Coal combustion is the primary anthropogenic source of atmospheric iodine, which has important environmental and health effects. The iodine distribution in Chinese coals and the atmospheric iodine emission factors of coal-fired boilers are studied to estimate the iodine atmospheric flux from coal combustion in China from 1995 to 2009. The national average iodine content weighted by coal yield f...

The beneficiation of coal through gravity separation plays a key role in industry, allowing for particle size distribution determination and separation of coal in to various sizes for future combustion in boilers, and separation of impurities. For a complete combustion an industrial suspension boiler using bituminous coal requires an average particle size of 45μm and 80 to 85% of particles to b...

Combustion profiles determined by TGA and experiments in a laminar entrained flow reactor (EFR) were used in this work to assess the relative combustion reactivities of different rank coals and their binary coal blends. The combustion behaviour of coal blends in TGA was greatly influenced by coal rank and the proportion of each component in the blend. Higher volatile coals exerted more influenc...

According to statistics, the coal spontaneous combustion fire accounted for more than 94% of the total number of coal mine fire, of which 60% occur in gob [1]. With the mining depth increasing, coal pillar become so easy to be crushed that coal spontaneous combustion is easier to occur. The fire’s occurrence and development not only affect the safety in production and the surrounding environmen...

Combustion and Gasification are commercial processes of coal utilization, and therefore continuous improvement is needed for these applications. The difference between these processes is the reaction mechanism, in the case of combustion the reaction products are CO2 and H2O, whereas in the case of gasification the products are CO, H2 and CH4. In order to investigate these processes further, a s...

Oxygen-enhanced and oxygen-fired pulverized coal combustion is actively being investigated to achieve emission reductions and reductions in flue gas cleanup costs, as well as for coal-bed methane and enhanced oil recovery applications. To fully understand the results of pilot scale tests and to accurately predict scale-up performance through CFD modeling, accurate rate expressions are needed to...

Future use of coal for power generation in the US depends on technologies being made available to capture and store CO2 emissions from power plants. A key candidate CO2 capture technology is oxy-firing of coal. Application of oxy-firing to existing power plants presents unquantified challenges as the characteristics of oxy-firing compared to airfiring have not been fully determined. This presen...

Combustion mechanism of a 300 MW pulverized coal boiler is analyzed and the optimization of the performance of the boiler is carried out. The flow field, temperature field, devolatilization, char combustion and CO generation in the boiler furnace under actual condition is obtained by using Fluent. Three methods to improve the efficiency of boiler combustion are proposed based on the pulverized ...

The increasing environmental concern caused by the use of fossil fuels and the concomitant need for improved combustion efficiency is leading to the development of new coal cleaning and utilisation processes. However, the benefits achieved by the removal of most mineral matter from coal either by physical or chemical methods can be annulled if poor coal combustibility characteristics are attain...