松木屑和褐煤流化床的共气化特性

在流化床上以空气-水蒸气为气化介质,对松木屑和褐煤的共气化特性进行了试验研究。在828～928 ℃范围内考察了生物质掺混比例、空气当量比（ER）和水蒸气-燃料比（S/F）对气化气成分、热值、碳转化率及气化效率的影响。结果表明,在生物质掺混比例为50%时,①随着ER值从0.2增加至0.35,CO2含量增加,CO、H2、CH4和CnHm含量减少,气化气热值、碳转换率、气化效率先增加后减少,在ER=0.26时达到最大;②在ER=0.26,S/F从0增加至0.44时,CO2含量增加,CO和H2含量先增加后减少,CH4和CnHm含量减少,气化气热值、碳转化率和气化效率先增加后减少。试验结果表明,在松木屑掺混比例为50%和褐煤共气化过程中,气化气热值最高可达7819 kJ/m3。     

Optimizing the operating conditions for hydrogen-rich syngas production in a plasma co-gasification process of municipal solid waste and coal using Aspen Plus

The plasma gasification process is one of the newest and most innovative approaches to meet the needs of waste management but requires assessment and research on operational conditions prior to installation. In this work, a model based on Gibbs free energy minimization was developed and implemented in Aspen Plus®. A combination of municipal solid waste (MSW) and coal has been used as feedstocks. The model's performance was compared with the results of the literature and found to be in good agreement. The effect of various parameters such as temperature, equivalence ratio, MSW/coal blending ratio, and steam-to-feedstock ratio on the composition of syngas and hydrogen production were assessed. Very interesting results were obtained concerning the mixture of the feedstocks that maximize the hydrogen production besides that using steam as a gasifying agent allows higher hydrogen production than using air. When using high amounts of coal in the feedstock mixture, low steam ratios are preferred. When using high amounts of MSW in the feedstock mixture high steam ratios are preferred. The use of pure oxygen as the gasifying agent increases the hydrogen percentage but requires an air separation unit to be included in the process. The results obtained in this study are particularly relevant for countries with coal reserves.     

以CO_2和H_2O为气化剂的煤焦气化模拟

基于整体煤气化联合循环和燃料电池发电技术,利用固体氧化物燃料电池产生的高温、高纯度CO2与H2O作为煤焦气化的气化剂,运用Aspen Plus模拟软件平台基于Gibbs自由能最小化方法对煤焦的H2O-CO2共气化反应进行了模拟计算。考察了O2流量、H2O流量、CO2流量、预热温度、操作压力、反应温度对气化反应合成气组成和煤气低位发热量的影响。结果显示:通过调节O2流量,得出O2的最佳流量为20 kg/h,此时反应温度和合成气低位热值处于最高值;分别增加水蒸气流量和CO2流量都使反应温度降低,且使反应活性降低导致合成气低位热值降低,所以合理控制水蒸气和CO2流量至关重要;降低操作压力会降低合成气的低位热值,但相对于物料流量改变,影响较小;CO2预热对煤气低位发热量的影响要小于O2的预热效果。     

Hydrogen production from co-gasification of coal and biomass in supercritical water by continuous flow thermal-catalytic reaction system

Hydrogen is a clean energy carrier. Converting abundant coal sources and green biomass energy into hydrogen effectively and without any pollution promotes environmental protection. The co-gasification performance of coal and a model compound of biomass, carboxymethylcellulose (CMC) in supercritical water (SCW), were investigated experimentally. The influences of temperature, pressure and concentration on hydrogen production from co-gasification of coal and CMC in SCW under the given conditions (20–25 MPa, 650°C, 15–30 s) are discussed in detail. The experimental results show that H₂, CO₂ and CH₄ are the main gas products, and the molar fraction of hydrogen reaches in excess of 60%. The higher pressure and higher CMC content facilitate hydrogen production; production is decreased remarkably given a longer residence time. Translated from Journal of Xi’an Jiao Tong University, 2005, 39(5): 454–457 [译自: 西安交通大学学报]     

CO2气氛下煤与蓝藻共气化的行为演变特性

煤与蓝藻共气化是兼顾煤炭高效利用与蓝藻资源化利用的重要途径。采用TG-FTIR联用技术,探究不同掺混比混合物在CO₂气氛下的共气化特性,为其应用化学链燃烧技术提供理论基础。实验表明,蓝藻多糖解聚温度低,于100℃便可析出气相产物。在热解阶段中,DTG曲线有两个失重峰,其中峰值大、温度低的由蓝藻热解产生,主要气相产物为羟基和芳香族化合物;温度较高的失重峰对应煤炭的热解,气相产物以CO、CO₂和烃类为主。均相模型适用于热解、炭化阶段,且对蓝藻的拟合度高于煤炭,而缩核模型对气化阶段和高煤炭比例样品的拟合效果好。共气化的协同作用起始于热解阶段,主要作用区间为气化阶段,掺混蓝藻可有效提高煤焦的气化活性。     

褐煤负载有机钠盐水蒸气气化实验与动力学分析

基于模拟双马来酰亚胺工业废液,通过对负载乙酸钠和碳酸钠的褐煤水蒸气气化的实验,分别研究了反应温度、催化剂负载浓度对气化特性的影响。结果表明:碳酸钠和乙酸钠作为催化剂对褐煤水蒸气气化都具有明显的催化效果,但当碳酸钠的负载量超过10%之后会出现抑制现象,而乙酸钠作为催化剂并没有出现抑制现象;在相同温度或负载浓度的条件下,负载乙酸钠的催化效果要优于负载碳酸钠时的催化效果。对实验数据进行动力学分析发现,均相模型和缩核模型都能够有效描述本研究的实验结果。     

在流化床气化炉中生物质与煤共气化的研究（I）以空气-水蒸汽为气化剂生产低热值燃气

在600kW流化床气化炉工业示范装置上以空气-水蒸汽为气化剂,将生物质／煤按不同比例进行了共气化的实验研究。在实验研究的运行条件下,得到了生物质／煤混合比例对气化炉工作温度、燃气热值、气体产率和气化效率等重要技术参数的影响。对玉米芯／煤的比例为81／19时的典型实验结果表明：气化炉工作温度869℃,空气当量比ER=0．21,S／B=0．20时,气体产率1．96m^3／kg,燃气热值6．4MJ／m^3,气化效率71．3％,燃气中焦油含量小于l0mg／m^3,该炉经过连续运行考核,运行平稳,工况稳定。     

煤焦水蒸气与CO_2共气化技术研究进展及应用展望

简述了煤焦水蒸气与CO2共气化技术的优势和应用现状,综述了国内外该技术的最新理论研究进展,分析了其发展的技术瓶颈和亟待解决的原理性问题,并对该技术可能的应用前景及领域进行了展望。     

生物质与煤在CO_2气氛下共气化特性的初步研究

利用热重分析仪研究了CO2气氛下的生物质半焦、煤焦及其混合焦的反应性,结果表明,在相同条件下,木屑半焦的气化反应性明显高于褐煤半焦.且参与反应的两种半焦,其反应性均随反应速率而提高,而温度也是影响其气化活性的重要因素.研究还发现,在温度高于1 173 K的条件下,混合物半焦的气化反应性较单一组分半焦的反应性差.     

浅析流化床生物质与煤共气化技术方案

针对生物质能源难以单独气化的问题,探讨了生物质与煤共气化的互补性技术方案;介绍了生物质的物理性质和气化特性;论述了灰融聚流化床粉煤气化技术的特点和工艺流程;提出了在灰融聚流化床粉煤气化的基础上进行生物质与煤共气化技术方案,对存在的问题提出了相关解决措施。