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串行流化床生物质气化制氢试验研究 总被引:2,自引:0,他引:2
基于串行流化床生物质气化技术,以水蒸气为气化剂,在串行流化床试验装置上进行生物质气化制氢的试验研究,考察了气化反应器温度、水蒸气/生物质比率(S/B)对气化气成分、烟气成分和氢产率的影响。结果表明:在燃烧反应器内燃烧烟气不会串混至气化反应器,该气化技术能够稳定连续地从气化反应器获得不含N_2的富氢燃气,氢浓度最高可达71.5%;气化反应器温度是影响制氢过程的重要因素,随着温度的升高,气化气中H_2浓度不断降低,CO浓度显著上升,氢产率有所提高;S/B对气化气成分影响较小,随着S/B的增加,氢产率先升高而后降低,S/B的最优值为1.4。最高氢产率(60.3g H_2/kg biomass)是在气化反应器温度为920℃,S/B为1.4的条件下获得的。 相似文献
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生物质气化发电技术讲座(2)生物质气化工艺的设计与选用 总被引:6,自引:0,他引:6
生物质的气化有各种各样的工艺过程。从理论上讲,任何一种气化工艺都可以构成生物质气化发电系统。但从气化发电的质量和经济性出发,生物质气化发电要求达到发电频率稳定、发电负荷连续可调两个基本要求,所以对气化设备而言,它必须保证燃气质量稳定、燃气产量可调,而且必须连续运行。在这些前提下,气化能量转换效率的高低就是影响气化发电系统运行成本的关键。气化形式选定以后,从系统匹配的角度考虑,气化设备应满足以下要求:从实际应用上考虑,固定床气化炉比较适合于小型、间歇性运行的气化发电系统,它的最大优点是原料不用预处理,而且设备… 相似文献
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生物质气化技术研究现状及发展前景 总被引:28,自引:1,他引:28
讨论了生物质气化技术的基本原理和基本过程,阐述了生物质气化反应器(气化炉)及生物质气化的技术关键,指出了气化技术在我国广阔的发展前景。 相似文献
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1 中型生物质气化发电系统。中型生物质气化发电系统一般采用流化床气化工艺,发电规模为400~3000kW。中型生物质气化发电系统在发达国家应用较早,所以技术较成熟,但由于设备造价很高,发电成本居高不下,所以,在发达国家应用极少。近年来,我国开发出了循环流化床气化发电系统,由于该系统有较好的经济性,所以在我国推广很快,已经成为国际上应用最多的中型生物质气化发电系统。 相似文献
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串行流化床生物质气化制取富氢气体模拟研究 总被引:8,自引:1,他引:7
利用串行流化床技术将生物质热解气化和燃烧过程分开,气化反应器和燃烧反应器之间通过灰渣进行热量传递,实现了自供热下生物质气化制氢.利用Aapen Plus软件模拟制氢过程,通过比较单反应器生物质气化的模拟结果和实验结果,验证了模拟研究的可行性.重点研究串行流化床中非催化气化与CaCO3作用下的气化过程,探讨了气化温度、蒸汽与生物质的质量配比(S/B)对制氢的影响,为今后开展生物质气化制氢试验提供了理论参考.结果表明:对应不同气化温度,S/B都存在一个最佳值,且随着温度升高其值减小.当气化温度低于750℃时,添加CaCO3可大幅提高氢产率,气化温度为700℃且在S/B约为0.9时氢产率最大,达43.7 mol·(kg生物质)-1(干燥无灰基),比同温度下非催化气化提高了20.3%.随着气化温度升高,CaCO3促进作用减弱. 相似文献
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生物质流化床气化制取富氢燃气的研究 总被引:17,自引:7,他引:17
以流化床为反应器,对生物质空气-水蒸汽气化制取富氢燃气的特性进行了一系列实验研究。在本实验中,气化介质(空气)从流化床底部进人反应器,水蒸汽从进料点上方通人反应器。在对实验数据进行分析的基础上,探讨了一些主要参数如:反应器温度,水蒸汽/生物质比率S/B(Steam/Biomass Ratio),当量比ER(Equivalence Ratio)以及生物质粒度对气体成分和氢产率的影响。结果表明:较高的反应器温度,适当的ER和S/B(在本实验研究中分别为0.23,2.02),以及较小的生物质颗粒比较有利于氢的产出。最高的氢产率:71gH2/kgbiomass是在反应器温度为900℃,ER为0.22,S/B为2.70的条件下取得的。 相似文献
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本文针对废弃生物的能量再收进行讨论,并用实验测试数据加以论证。在对有代表性的木屑,砻糠、杂草和城市生活垃圾等生物质进行了流化床的冷态模拟和φ200炉子的热态气化试验,得到了满意的结果。主要结论为:固体生物质废料经适当粉碎干燥后即可以用该化床进行资源回收;气化物料度<200mm(单尺度),水份含量<30%时可制得约5μJ/μ~3的粗煤气;采用流化床气化处理法进行资源回收不仅具有废料处理量大(强度达1.5T/μ~2H_r)而且回收的资源能量品位高是最方便实用的气体燃料。 显然,通过本文的研究结果,可以看到目前普通存在的城市垃圾,废弃生物处理的有效手段——流化床处理法的诱人、广泛和美好的前景。 相似文献
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生物质流化床催化气化制取富氢燃气 总被引:11,自引:3,他引:11
以流化床和固定床为反应器,以制取富氢燃气为目标,对生物质催化气化进行了研究。实验所用催化剂为白云石和镍基催化剂。白云石作为流态化催化剂在流化床内使用;镍基催化剂在流化床出口的固定床反应器内使用。重点研究了不同固定床反应条件对气体和氢产率的影响。固定床反应条件为:温度,650~850℃,催化剂质量空速,2.68~10.72h^-1。在催化反应器出口,H2体积平均含量超过50%,CH4含量降低50%左右,C2组分降低到1%以下。在实验条件范围内,最高气体产率可以达到3.31Nm^3/kg biomass,最高氢产率可达到130.28g H2/kg biomass,对镍基催化剂350min的寿命测试表明,该系统具有较稳定的操作性能。 相似文献
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A one-dimensional, steady state, numerical model was developed for a fluidized bed biomass gasifier. The gasifier model consists of a fuel pyrolysis model, an oxidation model, a gasification model and a freeboard model. Given the bed temperature, ambient air flow rate and humidity ratio, fuel moisture content and reactor parameters, the model predicts the fuel feed rate for steady state operation, composition of the producer gas and fuel energy conversion. The gasifier model was validated with experimental results. The effects of major mechanisms (fuel pyrolysis and the chemical and the physical rate processes) were assessed in a sensitivity study of the gasification model. A parametric study was also conducted for the gasifier model. It is concluded that the model can be used for gasifier performance analysis. 相似文献
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In this study, an artificial neural network (ANN) model as a machine learning method has been employed to investigate the exergy value of syngas, where the hydrogen content in syngas reached maximum in bubbling fluidized bed gasifier which is developed in Aspen Plus® and validated from experimental data in literature. Levenberg-Marquardt algorithm has been used to train ANN model, where oxygen, hydrogen and carbon contents of sixteen different biomass, gasification temperature, steam and fuel flow rates were selected as input parameters of the model. Moreover, four different biomass samples, which hadn't been used in training and testing, have been used to create second validation. The hydrogen mole fraction of syngas was also evaluated at the different steam to fuel ratio and gasification temperature and the exergy value of syngas at the point where the hydrogen content in syngas reached maximum were estimated with low relative error value. 相似文献
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Yingfang Li Bo Yang Wei Gao Mohammad Reza Farahani 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(5):544-548
Gasification is extensively used in the biomass utilization industries and can be applied to manage the municipal waste wastes in order to transform solid wastes into a clean syngas. In this work, we developed an artificial neural network (ANN) to simulate the influence of two important hydrodynamic factors, namely, heating rate and gasifier length on hydrogen yield and hydrogen efficiency. Results showed that with the increase of gasifier length, hydrogen yield was increased due to a considerable increase in the rate of reactions with increasing the gasifier length. It was also found that the hydrogen yield reached a constant rate probably due to a significant increase in the heat and mass transfer limitations, especially at the end of gasifier. 相似文献
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This paper presents the thermodynamic assessment of biomass steam gasification via interconnected fluidized beds (IFB) system. The performance examined included the composition, yield and higher heating value (HHV) of dry syngas, and exergy efficiencies of the process. Two exergy efficiencies were calculated for the cases with and without heat recovery, respectively. The effects of steam‐to‐biomass ratio (S/B), gasification temperature, and pressure on the thermodynamic performances were investigated based on a modified modeling of the IFB system. The results showed that at given gasification temperature and pressure, the exergy efficiencies and dry syngas yield reached the maximums when S/B was at the corresponding carbon boundary point (S/BCBP). The HHV of the dry syngas continuously decreased with the increase of S/B. Moreover, the exergy efficiency with heat recovery was averagely a dozen percentage points higher than that without heat recovery. Under atmospheric conditions, lower gasification temperature favored the yield and HHV of dry syngas at various S/B. In addition, it also favored the exergy efficiencies of the process when S/B is approximately larger than 0.75. Under pressurized conditions, higher gasification pressure favored both the yield and HHV of dry syngas, as well as the exergy efficiencies at different S/B. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献