Discussion on Key Problems of Depth Peak Adjustment for Large Coal-Fired Boilers

Abstract

[Introduction] With the establishment of China's "carbon peak and neutrality" goal and the urgent need to build a clean, low-carbon, safe, and efficient modern energy system, the proportion of renewable energy in the power grid will increase year by year. However, due to its randomness and intermittent characteristics, the contribution of renewable energy to power peak shaving is extremely limited. To improve its ability to absorb renewable energy, coal-fired power units with good peak-shaving potential are playing an important role in the basic regulation energy. Among them, the coal-fired boiler is the front-end core system of the coal-fired power unit, and its low (variable) load operation performance directly affects the overall peak-shaving capacity of the coal-fired power unit. [Method] Therefore, starting from the combustion stability, operating reliability, environmental protection, and economic requirements during low (variable) load operation of coal-fired boilers, this paper analyzed and summarized the current main research content and progress from four aspects, including combustion stability under low (variable) load operation, environmental protection and economy, adaptability and safety of main auxiliary equipment, and thermo-electrolytic coupling of the thermal power unit. [Result] On this basis, the research and development prospects of the technologies for deepening the peak shaving capacity of coal-fired boilers are put forward. [Conclusion] Through the analysis, it is concluded that to give full play to the first-mover advantage of coal-fired boilers in improving the power peak-shaving capacity, we should focus on the overall system of coal-fired boilers, comprehensively carry out monitoring and evaluation of the operation status of main auxiliary machinery, research on key influencing factors of combustion performance, conduct process intelligent optimization control and prediction. Thereby improving the overall performance of coal-fired boilers in low-load operation, rapid start-stop, and load-lifting.

Keywords

• flexible peak shaving of power grid
• coal-fired boiler
• combustion stability
• operational reliability
• environmental protection and economy