Hydrated lime was tested for removing phosphoric pentoxide during the premixed combustion of yellow phosphorus tail gas in fluidized bed. The effect of temperature on the retention of phosphoric pentoxide in hydrated lime was examined by changing air fuel ratio. XRD, SEM and EDS techniques were used to analyze and characterize fresh sorbent and sorbent after reaction. The computer software package FactSage6.2 was used to predict solid product. The results show that the highest temperature of yellow phosphorus tail gas premixed combustion in fluidized bed is 1 060 ℃. Within flow ratio of air to fuel from 1.7 to 4.2, the temperature can be stabilized above 870 ℃. The sorbent can react with phosphoric pentoxide and removal efficiencies increase with the increase of the temperature. Phosphoric pentoxide removal by hydrated lime is 86% at 1 060 ℃, 47% at 920 ℃, and 30% at 870 ℃ in fluidized bed, respectively. The sorbent reacts with phosphoric pentoxide firstly forming basic calcium phosphate, and then changing into calcium phosphate. At high temperature, calcium phosphate changes into calcium pyrophosphate. Solid product predicted results are consistent with the experimental results.%通过流化床预混燃烧黄磷尾气,在燃烧过程中加入氢氧化钙,对黄磷尾气燃烧产生的五氧化二磷进行去除.改变空燃比考察反应温度对去除率的影响,对吸收剂进行XRD,SEM,EDS物相表征和微区元素分析,采用FactSage6.2热力学软件对生成的固体产物进行预测.研究结果表明:流化床预混燃烧黄磷尾气,最高温度1 060℃,在空燃比1.7～4.2的范围内炉内温度能稳定在870℃以上.吸收剂可同五氧化二磷反应,吸收率随温度升高而增加,1 060℃时吸收率为86％,920℃时吸收率为50％,870℃时吸收率为30％;氢氧化钙同五氧化二磷首先形成碱式磷酸钙,之后变为磷酸钙,在高温下磷酸钙转变为焦磷酸钙.固体产物的预测结果与实验结果一致.
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