可调卫燃带隔热板的炉内高温环境下工作可靠性的数值模拟

Numerical Simulation on Working Reliability of Adjustable Flame-retardant Furnace With Heat Insulation Board in High Temperature Environment

为了解决燃煤锅炉适应煤种及负荷频繁大幅度变化的深度调峰运行要求,提出一种基于耐火混凝土与内置冷却风管复合结构的实时可调水冷壁隔热板卫燃带技术方案,其技术关键就是隔热板元件在炉内高温条件的耐高温性能及冷却保护。为此,该文设计多种隔热板元件方案,并以600MW机组锅炉为例对可调隔热板在不同位置、不同冷却风量等工况条件下的冷却特性进行数值模拟研究。结果表明:在锅炉满负荷工况下,可调卫燃带隔热板处于全关位置且隔热板纵向转轴两端进口冷却风速大于15m/s时,隔热板耐火浇注料的最高工作温度可以控制在1362K以下,隔热板内置冷却风管的最高工作温度可以控制在835K以下,均低于大多数耐火混凝土与耐热钢的长期工作温度,这说明基于耐火混凝土与内置冷却风管复合结构的实时可调卫燃带隔热板可以在炉内高温环境时长期可靠工作。

In order to meet the requirements of deep loads regulation of coal-fired boilers with frequent and large fluctuations in coal types and loads, a technical scheme of real-time adjustable heat insulation board, which was laid on water-cooled wall of boilers and consisted of refractory and built-in air-cooling tube, was proposed. One of the key technologies was the high temperature resistance and cooling protection of the heat insulation board under high temperature conditions in the furnace. For this reason, the author designed various schemes of heat insulation board components, and took the boiler of 600MW unit as an example to study the cooling characteristics of adjustable heat insulation board under different working conditions such as different positions and different cooling air volume. The results show that the maximum working temperatures of the refractory material and the built-in cooling tube of the insulation board can be controlled below 1362K and 835K respectively when the insulation board is at the fully closed position and the cooling air speed at the both ends of the longitudinal rotating tube-shaft of the insulation board is greater than 15m/s. This fact shows that the maximum working temperatures of the structures of the insulation board are far lower than the allowable long-term working temperatures of most refractory and heat-resistant steel. Therefore, the proposed real-time adjustable heat insulation board based on composite structure of refractory and built-in cooling tube can work reliably for a long time under the high temperature environment in the furnace.