滚筒冷渣机能效计算

Energy efficiency calculation of drum slag cooler

为进一步提高滚筒冷渣机的底渣余热利用水平,增加循环流化床锅炉机组收益,建立了滚筒冷渣机本体及机组系统的能效计算模型,并以某350 MW等级的超临界循环流化床锅炉机组为研究目标,计算了其滚筒冷渣机的能效指标。结果表明,对于现役冷渣机,在控制冷却水流量,提高出水温度后,其本体热效率将降低,但系统发电量增加。在出水温度增至150℃时,尽管冷渣机自身效率降至不足90%,但由于冷渣机出水可直接进入除氧器,机组发电量增加值可以超过1. 1 MW。对于新建机组,可在减少冷渣机冷却水流量的情况下维持其热效率不变,当出水温度同样为150℃时,机组的发电功率增加值接近1. 2 MW。因此,不断提高出水温度是冷渣机最重要的技术发展方向。

In order to further improve the utilization of the bottom slag residual heat of the drum slag cooler and increase the revenue of the circulating fluidized bed boiler unit,the energy efficiency calculation model of the drum slag cooler and the unit system were established and calculated based on a 350 MW supercritical CFB boiler unit.The calculation results show that for the present drum slag cooler,the bulk thermal efficiency will decrease after controlling the cooling water flow and increasing the outlet water temperature,while the unit power generation increases.When the outlet water temperature increases to 150 ℃,although the efficiency of the drum slag cooler reduces to less than 90%,the power generation capacity of the unit can increase exceed 1.1 MW since drum slag cooler can directly enter the deaerator.For the new unit,the thermal efficiency can be maintained while reducing the cooling water flow of the drum slag cooler.Further,the power generation value of the unit increases close to 1.2 MW when the outlet water temperature is also 150 ℃.Therefore,continuously increasing the outlet temperature is the most important technical development direction of the drum slag cooler.