黑液水煤浆主要矿物元素在炉内的迁移和沉积行为研究

为了研究黑液水煤浆的灰沉积机理，采用沿烟气行程从实验炉不同部位抽取空间灰粒和提取相应位置炉壁灰渣样相结合的方法，并与常规水煤浆相对比，研究了各主要矿物元素（Na、K、Si、Al、Fe、Ca）在烟气流中的迁移趋势和沉积特性。并且通过X射线衍射（XRD）和扫描电镜（SEM）等分析从微观角度进行了验证。结果表明，与常规水煤浆不同的是，Na、Si、Al的迁移和沉积是引起黑液水煤浆沾污结渣的主要矿物元素，灰沉积物中主要包括无水芒硝、霞石等低熔融温度富Na物相，而Fe的沉积是次要因素。

Migration and deposition behaviors of main mineral elements in combustion of coal black liquor slurry

To investigate the coal black liquor slurry′s ash deposition mechanism, a new method was proposed by contrast with coal water slurry. Ash particles were extracted from different locations of pilot boiler along the flue gas, in combination with sampling ash residue deposited on fire walls of the same distance from burner. The migrating tendency and deposition characteristics of main mineral elements along the flue gas were investigated in detail. In addition, XRD and SEM were carried out for coal water slurry and coal black liquor slurry′s ash deposit to get validation from microscopic view. The results indicate that the principal mineral elements causing ash deposition of coal black liquor slurry are sodium, silicon and aluminum. The ash deposit is composed of some phases at low fusing temperature, such as thenardite and nepheline. The minor factor is the migration and deposition of Fe, which is different from coal water slurry and coal.