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。     

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…     

关于灰熔聚流化床粉煤气化技术的调查

通过对中国科学院山西煤炭化学研究所“灰熔聚流化床粉煤气化技术”的调查，介绍了该技术的关键和先进性、与国内外同类技术的比较以及“灰熔聚”技术面临的挑战和市场机遇。指出“灰熔聚”的工业化将是我国煤气化技术传统产业升级和改造的一次重大革新和突破，对煤气化技术的国产化、提高煤炭利用率、改善环境有十分重要的意义。     

加压灰熔聚流化床粉煤气化技术的研究与开发

在Φ0．2m、压力1．5MPa、日处理量3t-4t煤的加压灰熔聚流化床粉煤气化试验装置上进行了府谷煤的气化试验。考察了压力、温度对煤处理量、碳转化率、排灰碳含量、煤气组成等工艺指标的影响，证实气化强度正比于操作压力的0．7－0．75次方，同时进行了高温颗粒移动床除尘试验。试验运行验证了工艺的可行性。     

加压灰熔聚流化床粉煤气化技术的研究与开发

建立了一套直径０．２ｍ,压力１．５ＭＰａ,日处理量３ｔ￣４ｔ煤的加压灰熔聚流化床粉煤气化试验装置,在该装置上进行了府谷煤的气化试验,考察了压力,温度对煤处理量、碳转化率、排灰碳含量,煤气组成等工艺指标的影响,确定了加压下开工,运行,停车程序。试验运行验证了工艺的可行性,安全可靠性和设备设计的合理性。     

灰熔聚流化床粉煤气化技术

灰熔聚流化床粉煤气化技术是８０年代以来开发研究的。该技术是在流化床用氧化剂形成局部高温的办法来提高碳转化率，因而拓宽了煤种适应性，使灰渣在高温下团聚成又大又重的粒子而减少了排灰碳损失。     

灰熔聚粉煤气化净化工艺改造探讨

0前言 我厂于2004年着手气化改造工程，选用灰熔聚流化床粉煤气化工艺代替重油气化工艺，以解决国内重油资源匮乏、生产难以为继、合成氨成本居高不下的窘境，提高企业的经济效益。灰熔聚流化床粉煤气化装置于2005年6月中旬试投料，目前2台灰熔聚粉煤气化炉已进人调试阶段，正在进一步优化工艺指标和设备磨合。     

灰熔聚流化床粉煤气化技术0.6 MPa工业炉运行概况

介绍了中科院山西煤炭化学研究所开发的灰熔聚流化床粉煤气化技术及其适用范围、工业应用情况。灰熔聚流化床粉煤气化技术具有气化温度适中、氧耗量较低、煤种适应性宽、产品气不含焦油、气化炉耐火材料要求低等优点。同时,对0.6 MPa工业装置的运行情况进行了介绍,总结了0.6 MPa工业装置运行结果,并指出当前需要改进和完善之处。     

新型流化床粉煤多元气化制合成气技术及应用

介绍了灰粘聚循环流化床粉煤气化的原理、工艺流程及工艺特点。该流化床底部设置了灰粘聚分离装置,在炉内形成中心高温区,使炉渣在中心高温区内粘聚成灰球,借助密度差异,有选择地使煤粉与灰球分离,从而降低灰渣的含碳量,提高了煤中碳的转化率。将该技术应用于合成氨生产中,每吨氨可增加综合经济效益295 14元。     

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％。     

U-GAS粉煤流化床煤气化废水设计及运行实例

针对某化工厂排放的U-GAS粉煤流化床煤气化废水成分复杂、有机物浓度高的特点,采用了预处理-IMC生化处理-臭氧氧化-曝气生物滤池组合工艺。给出了主要构筑物及设计参数,阐述了工程设计技术特点。该工程运行结果表明,在进水CODCr、BOD5、NH3-N的质量浓度分别为500、280、180 mg/L的条件下,出水水质可稳定达到GB 8978—1996《污水综合排放标准》一级标准的要求。     

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。     

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.     

Agglomeration of coal ash in fluidized beds

The defluidization behaviour of ash derived from Indian coal by combustion in a fluidized bed has been studied. Sintering temperatures for ash in several ranges of particle size were measured with a dilatometer. In agreement with the earlier work on other coals it was found that above the sintering temperature pairs of complementary, limiting values of fluidization velocity and bed temperatures exist which mark the onset of defluidization when the ash particles are heated in a fluidized bed. A linear relation was observed between bad temperature and limiting defluidization velocity. The constants in the corresponding equations were calculated for two size ranges of particles.     

Influence of ash agglomerating fluidized bed reactor scale‐up on coal gasification characteristics

To study the influence of fluidized‐bed reactor scale‐up on coal gasification characteristics, a model of the ash agglomerating fluidized‐bed reactor has been developed using an equivalent reactor network method. With the reactor network model, the scale‐up effects of a gasifier were studied in terms of the characteristics of the chemical reactions in the jet zone, the annulus dense‐phase zone and the freeboard zone. Results showed that the changes occurred in the inequality proportion of the volume of the jet zone during the reactor scale‐up. Taking into consideration the utilization of a portion of the backflow gas, the expansion of the jet zone volume and the coal particle residence time, the temperature of the jet zone was increased from 1592 to 1662 K. Also, both the annulus dense‐phase zone temperature and the freeboard zone temperature decreased, causing subsequent decrease in the carbon conversion efficiency. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1821–1829, 2014     

Ash-agglomerating gasification of coal in a spouted bed reactor

Australian bituminous coal (Hoskisson) was gasified with oxygen and steam in a 0.4m diameter spouted bed reactor at atmospheric pressure and temperatures of 1050–1170 °C to produce medium calorific value gas. High-ash agglomerates fell through the throat of the spouted bed under restricted gasification conditions, with no simultaneous loss of coal. The effects of temperature, steam-oxygen ratio, coal feed rate and coal size on carbon conversion, production of ash agglomerates, gas composition and decompsition of steam were established.     

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.