辽源垃圾焚烧项目二次风预热器参数选择分析

Parameter Selection of Secondary Air Preheater for Liaoyuan Waste Incineration Project

以辽源生活垃圾焚烧项目为例,对二次风预热器采用一段式和两段式进行了比较,得出两段式预热器较一段式预热器具有运行时二次风温度调节灵活、适应性好,避免了因一段式预热器故障导致损失,保证了二次风温及燃烧效率的优点。另外,对两段式预热器中间温度也进行了比较,得出中间温度为185℃较140℃有3个优点:当二次风进口温度达到一定值时完全可以只用I段就可达到出口温度设计值;饱和蒸汽耗量减少132%,从而增加了发电量;汽机抽汽为已经部分做功发电完的蒸汽,再从汽轮机抽出来加热预热器,达到了能效利用最大化。

Taking Liaoyuan Waste Incineration Project as an example, through the comparison of one-stage and two-stage secondary air preheater, the two-stage preheater had the advantages of good adaptability and flexible adjustment of air temperature at runtime to avoid the loss during breakdown caused by the one-stage preheater, and ensured the secondary air temperature and combustion efficiency. In addition, based on comparing the intermediate temperature of two-stage preheater comprehensively, there were three advantages when the intermediate temperature is 185 ~C instead of 140 ~C. The first one is the design outlet temperature can be reached by using the first stage only when the secondary air inlet temperature reach a certain value. The second one is the consumption of saturated steam can be reduced by 132%, thus increasing the power generation. The third one is the turbine extraction steam, partially of which has driven the turbine to generate, is extracted again from turbine to heat the preheater to maximize the utilization of energy.