Desulfurization wastewater is industrial wastewater with a high salt content, high metal ions, and high hardness produced by flue gas desulfurization of the limestone-gypsum method in coal-fired power plants. This paper summarizes the source of desulfurization wastewater, water quality characteristics, water quality impacts, and other factors, combined with the current status of research worldwide to introduce the advantages and shortcomings of the existing desulfurization wastewater treatment technology. In addition, zero liquid discharge technology as a novel method to treat desulfurization wastewater is also summarized. It mainly includes evaporation and crystallization, flue gas evaporation, membrane distillation removal, etc. Finally, this manuscript looks forward to the future development direction of desulfurization wastewater based on its existing technology and emission standards.

Regenerative combustion represents an efficient and energy-saving combustion technology that significantly enhances thermal efficiency, reduces energy consumption, and minimizes pollutant emissions by recovering and reusing heat energy. This technology has found extensive applications in traditional industries, such as chemical engineering, coating, and printing, as well as in contemporary fields, including food processing and pharmaceuticals. In recent years, advancements in the optimization of combustion devices and the development of efficient catalysts have successfully reduced the combustion temperature for treating organic waste gases while simultaneously improving pollutant removal efficiency. This paper reviews the current status of regenerative combustion technology, summarizes key achievements, analyzes the challenges faced in industrial applications, and anticipates future research directions.

Hydrogen (H₂) is considered one of the main pillars for transforming the conventional “dark” energy system to a net-zero carbon or “green” energy system. This work reviewed the potential resources for producing low-carbon hydrogen in China, as well as the possible hydrogen production methods based on the available resources. The analysis and comparison of the levelized cost of hydrogen (LCOH) for different hydrogen production pathways, and the optimal technology mixes to produce H₂ in China from 2020 to 2050 were obtained using the mixed-integer linear programming (MILP) optimization model. The results were concluded as three major ones: (a) By 2050, the LCOH of solar- and onshore-wind-powered hydrogen will reach around 70–80 $/MWh, which is lower than the current H2 price and the future low-carbon H₂ price. (b) Fuel costs (>40%) and capital investments (~20%) of different hydrogen technologies are the major cost components, and also are the major direction to further reduce the hydrogen price. (c) For the optimal hydrogen technology mix under the higher renewable ratio (70%) in 2050, the installed capacities of the renewable-powered electrolysers are all more than 200 GW, and the overall LCOH is 68.46 $/MWh. This value is higher than the LCOH (62.95 $/MWh) of the scenario with higher coal gasification with carbon capture and the storage (CG-CCS) ratio (>50%). Overall, this work is the first time that hydrogen production methods in China has been discussed comprehensively, as well as the acquisition of the optimal H2 production technology mix by the MILP optimization model, which can provide guidance on future hydrogen development pathways and technology development potential in China.

The advancement of biomass-circulating fluidized bed (CFB) gasification technology in China for commercialization and industrial application is still in its initial stages, characterized by extensive theoretical studies; however, there is limited documentation of its actual industrial operational characteristics. This study analyzes the operational challenges encountered in a 5 t/h biomass CFB gasifier at a rice factory in Jiangsu Province, China. It examines critical issues emerging during the gasifier system’s actual operational process, including the obstruction of the feeding system, the measurement of pressure at point blockages in the dense phase zone, loop seal blockages, bed inventory leakage of the blast cap on the air distribution plate, and gasification parameter fluctuations. Practical improvement strategies and implementation plans are proposed to address these operational concerns. The outcomes of this analysis serve as a reference for the design and operation of biomass CFB gasifiers. Furthermore, they provide crucial guidance for more extensive large-scale implementation of biomass CFB gasifiers.

Denitrification technology in thermal power plants plays a critical role in reducing nitrogen oxide (NOx) emissions, thereby improving air quality and mitigating climate change. This study conducts a numerical simulation of the SCR (Selective Catalytic Reduction) system at the Chizhou Power Plant to optimize its flow field configuration. The original system exhibited severe flow non-uniformity, with local maximum velocities reaching 40 m/s and a velocity deviation coefficient of 28% at the inlet of the first catalyst layer. After optimizing the deflector design, the maximum local velocity was reduced to 21 m/s, and the velocity deviation coefficient decreased to 14.1%. These improvements significantly enhanced flow uniformity, improved catalyst efficiency, and are expected to extend equipment service life. The findings provide a practical reference for the retrofit and performance enhancement of SCR systems in similar coal-fired power plants.