗斯的天然气价格每m３大…     

灰熔聚流化床粉煤气化工艺

本文介绍了灰熔聚流化床粉煤气化工艺特点及中间试验装置的运行结果，并对推广使用前景做了简述。     

常压循环流化床(CFB)气化技术概况

介绍鲁奇公司的常压循环流化床（CFB）气化技术开发过程，以湿法为例介绍CFB生产合成气的基本流程。该工艺具有原料范围广，系统温度均匀，操作温度，压力低，氧耗低等特点，特别适合于日处理煤300-500t的装置。进行了UGI常压气化法，Texaco加压气化法和CFB气化法三种方法的工艺技术比较。     

灰粘聚循环流化床粉煤气化技术(CAGGTM)的开发与应用

灰粘聚循环流化床粉煤气化技术具有可充分利用6mm以下的粉煤为原料、煤种适应性广、气化炉结构简单、碳转化率90%以上、副产蒸汽、环境友好等特点。介绍了该技术的开发、各项目进展情况以及该技术在工业燃气、石化领域的应用情况。     

串行流化床煤气化试验

针对串行流化床煤气化技术特点,以水蒸气为气化剂,在串行流化床试验装置上进行煤气化特性的试验研究,考察了气化反应器温度、蒸汽煤比对煤气组成、热值、冷煤气效率和碳转化率的影响。结果表明,燃烧反应器内燃烧烟气不会串混至气化反应器,该煤气化技术能够稳定连续地从气化反应器获得不含N₂的高品质合成气。随着气化反应器温度的升高、蒸汽煤比的增加,煤气热值和冷煤气效率均会提高,但对碳转化率影响有所不同。在试验阶段获得的最高煤气热值为6.9 MJ•m^-3,冷煤气效率为68％,碳转化率为92％。     

灰熔聚粉煤气化技术运行中出现的问题及措施

灰熔聚循环流化床粉煤气化技术是我国具有自主知识产权的新型煤气化技术。介绍了该技术的特点、工艺流程,总结了在应用中出现的问题及一些整改措施。     

水蒸气/氧流化床两段煤气化制备低焦油合成气工艺实验

由下行床热解和提升管（或输送床）气化组合形成的流化床两段气化将煤气化反应过程解耦为煤热解和半焦气化两个反应阶段,热解产物完全进入气化反应器,利用其中的高温环境和输送的半焦催化作用分别实现焦油的热裂解与催化裂解,完成低焦油气化。利用该流化床两段气化的10 kg/h级实验室工艺实验装置,以榆林烟煤为原料、水蒸气/氧气作为气化剂,变化过量氧气系数ER、蒸汽炭比S/C、热解及气化温度等参数,研究水蒸气/氧流化床两段煤气化制备低焦油合成气的特性。结果表明,流化床两段气化系统可实现稳定运行（实验3 h以上）,在ER=0.36和S/C=0.15时,热解和气化的代表温度分别稳定在735℃和877℃,合成气的CO、CO₂、H₂、CH₄、C _n H _m 和N₂含量分别为14.33%、10.07%、18.39%、9.89%、1.82%和45.50%,相应的合成气产量达到1.8 m³/kg,低位热值8.99 MJ/m³,焦油含量0.437 g/m³,展示了制备低焦油合成气的技术特征。对于实际的长时间连续运行,更高的气化温度将使流化床两段气化具有更好的低焦油特性。     

水蒸气/氧流化床两段煤气化制备低焦油合成气工艺实验

由下行床热解和提升管（或输送床）气化组合形成的流化床两段气化将煤气化反应过程解耦为煤热解和半焦气化两个反应阶段,热解产物完全进入气化反应器,利用其中的高温环境和输送的半焦催化作用分别实现焦油的热裂解与催化裂解,完成低焦油气化。利用该流化床两段气化的10 kg/h级实验室工艺实验装置,以榆林烟煤为原料、水蒸气/氧气作为气化剂,变化过量氧气系数ER、蒸汽炭比S/C、热解及气化温度等参数,研究水蒸气/氧流化床两段煤气化制备低焦油合成气的特性。结果表明,流化床两段气化系统可实现稳定运行（实验3 h以上）,在ER=0.36和S/C=0.15时,热解和气化的代表温度分别稳定在735℃和877℃,合成气的CO、CO₂、H₂、CH₄、C _n H _m 和N₂含量分别为14.33%、10.07%、18.39%、9.89%、1.82%和45.50%,相应的合成气产量达到1.8 m³/kg,低位热值8.99 MJ/m³,焦油含量0.437 g/m³,展示了制备低焦油合成气的技术特征。对于实际的长时间连续运行,更高的气化温度将使流化床两段气化具有更好的低焦油特性。     

Modelling and simulation of a coal gasification process in pressurized fluidized bed

A coal gasification mathematical model that can predict temperature, converted fraction and particle size distribution for solids have been developed for a high pressure fluidized bed. For gases in both emulsion and bubble phase, it can predict temperature profiles, gas composition, velocities and other fluid-dynamic parameters. In the feed zone, it could be considered a Gaussian distribution or any other distribution for the solid particle size. Experimental data from literature have been used to validate the model. Finally, the model can be used to optimize the gasification process changing several parameters, such as excess of air, particle size distribution, coal type and reactor geometry.     

浅谈煤气化技术进展及选择

阐述了研究和开发煤气化技术的重要意义,详细介绍了目前国内外主流煤气化技术的进展及应用,比较了各种煤气化技术的优缺点,并对如何选择煤气化技术提出了自己的看法。     

鼓泡流化床垃圾衍生燃料富氧气化

在鼓泡流化床上进行两种垃圾衍生燃料(RDF)的富氧气化试验,考察了RDF的热重特性并分析了气化温度、当量比及富氧浓度对气化特性的影响.结果表明:两种RDF均由纤维素及塑料类组分构成.随着温度由650℃升高至800℃,两种RDF产气的H₂、CO及CH₄浓度均逐渐增加,产气热值和气化效率同时提高.当量比增大时可燃组分浓度先略有增大后逐渐减小,但气体产率不断增大.RDF1及RDF2分别在当量比为0.22及0.27处达到最佳气化效率.富氧气化可有效改善气化品质,提升合成气热值,富氧浓度为45%时RDF1及RDF2合成气热值均达到最大,分别为8.6 MJ·m^-3及9.2 MJ·m^-3.     

A mathematical model of fluidized bed biomass gasification

A mathematical model of biomass gasification in a fluidized bed has been developed. It considers axial variations of concentrations and temperature in the bubble and emulsion phases. The mass balance involves instantaneous oxidation and equilibrium devolatilization of the biomass, kinetics of solid-gas gasification reactions as well as of gaseous phase reactions and interphase mass transfer and gas convection. The energy balance is solved locally for each vertical volume element, and globally on the reactor by iteration on the temperature at the bottom of the bed. Three parameters have been adjusted based on the experimental results: the heat transfer coefficient at the wall, the weighting of the kinetics of the water-gas shift reaction and the fraction of biomass carbon remaining as char after devolatilization. The model is used to simulate a pilot scale (50 kg/h) biomass gasifier, and its predictions compared to experimental measurements. The temperature and gaseous concentrations are estimated with good accuracy for the experiments using a wood feedstock, except for the concentration of hydrogen which is overestimated.     

Coal pyrolysis and gasification in a fluidized bed thermogravimetric analyzer

The kinetics and modelling of coal gasification were studied in the newly developed fluidized bed thermogravimetric analyzer. The total weight loss obtained from the fluidized bed reactor and the total gas product are in general agreement. The presented model for the micro‐fluidized bed reactor encompasses the kinetics of coal pyrolysis as well as the gasification reactions. For coal pyrolysis, the resulting activation energies for the individual gases were 34.7 to 59.8 kcal/mol. These values are 19 to 21 % lower than those found in the literature for similar coals. This decrease of the activation energies of the endothermic pyrolysis reactions is attributed to a gradient of temperature of 185 to 209 °C. The obtained activation energy for the CO shift reaction is 46.6 kcal/mol, increasing by 20 % from the one used in the literature. This increase of the activation energy of such a mildly exothermic reaction represents an equivalent of 170 °C gradient of temperature. The effects of temperature on the yield and the composition of the gas product are studied. Experimental results and equilibrium data are also compared. The model shows reasonably good agreement with the experimental results, except for the water gas shift reaction.

     

Fluidized bed gasification of coal

Gasification of high ash India coal has been studied in a laboratory-scale, atmospheric fluidized bed gasifier using steam and air as fluidizing media. A one-dimensional analysis of the gasification process has been presented incorporating a two-phase theory of fluidization, char gasification, volatile release and an overall system energy balance. Results are presented on the variation of product gas composiiton, bed temperature, calorific value and carbon conversion with oxygen and steam feed. Comparison between predicted and experimental data has been presented, and the predictions show similar trends as in the experiments.