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Summary: Coal is the most abundant energy source, and around 40% of the world's electricity is produced by coal combustion. The emission generated through it put a constraint on power production by coal combustion. There is a need to reduce the emissions generated through it to utilize the enormous energy of coal for power production. Detailed understanding of various aspects of coal combustion is required to reduce the emissions from coal‐fired furnaces. The aim of present paper is to review various aspects of pulverized coal combustion such as oxy‐fuel combustion, co‐combustion of coal and biomass, emissions from pulverized coal furnaces, ash formation and deposition, and carbon capture and sequestration (CCS) technologies to outline the progress made in these aspects. Both experimental and numerical aspects are included in this review. This review also discusses the thermodynamic aspects of the combustion process. Furthermore, the effect of various submodels such as devolatilization models, char combustion models, radiation models, and turbulent models on the process of pulverized coal combustion has been investigated in this paper. [ABSTRACT FROM AUTHOR]

Detailed analyses based on mass and energy balances of lignite-fired air-blown gasification-based combined cycles with CO2 pre-combustion capture are presented and discussed in this work. The thermodynamic assessment is carried out with a proprietary code integrated with Aspen Plus® to carefully simulate the selective removal of both H2S and CO2 in the acid gas removal station. The work focuses on power plants with two combustion turbines, with lower and higher turbine inlet temperatures, respectively, as topping cycle. A high-moisture lignite, partially dried before feeding the air-blown gasification system, is used as fuel input. Because the raw lignite presents a very low amount of sulfur, a particular technique consisting of an acid gas recycle to the absorber, is adopted to fulfill the requirements related to the presence of H2S in the stream to the Claus plant and in the CO2-rich stream to storage. Despite the operation of the H2S removal section representing a significant issue, the impact on the performance of the power plant is limited. The calculations show that a significant lignite pre-drying is necessary to achieve higher efficiency in case of CO2 capture. In particular, considering a wide range (10-30 wt.%) of residual moisture in the dried lignite, higher heating value (HHV) efficiency presents a decreasing trend, with maximum values of 35.15% and 37.12% depending on the type of the combustion turbine, even though the higher the residual moisture in the dried coal, the lower the extraction of steam from the heat recovery steam cycle. On the other hand, introducing the specific primary energy consumption for CO2 avoided (SPECCA) as a measure of the energy cost related to CO2 capture, lower values were predicted when gasifying dried lignite with higher residual moisture content. In particular, a SPECCA value as low as 2.69 MJ/kgCO2 was calculated when gasifying lignite with the highest (30 wt.%) residual moisture content in a power plant with the advanced combustion turbine. Ultimately, focusing on the power plants with the advanced combustion turbine, air-blown gasification of lignite brings about a reduction in HHV efficiency equal to almost 1.5 to 2.8 percentage points, depending on the residual moisture in the dried lignite, if compared with similar cases where bituminous coal is used as fuel input. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]