The ever-increasing demand for steel and the subsequent depletion of high-grade ores requires the massive utilization of low-grade iron ores. In the present study, an iron ore slime sample containing 56.1% Fe was investigated using physical beneficiation, carbothermal reduction, and a microwave-assisted process; however, physical …
These wastes and by-products generally include weathered coal, mudstone, coal gangue and coal slime from coal mining and processing. Coal mining wastes mainly include weathered coal, which is produced from coal weathering in coal surface mining. Before mining, coal exists in a water-saturated, oxygen-free environment, any disturbance to …
Solid waste will be generated from the coal mining and washing process, namely coal slime (Hirschi, 2018, Wang et al., 2018). According to Statistical Review of World Energy, global coal output is still considerable. ... Except for pulverized coal boilers and down-fired boilers, the role of the air staging on the NO x emissions during CFB ...
Coal-based power plants with conventional stoke firing suffer from some shortcomings such as the inability to handle load fluctuations due to limited combustion capacity, difficulties in removing large quantities of ash, and interference of the formed ash in the combustion process. Pulverized coal combustion systems offer a viable solution to ...
ABSTRACT Coal slime, coal slime/CaO, and coal slime/CaO/pine sawdust were formed to make briquettes respectively. The effects of pine sawdust on the SO2 retention by CaO during coal slime briquette combustion were studied using a tube furnace. The obtained results demonstrated that porous structures were created in the …
The obtained products include clean coal, gangue, pulverized coal, and coal slime, respectively. The coal slime consists of primary coal slime and secondary coal slime produced in the separation process, with the yields of 0.56% and 5.08% respectively. In the fine coal system, the total yield of coal slime is 5.64%.
2.2 Coal combustion. Pulverized coal combustion (PCC) is the most widely used technology for coal power generation. In this process, coal is milled, pulverized, and injected in the boiler with air to allow combustion. Combustion takes place at temperatures from 1300 to 1700 °C, depending largely on coal rank [17].
Co-pyrolysis of the coal blend with lignocellulosic biomass has a significant influence on final product composition of co-gasification and co-combustion. Successful evaluation of …
In this paper, the combustion process of a 350 MW opposite pulverized coal combustion boiler is studied using a combined field test and numerical simulation. Considering the turbulence–radiation …
1. Introduction. Flame stability in pulverized coal combustion is becoming increasingly an area of concern due to the trends of extending the use of low-quality coal and coal blends in existing power industries [1].An unstable flame can cause many combustion problems, such as furnace vibration, low combustion efficiency, high NOx …
DOI: 10.1016/j.wasman.2021.10.035 Corpus ID: 243818166; Application of post-combustion ultra-low NOx emissions technology on coal slime solid waste circulating fluidized bed boilers.
Nitrogen oxides, being the second most toxic combustion product of pulverized coal fuel, turn to HNO 3 in the air and are the most common component of acid rains . ... (Kemerovo region, Russia) and coal slime was derived from the processing of coal of the same rank. Coal components were first ground in a rotor mill and riddled to …
Pulverized coal-fired units fire much or all of the lignite in suspension. Cyclone furnaces collect much of the ash as molten slag in the furnace itself. Stokers (other than spreader) retain a large fraction of the ash in the fuel bed and bottom ash. Spreader stokers fire about 15 percent of the coal in suspension and the remainder in a bed.
X-ray photoelectron spectroscopy (XPS, ESCALAB 250Xi, Thermo Fisher, Waltham, MA, USA) and X-ray diffraction (XRD, PANalytical Empyrean, PANalytical, …
This article describes an experimental study on NOx emissions in pulverized coal combustion after preheating and air staging. The process takes place in two stages: the pulverized coal is first preheated in a circulating fluidized bed, and then the resulting fuel gas and char particles are burned in a down-fired combustor under air …
Coal slime has low ash content, and adding coal slime during coal gangue combustion may have influence on combustion character; and at this process, NO will …
Coal has been important energy to support China's economy for a long time. However, the process of coal washing produces a massive of coal slime, with strong water holding capacity, high ash content, low calorific value, and strong adhesion [].According to official statistics, the production of coal slime has reached 195 million …
1. Introduction. The data of the 2021 Statistical Review of World Energy indicated that coal consumption accounts for about 27.2% of the world's total primary energy consumption and more than 40% of electricity is generated by coal [1].Coal slime as the by-product is produced during the coal washing process, which accounts for …
Characteristics of pulverized coals have significant influence on the spontaneous combustion and explosion processes. This paper presents an experimental and theoretical framework on physico-chemical characteristics of coal and their interrelations from spontaneous combustion and explosion perspectives. The chemical …
The paper provides an outlook on future directions of research and the possible applications for pulverized coal-fired boilers. One potential direction for future research is to focus on the ways to improve the efficiency of pulverized coal-fired boilers. This could involve developing new combustion technologies that are able to more …
In the process of raw coal washing, a large number of coal slime is generated. Coal slime is a very complex heterogeneous material composed of a large number of pulverized coal, colloid, organic debris, inorganic particles, bacteria, etc., with the characteristics of high moisture, high ash content, high viscosity and low calorific …
Coal slime is a common byproduct during coal processing, and the output of coal slime increased sharply with the increase in coal demand, the continuous improvement of coal mining mechanization ...
Since sewage sludge and coal slime are both inferior fuels with low calorific value, it is not suitable to use pulverized coal boiler for combustion, but it has a great potential to use the circulating fluidized bed boiler with wide fuel adaptability to realize the co-combustion treatment of sewage sludge and coal slime.
DOI: 10.1016/J.JECE.2021.106249 Corpus ID: 238664876; Investigation on combustion, gaseous pollutants emission and ash characteristics during co-combustion of semicoke and coal slime
Pulverized coal ignition becomes possible when methane concentration exceeds 1.25 vol% [48]. The ignition of a mixture of methane, air, and coal dust includes two stages: methane ignition and coal dust ignition. ... Coal slime, which is a typical coal processing waste, can be a good candidate, provided that its low calorific value is ...
Coal slime is a by-product of the process of coal preparation. Due to its special generation process, coal slime, whose particle sizes are less than 1 mm in general, is characterized by high water holding capacities, high ash and low heat values [7], [8]. Because of the above characteristics, coal slime is mostly abandoned directly or …
The coal components were coking bituminous coal from the Berezovskoe deposit (Kemerovo region, Russia) and coal slime was derived from the processing of coal of the same rank. Coal components were first ground in a rotor mill and riddled to obtain a fine powder with a particle size of no more than 100 m. This pulverized …
With the increasing amount of coal slime in the process of coal washing, it is of great significance to realize the clean utilization of coal slime for sustainability and environmental ... Characteristics of pulverized-coal combustion in the system of oxygen/recycled flue gas combustion. T. Kiga S. Takano +4 authors M. Kato. …
The effluent from this CFB flows to a pulverized coal combustor downstream for deep combustion. This technology has been recently commissioned in a 75 t/h CFB boiler. ... Despite the tremendous industrial success, the combustion of wet coal slime is a complex process and inevitably reduces the boiler's thermal efficiency [12], …
Research on the co-pyrolysis of coal slime and lignin based on the combination of TG-FTIR, artificial neural network, and principal component analysis. ... A modeling approach to co-firing biomass/coal blends in pulverized coal utility boilers: Synergistic effects and emissions profiles. Energy 2017, 120, ... Fuel Processing Technology 2016 ...
This study reports an experimental investigation on the nitrogen oxide (NOx) emissions in pulverized fuel (coal and char) combustion through preheating with a circulating fluidized bed. The high-temperature preheated fuel particles obtained from the circulating fluidized bed would be burned in the down-fired combustor. The focus of this …