燃煤循环流化床锅炉急冷脱硫底渣作为水泥混合材的性能  

Properties of cement material mixed with the rapid water-cooling desulfurized bottom ash of coal-fired CFB boiler

作　　者：王长安[1] 唐冠韬 李昊[1] 车得福[1] WANG Changan;TANG Guantao;LI Hao;CHE Defu(State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China)

机构地区：[1]西安交通大学动力工程多相流国家重点实验室

出　　处：《化工进展》2019年第9期4295-4301,共7页Chemical Industry and Engineering Progress

基　　金：中国博士后科学基金(2018M641885);国家自然科学基金(51506163)

摘　　要：针对循环流化床锅炉(CFB)底渣利用率偏低的问题,提出一种新的底渣处理应用方案--对底渣进行急冷处理后,将其作为脱硫剂或水泥混合材进行综合利用。本文通过搭建CFB锅炉底渣急冷实验系统,制备了不同渣温下的急冷底渣样品;然后选取亿利底渣和42.5标号的水泥作为研究对象,探讨了急冷底渣作混合材对水泥性能的影响。实验结果表明:急冷会破坏底渣颗粒形状,导致外壳成分发生变化。急冷处理不仅造成CaSO4峰值显著降低,而且使得Ca(OH)2的特征峰变强。在相同的CFB底渣掺比下,与原始底渣相比,急冷底渣作为水泥混合材时,虽然无助于提高抗折抗压强度,但能缩短凝结时间,减少安定性值。同时,还能减少水泥标准稠度需水量,提升水泥的密实程度,对水泥的力学性能和抗侵蚀性有着一定的积极作用。A new application strategy to treat the bottom ash of circulating fluidized bed boiler (CFB) was proposed to solve the problem of low utilization of bottom ash. After the bottom ash being rapidly water-cooled, it can be used as desulfurizer or the cement mixture. The experimental system for rapid water-cooling bottom ash was designed to prepare the samples of bottom ash at different temperatures. Then, the Yili ash and the cement of 42.5 grade were selected for the study, and the effect of rapid water-cooling bottom slag was investigated as mixed material on cement properties. The experimental results reveal that the way of rapid water-cooling destroys the shape of the ash particles, and cause change in the composition of the outer shell. The rapid water-cooling treatment not only gives rise to a significant decrease of the peak of CaSO4, but also intensifies the characteristic peak of Ca(OH)2. Compared with the original ash, the rapid water-cooling decreases the flexural and compressive strength under the same CFB bottom slag blend ratio, but it can shorten the setting time and reduce the stability value. Meanwhile, the rapid water-cooling can reduce the water requirement of the cement standard consistency and improve the compactness of the cement, it also has a positive effect on the mechanical properties and corrosion resistance of the cement.

关 键 词：循环流化床 底渣 急冷 水泥 混合材 凝结时间 

分 类 号：TQ172.44[化学工程—水泥工业]