Abstract: With the low-cost advantage of relatively abundant coal resources and the characteristics of ensuring the stable operation of the power system, thermal power units have long occupied a dominant position in our country's energy structure. However, with the increasing global attention to climate change and the proposal of China's carbon peaking and carbon neutrality goals, the environmental pressure caused by the "three wastes" generated during the operation of thermal power units has become increasingly prominent. As a result, thermal power units are facing unprecedented pressure on energy conservation and emission reduction. In this context, the energy-saving transformation and optimization and upgrading of thermal power units have become a research hotspot. At present, the research on energy-saving technology of thermal power units in academia and industry mostly focuses on a single technical field or specific application scenarios, and lacks a systematic combing of the latest progress of mainstream technologies, as well as a comprehensive analysis of the application bottlenecks and research gaps of various technologies, which restricts the coordinated development and large-scale application of energy-saving technologies to a certain extent. In view of this, this work takes the energy-saving technology of thermal power units as the research object, and comprehensively sorts out the current mainstream energy-saving technologies. It includes boiler efficient combustion optimization, heating surface cleaning and transformation, turbine flow part upgrade, waste heat recovery and cascade utilization technology, cold end system optimization and other technologies. In order to evaluate the actual value of various technologies more objectively, this work takes the coal consumption rate as the core economic benefit index, combined with the transformation cases and operation data of typical thermal power units at home and abroad, and deeply analyzes the latest research progress, practical application effects, technical advantages and limitations of different energy-saving technologies. The results show that the energy-saving technology of thermal power units has achieved remarkable results in improving energy efficiency and reducing environmental pollution. However, further research and optimization are still needed in the improvement of multi-objective optimization models, intelligent diagnosis and predictive maintenance, and the application of advanced materials to promote the sustainable development of energy-saving technologies for thermal power units.

Key words: thermal power units, combustion optimization, through-flow transformation, waste heat utilization, heat pumps, cold end system

摘要： 火力发电由于成本低廉、供电平稳等优势，在我国能源结构中长期占据主导地位，但在全球能源低碳转型背景下，伴随火电产生的“三废”使其面临日益严峻的节能减排压力。对火电机组进行节能改造或优化在近年来广受关注，然而目前缺乏对相关技术最新进展和研究空白的全面解析。为此，本工作系统综述了几种主流的火电机组节能技术，包括锅炉和汽轮机的提效改造、余热回收与梯级利用以及冷端系统优化，从煤耗率为主的经济效益指标角度出发，结合典型案例分析了不同节能技术的最新进展及优缺点。火电机组的节能技术在提升能源利用效率和降低环境污染方面取得了显著成效。在多目标优化模型的完善、智能化诊断与预测性维护、先进材料的应用方面仍需进一步研究和优化，以推动热电机组节能技术的持续发展。

关键词: 火电机组, 燃烧优化, 通流改造, 余热利用, 热泵, 冷端系统