分布板进气方向对气化炉内颗粒分布的影响
|
摘要
采用MP-PIC (multi-phase particle in cell)方法模拟了三维多段气化炉(上部快速床,下部鼓泡床)多粒径煤粉的循环流化过程,研究了分布板不同进气方向对气化炉内颗粒分布的影响。结果表明:分布板开孔与水平方向夹角越大,物料进入快速床并形成流化状态越快,但对成形后的流化形态影响较小;分布板进气方向对分布板处的轴向颗粒浓度分布影响较大,对快速床内轴向颗粒浓度分布影响较小;随着分布板进气方向与水平夹角的减小,鼓泡床下部颗粒浓度增大,固相颗粒通量增大;分布板进气方向对旋风分离效率影响较小。因此,工程上可根据需要适当减小分布板进气方向与水平方向的夹角来增加分布板上部颗粒浓度分布。
The cyclic fluidization process of different-sized powder coal in 3D multi-stage gasifier(upper fast fluidized bed with lower bubbling fluidized bed) was simulated with MP-PIC(multi-phase particle in cell) method. The effects of different inlet directions of the distributor on particle distribution in the gasifier was studied. Results show that the larger the angle between the open hole and the horizontal direction of the distribution plate, the faster the material enters the fast bed, and the faster the fluidized state is formed. But it has little effects on the fluidized morphology after forming. Changing the inlet directions of distributor mainly affects the axial particle concentration distribution at the distribution plate, but has little influence on the axial particle concentration distribution in the fast bed. As the angle between the inlet direction of the distributor and the horizontal direction decreases, the particle concentration in the lower part of the bubbling bed increases, and the flux of the solid-phase particles increases. The inlet direction of the distributor has little effect on the cyclone separation efficiency. For engineering applications, it may be considered to reduce the angle between the inlet direction for distributor and the horizontal to increase the particle concentration distribution on the distribution plate. The angle between the inlet direction and the horizontal direction can be decreased so as to increase the distribution of particle concentration in the upper part of the plate.
The cyclic fluidization process of different-sized powder coal in 3D multi-stage gasifier(upper fast fluidized bed with lower bubbling fluidized bed) was simulated with MP-PIC(multi-phase particle in cell) method. The effects of different inlet directions of the distributor on particle distribution in the gasifier was studied. Results show that the larger the angle between the open hole and the horizontal direction of the distribution plate, the faster the material enters the fast bed, and the faster the fluidized state is formed. But it has little effects on the fluidized morphology after forming. Changing the inlet directions of distributor mainly affects the axial particle concentration distribution at the distribution plate, but has little influence on the axial particle concentration distribution in the fast bed. As the angle between the inlet direction of the distributor and the horizontal direction decreases, the particle concentration in the lower part of the bubbling bed increases, and the flux of the solid-phase particles increases. The inlet direction of the distributor has little effect on the cyclone separation efficiency. For engineering applications, it may be considered to reduce the angle between the inlet direction for distributor and the horizontal to increase the particle concentration distribution on the distribution plate. The angle between the inlet direction and the horizontal direction can be decreased so as to increase the distribution of particle concentration in the upper part of the plate.
引文
[1] 房倚天, 王志青, 李俊国, 等. 多段分级转化流化床煤气化技术研究开发进展[J]. 煤炭转化, 2018, 41(3): 1-11.
[2] 陈伟博, 程中虎, 房倚天. 气固流化床分布板区流动特性[J]. 化学反应工程与工艺, 2013, 29(6): 488-494.
[3] 陈伟博, 李俊国, 程中虎, 等. 气固流化床中倾斜分布板上射流深度的研究[J]. 化学反应工程与工艺, 2014, 30(1): 10-14.
[4] 洪若瑜. 射流流化床中锥形分布板对流动的影响[J]. 过程工程学报, 2006, 6(6): 864-871.
[5] 朱沈瑾, 卢志明, 石来民, 等. 锥形分布板结构对流化床流动特性的影响[J]. 轻工机械, 2015, 33(2): 18-22.
[6] 李占勇, 王少铁, 王娟, 等. 狭缝型分布板流化床提高核桃壳颗粒的流化效果[J]. 农业工程学报, 2016, 32(9): 225-232.
[7] 林广周, 王德武, 张继军, 等. 分布板对液固流化床换热器颗粒分布的影响[J]. 化学工程, 2011, 39(9): 93-102.
[8] 董淑芹, 司崇殿曹长青, 等. 分布板开孔率对气固流化床流动特性的影响[J]. 化学反应工程与工艺, 2008, 24(5): 433-439.
[9] 王涛, 孟祥奎, 杨慧, 等. 分布器结构对气固鼓泡流化床内气相分布影响的数值模拟[J]. 青岛科技大学学报, 2013, 34(2): 160-166.
[10] 邓小秋, 习常清 , 赵建涛, 等. 基于 A B A Q U S 对流化床分布板的热‐力耦合分析[J]. 太原理工大学学报, 2015, 46(5): 623-628.
[11] 张少峰, 孙姣. 气液固循环流化床颗粒分布板实验研究[J]. 化学工程, 2006, 34(3): 20-23.
[12] LI F, SONG F F, SOFIANE B, et al. MP-PIC simulation of CFB riser with EMMS-based drag model[J]. Chemical Engineering Science, 2012, 82: 104-113.
[13] FENG M Y, LI F, WANG W, et al. Parametric study for MP-PIC simulation of bubbling fluidized beds with Geldart A particles[J]. Powder Technology, 2018, 328: 215-226.
[14] GIDASPOW D. Hydrodynamics of fiuidizatlon and heat transfer: supercomputer modeling[J]. Applied Mechanics Reviews, 1986, 39(1): 1-23.
[2] 陈伟博, 程中虎, 房倚天. 气固流化床分布板区流动特性[J]. 化学反应工程与工艺, 2013, 29(6): 488-494.
[3] 陈伟博, 李俊国, 程中虎, 等. 气固流化床中倾斜分布板上射流深度的研究[J]. 化学反应工程与工艺, 2014, 30(1): 10-14.
[4] 洪若瑜. 射流流化床中锥形分布板对流动的影响[J]. 过程工程学报, 2006, 6(6): 864-871.
[5] 朱沈瑾, 卢志明, 石来民, 等. 锥形分布板结构对流化床流动特性的影响[J]. 轻工机械, 2015, 33(2): 18-22.
[6] 李占勇, 王少铁, 王娟, 等. 狭缝型分布板流化床提高核桃壳颗粒的流化效果[J]. 农业工程学报, 2016, 32(9): 225-232.
[7] 林广周, 王德武, 张继军, 等. 分布板对液固流化床换热器颗粒分布的影响[J]. 化学工程, 2011, 39(9): 93-102.
[8] 董淑芹, 司崇殿曹长青, 等. 分布板开孔率对气固流化床流动特性的影响[J]. 化学反应工程与工艺, 2008, 24(5): 433-439.
[9] 王涛, 孟祥奎, 杨慧, 等. 分布器结构对气固鼓泡流化床内气相分布影响的数值模拟[J]. 青岛科技大学学报, 2013, 34(2): 160-166.
[10] 邓小秋, 习常清 , 赵建涛, 等. 基于 A B A Q U S 对流化床分布板的热‐力耦合分析[J]. 太原理工大学学报, 2015, 46(5): 623-628.
[11] 张少峰, 孙姣. 气液固循环流化床颗粒分布板实验研究[J]. 化学工程, 2006, 34(3): 20-23.
[12] LI F, SONG F F, SOFIANE B, et al. MP-PIC simulation of CFB riser with EMMS-based drag model[J]. Chemical Engineering Science, 2012, 82: 104-113.
[13] FENG M Y, LI F, WANG W, et al. Parametric study for MP-PIC simulation of bubbling fluidized beds with Geldart A particles[J]. Powder Technology, 2018, 328: 215-226.
[14] GIDASPOW D. Hydrodynamics of fiuidizatlon and heat transfer: supercomputer modeling[J]. Applied Mechanics Reviews, 1986, 39(1): 1-23.