Gas-particle flow and rapid load-up characteristics of a novel deep peak regulation burner

Abstract

Existing swirling combustion technology, which relies on faulty coal, is unable to meet deep peak shaving demands without auxiliary methods. This paper developed a deep peak regulation burner (DPRB) to achieve stable combustion at 15%–30% of the boiler’s rated load without auxiliary support. Gas-particle tests, industrial trials, and transient numerical simulations were conducted to evaluate the burner’s performance. At full rated load, the DPRB formed a central recirculation zone (RZ) with a length of 1.5d and a diameter of 0.58d (where d represents the outlet diameter). At 40%, 20%, and 15% rated loads, the RZ became annular, with diameters of 0.30d, 0.40d, and 0.39d, respectively, with a length of 1.0d. At 20% and 15% rated loads, the recirculation peak and the range of particle volume flux were comparable to those at 40% rated load. The prototype burner demonstrated that, without oil support, the gas temperature within 0 to 1.8 m from the primary air outlet remained below 609 °C, insufficient to ignite faulty coal. As the load rate increased from 20% to 30%, the prototype’s central region temperature remained low, with a maximum of 750 °C between 0 and 2.0 m. In contrast, the DPRB’s central region temperature reached 750 °C at around 0.65–0.70 m. At a 3%·min^‒1 load-up rate, when the load increased from 20% to 30%, the prototype burner extinguished after 30 s. However, the DPRB maintained stable combustion throughout the process.

Graphical abstract

Keywords

swirl burner / gas-particle flow (GPF) characteristics / numerical simulation / deep peak regulation / rapid load-up capability

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