In an era of increasing renewable energy integration, maintaining grid stability has become a critical challenge. Traditional coal-fired power plants, which form a significant part of the energy infrastructure, must adapt to accommodate the fluctuating nature of renewable sources. A recent study published in
Engineering presents a novel solution to enhance the operational flexibility of coal-fired power plants through the use of a pre-gasification burner.
The research, conducted by a team from the Xi’an Jiaotong University and the Key Laboratory for Clean Combustion and Flue Gas Purification of Sichuan Province, explores the potential of pre-gasification combustion technology to improve flame stability and responsiveness under extreme conditions such as ultra-low loads and rapid load changes. The study investigates the performance of a pre-gasification burner on a 5-MW pilot platform through both simulation and experimental verification.
The core concept of the pre-gasification burner involves modifying pulverized coal via gasification to produce high-temperature gasification products before combustion. This process not only enhances flame stability but also reduces the ignition difficulty, a critical factor in achieving flexible operation. The experimental setup included a 75-kW laboratory rig, a 5-MW pilot platform, and a 29-MW industrial boiler. The results indicate that a single pre-gasification burner can maintain flame stability under a 9% load when burning bituminous coal, supporting a fuel load variation rate of 10% per minute.
The study utilized computational fluid dynamics (CFD) and Aspen Dynamics simulations to analyze the dynamic response characteristics of the pre-gasification burner. The simulations revealed that pre-gasification combustion stabilizes more quickly than traditional combustion under disturbances in coal and air flow. Specifically, the pre-gasification burner demonstrated a 40% to 60% reduction in stabilization time compared to traditional combustion methods.
Experimental results from the 5-MW pilot platform confirmed the burner’s ability to achieve stable combustion at ultra-low loads. The pre-gasification chamber maintained a temperature of 750 °C, providing a stable ignition source even at a 9% load. The burner also supported rapid load changes, with a load variation rate of 10% per minute within the 15% to 100% load range.
The research further explored the application of pre-gasification burners in larger industrial boilers. Simulations showed that the burner could support stable combustion at a 15% load in a 29-MW industrial boiler. Additionally, a retrofit design for a 330-MW tangential coal-fired power station boiler demonstrated significant improvements in deep peaking capability, with a 260K increase in temperature at the retrofit layer under a 20% load.
The study concludes that pre-gasification burners offer a promising solution to enhance the flexibility of coal-fired power plants. By improving flame stability and reducing stabilization time under load disturbances, these burners can support stable combustion at ultra-low loads and rapid load changes. This technology has the potential to be applied across various classes of boilers, from industrial to full-scale power station boilers, contributing to the integration of renewable energy sources while maintaining grid stability.
The paper “Improving the Flexibility of Coal-Fired Power Plants via a Pre-Gasification Burner with Ultra-Enhanced Flame Stability,” is authored by Hanlin Zhang, Yixiang Shu, Xuebin Wang, Xu Zhou, Weicheng Li, Haiguo Zheng, Houzhang Tan. Full text of the open access paper:
https://doi.org/10.1016/j.eng.2025.04.015. For more information about
Engineering, visit the website at
https://www.sciencedirect.com/journal/engineering.