燃煤发电机组耦合余热利用技术研究进展

  目的  为实现燃煤发电机组进一步扩大其热电比的需求，结合原有机组特点耦合余热利用技术成为了有效方式之一。现有余热利用技术的适应特点以及调节能力具有较大差异。  方法  综合评述了几种余热回收利用方式，同时对比了其原理、优缺点，并通过介绍常用的评价指标进一步评述了当下余热回收技术的关注点。  结果  对于余热回收利用技术方式，目前主要有烟气余热回收，循环水余热回收，空气源余热回收，工业废气回收等方式。其温度区间分别为120～150 ℃、15～35 ℃、0～60 ℃、300 ℃以下。耦合余热利用技术的评价方法主要包括通过性能评价、经济性评价以及系统参数关联评价，其中以热耗、热效率等评价参数为主。  结论  文章给出了余热回收利用技术的发展方向及相关建议。耦合余热回收利用技术目前主要应用于热泵系统，在未来更高热电比需求下，采用冷端余热供热的低压缸改造技术将成为一大发展重点。

Research Progress of Coupled Waste Heat Utilization Technology for Coal-Fired Power Generating Units

  Introduction  To realize the demand of further expanding the thermal power ratio of coal-fired power generating units, coupled waste heat utilization technology combined with the characteristics of the original units has become one of the effective ways. There are great differences in the adaptive characteristics and regulation capacity of the existing waste heat utilization technology.   Method  Several waste heat recovery and utilization methods were comprehensively reviewed and their principles, advantages and disadvantages were compared. Then the current focus of waste heat recovery technology was further reviewed by introducing common evaluation indicators.   Result  For waste heat recovery and utilization technology, there are mainly flue gas waste heat recovery, recycling water waste heat recovery, air source waste heat recovery, industrial waste gas recovery, and so on. The temperature ranges are 120～150 ℃, 15～35 ℃, 0～60 ℃, and below 300 ℃, respectively. The evaluation methods of coupled waste heat utilization technology mainly include performance evaluation, economic evaluation, and system parameter correlation evaluation, among which the evaluation parameters such as heat consumption and thermal efficiency are the main ones.   Conclusion  The development direction and relevant suggestions of waste heat recovery and utilization technology are pointed out. At present, coupled waste heat recovery and utilization technology is mainly used in the heat pump system. Under the demand for a higher thermal power ratio in the future, the low-pressure cylinder transformation technology using cold end waste heat heating will become a major development focus.