准东煤灰渣烧结熔融过程中钠基化合物作用机理研究

将Na₂CO₃添加剂按折算为Na₂O以20%的比例掺入煤灰中制成混合灰样,对混合灰样在不同温度下烧结.对不同温度下的烧结灰进行EDS元素分析和XRD物相分析,探究钠基化合物在准东煤灰烧结过程中的转变机理.并以EDS分析结果为基础用Fact sage 5.2计算软件中的Equilib模块进行化学热力学平衡反应计算.结果表明,随着烧结温度的升高,硫会发生富集,而钠主要和硫反应生成Na₂SO₄.同时会有NaCl的产生,NaCl会与含钾化合物反应置换出KCl.NaCl、KCl和Na₂SO₄与其他物质产生低温共熔物.

Action mechanism of sodium compounds in Zhundong coal ash on the process of sintering and fusion

Na₂CO₃ was added into coal ash with the amount of 20% which was converted into the weight of Na₂O. Then the mixed coal ash samples were sintered under different temperatures. To explore the transition mechanism of sodium compounds in the sintering process, the EDS elemental analysis method and XRD phase analysis method were used to analyze the sintered ash samples. Then chemical thermodynamic equilibrium calculations were carried out on the basis of EDS analysis results with the Equilib module of the Fact sage 5.2 software. And the results were compared with those of the experiment. Results show that sulfur enrichment will occur as the elevating of temperature. Sodium mainly reacts with sulfur to compose Na₂SO₄. At the same time NaCl occurs, and it will react with the potassium compounds to generate KCl. NaCl, KCl and Na₂SO₄ react with other substances to produce low temperature eutectics.