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传统的用来生产工业和民用中等热值气体的生物质热解过程面临着两个缺点,即产气率低和高含量的气相焦油蒸汽引起的下游设备的腐蚀.为克服这些缺点,在保证热解气热值几乎不变的条件下,在实验室内的一套热解系统中研究了运行和设计参数对生物质热解过程的影响.研究的参数包括反应温度、挥发相在热解炉中的停留时间、生物质原料颗粒的预处理、外部加热炉的加热速率和热解炉的热质传递能力.此外,本文还研究了一个独立的裂解炉的运行温度和热解炉的几何形状对燃料气生产的影响.结果表明,上述参数对生物质热解气的产率是敏感的,而且热解气的热值始终在13~15MJ/m^3之间变化.这一热值确保热解气可以较好地用作燃气轮机的动力燃料或炊事燃料. 相似文献
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生物质固定床热解特性的试验研究与分析 总被引:15,自引:5,他引:10
对稻杆、稻壳、木屑在固定床热解反应器内的热解特性进行研究,考察热解反应温度和生物质种类对热解特性的影响,分析了热解产物的性质。结果表明,三种原料热解气的热值在12000 ̄15000kJ/Nm^3之间,可满足民用煤气的热值要求;产气率一般为0.25 ̄0.45Nm^3/kg,其中稻壳的产气率最低;温度对热解产气率、生物油产率的影响很大,对热解气组份、热值、气流率及半焦产率影响也较显著;生物油的特性数据 相似文献
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生物质鼓泡流化床气化特性的空气当量比影响分析 总被引:4,自引:0,他引:4
在鼓泡流化床生物质气化器内,以空气为气化介质,对木屑进行了常压气化试验研究。选择空气当量比ER为0.13~0.33进行试验,研究了在气化温度为760%、810~12和860℃条件下对气化结果的影响。试验结果表明:主要燃气成分含量H2:6.2%~14.1%,CO29.9%~30.2%,CH4:1.6%~11.2%,产气率:1.0m3/kg~1.740/kg,产气低位热值:3526kJ/m3~9184kJ/m3,碳转换率:52.3%~82.3%,气化效率38%~69.1%。 相似文献
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城市生活垃圾中废弃木料流化床热解气化试验研究 总被引:1,自引:1,他引:0
为开发适合我国城市生活垃圾处理的低污染气化熔融技术,对城市生活垃圾中广泛存在的废弃木料组分进行了流化床热解与气化试验。流化床中,在反应温度400~700℃、过量空气系数0~0.8的范围内,对木料进行了系统的热解气化试验,分析了反应产物特性及其产量变化规律。结果表明,热解温度5000℃,热解油产量最大,可占原料质量的38%,热解气产量随温度增加而增大;气化温度600℃、过量空气系数0.4时,气化效率最高,达到73%,此时每标准立方米气化气热值为5800kJ,气化气产率为2.01m^3/kg;并进行相关的反应特性及机理分析。 相似文献
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以水稻、小麦、玉米、棉花、油菜5种农作物秸秆为研究对象,采用管式炉对其进行热解实验,探讨热解产气量的差异性。实验结果表明在5种生物质秸中,油菜秸热解产气率为0.28 L/g,热解产物中的CO和H2气体含量分别为31.6%和26.3%,原料热值与热解燃气中可燃气体的低位热值分别为12345.84 kJ/kg和10.51 MJ/m3,5项值在5种秸秆中均为最高。5种秸秆样品的SEM照片显示其表质层分布和筛管结构形状、大小均不相同;样品的C元素含量、O/C原子比率及颗粒结构的差异会影响其热解产气总量与产物中CO气体含量。 相似文献
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《可再生能源》2015,(9)
以树枝秸秆及废轮胎整胎为原料,在"反烧"式固定床气化炉中以空气为气化剂进行气化实验研究。结果表明,随着空气当量比ER的增加,炉内气化温度升高,气化效率提升,当ER为0.30时,炉内温度达到750℃,气化效率为56.45%,气体热值为4.68 MJ/m3;随着原料中废轮胎比例的增加,气化效率有所提高,燃气热值升高,当废轮胎质量含量为44%时,气化效率达到60.21%,气体热值为5.34 MJ/m3;气化温度是影响气化效率和气体热值的最重要因素,提高空气当量比可以使炉内温度升高,强化气化效果;同时原料中废轮胎比例也对气化效率及气体热值有较大影响,废轮胎质量含量为40%~50%较为适宜。废轮胎以整胎形式与生物质共气化是废轮胎处置与资源化利用的有效方式。 相似文献
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建立下吸式生物质气化炉热力学平衡模型,该模型包括焦炭、焦油和气体,并用已公布的实验数据对模型进行验证,均方根(RMS)在1.304~3.814之间,结果表明该模型的预测值与实验数据吻合较好,可认为模型可靠。然后模拟棉秆在下吸式生物质气化炉中以空气和富氧气体2种气化氛围下,不同操作参数(当量比、预热温度和气化炉反应温度)下对棉秆气化的气体组分、热值和产率的影响。模拟结果表明:富氧气体为气化剂时,当量比从0.20增至0.35时,气体中N2含量比空气显著下降,达10%以上,同时发现能提高气体中H2和CO的含量和热值,热值比空气提高约20%。预热温度对气化成分变化影响有限,随预热温度从30 ℃变化到130 ℃,气体的平均热值从空气的5.2 MJ/m3提高到富氧气体的7.0 MJ/m3。随气化炉内反应温度从750 ℃升至1250 ℃,空气和富氧气体2种气化剂下的H2和CO分别从20.94%、26.84%和21.77%、28.67%下降到4.06%、9.12%和10.49%、21.60%,导致气体的热值降低。 相似文献
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An atmospheric test system of dual fluidized beds for coal multi-generation was built.One bubbling fluidized bedis for gasification and a circulating fluidized bed for combustion.The two beds are combined with two valves:one valve to send high temperature ash from combustion bed to the gasification bed and another valve to sendchar and ash from gasification bed to combustion bed.Experiments on Shenhua coal multi-generation were madeat temperatures from 1112 K to 1191 K in the dual fluidized beds.The temperatures of the combustor are stableand the char combustion efficiency is about 98%.Increasing air/coal ratio to the fluidized bed leads to theincrease of temperature and gasification efficiency.The maximum gasification efficiency is 36.7% and thecalorific value of fuel gas is 10.7 MJ/Nm3.The tar yield in this work is 1.5%,much lower than that of pyrolysis.Carbon conversion efficiency to fuel gas and flue gas is about 90%. 相似文献
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《International Journal of Hydrogen Energy》2020,45(35):17270-17275
Experimental investigation of gasification of oil shale dust in a counterflow moving bed filtration combustion reactor was carried out. The process was implemented similar to filtration combustion of gases: pulverized solid fuel supplied simultaneously with oxidizer. For a controlled supply of fuel dust a new rotating dispenser was used. Characteristics of process depending on the equivalence ratio were obtained. The absence of a rise in pressure drop over time indicates the lack of fuel accumulation and ash inside the porous bed, all ash was carried out from the reactor with a gas stream. It is shown that an increase in the flow rate of a gaseous oxidizer leads to an increase in both temperature and the inert velocity. The inert velocity, the calorific value of gaseous products, and the efficiency of gasification increase almost linearly with the equivalence ratio. Proposed method allows producing combustible gaseous products without a noticeable concentration of pyrolysis tars and calorific value up to 4 MJ/m3, gasification efficiency was ~85%. 相似文献
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针对超低热值燃气燃烧CO排放高的问题,设计开发了同心套筒多孔介质燃烧系统,分别研究了过量空气系数、水蒸气和氧气对以CO为单一可燃气体的超低热值燃气的燃烧特性及污染物排放的影响。结果表明:在预热阶段,内部点火相比较于外部点火能够减少1/3的预热时间;热值为3.0 MJ/m~3的超低热值气体在增大过量空气系数时,能够有效降低CO排放,而2.5和2.0 MJ/m~3的超低热值燃气没有效果;空气系数为1.00的条件下,通过添加质量分数为2%~4%的水蒸气未能降低CO排放;在超低热值燃气中通入氧气可以有效降低CO排放,空气系数为1.00时,在3.0 MJ/m~3的超低热值燃气中添加质量分数为12%的氧气,CO排放最低能降到体积分数53×10~(-6)。 相似文献
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Kung-Yuh Chiang Yun-Xi LinCheng-Han Lu Kuang-Li ChienMing-Hui Lin Chih-Chao WuShan-Shin Ton Jiann-Long Chen 《International Journal of Hydrogen Energy》2013
This study investigated the feasibility of gasification of rice straw using an Fe/Mn sludge as a catalyst. The Fe/Mn sludge contained iron and manganese compounds produced from a water purification plant. The gasification temperature and equivalent ratio (ER) was set at 900 °C and 0.30, respectively, with an amended catalyst ratio of 0%–15%. Experimental results indicated that the combustible gas production was increased from 0.61 m3/kg to 0.72 m3/kg with the Fe/Mn sludge addition. The lower heating value (LHV) of combustible gas and energy density (ED) were also increased with an increase in Fe/Mn sludge addition. The LHV and ED increased from 14.76 MJ/Nm3 to 15.82 MJ/Nm3 and from 1.37 MJ/MJ to 1.47 MJ/MJ, respectively. In conclusion, the catalytic gasification of rice straw was more efficient on an energy yield basis with the Fe/Mn sludge addition. The Fe/Mn sludge used in this research has been developed as a potential catalyst for the application of rice straw gasification. 相似文献
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《International Journal of Hydrogen Energy》2019,44(5):2603-2619
A comprehensive mathematical model to simulate a serial composite process for biomass and coal co-gasification has been built. The process is divided into combustion stage and gasification stage in the same gasifier, it is a new process for the co-gasification of biomass and coal. The model is based on reaction kinetic, hydrodynamics, mass and energy balances, it is a one-dimensional, K-L three-phase, unsteady state model. The model is divided into two sub-models, one is the combustion sub-model, the other is the coal-biomass serial gasification sub-model. Combustion sub-model includes coal pyrolysis, dense phase combustion, and dilute phase combustion model. Gasification sub-model includes biomass pyrolysis, dense phase coal gasification, dense phase biomass gasification, and dilute phase gasification model. The model studies the effects of key parameters on gasification properties, including gasification temperature, S/B, B/C, and predicts the composition of product gas and gas calorific value along the reactor's axis at different time. The model predictions agree well with experimental results and can be used to study and optimize the operation of the process. 相似文献
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Experimental study on cogasification mechanisms of straw and kitchen waste in the fixed-bed gasifier
Yongfeng Qi Xiaowei Shan Meiting Wang Lingzhi Zhao Panle Ge Jiang Wu 《国际能源研究杂志》2020,44(11):8578-8590
The cogasification experiments were carried out by an electric fixed-bed gasifier to explore the cooperative gasification mechanisms of straw and kitchen waste. The effects of temperature, equivalence ratio as well as mixing ratio of straw and kitchen waste containing rice and trench oil on the gasification behaviors were investigated, combining the characterizations with SEM and FTIR. The results showed that the CH4 release volume fraction of single trench oil could up to 90%, as for the mixtures of straw, rice, and trench oil, the rapid reaction of oil could increase the gasification temperature, promote the bond fractures of CC and C H. Thereby those fractured matters could combine CO and H2 to generate CH4, which consequently improved the gas quality from straw gasification. As the equivalence ratio being 0.1 at 800°C, the actual calorific value of released gaseous from the mixture of straw, rice, and oil was at least 26% higher than the theoretical weighting value. When the mass ratio of straw, oil, and rice was 2:0.5:0.5, that superiority even reached 49.31%. Furthermore, in another fixed-bed gasifier without external heating, the mixture of sun-dried straw and actual kitchen waste containing much water could still achieve continuous gasification, and the experimental phenomena were similar to those above with the electric fixed-bed gasifier. The real calorific value of the mixture of straw and kitchen waste was still higher than the theoretical weighting value. 相似文献
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生物质中热值气化装置设计与运行 总被引:5,自引:2,他引:5
从富氧气化的原理和特点出发,根据空气化的结果,讨论说明中热值气化装置的设计依据和参数计算方法,在试验运行的基础上,分析采用富样气化的中热值气化装置的优缺点,通过分析和试验表明,采用90%的富氧气化具有较理想的效果,其气体热值在10-12MJ/m^3之间,气化效率在70%以上,单位燃气的耗电量约0.075kWh/Nm^3,具有较好的经济性和实用性。 相似文献