三相流化床中磷石膏分解渣碳酸化反应研究

通过对磷石膏分解渣在三相流化床中碳酸化反应的实验研究,探讨了不同因素对磷石膏分解渣中CaS转化的影响。实验结果表明:增大CO2气体流量和增加反应时间有利于CaS的转化,随着液固比的增大,CaS的转化率首先是增大然后趋于平缓,而升高反应温度对CaS的转化有微弱抑制作用。得到磷石膏分解渣碳酸化反应的最佳反应条件:CO2气体流量为300 mL/min、反应时间为40 min、液固比(体积质量比)为6 mL/g、反应温度为(25±2)℃。在最佳反应条件下,三相流化床中CaS的转化率为97.34%,釜式反应器中CaS的转化率为86.32%,相差了11%。与釜式反应器相比,三相流化床反应器更有利于磷石膏分解渣的碳酸化反应。

Carbonation reaction of phosphogypsum decomposition slag in three-phase fluidized bed

The carbonation reaction of phosphogypsum decomposition slag in the three-phase fluidized bed was studied,and the influence of different factors on the transformation of CaS in the phosphogypsum decomposition slag was discussed.The results show that the increase of CO2 gas flow and the increase of reaction time are good for the transformation of CaS.The conversion rate of CaS increases firstly and then tends to flatten with the increase of the liquid-solid ratio.The rise of reaction temperature has a weak inhibitory effect on the transformation of CaS.The optimum process conditions of carbonation reaction are as follows:the CO2 gas flow is 300 mL/min,the reaction time is 40 min,the liquid-solid ratio(volume-mass ratio) is 6 mL/g,and the reaction temperature is(25±2) ℃.Under the optimum process conditions,the conversion rate of CaS in the three-phase fluidized bed reactor is 97.34% and that in the tank reactor is 86.32%,with an 11% difference.Compared with the tank reactor,the three-phase fluidized bed reactor is more advantageous for the carbonation reaction of phosphogypsum decomposition slag.