赤泥水合粉煤灰脱硫性能

Desulfurization performance of red mud combined with fly ash

利用RM(赤泥)水合FA(粉煤灰)制备FARM(粉煤灰-赤泥吸附剂),并用于烟气中SO_(2)的脱除,研究了脱除温度、O_(2)体积分数和NO对FARM脱除SO_(2)性能的影响,并揭示了FARM脱硫的作用机理。结果表明:RM水合FA可提升其脱硫能力;脱硫过程主要是化学反应与化学吸附共同作用的结果,FARM中的(CaO)_(12)·(Al_(2)O_(3))_(7)和2MgO·SiO_(2)是脱除SO_(2)的活性物质,脱硫产物以SO_(4)^(2-)的形式存在;合适的脱除温度和O_(2)体积分数有利于脱硫性能的提升,NO的存在可在一定时限内改善脱硫效果,在500℃、5%O_(2)、500 mg/m^(3)SO_(2)和N 2(平衡气)条件下FARM脱硫效率大于90%的穿透时间和硫容分别可达66 min和106.92 mg/g。

The FARM(fly ash-red mud sorbent)was prepared by hydrating FA(fly ash)and RM(red mud),and it was used to remove SO_(2)in flue gas.The effects of removal temperature,O_(2)volume fraction and NO on the SO_(2)removal performance of FARM were studied.The results show that the hydration of FA and RM can effectively enhance its desulfurization capacity.The desulfurization is the result of chemical reaction and chemical adsorption.In the FARM,(CaO)_(12)·(Al_(2)O_(3))_(7)and 2MgO·SiO_(2)are active substances for SO_(2)removal,and the desulfurization products exist in the form of SO_(4)^(2-).Suitable removal temperature and O_(2)volume fraction are conducive to the improvement of desulfurization performance.The presence of NO can improve the desulfurization effect within a certain time limit.Under the conditions of 500℃,5%O_(2),500 mg/m^(3)SO_(2)and N 2(balance),the breakthrough time and sulfur capacity of FARM with desulfurization efficiency greater than 90%are 66 min and 106.92 mg/g,respectively.