燃高硫无烟煤超超临界W火焰锅炉受热面高温腐蚀应对措施

Countermeasures for High Temperature Corrosion of Ultra Supercritical W⁃flame Boiler Burning High Sulfur Anthracite

超临界W火焰锅炉已广泛用于燃用无烟煤或低挥发分贫煤,相比国内已批量投运的超超临界燃煤机组,配套燃用无烟煤的W火焰锅炉的发电机组的供电煤耗普遍较高,为进一步提高燃用无烟煤发电机组经济性,降低机组碳排放量,提高机组参数是有效措施之一。但我国部分地区无烟煤含硫量较高,提高机组参数后的锅炉受热面面临高温腐蚀风险。针对燃用高硫无烟煤的超超临界W火焰锅炉面临的水冷壁及高温级受热面高温腐蚀风险,提出针对性的工程应对措施,抑制水冷壁区域还原性气氛、防止火焰刷墙及水冷壁喷涂可有效减缓水冷壁高温腐蚀,合理控制高温级受热面壁温偏差、合理布置吹灰器以避免硫酸盐沉积以及选择合理的金属材料等可有效减缓高温级受热面高温腐蚀。

Supercritical W⁃flame boiler has been widely used for burning anthracite or low volatile lean coal.Compared with the domestic ultra supercritical coal⁃fired units that have been put into operation in batches,the power supply coal consumption of W⁃flame boiler with anthracite is generally higher.In order to further improve the economy and reduce the carbon emission of anthracite fired units improving unit parameters is one of the effective measures.However,some anthracite coal has a high sulfur content in China,and the boiler with higher unit parameters is faced with high temperature corrosion risk.Aiming at the high temperature corrosion risk of water wall and high temperature heating surface of ultra supercritical W⁃flame boiler burning high sulfur anthracite,corresponding engineering countermeasures were proposed.Improving the reducing atmosphere of water wall area,preventing flame brush wall and water wall spraying,can effectively slow down the high temperature corrosion of water wall.Reasonable control of the wall temperature of high temperature heating surface,arrangment of soot blower to avoid sulfate deposition and selecting reasonable metal materials,can effectively slow down the high temperature corrosion of high temperature heating surface.