为降低亚临界机组的供电煤耗和碳排放，提出了一种在保持机组亚临界蒸汽压力前提下将锅炉主/再热蒸汽温度从540 ℃提升至600 ℃的锅炉受热面改造方案，并以某330 MW亚临界四角切圆锅炉为研究对象，采用三维CFD数值模拟方法对此锅炉的改造方案进行了验证。结果表明，仅需将炉膛折焰角以下3.6 m高度的炉墙水冷壁替换为墙式过热器，即使不对再热器进行改造，锅炉的主/再热蒸汽温度也可同时提升至600 ℃水平。此改造方案可最小程度地改造锅炉受热面，大幅降低锅炉的改造成本和风险。

In order to reduce the net coal consumption rates and CO2 emissions of the subcritical coalfired boilers,this paper presented a boiler heating surface modification solution by which the final superheat and reheat steam temperatures could both be elevated from 540 ℃ to 600 ℃ while the steam pressures remain at subcritical condition. A threedimensional computational fluid dynamics (CFD) simulation was conducted for a typical 330 MW subcritical tangentiallyfired boiler to verify the feasibility of this modification solution. The results show that with only 3.6 m height below arch nose of furnace water wall replaced with wall superheater,both the superheat and reheat steam temperatures can reach the target of 600 ℃ level,even without any modification made to the reheaters. With this heating surface modification design,the required modification to the boiler's heating surface is minimized by which the cost and technical risk of boiler retrofit are greatly reduced.

TK229.6

国家自然科学基金青年科学基金（51906176）