Solid distribution in pelleting fluidized bed：numerical modeling and lab-scale measurement
In this study,one-dimensional model for the solid distribution of flocculated suspensions in pelleting fluidized bed is investigated considering both upflow velocity and hydrodynamic dispersion effects.The solution of the model equation predicts that the solid concentration will decrease remarkably along with the height of suspended layer.And according to the characters of pellet floes.operating conditions such as upflow flux.flocculent dosage and stirring speed perhaps affect the variation Of SS.The following lab-scale experimental works with synthetic ferric-sludge pelleted with PAM confirm the numerical predictions.SS in various heights of the underdosed.optimal dosed and overdosed pelleting suspensions is analyzed.The results show that higher dosage of PAM will cause more dramatically SS variation due to the larger diameter of the pelleting panicles.The experiment also shows that upflow flux has slight effect on the solid fraction distribution trend of the suspended layer.Moreover,various stirring speeds within fitful range has no significant effect on the suspended layer.But too fast stirring will cause SS increasing at the top of the layer due to the breakage of pellet floes.
Pelleting flocculation solid distribufion upflow flux pelleting suspensions
Gang ZHANG Ting-Lin HUANG Ning GUO Zhan-Peng LI Jian-Xin TANG
School of Environmental and Municipal Engineering,Xian University of Architecture and Technology,Xi School of Environmental and Municipal Engineering,Xian University of Architecture and Technology,Xi
国际会议
西安
英文
233-239
2008-05-15（万方平台首次上网日期，不代表论文的发表时间）