600 MW机组锅炉掺烧劣质煤技术经济性研究

为了减少炉膛结渣，优化劣质煤掺烧和提高电厂收益，通过劣质煤掺烧比例、磨煤机组合方式、炉膛火焰温度、还原气体分布、SO₂质量浓度、结渣行为等现场试验，研究了600 MW亚临界机组锅炉掺烧劣质煤技术经济性。结果表明：机组可采用3台磨煤机掺烧中高硫分煤的方式安全运行，最大掺烧比例为37%，锅炉未出现明显的结渣现象；在最大掺烧比例时，烟气SO₂质量浓度明显上升，但脱硫系统仍有较大裕度；经济性评价表明尽管掺烧小幅增加了供电煤耗，但劣质煤价格低廉使发电成本明显降低。现场试验和经济性评价方面的研究，为同类型机组优化掺烧劣质煤提供了思路和参考。

Technical and Economic Investigation of Blended Combustion with Inferior Coal on 600 MW Unit Boiler

In order to reduce furnace slagging, optimize the blending of inferior coal and increase power plant profit, technical and economic investigation of blended combustion with inferior coal on 600 mw unit boiler was processed through on-site tests, such as the blending ratio of low-grade coal, pulverizer combination, furnace flame temperature, reducing gas distribution, sulfur dioxide concentration, slagging behavior, etc. The results show that the unit can safely operate with three coal mills blended with high-sulfur coal, he maximum mixing ratio is 37%, and there is no obvious slagging in the boiler furnace; at the maximum blending ratio, the sulfur dioxide concentration in flue gas increases significantly, but the desulfurization system still has a large margin; the economic evaluation shows that the low price of low-grade coal reduces the cost of power generation significantly, although the blending slightly increases the net coal consumption rate. The on-site tests and economic evaluations provide ways and references for the optimization of the blending inferior coal for the same type units.