Biomass is a kind of renewable energy which is used increasingly in different types of combustion systems or in the production of fuels like bio-oil. Lycopodium is a cellulosic particle, with good combustion propertie...Biomass is a kind of renewable energy which is used increasingly in different types of combustion systems or in the production of fuels like bio-oil. Lycopodium is a cellulosic particle, with good combustion properties, of which microscopic images show that these particles have spherical shapes with identical diameters of 31 μm. The measured density of these particles is 1.0779 g/cm2. Lycopodium particles contain 64.06% carbon, 25.56% oxygen, 8.55% hydrogen and 1.83% nitrogen, and no sulfur. Thermogravimetric analysis in the nitrogen environment indicates that the maximum of particle mass reduction occurs in the temperature range of 250-550 ℃ where the maximum mass reduction in the DTG diagrams also occurs in. In the oxygen environment, an additional peak can also be observed in the temperature range of 500-600 ℃, which points to solid phase combustion and ignition temperature of lycopodium particles. The kinetics of reactions is determined by curve fitting and minimization of error.展开更多
氢基矿相转化技术是处理难选铁矿资源的有效手段,对我国难选铁矿石开发有重要意义。在矿相转化过程的加热阶段,褐铁矿会发生脱羟基行为,物相由褐铁矿转变为赤铁矿,对后续的还原与磨选过程影响较大,但其对应的机理研究较少。针对典型包...氢基矿相转化技术是处理难选铁矿资源的有效手段,对我国难选铁矿石开发有重要意义。在矿相转化过程的加热阶段,褐铁矿会发生脱羟基行为,物相由褐铁矿转变为赤铁矿,对后续的还原与磨选过程影响较大,但其对应的机理研究较少。针对典型包子铺褐铁矿石,考察了加热温度、时间对其氢基矿相转化过程脱水行为的影响,并采用TG-DSC进行热失重分析及非等温动力学计算。试验结果表明:在加热温度700℃,空气流通过5 min的条件下,褐铁矿脱水失重率为5.22%。非等温动力学计算得出:褐铁矿脱水反应的表观活化能为197.62 k J/mol,最概然机理函数为D5扩散模型,积分形式为[(1-α)^(-1/3)-1]^(2),主要限制环节为气体扩散环节。研究明确了包子铺褐铁矿石在氢基矿相转化加热阶段脱水行为的关键参数及机理,为深入理解褐铁矿的氢基矿相转化过程提供了重要依据。展开更多
基金supported by the Ministry of Science, Research & Technology of Iran
文摘Biomass is a kind of renewable energy which is used increasingly in different types of combustion systems or in the production of fuels like bio-oil. Lycopodium is a cellulosic particle, with good combustion properties, of which microscopic images show that these particles have spherical shapes with identical diameters of 31 μm. The measured density of these particles is 1.0779 g/cm2. Lycopodium particles contain 64.06% carbon, 25.56% oxygen, 8.55% hydrogen and 1.83% nitrogen, and no sulfur. Thermogravimetric analysis in the nitrogen environment indicates that the maximum of particle mass reduction occurs in the temperature range of 250-550 ℃ where the maximum mass reduction in the DTG diagrams also occurs in. In the oxygen environment, an additional peak can also be observed in the temperature range of 500-600 ℃, which points to solid phase combustion and ignition temperature of lycopodium particles. The kinetics of reactions is determined by curve fitting and minimization of error.
文摘氢基矿相转化技术是处理难选铁矿资源的有效手段,对我国难选铁矿石开发有重要意义。在矿相转化过程的加热阶段,褐铁矿会发生脱羟基行为,物相由褐铁矿转变为赤铁矿,对后续的还原与磨选过程影响较大,但其对应的机理研究较少。针对典型包子铺褐铁矿石,考察了加热温度、时间对其氢基矿相转化过程脱水行为的影响,并采用TG-DSC进行热失重分析及非等温动力学计算。试验结果表明:在加热温度700℃,空气流通过5 min的条件下,褐铁矿脱水失重率为5.22%。非等温动力学计算得出:褐铁矿脱水反应的表观活化能为197.62 k J/mol,最概然机理函数为D5扩散模型,积分形式为[(1-α)^(-1/3)-1]^(2),主要限制环节为气体扩散环节。研究明确了包子铺褐铁矿石在氢基矿相转化加热阶段脱水行为的关键参数及机理,为深入理解褐铁矿的氢基矿相转化过程提供了重要依据。
