Combustion Of Coal Gangue Research Articles

Three-dimensional distribution and oxidation degree analysis of coal gangue dump fire area: A case study

Spontaneous combustion of coal gangue dumps poses a significant threat to the health and safety of nearby residents and has adverse effects on the environment. The establishment of measures to extinguish these fires requires information on the three-dimensional characteristics and oxidation degree of the dumps. An acquisition method for the index data was proposed. The temperature and the radon concentration were used as the principal indicators, and the gas concentration was a secondary index for verifying the results. Kriging interpolation was applied to predict the value of the unsampled points. Additionally, the three-dimensional characteristics of the temperature and radon anomalies were determined, thresholds were set, and the changes in the temperature and radon migration were considered to estimate the extent and depth of the fire in the coal gangue dumps. The oxidation degree of the anomalous area was identified according to the critical value of the temperature and radon anomalies. The application of this method in the gangue dump of the Tashan coal mine showed the existence of 17 oxidation areas, covering an area of 31,433 m2, including 4 shallow oxidation areas, 4 deep oxidation areas in coal waste dumps, and 9 medium-deep oxidation areas. According to the decision criterion, 4 areas with relatively high oxidation degree were identified, whereas the remaining sites were low-oxidation areas. Additionally, surface fires and internal fires can be transformed into each other, posing a significant threat. The results obtained from the various data sources were consistent and in agreement with the ground survey results, indicating that the proposed method is effective for the detection of fires in coal gangue dumps.

A Simplified Model for SO2 Generation during Spontaneous Combustion of Coal Gangue

A simplified model for SO2 generation during spontaneous combustion of coal gangue was put forward and validated using the measured data. Using the proposed model, the effects of initial temperature inside the gangue and fresh air supply on SO2 generation were discussed. The results showed that, higher initial temperature inside the gangue could accelerate the oxidation rate of FeS2 and increase the maximum concentration of SO2. If initial temperature inside the gangue increased by about 37%, the total SO2 generation increased by 166%. Fresh air supply had less significant effect on the oxidation rate of FeS2. However, the higher the fresh air supply was, the more FeS2 could be oxidized, which ultimately produced more SO2. Although the computed results and the measured data concerning the inner locations inside the gangue had a certain degree of error, the proposed model can provide a relatively precise total release of SO2 within acceptable accuracy. Besides, this method provides a useful prototype to predict the generation of hazardous materials, such as CO, NOx, and chlorine during the spontaneous combustion of coal gangue.

What are the environmental advantages of circulating fluidized bed technology? ——A case study in China

In this paper, the environmental cost and environmental benefit evaluation system of circulating fluidized bed (CFB) technology is established by analyzing the environmental damage caused by coal-fired power generation and comparing circulating fluidized bed boilers with ordinary coal-fired boilers. Among them, the environmental cost is mainly the cost of desulfurization equipment and sellout equipment. Environmental benefits include internal environmental benefits and external environmental benefits. The internal environmental benefits mainly include the cost savings from desulfurization and denitrification to reduce the emission of polluting gases and the benefits from the comprehensive utilization of the ash from the circulating fluidized bed boiler. The external environmental benefits mainly include the reduction of occupied farmland, the emission of waste gas caused by spontaneous combustion of coal gangue and the pollution of water resources. After measuring the environmental costs and benefits of CFB technology, this paper further estimated its value. On this basis, particle swarm optimization (PSO) with extreme learning machine (ELM) intelligent algorithm was used to predict the scenario of thermal power generation and evaluate the environmental benefits of CFB units in the future through further calculation.

Study on the environmental effects of heavy metals in coal gangue and coal combustion by ReCiPe2016 for life cycle impact assessment

During coal and coal gangue combustion, many heavy metal pollutants are emitted and cause serious environmental problems. In this paper, the environmental effect values of As and Pb emission during coal gangue and coal combustion in the 330 MW pulverized coal boiler, 50 kW circulated fluidized bed boiler and laboratory were calculated by ReCiPe2016. The results show that when coal combustion in 330 MW pulverized coal boiler, the environment effect values of as for bottom slag, fly ash and flue gas are 3.28×10−6, 2.68×10−5 and 3.89×10−3 respectively; while the environment effect value of Pb for bottom slag, fly ash and flue gas are 8.57×10−6, 6.00×10−5 and 4.83×10−2, respectively. The environmental effects of As and Pb in bottom slag are lower than those in the fly ash; and the environmental effects of As and Pb on air are higher than those on soil. Moreover, when coal combustion in the 50 kW circulated fluidized boiler, the effect values of As and Pb in fly ash on environment are 3.26×10−5 and 1.28×10−4; and the effect values of As and Pb in bottom slag are 1.16×10−6 and 1.43×10−5 respectively. The results also show that when coal gangue combustion in the laboratory, the effect values of As and Pb emission increase with increasing of the temperature; and the proportions of total environmental effects of As and Pb on air are higher than those on soil. Besides that, this study also indicates that the effect of Pb emitted into environment is higher than that of As at the same conditions during coal combustion both in circulated fluidized boiler and pulverized coal boiler. The results may provide basic data for predicting the environmental effects of As and Pb during coal gangue combustion in circulating fluidized bed for life cycle impact assessment.

The hydration properties of blended cement containing ultrafine fly ash with particle size less than 17 μm from the circulating fluidized bed combustion of coal gangue

This paper presents the proposal of the particle size range of circulating fluidized bed fly ash (CFA) that was positively associated with properties of blended cement by gray correlation analysis. Then, the hydration characteristics of blended cement containing ultrafine CFA (UCFA) with the above-suggested particle size distribution are studied from the physical and mechanical properties, hydration heat, non-evaporable water content, morphologies and pore structure. The results show that there is a positive association between CFA particles of less than 17 μm (especially 3–8 μm) and property of blended cement, while there is a negative association for particles of more than 17 μm, so the particles content of less than 17 μm should be improved in CFA as much as possible. The industrial UCFA, whose particle content of less than 17 μm reaches 98.18%, is prepared. The blended cement containing 10% UCFA possesses excellent properties, which ever surpasses pure portland cement. Furthermore, the physical and mechanical properties of blended cement containing no more than 30% UCFA meets the Chinese cement standard of 42.5 grade. With increase in the addition amount of UCFA, the hydration rate and degree of blended cement are gradually decreased and the influence is small at the addition amount of no more than 30%. The addition of 10% UCFA can optimize the pore structure of cement system, and the effect of 30% UCFA on the microstructure of cement gradually decreases with ages.

Effect of oxygen concentration on oxy-fuel combustion characteristic and interactions of coal gangue and pine sawdust

Coal gangue is an inevitable coal waste from coal mine, which results in serious environmental problems. Oxy-fuel firing of coal waste and biomass waste is an alternative technology for efficient and clean utilization and CO2 reduction of coal waste. In this study, the oxy-fuel combustion characteristics and interactions of coal gangue and pine sawdust were investigated using thermogravimetric analysis, with a focus on the effect of oxygen concentration on interactions between coal gangue and pine sawdust during oxy-fuel combustion. The oxy-fuel combustion of pine sawdust had two obvious stages, including the release of volatile matter and the combustion of the remaining char, which differed from oxy-fuel combustion of coal gangue with one overlapped stage of devolatilization and char oxidation. Moreover, the addition of pine sawdust could improve the oxy-fuel combustion reactivity of coal gangue. The significant deviations between the experimental derivative thermogravimetric curves and theoretical derivative thermogravimetric curves for the blends indicated that interactions between coal gangue and pine sawdust had occurred in the temperature range of 400–600 °C. The interaction mechanism was primarily thermal effect between coal gangue and pine sawdust during oxy-fuel combustion. The oxygen concentration had a significant effect on the interactions between coal gangue and pine sawdust. The increase of oxygen concentration from 20% to 40% could improve interactions between coal gangue and pine sawdust obviously. However, relative small improvement of interactions was detected between coal gangue and pine sawdust when oxygen concentration was further increased from 60% to 80%. This was related to the difference of rate controlling factor for oxy-fuel combustion reaction under various oxygen concentrations.

Laboratorial Investigation and Simulation Test for Spontaneous Combustion Characteristics of the Coal Waste under Lean-Oxygen Atmosphere

ABSTRACTAs a typical solid waste, coal gangue is highly susceptible to spontaneous combustion. Conventionally, method for controlling spontaneous combustion of coal gangue is to inhibit the oxidation and self-heating of gangue by utilizing soil covering to isolate the gangue from oxygen. Using various methods, such as FTIR, TG/DSC, program heating and physical simulation, the change of spontaneous combustion characteristics (SCCs) of coal gangue under 3–21.0% O2 was explored. Results show that lean-oxygen significantly decrease the heat release from coal gangue during low-temperature oxidation, inhibit the generation of O-containing functional groups, and postpone the appearance of characteristic temperature points on the thermogravimetry (TG) curve. Between 30 and 140°C, the activation energy during oxidation of coal gangue ranges 29.85–47.72 KJ/mol. The oxygen consumption rate (OCR) of coal gangue showed a nonlinear positive correlation with O2 concentration. Field simulation test showed that after coal gangue was stacked for 60 d, the gangue temperature rose to 39.6°C. After covering the soil, the temperature data increased slowly. However, oxidation of coal gangue was not completely inhibited even the lowest O2 concentration reduced to 18.35%. In conclusion, investigation in the paper provides further guidance for reducing risk of gangue self-ignition.

Experimental study of the effects of stacking modes on the spontaneous combustion of coal gangue

Coal gangue is a solid waste material which is generated during coal mining processes. Due to its low utilization value, it is normally discarded on gangue fields where it is stacked into very large hill formations. Spontaneous combustion is one of the major hazards which frequently occur during the long-term stacking of coal gangue. This study targeted the coal gangue stacks of the Chengzhuang Coal Mine, located in China’s Shanxi Province. The results of programmed heating tests helped determine that CO and C2H4 could be used as the index gases in the predictions of the self-heating degrees of coal gangue. Four of the typical coal gangue stacking modes which were often adopted by the Chengzhuang Mine were selected as the experimental objects of this study. The corresponding coal gangue models were piled in a field, and the self-heating degrees were measured with the passage of time. The entire experiment lasted for 60 days. The results showed that the loess isolation and loess stratified stacking methods could effectively suppress the self-heating processes. Also, the CO production and O2 consumption of the coal gangue were consequently reduced. The study also indicated that in the loess stratified stacking, the inhibitory effects on the spontaneous combustion of the coal gangue had increased with the increased thicknesses of the loess layers.

Decomposition of key minerals in coal gangues during combustion in O2/N2 and O2/CO2 atmospheres

Thermal decomposition characteristics of kaolinite and dolomite during combustion of coal gangues in different O2/N2 and O2/CO2 mixtures, simulating normal air and oxy-fuel combustion atmospheres, were examined using thermogravimetric analysis (TGA), with a focus on the effect of O2 and CO2 concentrations. A kaolinite-rich coal gangue and a dolomite-rich coal gangue were studied along with their low-temperature ashes prepared by oxidising the organic matter in an oxygen plasma asher thus leaving the minerals in their original form. The TGA experiments were carried out in O2/N2 and O2/CO2 atmospheres with varying O2 concentration and from room temperature to 950 °C at a heating rate of 10 °C min−1. The thermogravimetric (TG) and differential thermogravimetric (DTG) curves of these samples were examined and compared so as to reveal key thermal events and the on-set temperatures of their occurrence. The results showed that in both pyrolysis and O2/N2 atmospheres, the mass loss of the kaolinite-rich coal gangue occurred in the temperature range of 300–600 °C in one single stage, but the mass loss of the dolomite-rich coal gangue occurred at 300–730 °C in two distinct stages. In the O2/CO2 atmospheres, the mass loss of the kaolinite-rich coal gangue retained the one stage behaviour, however, the dolomite-rich coal gangue featured a three-stage mass loss event. Compared to their low-temperature ashes, the temperature range of mass loss of the kaolinite-rich coal gangue was consistent with that of its low-temperature ash in N2, O2/N2 and O2/CO2 atmospheres. The temperature range of mass loss of the dolomite-rich coal gangue in the second stage corresponded to that of the low-temperature ash in N2 and O2/N2 atmospheres and the temperature range of mass losses in the second and third stages corresponded to that of the low-temperature ash in O2/CO2 atmospheres. These observations indicate that kaolinite decomposed concurrently with the host coal gangue combustion while dolomite decomposed after the combustion. In addition, the decomposition of dolomite changed from a one-step reaction to a two-step reaction while kaolinite decomposition remained unchanged as the gas environment was changed from O2/N2 atmospheres to O2/CO2 atmospheres. When oxygen concentration increased from 2% to 21% in the O2/N2 atmosphere and 20% to 80% in the O2/CO2 atmosphere, the mass loss curves of the two coal gangues moved towards lower temperatures and the ignition temperature decreased. However, the mass loss of the kaolinite-rich coal gangue always showed a single peak characteristic regardless of the oxygen concentration while the mass loss of the dolomite-rich coal gangue was affected significantly by decreasing the O2 concentration in O2/N2 atmospheres and increasing the CO2 concentration in O2/CO2 atmospheres. This was attributed to the partial overlap of carbon combustion and dolomite decomposition in the O2/N2 atmosphere with low O2 concentrations and the suppression of dolomite decomposition in the O2/CO2 atmosphere.

Atmospheric emission of mercury due to combustion of steam coal and domestic coal in China

To study the mercury emission due to the combustion of steam coal and domestic coal in China, we analyzed the mercury contents of coal, fly ash, bottom ash and sluicing water in thermal power plants, steam boilers as well as domestic coal-stoves, in Shaanxi, Shanxi, Shandong and Yunnan Provinces. This study conduct an estimate of the Hg emission rates from steam coal and domestic coal combustion based on the method of mass distribution ratio of fly ash and bottom ash. The results show that the Hg emission rate of coal combustion in thermal power plants is about 50.21% (electrostatic precipitators + wet flue gas desulfurization), and that in heating boilers is about 67.23%, and 92.28% in industrial boilers without flue gas desulphurisation equipment. Furthermore, Hg emission rate is 83.61% due to domestic coal combustion in coal-stoves. The Hg emission amount into the atmosphere from power and heat generation, industrial boilers, domestic coal-stoves and spontaneous combustion of coal gangue is roughly estimated to be 133 ± 4, 100 ± 17, 11 ± 0.1 and 47 ± 26 tons in China in 2014, respectively, and the total Hg emission amount from this paper is estimated at 292 tons. The trends of Hg emission in China from 1991 to 2014 show an accelerating growth after 2002. The proportion of mercury emission due to thermal power, heating generation and industrial energy utilization continuously increased. The atmospheric emission of mercury due to combustion of steam coal, domestic coal and coal gangue accounts nearly 50% in total anthropogenic Hg emissions in China, indicating one of the largest sources of Hg emission in China which should draw more public and scientific attention in the future.

Influence of temperature and airflow on polycyclic aromatic hydrocarbons (PAHs) by simulated self-combustion of coal partings

Simulation of spontaneous combustion of partings in intermediate rank coal, aiming to study the influence of temperature and airflow on the formation and emission of 16 PAHs (Polycyclic Aromatic Hydrocarbons) specified by US Environmental Protection Agency as priority pollutants, and investigate the origin of PAHs. The experiments were performed from 50°C to 950°C, varying the airflow rates from 300mlmin∧1 to 1200mlmin∧1, with a constant interval time of50min. PAHs released from spontaneous combustion were collected by XAD-2 resin and dichloromethane solvent, then extracted with Soxhlet extraction method. High performance liquid chromatography (HPLC) was used to analyze the amount and composition of PAHs. The result indicates that the amount and toxicity of PAHs are much higher after self-combustion of coal wastes. Furthermore, oxidization of coal gangue at lower temperature stage (50°C•450°C) released much more PAHs and toxicity than that of combustion of coal gangue at higher temperature stage (550°C•950°C) basically. LPAHs (Low molecular weight PAHs)with two- and three-ring dominate the total PAHs yields, and the HPAHs (High molecular weight PAHs) ratios at high temperatures are relatively higher than that at low temperatures. The distribution of PAHs from coal wastes self-combustion indicates that the PAHs emitted are most undecomposed PAHs from petrogenic source, but with temperature increasing, the intensity of oxidation and pyrolyzation cause the total amount of PAHs decreased and HPAHs ratio increased.

Interactions of coal gangue and pine sawdust during combustion of their blends studied using differential thermogravimetric analysis

The interactions between coal gangue and pine sawdust during the combustion process were studied using thermogravimetric analysis. The effect of the blending ratio, oxygen concentration and heating rate on the weight loss (TG) and differential thermogravimetric (TGA) profiles was examined. The TG and DTG curves of the blends were not additives of those of the individual materials, suggesting that interactions between coal gangue and pine sawdust had occurred during the combustion, especially in the temperature range of 400–600°C. Kinetic analysis confirmed that the combustion of coal gangue, pine sawdust and their blends was chemical reaction controlled. Further analysis revealed that the interactions between coal gangue and pine sawdust were primarily due to thermal effects rather than structural changes, with the thermal inertia of coal gangue dominating over the behaviour of the blends. The interactions decreased with decreasing the coal gangue ratio in the blend, oxygen concentration and heating rate.

Estimate of sulfur, arsenic, mercury, fluorine emissions due to spontaneous combustion of coal gangue: An important part of Chinese emission inventories

A rough estimate of the annual amount of sulfur, arsenic, mercury and fluoride emission from spontaneous combustion of coal gangue in China was determined. The weighted mean concentrations of S, As, Hg, and F in coal gangue are 1.01%, 7.98, 0.18, and 365.54 mg/kg, respectively. Amounts of S, As, Hg, and F emissions from coal gangue spontaneous combustion show approximately 1.13 Mt, and 246, 45, and 63,298 tons in 2013, respectively. The atmospheric release amount of sulfur from coal gangue is more than one tenth of this from coal combustion, and the amounts of As, Hg, and F are close to or even exceed those from coal combustion. China's coal gangue production growth from 1992 to 2013 show an obvious growth since 2002. It may indicate that Chinese coal gangue has become a potential source of air pollution, which should be included in emission inventories.

Characterization of the Modes of Occurrence of Mercury and Their Thermal Stability in Coal Gangues

The utilization of coal gangue in a power plant has attracted wide interest in China; however, coal gangue represents a new anthropogenic source of mercury pollution due to its high mercury content. Understanding the modes of occurrence of mercury in coal gangue is crucial for developing the mercury control technology used during coal gangue combustion. In this study, the mercury in four typical coal gangues in China was characterized by a sequential extraction procedure (SEP) coupled with a temperature-programmed decomposition (TPD) method. The method is proved to be an effective approach in studying the modes of occurrence of mercury as well as the thermal stability of coal gangues by distinguishing the characteristic release temperature during the thermal decomposition process. The iron–manganese oxide-bound Hg releases at a temperature range of 200–600 °C, while the carbonate-bound Hg releases at a temperature range of 250–300 °C. The organic-bound Hg, sulfide-bound Hg, and silicate-bound Hg release a...

Investigation of combustion characteristics and kinetics of coal gangue with different feedstock properties by thermogravimetric analysis

The combustion behavior of eleven coal gangue was investigated by thermogravimetric analysis (TGA). The effects of feedstock properties (combustible matter and mineral matter) on combustion characteristics of coal gangue were analyzed. The kinetic parameters were obtained based on experimental results by distributed activation energy model (DAEM). The results show that the ignition temperature of coal gangue is affected by volatile content and oxygen adsorption behavior jointly. In the main weight loss stage, combustion reaction of combustible matter and dehydroxylation reaction of mineral matter proceeded simultaneously. Combustion conditions of volatile matter and fixed carbon, as well as, decomposition of kaolinite, illite and calcite exhibited different characteristic DTG curves. The activation energy for the combustion of coal gangue was in the range of 117–300kJ/mol. Feedstock properties affected the change of activation energy with conversion values. The maximum relative errors between calculated and experimental results by DAEM model were 0.2–0.5%.

Trace element partitioning behavior of coal gangue-fired CFB plant: experimental and equilibrium calculation

Energy recovery is a promising method for coal gangue utilization, during which the prevention of secondary pollution, especially toxic metal emission, is a significant issue in the development of coal gangue utilization. In the present study, investigation into trace element partitioning behavior from a coal gangue-fired power plant in Shanxi province, China, has been conducted. Besides the experimental analysis, thermodynamic equilibrium calculation was also conducted to help the further understanding on the effect of different parameters. Results showed that Hg, As, Be, and Cd were highly volatile elements in the combustion of coal gangue, which were notably enriched in fly ash and may be emitted into the environment via the gas phase. Cr and Mn were mostly non-volatile and were enriched in the bottom ash. Pb, Co, Zn, Cu, and Ni were semi-volatile elements and were enriched in the fly ash to varying degrees. Equilibrium calculations show that the air/fuel ratio and the presence of Cl highly affect the element volatility. The presence of mineral phases, such as aluminosilicates, depresses the volatility of elements by chemical immobilization and competition in Cl. The coal gangue, fly ash, and bottom ash all passed the toxicity characteristic leaching procedure (TCLP), and their alkalinity buffers the acidity of the solution and contributes to the low solubility of the trace elements.

Partitioning and transformation behavior of toxic elements during circulated fluidized bed combustion of coal gangue

A study on toxic elements behaviors from a 330MW coal gangue circulated fluidized bed co-combustion power plant equipped with electrostatic precipitators (ESPs) was performed. Simultaneous sampling of feed coal, bottom ash, fly ash and flue gas were implemented. Sequential chemical extraction was taken to investigate the transformation behaviors of toxic elements. The relative distribution and partitioning behavior of toxic elements in the power plants were analyzed systemically. The toxic elements can be divided into two groups, Cluster one, whereby high volatile tendencies are represented by As, Cd, Cu, Pb, Se and Sn which have a volatilization ratio more than 20% and are mainly enriched in fly ash. These elements are primarily associated with sulfide minerals. Cluster two, represented by Co, Cr, Mn and V, have low volatilization rate (⩽5%) and are equally distributed between bottom ash and fly ash. In addition, Bi, Ni and Zn may be located between Cluster one and Cluster two. The variation of modes of occurrence of toxic elements could lead to the difference of transformation behaviors during the combustion of feed coal. Most toxic elements transformed and partitioned into other fractions from Fe–Mn oxides during combustion.

Combustion Characteristics of Coal Gangue under an Atmosphere of Coal Mine Methane

Combustion characteristics of coal gangue under O2/N2 mixtures with different O2 concentrations and coal mine methane (CMM) conditions were investigated by using thermogravimetric analysis (TGA) and tube reactor tests. Calculation results for the combustion characteristic parameters show that ignition temperature, burnout temperature, and peak temperature increase, while the maximum and average combustion rates decrease with decreasing O2 concentrations. The mass loss decreases and comprehensive combustion characteristic index increases slightly when CH4 is present in the combustion atmosphere with equivalent O2 concentration. TGA and tube reactor tests indicate that the mass loss of coal gangue is mainly attributed to the combustion of volatile matter and of fixed carbon. A temperature rise to ∼650 °C markedly inhibits carbon combustion because of O2 consumption caused by combustion of CH4 and H2 produced from CH4 cracking. Kinetic parameters (apparent activation energy (E), reaction order, and frequency factor) were calculated for various atmospheres by direct linear regression of the kinetic equation from a single TGA curve. The E value of coal gangue combustion varies from 117.6 to 137.4 kJ/mol under different atmospheres, and is slightly higher in CMM than in the O2/N2 mixture with equivalent O2 concentration.

Pyrolysis and Combustion Behavior of Coal Gangue in O2/CO2 and O2/N2 Mixtures Using Thermogravimetric Analysis and a Drop Tube Furnace

Combustion of coal gangue is extensively used for power generation in China. In this paper, pyrolysis and combustion characteristics of a low-rank coal gangue have been investigated under oxy-fuel (O2/CO2) and air (N2/O2) conditions using a drop tube furnace and thermogravimetric analysis. Pyrolysis experiments were carried out in N2 and CO2 environments, which are the main diluting gases of air and oxy-fuel environments, respectively. The burnout and yields of volatile matter were analyzed during DTF experiments. At lower temperatures, the weight loss rate of coal gangue during pyrolysis in N2 was higher than that in CO2. However, further weight loss took place in CO2 atmosphere at temperatures above 800 °C due to CO2 gasification of chars. The thermogravimetric analysis (TGA) results confirmed that the pyrolysis in CO2 environment can be divided into three stages: moisture release, devolatilization, and char gasification by CO2 in a higher temperature zone. Combustion experiments were carried out in fou...

Transformation behavior of mineral composition and trace elements during coal gangue combustion

The transformation behavior of mineral and trace elements during combustion of Chinese coal gangue at varies temperatures were studied. The coal gangue sample was placed at muffle roaster and heated up to 8-desired temperature points, from 500°C to 1200°C with 100°C for each interval. The mineral compositions of coal gangue and its combustion ash were determined by X-ray powder diffraction techniques (XRD). FTIR spectroscopy analysis was taken to determine coal gangue and combustion ash functional group, phase transition characteristics and the variation in combustion. The concentration of trace element in coal gangue and combustion ash was analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Results show that the transformation behavior of mineral phase of coal gangue mainly relies on the combustion temperature. The volatilize ratios of selected trace elements increase with increasing combustion temperature. Besides, 10 trace elements studied in the current study can be classified into two categories according to their volatilize tendencies: (a) Ni, Cu, Zn, Cd, Sn, Pb and As were vaporized at intermediate temperature and have high volatilize ratio; (b) V, Cr, and Co were relative non-volatile.