含内构件的循环流化床的动态压力特性
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摘要
针对含内构件的循环流化床,以石英砂为物料,使用动态压力传感器测量了含内构件的流化床中气固两相流的动态压力,分析了床内的瞬时压力特性.结果表明,在进出口总压降中,文丘里压降最大,占主床压降的60%以上.表观气速和固体颗粒循环流率共同影响循环流化床内的压力特性.压力瞬时波动功率谱分析表明,压力波动对应一个主频,表观气速越小、颗粒循环流率越大时,压力波动越大,且循环流化床底部压力波动比上部大.加入内构件能有效引导气流,使流动更均匀.
The circulating fluidized reactor is applied widely in desulfurization and denitriding due to high gas-solid contact efficiency. And in order to enhance the effect of mass transfer in solid-gas phase, an internal was installed in the cold circulating fluidized bed(CFB) platform, and the pressure character under different conditions was studied. To investigate the characteristics of pressure fluctuations in circulating fluidized bed, the dynamic pressure of gas solid two-phase flow in circulating fluidized bed riser were systematically measured with quartz sand in it by the dynamic pressure sensors. The results showed that when a complex internal was installed in the CFB, the line of system pressure distribution matches the theory of the pressure balance and presents a shape of "8". The main bed drop includes the inlet pressure drop, the venturi pressure drop, the riser pressure drop and the outlet pressure drop. The venturi pressure drops occupied the major part with a percentage of exceeding 60%. The superficial gas velocity and the particle circulating flow rate affected the main bed pressure drop simultaneously. The inlet pressure drop increased with the increase of the superficial gas velocity, while hardly being affected by the particle circulating flow rate. The venturi pressure drop changed similarly with the main bed pressure drop. The outlet pressure drop increasesd slightly with the increase of the superficial gas velocity, while hardly being affected by the particle circulating flow rate. The power spectrum analysis of the transient pressure of the circulating fluidized bed showed that the pressure fluctuation had a corresponding dominant frequency which had the corresponding size of vibrational energy. The smaller the superficial gas velocity was, the larger the particle circulating flow rate was, and the pressure fluctuation would be bigger. The system pressure drop increased with the increase of the height of the particle in the pipe. And the component could increase the pressure in the circulating fluidized bed and also reduced the non-uniform degree of the pressure while optimizing the flowing field.
The circulating fluidized reactor is applied widely in desulfurization and denitriding due to high gas-solid contact efficiency. And in order to enhance the effect of mass transfer in solid-gas phase, an internal was installed in the cold circulating fluidized bed(CFB) platform, and the pressure character under different conditions was studied. To investigate the characteristics of pressure fluctuations in circulating fluidized bed, the dynamic pressure of gas solid two-phase flow in circulating fluidized bed riser were systematically measured with quartz sand in it by the dynamic pressure sensors. The results showed that when a complex internal was installed in the CFB, the line of system pressure distribution matches the theory of the pressure balance and presents a shape of "8". The main bed drop includes the inlet pressure drop, the venturi pressure drop, the riser pressure drop and the outlet pressure drop. The venturi pressure drops occupied the major part with a percentage of exceeding 60%. The superficial gas velocity and the particle circulating flow rate affected the main bed pressure drop simultaneously. The inlet pressure drop increased with the increase of the superficial gas velocity, while hardly being affected by the particle circulating flow rate. The venturi pressure drop changed similarly with the main bed pressure drop. The outlet pressure drop increasesd slightly with the increase of the superficial gas velocity, while hardly being affected by the particle circulating flow rate. The power spectrum analysis of the transient pressure of the circulating fluidized bed showed that the pressure fluctuation had a corresponding dominant frequency which had the corresponding size of vibrational energy. The smaller the superficial gas velocity was, the larger the particle circulating flow rate was, and the pressure fluctuation would be bigger. The system pressure drop increased with the increase of the height of the particle in the pipe. And the component could increase the pressure in the circulating fluidized bed and also reduced the non-uniform degree of the pressure while optimizing the flowing field.
引文
[1]高金龙.半干法脱硫系统反应器内固体颗粒浓度分布的测量与优化[D].杭州:浙江大学,2013:6-10.Gao J L.Measurement of solid particles distribution in the reactor of semi-drv flue gas desulfurization[D].Hangzhou:Zhejiang University,2013:6-10.
[2]汪军盛,叶猛,朱廷钰,等.循环流化床脱硫反应器流场特性实验研究[J].贵州大学学报(自然科学版),2014,31(2):129-135.Wang J S,Ye M,Zhu T Y,et al.Experimental study on the flow field characteristics in the circulating fluidized bed desulfurization reactor[J].Jourual of Guizhou University(Natural Sciences),2014,31(2):129-135.
[3]Jie X,Li Q H,Tan Z C,et al.Characterization of the flow in a gas-solid bubbling fluidized bed by pressure fluctuation[J].Chem.Eng.Sci,2017,174:93-103.
[4]Zhou Y G,Peng J,Zhu X,et al.Hydrodynamics of gas-solid flow in the circulating fluidized bed reactor for dry flue gas desulfurization[J].Powder Technol.,2011,205(1):208-216.
[5]Wang C P,Lu Z,Li D K.Experimental study of the effect of internals on optimizing gas-solid flow in a circulating fluidized bed[J].Powder Technol.,2008,184(3):267-274.
[6]Zhu H Y,Zhu J.Characterization of fluidization behavior in the bottom region of CFB risers[J].Chem.Eng.J.,2008,141(3):169-179.
[7]李少华,张庆喆,王虎,等.内构件对CFB-FGD塔内固体颗粒径向运动特性影响实验研究[J].锅炉技术,2014,45(2):30-34.Li S H,Zhang Q Z,Wang H,et al.Experimental research on the effect of internals on solid particle radial movement characteristics in the CFB-FGD[J].Boiler Technology,2014,45(2):30-34.
[8]严枭,王子健,卢春喜.环隙下料式流化床-提升管耦合反应器的内截面压力特性[J].过程工程学报,2016,16(6):909-914.Yan X,Wang Z J,Lu C X.Axial distribution of pressure in annular fluidized bed-riser coupled reactor[J].Chin.J.Process Eng.,2016,16(6):909-914.
[9]倪长春,金文成,郑帅,等.基于塔内构件优化的脱硫除尘一体化技术研究[J].机械工业标准化与质量,2017,(9):39-42.Ni C C,Jin W C,Zheng S,et al.Research on integrated desulphurization and dust removal technology based on optimization of internal components[J].Machinery Industry Standardization and Quality,2017,(9):39-42.
[10]高建民,秦裕琨,高继慧,等.循环流化床脱硫塔内流场及气固分离特性数值模拟[J].热能动力工程,2006,21(5):487-490.Gao J M,Qin Y K,Gao J H,et al.Numerical simulation of flow field and gas-particle separation characteristics in CFB-FGD tower[J].Journal of Engineer for Thermal Energy and Power,2006,21(5):487-490.
[11]张锡梅.循环流化床内结构布置对气固流动特性影响的试验研究[D].杭州:浙江大学,2010:75-88.Zhang X M.Experiments on the effect of geometry structure on the gas-solid flow pattern in a circulating fluidized bed riser[D].Hangzhou:Zhejiang University,2010:75-88.
[12]Zhu T Y,He J D,Jing P F.Composite internals for a circulating fluidized bed reactor:US7897116[P].2010-10-27.
[13]汪军盛.循环流化床反应器气固流动特性及脱硫脱硝实验研究[D].贵阳:贵州大学,2014:2-60.Wang J S.Study on the gas-solid flow characteristics and desulfurization-denitriding in the circulating fluidized bed desulfurization reactor[D].Guiyang:Guizhou University,2014:2-60.
[14]张伟.循环流化床锅炉床内流动特性研究[D].保定:华北电力大学,2010:24-34.Zhang W.Investigation on flow character of circulating fluidized bed boiler[D].Baoding:North China Electric Power University,2010:24-34.
[15]周发戚,陈勇,魏志刚,等.循环流化床提升管T形弯头动态压力的小波分析[J].化工学报,2015,66(5):1697-1703.Zhou F Q,Chen Y,Wei Z G,et al.Wavelet analysis of dynamic pressure in T-abrupt of CFB riser[J].J.Chem.Ind.Eng.,2015,66(5):1697-1703.
[16]刘宝勇,魏绪玲,郭庆杰,等.循环流化床提升管压力瞬时波动的功率谱分析[J].应用化工,2012,41(5):752-760.Liu B Y,Wei X L,Guo Q J,et al.Power spectrum analysis of pressure fluctuations in the riser of a circulating fluidized bed[J].Applied Chemical Industry,2012,41(5):752-760.
[17]曹晓阳,周发戚,陈勇,等.循环流化床颗粒输送斜管的压力脉动特性[J].石油学报(石油加工),2016,32(5):913-920.Cao X Y,Zhou F Q,Chen Y,et al.Characteristics of pressure fluctuations in the particle-transport inclined standpipe of a circulating fluidized bed[J].Acta Petrolei Sinica(Petroleum Processing Section),2016,32(5):913-920.
[2]汪军盛,叶猛,朱廷钰,等.循环流化床脱硫反应器流场特性实验研究[J].贵州大学学报(自然科学版),2014,31(2):129-135.Wang J S,Ye M,Zhu T Y,et al.Experimental study on the flow field characteristics in the circulating fluidized bed desulfurization reactor[J].Jourual of Guizhou University(Natural Sciences),2014,31(2):129-135.
[3]Jie X,Li Q H,Tan Z C,et al.Characterization of the flow in a gas-solid bubbling fluidized bed by pressure fluctuation[J].Chem.Eng.Sci,2017,174:93-103.
[4]Zhou Y G,Peng J,Zhu X,et al.Hydrodynamics of gas-solid flow in the circulating fluidized bed reactor for dry flue gas desulfurization[J].Powder Technol.,2011,205(1):208-216.
[5]Wang C P,Lu Z,Li D K.Experimental study of the effect of internals on optimizing gas-solid flow in a circulating fluidized bed[J].Powder Technol.,2008,184(3):267-274.
[6]Zhu H Y,Zhu J.Characterization of fluidization behavior in the bottom region of CFB risers[J].Chem.Eng.J.,2008,141(3):169-179.
[7]李少华,张庆喆,王虎,等.内构件对CFB-FGD塔内固体颗粒径向运动特性影响实验研究[J].锅炉技术,2014,45(2):30-34.Li S H,Zhang Q Z,Wang H,et al.Experimental research on the effect of internals on solid particle radial movement characteristics in the CFB-FGD[J].Boiler Technology,2014,45(2):30-34.
[8]严枭,王子健,卢春喜.环隙下料式流化床-提升管耦合反应器的内截面压力特性[J].过程工程学报,2016,16(6):909-914.Yan X,Wang Z J,Lu C X.Axial distribution of pressure in annular fluidized bed-riser coupled reactor[J].Chin.J.Process Eng.,2016,16(6):909-914.
[9]倪长春,金文成,郑帅,等.基于塔内构件优化的脱硫除尘一体化技术研究[J].机械工业标准化与质量,2017,(9):39-42.Ni C C,Jin W C,Zheng S,et al.Research on integrated desulphurization and dust removal technology based on optimization of internal components[J].Machinery Industry Standardization and Quality,2017,(9):39-42.
[10]高建民,秦裕琨,高继慧,等.循环流化床脱硫塔内流场及气固分离特性数值模拟[J].热能动力工程,2006,21(5):487-490.Gao J M,Qin Y K,Gao J H,et al.Numerical simulation of flow field and gas-particle separation characteristics in CFB-FGD tower[J].Journal of Engineer for Thermal Energy and Power,2006,21(5):487-490.
[11]张锡梅.循环流化床内结构布置对气固流动特性影响的试验研究[D].杭州:浙江大学,2010:75-88.Zhang X M.Experiments on the effect of geometry structure on the gas-solid flow pattern in a circulating fluidized bed riser[D].Hangzhou:Zhejiang University,2010:75-88.
[12]Zhu T Y,He J D,Jing P F.Composite internals for a circulating fluidized bed reactor:US7897116[P].2010-10-27.
[13]汪军盛.循环流化床反应器气固流动特性及脱硫脱硝实验研究[D].贵阳:贵州大学,2014:2-60.Wang J S.Study on the gas-solid flow characteristics and desulfurization-denitriding in the circulating fluidized bed desulfurization reactor[D].Guiyang:Guizhou University,2014:2-60.
[14]张伟.循环流化床锅炉床内流动特性研究[D].保定:华北电力大学,2010:24-34.Zhang W.Investigation on flow character of circulating fluidized bed boiler[D].Baoding:North China Electric Power University,2010:24-34.
[15]周发戚,陈勇,魏志刚,等.循环流化床提升管T形弯头动态压力的小波分析[J].化工学报,2015,66(5):1697-1703.Zhou F Q,Chen Y,Wei Z G,et al.Wavelet analysis of dynamic pressure in T-abrupt of CFB riser[J].J.Chem.Ind.Eng.,2015,66(5):1697-1703.
[16]刘宝勇,魏绪玲,郭庆杰,等.循环流化床提升管压力瞬时波动的功率谱分析[J].应用化工,2012,41(5):752-760.Liu B Y,Wei X L,Guo Q J,et al.Power spectrum analysis of pressure fluctuations in the riser of a circulating fluidized bed[J].Applied Chemical Industry,2012,41(5):752-760.
[17]曹晓阳,周发戚,陈勇,等.循环流化床颗粒输送斜管的压力脉动特性[J].石油学报(石油加工),2016,32(5):913-920.Cao X Y,Zhou F Q,Chen Y,et al.Characteristics of pressure fluctuations in the particle-transport inclined standpipe of a circulating fluidized bed[J].Acta Petrolei Sinica(Petroleum Processing Section),2016,32(5):913-920.