木醋调质石灰石煅烧特性试验研究

Experiment study on calcination characteristics of limestone modified by wood vinegar

新型有机钙协同脱硫脱硝技术在实际应用中存在经济代价高的问题,采用木醋废液调质处理石灰石,制得廉价醋酸钙,并对调质产物的煅烧特性进行了研究。X射线衍射分析结果表明,调质石灰石的主要成分为水合醋酸钙,其煅烧过程大致可以分为3个阶段;采用Avrami理论求解调质石灰石的煅烧反应级数,计算结果其反应级数在0.048～0.272较大范围内波动,进一步证明了反应的多阶段性与无定常性。

Organic calcium is paid attention because of its capability of control SO2 and NOx produced by coal-fired power plant simultaneously.However,the high economic costs will seriously affect its practical application.This experiment attempted to obtain cheap organic calcium through the method of modifying limestone by wood vinegar,an organic acid waste.The phase composition analysis measured by XRD of limestone modified by wood vinegar shows that the major components there in the sample was hydration calcium acetate.TGA result shows that the calcination process of modified limestone could be roughly divided into three stages.The Avrami theory was used to calculate the reaction orders during calcination process at heating rates of 5,20,40K/min respectively.Results calculated using Avrami theory show that the reaction orders of limestone modified by wood vinegar in the conversion range 0.1～0.9 were from 0.048 to 0.272,which further confirmed the multistage characteristic of the calcination process of limestone modified by wood vinegar.