Kai Xu

The global energy transition necessitates a higher share of renewable energy sources, requiring coal-fired power plants (CFPPs) to provide flexible operation to compensate for renewable volatility. Conventional CFPPs are constrained by fuel supply inertia, hindering their ability to meet dynamic grid demands. This paper proposes a novel solution by coupling a Small Pulverized Coal Silo (SPCS) system between the direct-firing pulverizing system and the boiler, breaking the fuel supply bottleneck to provide flexible and rapid fuel feeding. A high-fidelity dynamic simulation model was developed, comprising a 350 MW boiler integrated with the SPCS system. The boiler subsystem within this coupled model was rigorously validated against actual plant data. The results demonstrate that the SPCS system significantly enhances the boiler load change rate, with the average ramp rate increasing from 1.26 %Pe/min (without SPCS) to 3.23 %Pe/min (with SPCS) when supplying pulverized coal at 7 kg/s within 2 minutes during the 50%-75% load range of boiler. Moreover, under an identical SPCS coal feeding strategy, the enhancement in load change rate was more pronounced in the lower load range (50%-75%) compared to the higher load range (75%-100%). Furthermore, to ensure the energy-mass balance during the rapid fuel feeding process enabled by the SPCS, a regulation strategy based on synchronized feedwater compensation is proposed. The modulating effect of the feedwater-to-fuel compensation ratio (WFRSPCS) on the boiler's dynamic characteristics was investigated. An optimal ratio of WFRSPCS = 5 was identified, which successfully maintains the main steam temperature stability while simultaneously yielding an additional main steam flow increment of approximately 25.4 kg/s. Consequently, this strategy achieves a coordinated enhancement in both the load response speed and the thermal stability of the boiler unit.

In-situ CO2 adsorption-enhanced H2 production technology for the WGS reaction holds promising application potential in the fields of low-carbon development and clean energy production. This study innovatively developed engineered nanoscale Cu-CeO2-MgO adsorptive-catalytic bifunctional systems by regulating the sequence of Cu impregnation and MgO gelation. Through multi-dimensional characterization and reactivity tests, the catalytic and adsorptive performance of the composite systems were systematically investigated. The results indicate that the introduction of Cu and Ce components modulates the surface electronic environment of MgO aerogels, inducing the reconstruction of surface basic sites and accelerating carbonation chemisorption. The binary and ternary metal-oxide/oxide-oxide interfaces (Cu-Ce-O-Mg) within the composites induce lattice distortion in CeO2 and MgO, while regulating the oxidation states, dispersion, and redox behavior of CuxO species. They also facilitate interfacial electron transfer among the multiple components, as evidenced by modulated distribution and coordination environment of Cu/Ce species and altered infrared/ultraviolet absorption features. Within the temperature range of 330–410 °C, the composites exhibit a remarkable enhancement in H2 production: the H2 yields of Cu-CeO2/MgO and Cu/CeO2-MgO surpass those of the physically mixed Cu-CeO2+MgO by 39.5% and 70.8%, respectively. The effective interfacial engineering of the composites simultaneously accelerates both CO conversion and CO2 capture, significantly enhancing the catalysis-adsorption synergy.

To address the issue of high‐temperature corrosion of coal‐fired boiler water‐cooled walls, an Al–Si–Cr coating with rare earth element is developed using heat‐curing ceramic coating technology in this study. The corrosion resistance of both Al–Si–Cr and Ni–Cr coatings is investigated under laboratory and actual boiler conditions using X‐ray diffraction, scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy. Results indicate significant coatings’ mass increase over time under laboratory conditions, with corrosion mass gain following a power function of time. The dense structure of the Al–Si–Cr coating and the rare earth elements effectively prevent the diffusion of corrosive gases, providing superior gaseous corrosion resistance. However, the dissolution of Al ₂ O ₃ in high‐temperature molten salt causes cracks, reducing its resistance in such environments. Ni–Cr coating oxides react with corrosive gases, diminishing its resistance to gaseous corrosion. Nevertheless, Cr inhibits the sulfidation of Ni in molten sulfate and stabilizes NiO, enhancing its corrosion resistance in molten salt. The Al–Si–Cr coating demonstrates outstanding anti‐coking and corrosion resistance in the boiler. This study provides a promising new solution for enhancing the corrosion protection of water‐cooled walls in coal‐fired boilers.