In order to explore Zhundong ash deposition rules, the visualization of fly ash deposition test rig was used to study the deposition characteristics of Zhundong coal under different ashing temperatures. SEM-EDS,XRD and Particles Distribution Instrument were utilized to analyze ash particles. The results showed that the different ashing temperatures led to large differences in characteristics. Existence in the form of calcium is mainly CaCO3 , CaSO4 at 500 ℃ and 650℃ cases, but CaO in the 800℃ case. At 800℃, NaCl is unable to be found in ash and Zhundong coal exists self-desulfurization. In terms of ash deposition characteristic, the 800 ℃ ash is the highest in fouling height because of larger diameter of particles. It is illustrated that the physical factors are the controlling factors at this experimental condition. The "uneven" phenomenon is also appeared at borders for 500 ℃ and 650 ℃ cases, because the particles form voids and are heated to become soft and easy to collapse. It is called "Boundary Roughening", which may be important reasons of fouling and slagging in boilers.%为探究准东煤灰沉积规律和积灰特性,在可视化飞灰沉积试验台上,对不同成灰温度下的五彩湾准东煤灰进行实验研究,并且利用SEM-EDS、XRD、粒度分布仪等对积灰样品进行测试.结果表明:不同成灰温度下的准东煤灰特性差异较大,650℃灰和500℃灰中钙的存在形式主要是CaCO3、CaSO4,而800℃灰主要为CaO;在800℃已经无法检测到NaCl的存在,并且发现五彩湾准东煤存在一定的自脱硫特性;在积灰特性上,颗粒直径较大的800℃灰的积灰高度最高,表明该实验条件下,物理因素为控制因素;650℃灰和500℃灰边界出现"凹凸不平"的现象,推测是在炉内灰颗粒形成孔隙,受热变软塌陷,即"边界粗糙化"现象,而800℃灰边界光滑.
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